High dose rate brachytherapy with customized applicators for malignant facial skin lesions

Implementing high-dose rate surface mould brachytherapy for carcinoma of eyelid: a practical approach and weekly review

Surface mould brachytherapy is a conformal radiotherapy technique that can deliver high dose to the target while sparing nearby normal structures, Here, we aim to describe the procedurals details for high-dose rate (HDR) surface mould brachytherapy in sebaceous carcinoma of eyelid in a 54-year old lady. She was hesitant for surgery and any form of invasive intervention like interstitial brachytherapy. So, she was treated with surface mould HDR brachytherapy to a total dose of 52 Gy in 13 fractions at a dose of 4 Gy per fraction delivered twice daily using Iridium-192 isotope with no acute side effects. She was evaluated on a weekly basis for any radiation side effects and now she is disease-free for 6 months post-treatment with only mild dry eye. A detailed step-by-step procedure of surface mould technique, simulation procedure, dose prescription, planning, plan evaluation and treatment has been described in this paper. Surface mould HDR brachytherapy can be safely used as organ preserving modality of treatment for eyelid carcinoma.

Effects of Radiation-Induced Skin Injury on Hyaluronan Degradation and Its Underlying Mechanisms

Radiation-induced skin injury (RISI) is a frequent and severe complication with a complex pathogenesis that often occurs during radiation therapy, nuclear incidents, and nuclear war, for which there is no effective treatment. Hyaluronan (HA) plays an overwhelming role in the skin, and it has been shown that UVB irradiation induces increased HA expression. Nevertheless, to the best of our knowledge, there has been no study regarding the biological correlation between RISI and HA degradation and its underlying mechanisms. Therefore, in our study, we investigated low-molecular-weight HA content using an enzyme-linked immunosorbent assay and changes in the expression of HA-related metabolic enzymes using real-time quantitative polymerase chain reaction and a Western blotting assay. The oxidative stress level of the RISI model was assessed using sodium dismutase, malondialdehyde, and reactive oxygen species assays. We demonstrated that low-molecular-weight HA content was significantly upregulated in skin tissues during the late phase of irradiation exposure in the RISI model and that HA-related metabolic enzymes, oxidative stress levels, the MEK5/ERK5 pathway, and inflammatory factors were consistent with changes in low-molecular-weight HA content. These findings prove that HA degradation is biologically relevant to RISI development and that the HA degradation mechanisms are related to HA-related metabolic enzymes, oxidative stress, and inflammatory factors. The MEK5/ERK5 pathway represents a potential mechanism of HA degradation. In conclusion, we aimed to investigate changes in HA content and preliminarily investigate the HA degradation mechanism in a RISI model under γ-ray irradiation, to consider HA as a new target for RISI and provide ideas for novel drug development.

Hypofractionated radiotherapy for invasive squamous cell carcinoma of the scalp in the elderly: Efficacy and tolerance, preliminary results

PURPOSE

Skin squamous cells carcinomas (SCC) are frequently tumor, especially in the elderly population. Surgical excision is the standard treatment. But for patients suffering large tumor or/with comorbidity, a conservative approach with irradiation can be proposed. The hypofractionated schedule is used to shorten the overall treatment time with same results and without compromising therapeutic outcomes. The aim of this study is to assess the efficacy and tolerance of hypofractionated radiotherapy for invasive SCC of the scalp in elderly.

PATIENTS AND METHODS

We included patients suffering from SCC of the scalp and treated by hypofractionated radiotherapy at the Institut de cancérologie de Lorraine or centre Émile-Durkeim d'Épinal, from January 2019 to December 2021. Characteristics of patients, size of the lesion and side effects were collected retrospectively. Tumor size at 6 months corresponded to the primary endpoint. Toxicity was collected for the secondary endpoint.

RESULTS

Twelve patients with a median age of 85 years old were included. The mean size was 4,5cm with a bone invasion in 2/3 of cases. Radiotherapy was delivered after surgical excision for half of the patient. The dose delivered was 54Gy in 18 daily fractions size. Six months after irradiation: 6/11 patients had no residual lesion, 2/11 had a partial response with a residual lesion of about 1cm. 3 patients presented local recurrence. One patient died within 6 months of radiotherapy because of another comorbidity. In total, 25% had presented a grade 3 acute radiation dermatitis, no grade 4 toxicity.

CONCLUSION

Short term of moderately hypofractionated schedule radiotherapy was a success with complete or partial response for more than 70% of the patients in squamous cell carcinomas. There is no major side effect.

