Electronic Brachytherapy for Nonmelanoma Skin Cancer - CAM 80162

Description:
Electronic brachytherapy is a form of radiotherapy designed to deliver high-dose rate radiation to treat nonmelanoma skin cancer. This technique focuses a uniform dose of X-ray source radiation to the lesion with the aid of a shielded surface application.

For individuals who have nonmelanoma skin cancer who receive electronic brachytherapy, the evidence includes case series. Relevant outcomes are overall survival, disease-specific survival, change in disease status, and treatment-related morbidity. No controlled trials were identified that compared electronic brachytherapy with alternative treatment options. The cases series, which usually contained mixed patient populations of basal and squamous cell carcinomas, reported low rates of recurrence, ranging from 0% to 3%, at follow-up periods ranging from 10 to 66 months. Skin toxicity is relatively common, but usually mild. Controlled trials are needed in defined populations that compare electronic brachytherapy with alternatives, either other forms of radiotherapy or surgical approaches. The evidence is insufficient to determine the effects of the technology on health outcomes.

Background:
Nonmelanoma Skin Cancer
Squamous cell carcinoma and basal cell carcinoma are the most common types of nonmelanoma skin cancer in the United States, affecting between 1 million and 3 million people per year1,2 and increasing at a rate of 3% to 8% per year.2 Other types (e.g., T-cell lymphoma, Merkel cell tumor, basosquamous carcinoma, Kaposi sarcoma) are much less common. The primary risk factor for nonmelanoma skin cancer is sun exposure, with additional risk factors such as toxic exposures, other ionizing radiation exposure, and immunosuppression playing smaller roles.2 Although these cancers are rarely fatal, they can impact the quality of life, functional status, and physical appearance.

Treatment
In general, the most effective treatment for nonmelanoma skin cancer is surgical. If surgery is not feasible or preferred, cryosurgery, topical therapy, or radiotherapy can be considered, though the cure rate may be lower.3 When considering the most appropriate treatment strategy, recurrence rate, preservation of function, patient expectations, and potential adverse events should be considered.

Surgical
The choice of surgical procedure depends on the histologic type, size, and location of the lesion. Patient preferences can also play a factor in surgical decisions due to cosmetic reasons-as well as the consideration of comorbidities and patient risk factors, such as anticoagulation. Local excisional procedures, such as electrodesiccation and curettage or cryotherapy, can be used for low-risk lesions, while surgical excision is indicated for lesions that are not low risk. Mohs surgery is an excisional procedure that uses microscopic guidance to achieve greater precision and sparing of normal tissue. In patients who meet criteria for Mohs surgery, 5-year cure rates for basal cell cancer range from 98% to 99%,4 making Mohs surgery the preferred procedure for those who qualify.

Radiotherapy
Radiotherapy is indicated for certain nonmelanoma skin cancers not amenable to surgery. In some cases, this is due to the location of the lesion on the eyelid, nose, or other structures that make surgery more difficult and which may be expected to have a less desirable cosmetic outcome. In other cases, surgery may be relatively contraindicated due to clinical factors, such as bleeding risk or advanced age. In elderly patients with a relatively large tumor that would require extensive excision, the benefit/risk ratio for radiotherapy may be considered favorable. The 5-year control rates for radiotherapy range from 80% to 92%, which is lower than that of surgical excision.4 A randomized controlled trial by Avril et al. (1997) reported that radiotherapy for basal cell carcinoma resulted in greater numbers of persistent and recurrent lesions compared with surgical excision.5

When radiotherapy is used for nonmelanoma skin cancer, the primary modality is external-beam radiotherapy. A number of different brachytherapy techniques have also been developed, including low-dose rate systems, iridium-based systems, and high-dose ratesystems.4

Electronic Brachytherapy
Electronic brachytherapy is a form of radiotherapy delivered locally, using a miniaturized electronic X-ray source rather than a radionuclide-based source. A pliable mold, constructed of silicone or polymethyl-methacrylate, is fitted to the tumor surface. This mold allows treatment to be delivered to nonflat surfaces such as the nose or ear. A radioactive source is then inserted into the mold to deliver a uniform radiation dosage directly to the lesion.4 Multiple treatment sessions within a short time period (typically within a month) are required.

This technique is feasible for well-circumscribed, superficial tumors because it focuses a uniform dose of X-ray source radiation on the lesion with the aid of a shielded surface application. Advantages of this treatment modality compared with standard radiotherapy include a shorter treatment schedule, avoidance of a surgical procedure and hospital stay, less severe side effects because the focused radiation spares healthy tissue and organs, and the avoidance of radioisotopes. 

Regulatory Status: 
Electronic brachytherapy systems for the treatment of nonmelanoma skin cancers are designed to deliver HDR brachytherapy for the treatment of skin surface lesions. This technique focuses a uniform dose of X-ray source radiation to the lesion with the aid of a shielded surface application. The Esteya® Electronic Brachytherapy System (Nucletron BV) and the Xoft® Axxent® Electronic Brachytherapy System (iCAD Inc.) are 2 systems that recently received FDA clearance through the 510(k) process. FDA product code: JAD.

