Superficial x-ray in the treatment of basal and squamous cell carcinomas: A viable option in select patients

Guidelines for the diagnosis and treatment of basal cell carcinoma: a GRADE approach for evidence evaluation and recommendations by the Italian Association of Medical Oncology

Basal cell carcinoma (BCC) is the most common form of cancer, with a high impact on the public health burden and social costs. Despite the overall prognosis for patients with BCC being excellent, if lesions are allowed to progress, or in a small subset of cases harboring an intrinsically aggressive biological behavior, it can result in local spread and significant morbidity, and conventional treatments (surgery and radiotherapy) may be challenging. When a BCC is not amenable to either surgery or radiotherapy with a reasonable curative intent, or when metastatic spread occurs, systemic treatments with Hedgehog inhibitors are available. These guidelines were developed, applying the GRADE approach, on behalf of the Italian Association of Medical Oncologists (AIOM) to assist clinicians in treating patients with BCC. They contain recommendations with regard to the diagnosis, treatment and follow-up, from primitive tumors to those locally advanced or metastatic, addressing the aspects of BCC management considered as priorities by a panel of experts selected by AIOM and other national scientific societies. The use of these guidelines in everyday clinical practice should improve patient care.

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.

The Role of Radiation Therapy in the Treatment of Non-Melanoma Skin Cancer

Non-melanoma skin cancer (NMSC) is the most common malignancy in the United States. While surgery is considered as the main treatment modality for both cutaneous basal cell carcinoma (cBCC) and cutaneous squamous cell carcinoma (cSCC), radiotherapy plays an important role in the treatment of NMSC, both in the adjuvant setting for cases considered high-risk for recurrence, and in the definitive setting, when surgery is not feasible or desired by the patient. The last years have seen the emergence of immunotherapy treatment for cases of advanced cSCC in the palliative, and possibly neoadjuvant settings, making the treatment paradigm more complex. In this review, we attempt to describe the different radiation modalities available for the treatment of NMSC, the indications for adjuvant post-operative treatment with radiotherapy for cSCC, the role of radiotherapy in elective neck treatment, and the efficacy, safety, and toxicity profile of this treatment in these different settings. Furthermore, we aim to describe the efficacy of radiotherapy combined with immunotherapy as a promising horizon for treating advanced cSCC. We also aim to describe the ongoing clinical studies that attempt to examine future directions for the role of radiation treatment in NMSC.

The Involvement of Photobiology in Contemporary Dentistry-A Narrative Review

Light is an emerging treatment approach that is being used to treat many diseases and conditions such as pain, inflammation, and wound healing. The light used in dental therapy generally lies in visible and invisible spectral regions. Despite many positive results in the treatment of different conditions, this therapy still faces some skepticism, which has prevented its widespread adoption in clinics. The main reason for this skepticism is the lack of comprehensive information about the molecular, cellular, and tissular mechanisms of action, which underpin the positive effects of phototherapy. However, there is currently promising evidence in support of the use of light therapy across a spectrum of oral hard and soft tissues, as well as in a variety of important dental subspecialties, such as endodontics, periodontics, orthodontics, and maxillofacial surgery. The merging of diagnostic and therapeutic light procedures is also seen as a promising area for future expansion. In the next decade, several light technologies are foreseen as becoming integral parts of modern dentistry practice.

Association of Patient Risk Factors, Tumor Characteristics, and Treatment Modality With Poor Outcomes in Primary Cutaneous Squamous Cell Carcinoma: A Systematic Review and Meta-analysis

Importance

Primary cutaneous squamous cell carcinoma is usually curable; however, a subset of patients develops poor outcomes, including local recurrence, nodal metastasis, distant metastasis, and disease-specific death.

Objectives

To evaluate all evidence-based reports of patient risk factors and tumor characteristics associated with poor outcomes in primary cutaneous squamous cell carcinoma and to identify treatment modalities that minimize poor outcomes.

Data Sources

PubMed, Embase, and SCOPUS databases were searched for studies of the topic in humans, published in the English language, from database inception through February 8, 2022.

Study Selection

Two authors independently screened the identified articles and included those that were original research with a sample size of 10 patients or more and that assessed risk factors and/or treatment modalities associated with poor outcomes among patients with primary cutaneous squamous cell carcinoma.