HDR brachytherapy in keratinocyte skin carcinomas - Single center experience with analysis of clinical, dosimetric, and radiobiological factors in acute skin toxicity

PURPOSE

Radiotherapy techniques have been utilized to treat keratinocyte skin carcinoma (KSC). The objective of this study was to report the results of patients with KSC treated with HDR brachytherapy, with a variety of techniques and applicators. A statistical analysis of clinical, radiobiological, and technical factors has been made to analyze those factors related to skin acute toxicity, focused on acute epithelitis G3.

METHODS AND MATERIALS

Between February 2005 and August 2020, 93 patients with 120 histologically proven KSC have been treated in our Institution. BT treatment has been performed using superficial BT/plesiotherapy (Valencia applicator (22%), flaps (48%), customized molds (4%) or interstitial techniques (26%)). The indications of BT were primary/definitive in 38 treatments (32%) or adjuvant/postoperative in 82 (68%). In 14 (17%) of the 82 operated patients a skin graft. Mean comparison t tests were performed for quantitative variables, and percentage comparison Chi2 tests for qualitative. Multivariate binomial logistic regression models were done.

RESULTS

Median follow-up was 36.5 months (range 5-141). Local control was achieved in 110 treatments (92%). Acute toxicity, dermatitis, was G1 7%; G2, 57% and G3 38%. The main factors statistically associated to the appearance of dermatitis G3 were the total dose, the volume treated, and the use of manufactured flaps. The main protective factor against dermatitis G3 was implant of skin graft.

CONCLUSIONS

In KSC BT the use of manufactured flap is accompanied by greater EG3, only with a relationship with the volume of treatment and total dose.

H&N and Skin (HNS) GEC-ESTRO Working Group critical review of recommendations regarding prescription depth, bolus thickness and maximum dose in skin superficial brachytherapy with flaps and customized moulds

The aim of this publication is the assessment of the existing guidelines for non-melanoma skin cancer (NMSC) superficial brachytherapy (BT) and make a critical review based on the existing literature about the maximum dose prescription depth, bolus thickness and maximum skin surface dose (D_max) of the published clinical practice. A systematic review of NMSC superficial BT published articles was carried out by the GEC-ESTRO Head & Neck and Skin (HNS) Working Group (WG). 10 members and 2 external reviewers compared the published clinical procedures with the recommendations in the current guidelines and examined the grade of evidence. Our review verified that there is a large variation among centres with regards to clinical practice in superficial BT and identified studies where published parameters such as maximum dose prescription depth, bolus thickness and D_max exceed the constraints recommended in the guidelines, while showing excellent results in terms of local control, toxicity and cosmesis. This review confirmed that current recommendations on skin superficial BT do not include published experience on tumours treated with superficial BT that require dose prescription depth beyond the recommended 5mm under the skin surface and that the existing literature does not provide sufficient evidence to relate dosimetry of superficial BT to patient reported outcome measures. The GEC-ESTRO HNS WG considers acceptable to prescribe superficial BT dose at a depth above 5mm beyond the skin surface, and modify the bolus thickness to optimize the treatment plan and adjust the acceptable maximum dose on the skin surface, all pending clinical situation.

The State of the Art of Radiotherapy for Non-melanoma Skin Cancer: A Review of the Literature

Due to the general aging population and the fashion trend of sun exposure, non-melanoma skin cancer (NMSC) is rising. The management of NMSC is difficult and necessitates a multidisciplinary team (i.e., pathologists, dermatologists, medical oncologists, surgeons, and radiation oncologists). When surgery is not an option or will cause unacceptably functional morbidity, radiation therapy (RT) may be a preferable tissue-preserving option. Whether used alone or in conjunction with other treatments, RT has been shown to be quite effective in terms of cosmetic results and local control. Contact hypofractionated RT, brachytherapy, and electronic brachytherapy are all promising new treatments. However, rigorous, randomized trials are missing, explaining the disparity in dose, fractionation, and technique recommendations. Therefore, it is essential that interdisciplinary teams better understand RT modalities, benefits, and drawbacks. Our review will provide the role and indications for RT in patients with NMSC.

High-dose-rate plesiotherapy with customized molds in non-melanoma skin cancer: efficacy and safety at 10 years-single institution experience

Purpose

Our center adopted high-dose-rate brachytherapy with surface applicators (plesiotherapy) in 2008, creating custom molds to treat irregular areas. This study describes the efficacy and safety outcomes after extensive follow-up in the patients.