Policy: 
Electronic brachytherapy for the treatment of nonmelanoma skin cancer (see Policy Guidelines section) is considered INVESTIGATIONAL.

Policy Guidelines: 
Coding
Please see the Codes table for details.

Benefit Application 
BlueCard/National Account Issues
State or federal mandates (e.g., FEP) may dictate that certain U.S. Food and Drug Administration (FDA)‒approved biologics may not be considered investigational and, thus, these drugs may be assessed only on the basis of their medical necessity.

Rationale:  
Evidence reviews assess the clinical evidence to determine whether the use of a technology improves the net health outcome. Broadly defined, health outcomes are length of life, quality of life, and ability to function including benefits and harms. Every clinical condition has specific outcomes that are important to patients and to managing the course of that condition. Validated outcome measures are necessary to ascertain whether a condition improves or worsens; and whether the magnitude of that change is clinically significant. The net health outcome is a balance of benefits and harms.

To assess whether the evidence is sufficient to draw conclusions about the net health outcome of a technology, 2 domains are examined: the relevance and the quality and credibility. To be relevant, studies must represent 1 or more intended clinical use of the technology in the intended population and compare an effective and appropriate alternative at a comparable intensity. For some conditions, the alternative will be supportive care or surveillance. The quality and credibility of the evidence depend on study design and conduct, minimizing bias and confounding that can generate incorrect findings. The randomized controlled trial (RCT) is preferred to assess efficacy; however, in some circumstances, nonrandomized studies may be adequate. Randomized controlled trials are rarely large enough or long enough to capture less common adverse events and long-term effects. Other types of studies can be used for these purposes and to assess generalizability to broader clinical populations and settings of clinical practice.

Electronic Brachytherapy for Nonmelanoma Skin Cancer
Clinical Context and Therapy Purpose

The purpose of electronic brachytherapy in patients who have nonmelanoma skin cancer (NMSC) is to provide a treatment option that is an alternative to or an improvement on existing therapies.

The question addressed in this evidence review is: Does the use of electronic brachytherapy improve the net health outcome in patients with NMSC?

The following PICO was used to select literature to inform this review.

Populations
The relevant population of interest is patients with NMSC. Nonmelanoma skin cancer refers to squamous cell carcinoma (SCC) and basal cell carcinoma (BCC). There are other less common types of skin cancer, such as T-cell lymphoma or Merkel cell tumor, which may have specific treatment options that differ from SCC and BCC and may need to be considered on an individual basis.

Interventions
The therapy being considered is electronic brachytherapy. Electronic brachytherapy is a form of radiotherapy delivered locally, using a miniaturized electronic X-ray source rather than a radionuclide-based source. Multiple treatment sessions within a short time period (typically within a month) are required.

Comparators
The following therapies are currently being used: surgery (excision or Mohs surgery), external-beam radiotherapy (EBRT), and standard brachytherapy.

The diagnosis of NMSC involves a detailed review of medical history, a clinical exam, and a skin biopsy. Information from the diagnostic process can assess the risk of recurrence, which informs the choice of treatment. Location and size of the skin cancer are also factors in choosing the treatment strategy. Brachytherapy is considered when lesions are located on anatomic curves or are near critical organs.

Outcomes
The general outcomes of interest are survival, recurrence rates, and treatment-related morbidity. Follow-up to adequately detect NMSC recurrence should be at least 5 years.

Study Selection Criteria
Methodologically credible studies were selected using the following principles:

  • To assess efficacy outcomes, comparative controlled prospective trials were sought, with a preference for RCTs.
  • In the absence of such trials, comparative observational studies were sought, with a preference for prospective studies.
  • To assess long-term outcomes and adverse events, single-arm studies that capture longer periods of follow-up and/or larger populations were sought;
  • Studies with duplicative or overlapping populations were excluded.

Review of Evidence
Systematic Reviews

Lee et al. (2019) published a meta-analysis of 58 studies including 21,371 patients treated with conventional surgical excision (24 studies), Mohs micrographic surgery (MMS; 13 studies), EBRT (19 studies), or high-dose-rate brachytherapy (7 studies) for indolent BCC and SCC of the skin.7 "Good" cosmesis was reported in 81% (95% confidence interval [CI], 70.6% to 89.6%), 74.6% (95% CI, 63% to 84.6%), and 97.6% (95% CI, 91.3% to 100%) of patients treated with conventional excision, EBRT, and brachytherapy, respectively. This was comparable to the 96% "good" cosmesis grade outcome reported in 1 MMS study. The 5-year local recurrence rate for brachytherapy was 2.5% (95% CI, 0.8% to 5.1%), which was comparable to both MMS (1.8%; 95% CI, 1.1% to 2.7%) and conventional excision (2.1%; 95% CI, 1.0% to 3.5%). The authors concluded that interpretation of results may be limited by selection bias and subjective and heterogeneous cosmesis grading systems, warranting further prospective, comparative studies.