Data Extraction and Synthesis

Data extraction was performed by a single author, per international guidelines. The search terms, study objectives, and protocol methods were defined before study initiation. A total of 310 studies were included for full-text assessment. Owing to heterogeneity of the included studies, a random-effects model was used. Data analyses were performed from May 25 to September 15, 2022.

Main Outcomes and Measures

For studies of risk factors, risk ratios and incidence proportions; and for treatment studies, incidence proportions.

Results

In all, 129 studies and a total of 137 449 patients with primary cutaneous squamous cell carcinoma and 126 553 tumors were included in the meta-analysis. Several patient risk factors and tumor characteristics were associated with local recurrence, nodal metastasis, distant metastasis, disease-specific death, and all-cause death were identified. Among all factors reported by more than 1 study, the highest risks for local recurrence and disease-specific death were associated with tumor invasion beyond subcutaneous fat (risk ratio, 9.1 [95% CI, 2.8-29.2] and 10.4 [95% CI, 3.0- 36.3], respectively), and the highest risk of any metastasis was associated with perineural invasion (risk ratio, 5.0; 95% CI, 2.3-11.1). Patients who received Mohs micrographic surgery had the lowest incidence of nearly all poor outcomes; however, in some results, the 95% CIs overlapped with those of other treatment modalities.

Conclusions and Relevance

This meta-analysis identified the prognostic value of several risk factors and the effectiveness of the available treatment modalities. These findings carry important implications for the prognostication, workup, treatment, and follow-up of patients with primary cutaneous squamous cell carcinoma.

Trial Registration

PROSPERO Identifier: CRD42022311250.

Analysis of image-guided superficial radiation therapy (IGSRT) on the treatment of early-stage non-melanoma skin cancer (NMSC) in the outpatient dermatology setting

BACKGROUND

Interest in image-guidance superficial radiation therapy (IGSRT) for the treatment of early-stage non-melanoma skin cancer (NMSC) has resurfaced given its low complication rates, superior cosmesis and local control and cure rates. In addition, it has been recommended by the American Academy of Dermatology (AAD) for early-stage NMSC in patients who are considered poor surgical candidates.

METHODS

1899 NMSC lesions were treated with energies ranging from 50 to 100 kilovoltage (kV), for a mean of 20.2 fractions, and treatment dose of 5364.4 centigray (cGy). Lesions were treated for a mean of 7.5 weeks and followed for 65.5 weeks. SAS studio was used to conduct Kaplan-Meier analysis to calculate local control rates and account for differences in follow-up intervals. A log-rank test was used to calculate statistical differences between histologies.

RESULTS

Absolute lesion control was achieved in 99.7% of the patients after an average of 7.5 weeks of treatment, with a stable control rate of 99.6% when the follow-up duration was over 12 months. 95% of lesions with toxicity scoring received a Radiation Treatment Oncology Group Toxicity (RTOG) score of 1 or 2.

CONCLUSION

IGSRT has a high safety profile, can achieve superior cosmesis and should be considered first-line for treating early-stage NMSC tumors as cure rates have been shown to be effective in all NMSC on early follow-up.

Radiotherapy for cutaneous squamous cell carcinoma: current standards and outlooks

Cutaneous squamous cell carcinoma accounts for 20 % of all malignant non-melanoma skin tumors, which is one of the most common cancers worldwide. Antitumor treatment is usually very effective: cure rate reaches 90 %, while local recurrence rate is 25 %. The main treatment option for primary skin cancers is surgery. The most significant risk factors for locoregional recurrence include tumor location (head and neck), size (>2 cm), depth of invasion (>4 mm), tumor differentiation grade, perineural invasion, immune system disorders (immunosuppression), severe concomitant diseases, and previous treatment.

In patients with advanced cutaneous squamous cell carcinoma, 1-year, 2-year, and 3-year survival rates are 50–80, 30–35 and 15–16 %, respectively. Radiotherapy is a radical treatment option that increases the 5-year survival rate to 90 % and ensures good cosmetic results in 80 % of cases. There are 3 main variants of radiotherapy for cutaneous squamous cell carcinoma: sole radiotherapy according to a radical program, adjuvant radiotherapy in combination with surgery, and palliative radiotherapy. most frequently, radiotherapy is used as part of adjuvant postoperative treatment and is not initially considered as a sole conservative treatment for cutaneous squamous cell carcinoma patients below 45 years of age with resectable tumors, especially high-risk tumors. palliative radiotherapy is an affordable and effective method for combating painful symptoms; moreover, it often provides long-term local control. 