Methods/patients

We planned the treatment using two computed tomography (CT) scans: the first to delineate the lesion and the second after placing the thermoplastic mold. Fusing the two CT images enables planning of the target volume and pinpointing, where the catheters are in the mold.

Results

Seventy patients received plesiotherapy, either exclusively or following excision in patients with risk factors for recurrence. Those receiving plesiotherapy alone showed a complete response rate of 95.8%, and recurrences occurred in 5.7% at a mean follow-up of 96.2 months. Chronic toxicity appeared in 26.6% of patients, but severity was limited to grade 1 or 2.

Conclusions

High-dose-rate brachytherapy with customized molds yields a high rate of complete response, with long-term recurrence rates in line with similar studies and an acceptable toxicity rate.

Acute and late complications and toxicities of skin brachytherapy

Skin cancer is the most prevalent malignancy, and its incidence is rising. Surgery is the primary treatment, however, morbidity of surgical resection in certain parts of the body warrant alternate treatment options such as radiation therapy. Complex topology of the skin can pose a challenge for treatment with photon and electron external beam radiotherapy techniques. Brachytherapy can be an attractive radiotherapy technique for these regions. Furthermore, brachytherapy results in lower dose to the underlying deep organs. The goal of this manuscript is to provide a brief overview of the role of brachytherapy for skin malignancies and to outline potential acute and long-term toxicities.

Non-melanoma Skin Cancer Treated by Contact High-dose-rate Radiotherapy (Brachytherapy): A Mono-institutional Series and Literature Review

BACKGROUND/AIM

Non-melanoma skin cancers (NMSC) are the most common neoplasms worldwide and their incidence has been proven to increase in recent years and their treatment should aim at cancer cure as well as cosmetic and functional results. The aim of the study was to report the results of our mono-institutional series of high-dose-rate radiotherapy (cHDR-RT) in NMSC, based on a homogenous technique and two different treatment schedules.

PATIENTS AND METHODS

All patients affected by NMSC who were consecutively evaluated and treated at our Interventional Oncology Center from October 2018 to August 2020, were included. Patients underwent cHDR-RT using flap applicators and remotely afterloaded Ir-192 sources.

RESULTS

Overall, 51 patients were treated for a total of 67 lesions. Local control (LC) and disease-specific survival (DSS) were 94.0% and 100%, respectively. Grade 1, grade 2, grade 3 and grade 4 acute toxicity rates were 24.6%, 3.5%, 3.5%, and 0.0%, respectively. The cosmetic results were graded as excellent/good, fair, and poor in 73.7%, 19.3%, and 7.0%.

CONCLUSION

cHDR-RT of NMSC is an effective alternative to surgery due to excellent outcomes both in terms of local control and aesthetic results especially in the face.

Tumor control and cosmetic outcome of weekly iridium-192 high-dose-rate brachytherapy for nonmelanoma skin cancers in the elderly

PURPOSE

Radiotherapy with high-dose-rate (HDR) brachytherapy is used to treat nonmelanoma skin cancers. We retrospectively analyzed a hypofractionated regimen to assess its safety and efficacy in elderly patients ≥70 years.

METHODS AND MATERIALS

Forty-eight patients with 67 lesions treated since 2016 with catheter-based iridium-192 HDR brachytherapy using a custom mold or three-dimensional-printed applicator met inclusion criteria. Treatment was 36 Gy in six weekly fractions. Local and locoregional control were assessed with Kaplan-Meier curves. Acute and late toxicity were graded as per Common Terminology Criteria for Adverse Events, version 5. Cosmesis was defined as "excellent" (indistinguishable from untreated skin), "good" (minimal changes), or "poor" (extensive changes). Univariate analyses were performed.

RESULTS

Median age was 85.7 years, and 21 were female. Durable local control occurred in 63 lesions (94.0%), giving estimated local control of 100% at 6 months, 95.1% at 1 year, and 88.8% at 2 years. No factors were predictive of local control on univariate analysis. All experienced acute toxicity that ultimately resolved: 28.4% Grade 2 and 4.5% Grade 3. Larger treatment volume receiving ≥36 Gy was associated with increased Grade ≥2 acute toxicity. Patients experienced late Grade 2 and late Grade 4 toxicity after 6.5% treatments each. Younger age was associated with increased Grade ≥2 late toxicity. "Good" or better cosmesis occurred in 93.2%, and "poor" cosmesis was associated with lower extremities and larger lesions.