Delishaj et al. (2016) published a systematic review of studies on high-dose rate brachytherapy, including electronic brachytherapy, for the treatment of NMSC.8 A literature review conducted through May 2019 identified 10 case series with sample sizes of 20 patients or more that reported on nonoverlapping patients. Findings were reported for 1870 patients (N = 1870 lesions). Most lesions (65%) were BCC and the second largest group (35%) was SCC. Reviewers did not pool study findings, reporting that the rates of local control ranged from 83% to 100%. After a median follow-up ranging from 9 months to 10 years, recurrence rates ranged from 0% to 17%. Seven of the 10 studies reported recurrence rates of less than 5%, 2 had recurrence rates of 8% to 9%, and 1 study had a recurrence rate of 17%. The 2 studies with recurrence rates in the 8% to 9% range used Leipzig applicators and the study with a 17% recurrence rate used high-dose rate brachytherapy with surface applicators or custom-made surface molds.

Prospective Cohort Study
Patel et al. (2017)9 published preliminary results from a multi-center prospective matched pair cohort study (NCT03024866) comparing clinical outcomes of NMSC treated with electronic brachytherapy or MMS. Patients from 4 treatment centers who had already received treatment for NMSC with electronic brachytherapy and met eligibility criteria were invited to participate. A retrospective chart review was used to individually match patients with patients who had received MMS for NMSC based on patient age (± 15 years), lesion size, type and location, and treatment dates. All MMS-treated subjects treated in the same time-frame were considered for matching and the final pair was selected based on the closest match of demographics and lesion characteristics. A total of 369 patients were included for study representing 208 matched lesion pairs. Additional eligibility criteria included:

  • Completion of electronic brachytherapy or MMS for NMSC ≥ 3 years prior.
  • Age > 40 yrs.
  • Diagnosis of SCC or BCC.
  • Cancer stage 0 to 2.

Exclusion criteria included:

  • Target area adjacent to burn scar.
  • Surgical resection of the cancer prior to electronic brachytherapy.
  • Presence of actinic keratosis.
  • Known metastatic disease.

Patients were evaluated for follow-up at 2.3 to 5.0 years post-treatment. Treatment with electronic brachytherapy was performed with a miniature, high dose rate electronic X-ray source using standard surface applicators. A dose of 40.0 Gy in 8 fractions (5 Gy twice weekly) was used to delivered to a depth of 2 to 3 mm but in some cases a customized dose, depth, or schedule was used. Mohs micrographic surgery was performed by clinicians according to guidelines of the American College of Mohs Surgery. Matching of patients on lesion characteristics was based on the histopathology of BCC or SCC, cancer staging (Stage 0, Stage 1, Stage 2), size (≤ 1 cm, > 1 cm and ≤ 2 cm, > 2 cm and ≤ 3 cm), and location (head, ear, eyelid, face/neck, lip, scalp, nose, torso, lower extremity, upper extremity). The mean follow-up length was 3.3 years for the electronic brachytherapy group and 3.5 years for the MMS group. The primary outcome was absence of NMSC recurrence at follow-up. Secondary outcomes included late toxicities, cosmetic outcomes, and patient satisfaction with treatment. All patients completed all evaluations.

The main characteristics and results are summarized in Table 1.

Table 1. Prospective Cohort Study of Electronic Brachytherapy for Nonmelanoma Skin Cancer9

Population N MFU, years (median; range) Treatment Outcomes      
Patients receiving EBT for NMSC 188   EBT        
Lesions receiving EBT for NMSC (number of lesions, %) 208 3.3 ± 0.4
(3.2; 2.6 to 4.3)
EBT Absence of Local Recurrence at Follow-Up (number of lesions, %, 95% CI) Cosmesis Grade at Follow-Up (number of lesions, %, 95% CI)a Long-term Toxicities Present at Follow-Up (number of lesions, %) Results of Patient Satisfaction Questionnaire at Follow-Up (mean ± SD; median, [10 to 60])b
  • Lesions with BCC (113, 54.3%)
  • Lesions with SCC (95, 45.7%)
208 3.3 ± 0.4
(3.2; 2.6 to 4.3)
EBT 207 (99.5%, 97.4 to 100%) Clinician Cosmesis Grade
  • Excellent/Good (203, 97.6%, 94.5 to 99.2%)
  • Excellent (133, 63.9%)
  • Good (70, 33.7%)
  • Fair (1, 0.5%)
  • Poor (4, 1.9%)
Subject Cosmesis Grade
  • Excellent (140, 67.3%)
  • Good (48, 23.1%)
  • Fair (15, 7.2%)
  • Poor (5, 2.4%)
No changes, relatively invisible scar (138, 66.7%)

Late toxicities:
  • Hypopigmentation (124, 59.6%)
  • Hyperpigmentation (11, 5.3%)
  • Erythematous scar (6, 2.9%)
  • Telangiectasia (65, 31.4%)
  • Hair loss (8, 3.9%)
  • Fibrosis (3, 1.4%)
  • Atrophy (12, 5.8%)
  • Loss of subcutaneous tissue (7, 3.4%)
  • Hypertrophy (excessive fibrosis) or keloid (0, 0%)
  • Poor healing, ulceration, erosion (4, 1.9%)
54.0 ± 9.0; 58.0
Individual Questions
  • Treatments were convenient (4.3 ± 1.1)
  • Satisfied with how well treatment worked (4.5 ± 1.1)
  • Satisfied with appearance of the treated area (4.4 ± 1.0)
  • If another cancer, would use same treatment (4.1 ± 1.4)
  • Have not had any skin problems with treated area (4.5 ± 1.2)
  • Since treatment, frustrated about appearance of treated site (4.5 ± 1.1)
  • Since treatment, embarrassed about appearance of treated site (4.6 ± 0.9)
  • Since treatment, depressed about appearance of treated site (4.5 ± 1.1)
  • Treatment prevented me from participating in daily activities (4.6 ± 0.9)
  • Treatment made it hard to work or do what I enjoy (4.7 ± 0.7)
  • Would recommend treatment to others (4.4 ± 1.3)
  • Always followed instructions related to care of treated area (4.9 ± 0.4)
Patients receiving MMS for NMSC 181 --- MMS Outcomes      
Lesions receiving MMS for NMSC (number of lesions, %) 208 3.5 ± 0.5
(3.4; 2.3 to 5.0)
MMS Absence of Local Recurrence at Follow-Up (Number of lesions, %, 95% CI) Cosmesis Grade at Follow-Up (Number of lesions, %, 95% CI)a Long-term Toxicities Present at Follow-Up (Number of lesions, %) Results of Patient Satisfaction Questionnaire at Follow-Up (mean ± SD; median, [10 to 60])b
  • Lesions with BCC (113, 54.3%)
  • Lesions with SCC (95, 45.7%)
208 3.5 ± 0.5
(3.4; 2.3 to 5.0)
MMS 208 (100%, 98.2 to 100%) Clinician Cosmesis Grade
  • Excellent/Good (199, 95.7%, 92.0 to 98.0%)
  • Excellent (142, 68.3%)
  • Good (57, 27.4%)
  • Fair (9, 4.3%)
  • Poor (0, 0.0%)
Subject Cosmesis Grade
  • Excellent (148, 71.1%)
  • Good (50, 24.0%)
  • Fair (10, 4.8%)
  • Poor (0, 0.0%)
No changes, relatively invisible scar (143, 68.8%)

Late toxicities:
  • Hypopigmentation (109, 52.4%)
  • Hyperpigmentation (4, 1.9%)
  • Erythematous scar (15, 7.2%)
  • Telangiectasia (23, 11.1%)
  • Hair loss (7, 3.4%)
  • Fibrosis (2, 1%)
  • Atrophy (9, 4.3%)
  • Loss of subcutaneous tissue (6, 2.9%)
  • Hypertrophy (excessive fibrosis) or keloid (3, 1.4%)
  • Poor healing, ulceration, erosion (0, 0.0%)
56.0 ± 5.3; 59.0
  • Treatments were convenient (4.7 ± 0.6)
  • Satisfied with how well treatment worked (4.8 ± 0.5)
  • Satisfied with appearance of the treated area (4.6 ± 0.7)
  • If another cancer, would use same treatment (4.6 ± 0.7)
  • Have not had any skin problems with treated area (4.7 ± 0.6)
  • Since treatment, frustrated about appearance of treated site (4.6 ± 1.0)
  • Since treatment, embarrassed about appearance of treated site (4.7 ± 0.7)
  • Since treatment, depressed about appearance of treated site (4.6 ± 0.8)
  • Treatment prevented me from participating in daily activities (4.6 ± 0.9)
  • Treatment made it hard to work or do what I enjoy (4.6 ± 0.8)
  • Would recommend treatment to others (4.7 ± 0.7)
  • Always followed instructions related to care of treated area (4.7 ± 0.5)

BCC: basal cell carcinoma; CI: confidence interval; EBT: electronic brachytherapy; MFU: mean follow-up; MMS: Mohs micrographic surgery; NMSC: nonmelanoma skin cancer; SCC: squamous cell carcinoma; SD: standard deviation.
a Standardized scale adapted from Cox et al. (1995).10
b A score of 5 represents the maximum positive or favorable response to each question.

No statistically significant difference was found between electronic brachytherapy (97.6%) and MMS (95.7%) groups for local recurrence absence (p = 1.000). However, 1 recurrence was reported in the EBT group at 1 year post-treatment. No recurrences occurred in the MMS group. No statistically significant differences were noted for secondary endpoints of cosmesis (p = .277) and patient satisfaction with both groups demonstrating predominantly excellent cosmesis grades and high patient satisfaction scores. Late toxicities appeared at similar rates with telangiectiasa being reported slightly more in the electronic brachytherapy versus MMS group (31.4% vs. 11.1%).

A summary of the electronic brachytherapy study relevance limitations is provided in Table 2.