CONCLUSIONS

Hypofractionated HDR brachytherapy using 36 Gy in six weekly fractions is associated with satisfactory locoregional control and cosmesis with minimal risk of severe acute or late toxicities.

High-dose-rate brachytherapy for non-melanoma skin cancer using tailored custom moulds - a single-centre experience

AIM OF THE STUDY

The aim of this retrospective study was to analyse tumour control, toxicity, and aesthetic outcome of patients affected by non-melanoma skin cancer (NMSC) treated with 192 Ir high-dose-rate (HDR)-brachytherapy (BT) at the Division of Radiotherapy, University of Pisa.

MATERIAL AND METHODS

From January 2014 to December 2019 we treated 37 patients (median age 79 years; range 31-91 years) affected by NMSC, with the following histological subtypes: 62.2% basal cell carcinoma and 37.8% squamous cell carcinoma. We analysed 40 lesions with a depth ≤ 5 mm, located in 40.0% scalp, 17.5% nose, 25.0% face, and 17.5% ear, all treated with 192 Ir-based HDR-BT, using tailored custom moulds, with a median of 5 catheters (range, 1-9) spaced 1 cm apart. The most common fractionation scheme was 40 Gy in 8 daily fractions; the biological effective dose was 60 Gy.

RESULTS

The median follow-up was 25 months (range, 3-70 months). The 2-year local control rate was 90%. Common terminology criteria for adverse event (CTCAE vs. 5.0) G1 toxicities were dermatitis (52%), pain (25%), and ulceration (22%). The only G2 acute toxicities were dermatitis and ulceration. The most common G1 late toxicities were fibrosis (17%), atrophy (15%), and hypopigmentation (12%). No G3 or higher acute or late toxicity was reported. Excellent cosmetic results were observed in 65.0% of the lesions; only 1 case (2.5%) reported a poor cosmetic result.

CONCLUSIONS

Surface mould HDR-BT is a safe, effective, and well tolerated treatment modality for NMSC and can be considered a good alternative, especially for elderly patients who are often unfit for surgery.

High-dose-rate brachytherapy for facial skin cancer: Outcome and toxicity assessment for 71 cases

PURPOSE

In France, the reference technique for skin cancer was low-dose-rate brachytherapy (BT) delivered via iridium wire. At the end of their commercialization in 2015 we have replaced them by high-dose-rate (HDR) BT via interstitial catheters. We assessed efficacy and tolerance as soon as this technique was implemented.

METHODS AND MATERIALS

Patients received 7 Gy on the first day, followed by 8 × 4 Gy over the next 4 days for exclusive BT and 9 × 4 Gy over 5 days for post-operative BT.

RESULTS

Sixty-six patients of median age 81 years received a total of 58 primary BT and 13 post-operative BT for non-melanoma facial skin cancers. Implantation was without difficulty. Median follow up was 15.3 months. Two patients died of intercurrent diseases before first follow up. For the others, 98.5% showed complete response and 3% local recurrence after a median of 20.5 months. Four patients had grade 3 acute dermatitis and three patients had grade 3 mucositis. All the Grade 3 toxicities were resolved within 3 months. A late significant hypopigmentation occurred in 4 patients.

CONCLUSIONS

HDR BT is efficient and well-tolerated with good cosmetic results. HDR catheters are similar with iridium wires in terms of technical difficulty.

HDR brachytherapy with individual epithetic molds for facial skin cancer: techniques and first clinical experience

BACKGROUND

Facial skin cancer lesions in close proximity to critical organs require further development of radiotherapeutic techniques for highly conformal treatment, especially when treating elderly frail patients. We report on our treatment technique and first clinical experience for patients with perinasal/periorbital skin cancer treated with individualized epithetic mold high-dose-rate brachytherapy (BRT).

METHODS

From January 2019, patients with complex shaped or unfavorably located skin cancer not eligible for surgery or external beam radiotherapy (RT) were screened for mold-based BRT. Six patients were identified. Toxicity and clinical response were documented during therapy and posttreatment follow-up.

RESULTS

Median patient age was 80 years (74-92 years). Median prescription dose was 42 Gy (range, 33-44 Gy) delivered in once-daily fractions of 3 or 4 Gy. Two patients had treatment interruptions caused by acute conjunctivitis grade 2 and a nontreatment-related cardiac event, respectively. At a median follow-up of 335 days (96-628 days), no ≥ grade 2 late toxicity was documented with all patients showing complete clinical response.