Table 2. Study Relevance Limitations

Study (year) Populationa Interventionb Comparatorc Outcomesd Follow-Upe
Patel et al. (2017)9 2. Rationale for inclusion and exclusion criteria unclear 2. Version used unclear   6. Clinically significant difference not supported 1. Not sufficient duration for benefit


The study limitations stated in this table are those notable in the current review; this is not a comprehensive gaps assessment.
a Population key: 1. Intended use population unclear; 2. Clinical context is unclear; 3. Study population is unclear; 4. Study population not representative of intended use
b Intervention key: 1. Not clearly defined; 2. Version used unclear; 3. Delivery not similar intensity as comparator; 4. Not the intervention of interest
c Comparator key: 1. Not clearly defined; 2. Not standard or optimal; 3. Delivery not similar intensity as intervention; 4. Not delivered effectively
d Outcomes key: 1. Key health outcomes not addressed; 2. Physiologic measures, not validated surrogates; 3. No CONSORT reporting of harms; 4. Not established and validated measurements; 5. Clinical significant difference not prespecified; 6. Clinical significant difference not supported
e Follow-Up key: 1. Not sufficient duration for benefit; 2. Not sufficient duration for harms
A summary of the electronic brachytherapy study design and conduct limitations is provided in Table 3.

Table 3. Study Design and Conduct Limitations

Study (year) Allocationa Blindingb Selective Reportingc Data Completenessd Powere Statisticalf
Patel et al. (2017)9 3. Allocation concealment unclear in matching procedure 3. Outcome assessed by treating physician 2,3. Evidence of selective reporting and publication 5. Unclear whether patients with metastatic disease should be excluded or whether age exclusion is clinically relevant 1,2. Power calculations not reported for primary outcome

 
The study limitations stated in this table are those notable in the current review; this is not a comprehensive gaps assessment.
a Allocation key: 1. Participants not randomly allocated; 2. Allocation not concealed; 3. Allocation concealment unclear; 4. Inadequate control for selection bias
b Blinding key: 1. Not blinded to treatment assignment; 2. Not blinded to treatment outcome; 3. Outcome assessed by treating physician
c Selective Reporting key: 1. Not registered; 2. Evidence of selective reporting; 3. Evidence of selective publication
d Data Completeness key: 1. High loss to follow-up or missing data; 2. Inadequate handling of missing data; 3. High number of crossovers; 4. Inadequate handling of crossovers; 5. Inappropriate exclusions; 6. No intent to treat analysis (per protocol for non-inferiority trials)
e Power key: 1. Power calculations not reported; 2. Power not calculated for primary outcome; 3. Power not based on clinically important difference
f Statistical key: 1. Analysis is not appropriate for outcome type: (a) continuous; (b) binary; (c) time to event; 2. Analysis is not appropriate for multiple observations per patient; 3. Confidence intervals and/or p values not reported; 4. Comparative treatment effects not calculated

Major limitations of this study included the presence of selective publication and lack of blinding as patients were clinically evaluated for follow-up by the physician who had administered electronic brachytherapy or MMS. The study is registered but result submissions have been canceled twice and have not been submitted as of January 2019. Since some patients received customized treatments, all intervention characteristics are unclear. Eligibility and exclusion criteria seemed to introduce bias with regard to age and low tumor stage. No statistically significant outcomes were reported for the use of electronic brachytherapy compared to MMS in NMSC.

Case Series
Evidence also includes uncontrolled studies. The main characteristics and results of published case series are summarized in Table 4.

Table 4. Case Series of Electronic Brachytherapy for Nonmelanoma Skin Cancer

Study Population N MFU, mo Treatment Outcomes
          Recurrence Toxicity, %
Pellizzon et al. (2020)11 Basal or squamous cell carcinoma 71 42.8
  • Leipzig applicator
  • Total dose: 28 to 55 Gy in 7 to 22 fractions
6.9% Acute:
  • Grade 1 to 2 = 100
  • Grade 3 = 8.9
Late:
  • Grade 3 = 3.9
  • Grade 4 = 0
Paravati et al. (2015)12 Basal, squamous, or basosquamous cell carcinoma 127 16.1
  • Axxent Xoft system
  • Total dose: 40 Gy in 8 fractions delivered 2 times weekly
1.2%c(2/154) Acute:
  • Grade 0 to 1 = 53
  • Grade 2 = 34.4
  • Grade 3 = 13
Late:
  • Grade 0 to 1 = 94
  • Grade 2 = 6
Delishaj et al. (2015)13 Nonmelanoma skin cancer 39 12
  • Valencia applicator
  • Total dose: 40 Gy in 8 fractions
0% Acute:
  • Grade 1 = 58
  • Grade 2 = 5
Late:
  • Grade 1 = 19
  • Grade 2 = 2
Tormo et al. (2014)14 Basal cell carcinoma 32 47
  • Valencia applicator
  • Total dose: 42 Gy in 6 to 7 fractions
3.1%
  • Grade 1 = NR
  • Grade 2 = 0
  • Grade 3 = 0
Bhatnagar et al. (2013)1;Bhatnagar & Loper (2010)15,a Nonmelanoma skin cancer 122 10.0
  • Axxent Xoft system
  • Total dose: 40 Gy in 8 fractions delivered twice weekly
0%
  • Grade 1 = 11
  • Grade 2 = 13
  • Grade 3 = 0
Gauden et al. (2013)16 Small nonmelanoma skin cancers 200 66b
  • Leipzig applicator
  • Total dose: 36 Gy in 12 fractions delivered daily
2%c(4/236)
  • Grade 1 = 71
  • Grade 2 = 34
  • Grade 3 = 0
Giux et al. (2000)17 Basal or squamous cell carcinoma 136 60
  • Brock applicator
  • Total dose: 60 to 65 Gy in 33 to 36 fractions
2.2% NR ("no severe complications")


Gy: gray; MFU: mean follow-up; NR: not reported.
a Overlapping case series; results from larger, more recent publication reported.
b Median.
c Calculated based on number lesions not patients.