CONCLUSIONS

High-dose-rate BRT with individualized epithetic molds for perinasal/periorbital skin cancer is a well-tolerated and safe treatment option for patients not eligible for primary surgery or definitive external beam RT because of comorbidities or tumor location.

Novel method of combined photon beam radiotherapy and brachytherapy for treatment of extensive advanced scalp squamous cell carcinoma

Radiotherapy of extensive malignant scalp lesions has always been a challenge for radiation oncologists considering the proximity of critical structures. We treated a 39-year-old patient with extensive scalp squamous cell carcinoma with application of adjuvant concurrent chemoradiation and external beam radiation therapy (EBRT), followed by high-dose-rate (HDR) surface brachytherapy boost using an exclusively designed mould, and assessed the radiation dose reaching planning target volume, brain, and optic structures. Comparison between conventional planning with sole EBRT and combined treatment planning with EBRT and brachytherapy, assured the use of the latter treatment to avoid high radiation doses from reaching critical organs at risk without compromising the required dose for planning target volume.

Development of a method for treating lower-eyelid carcinomas using superficial high dose rate brachytherapy

In this study, a method was developed for delivering high dose rate (HDR) brachytherapy treatments to basal cell carcinomas (BCCs) as well as squamous cell carcinomas (SCCs) of the lower eyelid via superficial catheters. Clinically-realistic BCC/SCC treatment areas were marked in the lower-eyelid region on a head phantom and several arrangements of catheters and bolus were trialled for treating those areas. The use of one or two catheters of different types was evaluated, and sources of dosimetric uncertainty (including air gaps) were evaluated and mitigated. Test treatments were planned for delivery with an iridium-192 source, using the Oncentra Brachy treatment planning system (Elekta AB, Stockholm, Sweden). Dose distributions were evaluated using radiochromic film. The proposed method was shown to be clinically viable, for using superficial HDR brachytherapy to overcome anatomical difficulties and create non-surgical treatments for BCC and SCC of the lower eyelid.

The American Brachytherapy society consensus statement for skin brachytherapy

PURPOSE

Keratinocyte carcinoma (KC, previously nonmelanoma skin cancer) represents the most common cancer worldwide. While surgical treatment is commonly utilized, various radiation therapy techniques are available including external beam and brachytherapy. As such, the American Brachytherapy Society has created an updated consensus statement regarding the use of brachytherapy in the treatment of KCs.

METHODS

Physicians and physicists with expertise in skin cancer and brachytherapy created a consensus statement for appropriate patient selection, data, dosimetry, and utilization of skin brachytherapy and techniques based on a literature search and clinical experience.

RESULTS

Guidelines for patient selection, evaluation, and dose/fractionation schedules to optimize outcomes for patients with KC undergoing brachytherapy are presented. Studies of electronic brachytherapy are emerging, although limited long-term data or comparative data are available. Radionuclide-based brachytherapy represents an appropriate option for patients with small KCs with multiple techniques available.

CONCLUSIONS

Skin brachytherapy represents a standard of care option for appropriately selected patients with KC. Radionuclide-based brachytherapy represents a well-established technique; however, the current recommendation is that electronic brachytherapy be used for KC on prospective clinical trial or registry because of a paucity of mature data.

Surface Mould Brachytherapy for Skin Cancers: The British Columbia Cancer Experience

Purpose To report on skin tumor treatment with surface mould brachytherapy at our institution. Methods This was a retrospective review for all patients with skin tumors treated using Ir-192 high dose rate (HDR) surface mould brachytherapy from January 1, 2010 to December 31, 2017 in British Columbia. We identified 65 lesions (59 patients). Median age at diagnosis was 83 (range = 45-97). The majority were basal cell (54%, n = 35) or squamous cell carcinomas (31%, n = 20). Most lesions were located in the head and neck region. The most commonly used RT dose was 40 Gy/10 fractions; all patients had individualized CT-based planning. Results The two-year overall survival (OS) was 77.6% and two-year progression-free survival (PFS) was 71.5%. Most deaths were from unrelated causes. Response was assessed in clinic 2-4 months post-treatment. Our complete response (CR) rate was 96.8%, with partial response in two patients; two patients could not be assessed for response. We report a two-year local control (LC) rate of 84.9%, and local recurrence in five patients. The procedure was well tolerated, with no grade 3-5 acute or late toxicities. There was one case of grade 2 radionecrosis (Common Terminology Criteria for Adverse Events (CTCAE) v. 4.03). The 100% isodose line median depth was 0.5 cm, and median surface dose = 126.5%. The median V90 = 92.3%. Conclusion Surface mould brachytherapy for skin tumors is a safe and effective modality, with excellent response rates. It is well-tolerated and a non-invasive option for elderly patients with comorbidities.

Prognostic factors for cats with squamous cell carcinoma of the nasal planum following high-dose rate brachytherapy

OBJECTIVES

The aim of the study was to investigate retrospectively the prognostic impact of variables such as sex, neuter status, breed, age, number of lesions, location and size of the tumour, tumour extension beyond the nasal planum, ulceration and lymph node status, among others, in a population of cats treated with high-dose rate brachytherapy.

METHODS

This study reviews the outcome of 58 cats with cytologically and/or histologically confirmed squamous cell carcinoma of the nasal planum, treated at the Clinic Alliance (Bordeaux, France) with high-dose rate brachytherapy from 2010-2016. The total radiation dose delivered was 30 Gy, administered in two different schedules: five fractions of 6 Gy for a period of 4 days (Tuesday-Friday) or four fractions of 7.5 Gy for a period of 3 days (Tuesday- Thursday). Data were collected from cats' clinical records.

RESULTS

Complete response was achieved in 72% (n = 36) of the cats, partial response in 24% (n = 13) and 2% (n = 1) did not respond. Median progression-free survival and overall survival times were 316 and 835 days, respectively.

CONCLUSIONS AND RELEVANCE

Results indicated that sex (P = 0.045), extension of the tumour from the nasal planum to the upper lip (P = 0.015), tumour size (P = 0.015; P = 0.001), the existence of a previous treatment (P = 0.043) and the tumour response to high-dose rate brachytherapy (P = 0.038; P <0.001) are prognostic factors for cats with squamous cell carcinoma of the nasal planum following high-dose rate brachytherapy.

Mould-based surface high-dose-rate brachytherapy for eyelid carcinoma

Purpose

To evaluate toxicity and clinical outcomes in patients with eyelid tumour treated with contact high-dose-rate brachytherapy (HDR-BT).

Material and methods

Between April 2010 and August 2017, 10 consecutive patients with tumour of the eyelid underwent contact HDR-BT and custom-made surface mould. Every applicator was manually built using conventional thermoplastic material and standard plastic catheters. The median dose prescribed was 42 Gy (range, 30-48) with a median dose per fraction of 3.5 Gy (range, 2-4.5). The dose was delivered in a median of 12 fractions (range, 10-17) over a median of 16 days. In all cases, an ocular shield was placed to reduce the dose to the eye. Acute and late toxicity was evaluated according to RTOG toxicity criteria.

Results

We analyzed data of 9 of 10 patients (one patient was excluded because he did not give consent for investigation). The median age was 68 years (range, 31-88). According to the TNM-UICC staging system, 4, 1 and 4 patients were stage IA, IB and IC, respectively. Basal cell and sebaceous gland carcinomas were reported in 5 and 2 patients, respectively; other histological types were non-Hodgkin lymphoma and plasmacytoma. After a median follow-up of 51 months (range, 16-90), there was no evidence of local or distant recurrence. The treatment was very well tolerated. Most commonly acute reactions consisted of low grade (G1-G2) conjunctivitis and skin erythema. Only one patient required a temporary interruption of the treatment due to acute G2 conjunctivitis and G3 lid erythema. Only one G2 late toxicity was reported (corneal ulceration), without resulting in functional impairment or blindness.

Conclusions

Our results suggest that contact HDR-BT with a customized applicator is safe, effective and offers very good local control and can be considered for the treatment of eyelid tumours.

Current Role of Radiotherapy in Non-melanoma Skin Cancer

Non-melanoma skin cancer (NMSC) represents the most frequently diagnosed malignancy worldwide, most being cutaneous basal cell and squamous cell carcinoma. The global incidence of NMSC continues to increase as the global population ages. Numerous treatment options are available for NMSC patients, with radiotherapy an efficacious and tissue-preserving non-surgical option. External beam radiotherapy and brachytherapy are modalities with specific indications and advantages in treating NMSC. Where excision is not an option (medically/technically inoperable) or considered less ideal (e.g. cosmetic or functional outcome), radiotherapy offers an excellent alternative. Inoperable elderly and/or co-morbid patients of poor performance status can benefit from short-course hypofractionated radiotherapy, with very acceptable toxicity. Adjuvant radiotherapy in patients with unfavourable pathology can decrease the risk of local and regional recurrence and associated morbidity and mortality. Radiotherapy has advantages and disadvantages and it is important for clinicians to understand these. Managing patients with NMSC is carried out by clinicians from multiple disciplines but it is imperative that they are all aware of the role of radiotherapy in their patients in various clinical settings. Here we aim to discuss the role and indications for recommending radiotherapy in patients with NMSC.