The largest series was published by Gauden et al. (2013) and included 200 patients with 236 lesions (121 basal cell, 115 squamous cell).16 Brachytherapy was the primary treatment modality in 69% of the lesions, while in the remaining 31% (74/236) brachytherapy was a follow-up treatment to surgery when there were positive margins. Outcomes included treatment efficacy, as measured by local recurrence rate, skin toxicity measured using Radiation Therapy Oncologic Group criteria, and cosmetic outcome using the Radiation Therapy Oncologic Group Cosmesis Scale. After a median follow-up of 66 months, there were recurrences in 2% (4/236) of treated lesions. Cosmetic outcome was judged to be excellent or good in 88% (208/236) of treated lesions. Grade 1 skin toxicity was common (71% of treated lesions); grade 2 toxicity was less common (34%); and no instances of grade 3 or higher toxicities were noted. Late hypopigmentation of treated skin was reported in 5.5% (13/236) of treated lesions.

Bhatnager (2013) published a case series using a commercially available device (Axxent eBx System).The series included 122 patients with 171 nonmelanoma skin lesions. Most patients had either BCC (53%) or SCC (41%); 10 (5.8%) patients had other types of cancer. Outcome measures included recurrence rates, adverse events using version 3.0 of the Common Terminology Criteria for Adverse Events, and cosmetic results using a standardized Cosmesis Scale. After a mean 10-month follow-up, there were no local recurrences. Dermatitis and pruritus were common early adverse events, occurring in 83% and 18% of the treated lesions, respectively. Skin hypopigmentation was the most common late adverse event, occurring in 10.9% of lesions at 1 year. Other late complications included rash (6.5%), alopecia (2.2%), and dry desquamation (2.2%). All patients had their cosmetic outcomes rated as good or excellent.

Summary of Evidence
For individuals who have NMSC who receive electronic brachytherapy, the evidence includes 2 systematic reviews, a prospective cohort study, and case series. Relevant outcomes are overall survival, disease-specific survival, change in disease status, and treatment-related morbidity. No controlled trials were identified that have compared electronic brachytherapy with alternative treatment options. A 2016 systematic review of case series found local control rates ranging from 83% to 100% and recurrence rates ranging from 0% to 17%. In most studies, the recurrence rate was less than 5%. A 2019 meta-analysis reported brachytherapy cosmesis grades and 5-year local control rates that were comparable to both MMS and conventional excision. Preliminary results from a prospective matched pair cohort study reported no statistically significant difference in outcomes for the use of electronic brachytherapy compared to MMS in NMSC, but confidence in these findings is low due to study design and conduct limitations. In the absence of randomized controlled studies, conclusions cannot be drawn about the efficacy and safety of electronic brachytherapy compared with other treatments for NMSC. Controlled trials are needed in defined populations that compare electronic brachytherapy with alternatives, specifically other forms of radiotherapy or surgical approaches. The evidence is insufficient to determine that the technology results in an improvement in the net health outcome.

The purpose of the following information is to provide reference material. Inclusion does not imply endorsement or alignment with the evidence review conclusions.

Practice Guidelines and Position Statements
Guidelines or position statements will be considered for inclusion in "Supplemental Information" if they were issued by, or jointly by, a U.S. professional society, an international society with U.S. representation, or National Institute for Health and Care Excellence (NICE). Priority will be given to guidelines that are informed by a systematic review, include strength of evidence ratings, and include a description of management of conflict of interest.

American Academy of Dermatology
In 2018, the American Academy of Dermatology published guidelines on the management of basal cell carcinoma4,and the management of squamous cell carcinoma.18 Electronic brachytherapy was rated as a C recommendation, with a level of evidence of II and III. By comparison, surgery, cryosurgery, topical therapies, and photodynamic therapies are rated as A and B recommendations.

American Brachytherapy Society
The American Brachytherapy Society issued a consensus statement on electronic brachytherapy following a literature review focused on trials, prospective studies, multi-institutional series, and single institution reports addressing clinical outcomes and toxicities.19 Due to a lack of comparative data to traditional treatments and limited long-term follow-up, prospective studies with a larger number of patients undergoing electronic brachytherapy for nonmelanoma skin cancer are recommended. At this time, the statement recommends that treatment with electronic brachytherapy in this patient population should be performed in the context of a clinical registry or trial.