Development and dosimetric assessment of a patient-specific elastic skin applicator for high-dose-rate brachytherapy

PURPOSE

The purpose of this study was to develop a patient-specific elastic skin applicator and to evaluate its dosimetric characteristics for high-dose-rate (HDR) brachytherapy.

METHODS AND MATERIALS

We simulated the treatment of a nonmelanoma skin cancer on the nose. An elastic skin applicator was manufactured by pouring the Dragon Skin (Smooth-On Inc., Easton, PA) with a shore hardness of 10A into an applicator mold. The rigid skin applicator was printed using high-impact polystyrene with a shore hardness of 73D. HDR plans were generated using a Freiburg Flap (FF) applicator and patient-specific rigid and elastic applicators. For dosimetric assessment, dose-volumetric parameters for target volume and normal organs were evaluated. Global gamma evaluations were performed, comparing film measurements and treatment planning system calculations with various gamma criteria. The 10% low-dose threshold was applied.

RESULTS

The V_120% values of the target volume were 56.9%, 70.3%, and 70.2% for HDR plans using FF, rigid, and elastic applicators, respectively. The maximum doses of the right eyeball were 21.7 Gy, 20.5 Gy, and 20.5 Gy for the HDR plans using FF, rigid, and elastic applicators, respectively. The average gamma passing rates were 82.5% ± 1.5%, 91.6% ± 0.8%, and 94.8% ± 0.2% for FF, rigid, and elastic applicators, respectively, with 3%/3 mm criterion.

CONCLUSIONS

Patient-specific elastic skin applicator showed better adhesion to irregular or curved body surfaces, resulting in better agreement between planned and delivered dose distributions. The applicator suggested in this study can be effectively implemented clinically.

[Brachytherapy for head and neck cancers]

The main indications of the brachytherapy of head and neck cancers are the limited tumours of the lip, the nose, the oral cavity and the oropharynx. Nasopharynx tumours are nowadays treated by intensity-modulated radiotherapy. This technique can be exclusive, associated with external radiotherapy or postoperative. It can also be a salvage treatment for the second primaries in previously irradiated areas. If the low dose rate brachytherapy rules remain the reference, the pulse dose rate technique allows the prescription of the dose rate and the optimisation of the dose distribution. Results of high dose rate brachytherapy are now published. This paper reports the recommendations of the Gec-ESTRO, published in 2017, and takes into account the data of the historical low dose rate series, and is upgraded with the pulsed-dose rate and high dose rate series.

GEC-ESTRO ACROP recommendations in skin brachytherapy

PURPOSE

The aim of this publication is to compile available literature data and expert experience regarding skin brachytherapy (BT) in order to produce general recommendations on behalf of the GEC-ESTRO Group.

METHODS

We have done an exhaustive review of published articles to look for general recommendations.

RESULTS

Randomized controlled trials, systemic reviews and meta-analysis are lacking in literature and there is wide variety of prescription techniques successfully used across the radiotherapy centers. BT can be delivered as superficial application (also called contact BT or plesiotherapy) or as interstitial for tumours thicker than 5 mm within any surface, including very irregular. In selected cases, particularly in tumours located within curved surfaces, BT can be advantageous modality from dosimetric and planning point of view when compared to external beam radiotherapy. The general rule in skin BT is that the smaller the target volume, the highest dose per fraction and the shortest overall length of treatment can be used.

CONCLUSION

Skin cancer incidence is rising worldwide. BT offers an effective non-invasive or minimally invasive and relative short treatment that particularly appeals to elder and frail population.

Custom mold applicator high-dose-rate brachytherapy for nonmelanoma skin cancer-An analysis of 273 lesions

PURPOSE

Nonmelanoma skin cancer is the most commonly diagnosed malignancy in the United States. A modern version of surface brachytherapy, "topographic applicator brachytherapy" (TAB), can be used to treat early-stage nonmelanoma skin cancer (ES-NMSC). The purpose of this study was to evaluate the acute toxicity, chronic toxicity, and recurrence rates of patients with ES-NMSC treated with TAB.

METHODS AND MATERIALS

From 2010 to 2013, 172 patients with 273 ES-NMSC tumors were consecutively treated with TAB. A custom applicator was created using a thermoplastic mold with Harrison Anderson Mick applicators. Dose fractionation schemes included 40 Gy in eight fractions delivered twice per week or 48 Gy in 16 fractions delivered four times per week.

RESULTS

Of the 273 tumors treated, 23.8% were located on the nose, 54.2% were basal cell carcinoma, 76.2% were Stage I, 89.3% were treated definitively, 98.9% completed treatment, and 75.5% received 40 Gy in eight fractions. Median followup was 25.0 months (0.5-71.0 months). Maximum acute toxicity was G0, 0.4%; G1, 33.3%; G2, 48.7%; G3, 12.1%; and G4, 5.1%. Local recurrence was 4.8% at 25 months, with median time to recurrence being 9 months. There was no regional or distant metastasis documented during the followup. Chronic toxicities included erythema (4.4%), chronic ulceration (4.0%), telangiectasia (2.6%), and pigmentation changes (2.2%).

CONCLUSIONS

TAB was able to provide excellent local control (95.2%) with low rates of Grades 3 and 4 toxicities for treatment of ES-NMSC. TAB is a reasonable alternative to surgical resection when there is concern of poor cosmesis/wound healing.

Age Is Not a Limiting Factor in Interventional Radiotherapy (Brachytherapy) for Patients with Localized Cancer

This review examines the role of interventional radiotherapy (IRT otherwise known as brachytherapy) in cancer treatment for elderly patients. Despite their advanced age and associated comorbidities, elderly patients should receive definitive cancer therapies, including surgery and radiotherapy (RT). In fact, RT becomes first-line option for patients who are not eligible for surgery (due to comorbidities, anticoagulant drugs, and risk of disfigurement) or those who refuse it. It emerged from this review of the literature as effective, simple, safe, and comfortable and was associated with good local control, low toxicity rates, and excellent cosmesis and provided a cost benefit. IRT may be used as sole treatment for small cancers or as a useful adjunct to surgery or external beam radiotherapy (EBRT) in more advanced (or lymph node positive) cases, especially when the aim is local control with adequate preservation of normal tissue function. As palliative treatment, IRT preserves quality of life and/or improves survival. It is to be hoped that this review will serve as a helpful guide for members of multidisciplinary teams that are involved in treating elderly patients with cancer.

Dosimetric comparison of intensity-modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) in total scalp irradiation: a single institutional experience

PURPOSE

Total scalp irradiation (TSI) is a rare but challenging indication. We previously reported that non-coplanar intensity-modulated radiotherapy (IMRT) was superior to coplanar IMRT in organ-at-risk (OAR) protection and target dose distribution. This consecutive treatment planning study compared IMRT with volumetric-modulated arc therapy (VMAT).

MATERIALS AND METHODS

A retrospective treatment plan databank search was performed and 5 patient cases were randomly selected. Cranial imaging was restored from the initial planning computed tomography (CT) and target volumes and OAR were redelineated. For each patients, three treatment plans were calculated (coplanar/non-coplanar IMRT, VMAT; prescribed dose 50 Gy, single dose 2 Gy). Conformity, homogeneity and dose volume histograms were used for plan.

RESULTS

VMAT featured the lowest monitor units and the sharpest dose gradient (1.6 Gy/mm). Planning target volume (PTV) coverage and homogeneity was better in VMAT (coverage, 0.95; homogeneity index [HI], 0.118) compared to IMRT (coverage, 0.94; HI, 0.119) but coplanar IMRT produced the most conformal plans (conformity index [CI], 0.43). Minimum PTV dose range was 66.8% -88.4% in coplanar, 77.5%-88.2% in non-coplanar IMRT and 82.8%-90.3% in VMAT. Mean dose to the brain, brain stem, optic system (maximum dose) and lenses were 18.6, 13.2, 9.1, and 5.2 Gy for VMAT, 21.9, 13.4, 14.5, and 6.3 Gy for non-coplanar and 22.8, 16.5, 11.5, and 5.9 Gy for coplanar IMRT. Maximum optic chiasm dose was 7.7, 8.4, and 11.1 Gy (non-coplanar IMRT, VMAT, and coplanar IMRT).

CONCLUSION

Target coverage, homogeneity and OAR protection, was slightly superior in VMAT plans which also produced the sharpest dose gradient towards healthy tissue.