American Society for Radiation Oncology
The American Society for Radiation Oncology (ASTRO) issued clinical practice guidelines regarding definitive and postoperative radiation therapy for basal and squamous cell cancers of the skin.20 Key questions were addressed by a systematic literature review and recommendations were developed via consensus with a modified Delphi approach. Consensus recommendations for specific dose-fractionation schemes are detailed for the definitive and post-operative settings. The guideline also states that appropriate use of any of the 4 major radiation modalities, including electronically-generated low energy sources such as electronic brachytherapy, result in similar local control and cosmetic outcomes. Therefore, "the decision of which modality and fractionation scheme to use should be based on both tumor characteristics (e.g., shape, contour, depth, and location) and normal tissue considerations."

National Comprehensive Cancer Network
The National Comprehensive Cancer Network guidelines on basal cell carcinoma (v.2.2022 )21 and squamous cell skin cancer (v.2.2022)22 both contain the following statement on brachytherapy: "There is insufficient long-term efficacy and safety data to support the routine use of electronic surface brachytherapy."

U.S. Preventive Services Task Force Recommendations
Not applicable.

Ongoing and Unpublished Clinical Trials
Some currently ongoing and unpublished trials that might influence this review are listed in Table 5.

Table 5. Summary of Key Ongoing Trials

NCT No. Trial Name Planned Enrollment Completion Date
Ongoing      
NCT02131805 A Multicenter Pilot Study of Electronic Skin Surface Brachytherapy for Cutaneous Basal Cell and Squamous Cell Carcinoma 36 May 2023
Unpublished      
NCT03024866a

Electronic Brachytherapy: A Multi-Center Retrospective-Prospective Matched Pairs Cohort Study to Assess Long Term Clinical Outcomes of Nonmelanoma Skin Cancer Patients Treated with eBx Compared to Nonmelanoma Skin Cancer Patients Treated with Mohs Surgery

500 Jan 2018 (unknown, last update Jan 2017)
NCT01016899a Xoft Electronic Brachytherapy Clinical Protocol for the Primary Treatment of Non-Melanoma Skin Cancer 100 Feb 2018 (unknown; last update Sep 2017)

NCT: national clinical trial.
a Denotes industry-sponsored or cosponsored trial.

References: 

  1. Bhatnagar A. Nonmelanoma skin cancer treated with electronic brachytherapy: results at 1 year. Brachytherapy. Mar-Apr 2013; 12(2): 134-40. PMID 23312675
  2. Madan V, Lear JT, Szeimies RM. Non-melanoma skin cancer. Lancet. Feb 20 2010; 375(9715): 673-85. PMID 20171403
  3. American Academy of Dermatology Association. Skin cancer. Updated April 22, 2022. https://www.aad.org/media/stats-skin-cancer. Accessed May 24, 2022.
  4. Kim JYS, Kozlow JH, Mittal B, et al. Guidelines of care for the management of basal cell carcinoma. J Am Acad Dermatol. Mar 2018; 78(3): 540-559. PMID 29331385
  5. Alam M, Nanda S, Mittal BB, et al. The use of brachytherapy in the treatment of nonmelanoma skin cancer: a review. J Am Acad Dermatol. Aug 2011; 65(2): 377-388. PMID 21496952
  6. Avril MF, Auperin A, Margulis A, et al. Basal cell carcinoma of the face: surgery or radiotherapy? Results of a randomized study. Br J Cancer. 1997; 76(1): 100-6. PMID 9218740
  7. Lee CT, Lehrer EJ, Aphale A, et al. Surgical excision, Mohs micrographic surgery, external-beam radiotherapy, or brachytherapy for indolent skin cancer: An international meta-analysis of 58 studies with 21,000 patients. Cancer. Oct 15 2019; 125(20): 3582-3594. PMID 31355928
  8. Delishaj D, Rembielak A, Manfredi B, et al. Non-melanoma skin cancer treated with high-dose-rate brachytherapy: a review of literature. J Contemp Brachytherapy. Dec 2016; 8(6): 533-540. PMID 28115960
  9. Patel R, Strimling R, Doggett S, et al. Comparison of electronic brachytherapy and Mohs micrographic surgery for the treatment of early-stage non-melanoma skin cancer: a matched pair cohort study. J Contemp Brachytherapy. Aug 2017; 9(4): 338-344. PMID 28951753
  10. Cox JD, Stetz J, Pajak TF. Toxicity criteria of the Radiation Therapy Oncology Group (RTOG) and the European Organization for Research and Treatment of Cancer (EORTC). Int J Radiat Oncol Biol Phys. Mar 30 1995; 31(5): 1341-6. PMID 7713792
  11. Pellizzon ACA, Fogaroli R, Chen MJ, et al. High-dose-rate brachytherapy using Leipzig applicators for non-melanoma localized skin cancer. J Contemp Brachytherapy. Oct 2020; 12(5): 435-440. PMID 33299432
  12. Paravati AJ, Hawkins PG, Martin AN, et al. Clinical and cosmetic outcomes in patients treated with high-dose-rate electronic brachytherapy for nonmelanoma skin cancer. Pract Radiat Oncol. Nov-Dec 2015; 5(6): e659-64. PMID 26432680
  13. Delishaj D, Laliscia C, Manfredi B, et al. Non-melanoma skin cancer treated with high-dose-rate brachytherapy and Valencia applicator in elderly patients: a retrospective case series. J Contemp Brachytherapy. Dec 2015; 7(6): 437-44. PMID 26816500
  14. Tormo A, Celada F, Rodriguez S, et al. Non-melanoma skin cancer treated with HDR Valencia applicator: clinical outcomes. J Contemp Brachytherapy. Jun 2014; 6(2): 167-72. PMID 25097557
  15. Bhatnagar A, Loper A. The initial experience of electronic brachytherapy for the treatment of non-melanoma skin cancer. Radiat Oncol. Sep 28 2010; 5: 87. PMID 20875139
  16. Gauden R, Pracy M, Avery AM, et al. HDR brachytherapy for superficial non-melanoma skin cancers. J Med Imaging Radiat Oncol. Apr 2013; 57(2): 212-7. PMID 23551783
  17. Guix B, Finestres F, Tello J, et al. Treatment of skin carcinomas of the face by high-dose-rate brachytherapy and custom-made surface molds. Int J Radiat Oncol Biol Phys. Apr 01 2000; 47(1): 95-102. PMID 10758310
  18. Kim JYS, Kozlow JH, Mittal B, et al. Guidelines of care for the management of cutaneous squamous cell carcinoma. J Am Acad Dermatol. Mar 2018; 78(3): 560-578. PMID 29331386
  19. Tom MC, Hepel JT, Patel R, et al. The American Brachytherapy Society consensus statement for electronic brachytherapy. Brachytherapy. May 2019; 18(3): 292-298. PMID 30497939
  20. Likhacheva A, Awan M, Barker CA, et al. Definitive and Postoperative Radiation Therapy for Basal and Squamous Cell Cancers of the Skin: Executive Summary of an American Society for Radiation Oncology Clinical Practice Guideline. Pract Radiat Oncol. Jan 2020; 10(1): 8-20. PMID 31831330
  21. National Comprehensive Cancer Network (NCCN). NCCN Clinical Practice Guidelines in Oncology: Basal Cell Skin Cancer. Version 2.2022. https://www.nccn.org/professionals/physician_gls/pdf/nmsc.pdf. Accessed May 24, 2022.
  22. National Comprehensive Cancer Network (NCCN). NCCN Clinical Practice Guidelines in Oncology: Squamous Cell Skin Cancer. Version 2.2022. https://www.nccn.org/professionals/physician_gls/pdf/squamous.pdf. Accessed May 24, 2022.

Coding Section 

Codes Number Description
CPT 0394T High-dose rate electronic brachytherapy, skin surface application, per fraction, includes basic dosimetry, when performed.
HCPCS    
ICD-10-CM   Investigational for all relevant diagnoses.
    Codes for basal cell and squamous cell carcinomas of the skin (C44.00-C44.99) are dependent on the anatomic location of the lesion. There are too many to list here so the following codes are just examples.
  C44.211-C44.219 Basal cell carcinoma of skin of ear and external auricular canal code range.
  C44.221-C44.229 Squamous cell carcinoma of skin of ear and external auricular canal code range.
  C44.310-C44.319 Basal cell carcinoma of skin of other and unspecified parts of face code range (includes nose).
  C44.320-C44.329 Squamous cell carcinoma of skin of other and unspecified parts of face code range (includes nose).
  C44.41 Basal cell carcinoma of skin of scalp and neck.
  C44.42 Squamous cell carcinoma of skin of scalp and neck.
ICD-10-PCS   ICD-10-PCS codes are only used for inpatient services. There is no specific ICD-10-PCS code for this procedure — surface application.
Type of Service Oncology  
Place of Service Outpatient  

Procedure and diagnosis codes on Medical Policy documents are included only as a general reference tool for each policy. They may not be all-inclusive.

This medical policy was developed through consideration of peer-reviewed medical literature generally recognized by the relevant medical community, U.S. FDA approval status, nationally accepted standards of medical practice and accepted standards of medical practice in this community, Blue Cross Blue Shield Association technology assessment program (TEC) and other nonaffiliated technology evaluation centers, reference to federal regulations, other plan medical policies, and accredited national guidelines.

"Current Procedural Terminology © American Medical Association. All Rights Reserved" 

History From 2015 Forward     

06/05/2023 Annual review, no change to policy intent. Updating rationale and references.)
06/27/2022 Annual review, no change to policy intent. Updating rationale and references. 

06/01/2021 

Annual review, no change to policy intent. Updating guidelines and coding. 

06/01/2020 

Annual review, no change to policy intent. Updating rationale and references. 

06/04/2019 

Annual review, no change to policy intent. Updating background, rationale and references. 

06/01/2018 

Annual review, no change to policy intent. Updating rationale and references. 

06/06/2017 

Annual review, no change to policy intent. Updating background, description, guidelines, rationale and references. 

06/06/2016 

Annual review, no change to policy intent. Updating guidelines and coding.

12/1/2015

Updated CPT codes with 2016 codes. No change to intent of policy.

06/09/2015

NEW POLICY

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