Advances in Management and Therapeutics of Cutaneous Basal Cell Carcinoma

Simple Summary

Basal cell carcinoma (BCC) is the most common malignancy in humans with a range of treatment options available. Tumor and patient characteristics aid in risk-stratification, which influences treatment considerations. Here, we review the advancements in surgical, topical, field, immunotherapeutic, molecular-targeted, and experimental treatment modalities that can be employed in the correct clinical setting for the treatment of BCC.

Abstract

Basal cell carcinoma (BCC), the most common cancer in humans, is a malignant neoplasm of cells derived from the basal layer of the epidermis. Tumor characteristics such as histologic subtype, primary versus recurrent tumor, anatomic location, size, and patient attributes determine the risk level and acceptable treatment options. Surgical options offer histologic confirmation of tumor clearance. Standard excision provides post-treatment histologic assessment, while Mohs micrographic surgery (MMS) provides complete margin assessment intraoperatively. Additional treatment options may be employed in the correct clinical context. Small and low-risk BCCs, broad field cancerization, locally-advanced disease, metastatic disease, cosmetic concerns, or morbidity with surgical approaches raise consideration of other treatment modalities. We review herein a range of treatment approaches and advances in treatments for BCC, including standard excision, MMS, electrodesiccation and curettage, ablative laser treatment, radiation therapy, targeted molecular therapies, topical therapies, field therapies, immunotherapy, and experimental therapies.

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.

A SHort course Accelerated RadiatiON therapy (SHARON) dose-escalation trial in older adults head and neck non-melanoma skin cancer

OBJECTIVES

To assess feasibility and safety of a SHort-course Accelerated RadiatiON therapy (SHARON) regimen, in the treatment of non-melanoma skin cancers (NMSC) in older patients.

METHODS

Old patients (age ≥ 80 years) with histological confirmed non-melanoma skin cancers were enrolled. The primary endpoint was to determine the maximum tolerated dose (MTD). Radiotherapy regimen was based on the delivery of four radiotherapy fractions (5 Gy per fraction) with a twice daily fractionation in two consecutive days. Three different level of dose were administered: 20 Gy (one cycle), 40 Gy (two cycles) and 60 Gy (three cycles).

RESULTS

Thirty patients (median age: 91 years; range: 80-96) were included in this analysis. Among fourteen patients who completed the one cycle, only one (7%) experimented acute G4 skin toxicity. Twelve patients reported an improvement or resolution of baseline symptoms (overall palliative response rate: 85.8%). Nine and seven patients underwent to two and three RT cycles, respectively: of these, no G3 toxicities were recorded. The overall response rate was 100% when three cycles were delivered. The overall six-month symptom-free survival was 78.7% and 77.8% in patients treated with one course and more courses, respectively.

CONCLUSIONS

Short-course accelerated radiotherapy in older patients with non-melanoma skin cancers is well tolerated. High doses seem to be more effective in terms of response rate.

ADVANCES IN KNOWLEDGE

This approach could represent an option for older adults with NMSC, being both palliative (one course) or potentially curative (more courses) in the aim, accordingly to the patient's condition.

Basal Cell Carcinoma: an updated review of pathogenesis and treatment options

Basal cell carcinoma (BCC) remains the most common malignancy worldwide. BCC pathogenesis is a result of the interplay between one's environment, genetics, and phenotypic factors. BCC has a low mortality but given its increasing incidence and potential to cause local destruction thus resulting in significant morbidity, it is vital for dermatologists to remain up to date with recent updates in this malignancy's pathogenesis and treatment. This article provides a comprehensive review of the pathogenesis of BCC as well as the current treatments available and clinical trials underway. We also touch upon the updated National Comprehensive Cancer Network Clinical Practice Guidelines in Oncology in respect to BCC's recommended treatment modalities.

Current Perspectives in the Treatment of Locally Advanced Basal Cell Carcinoma

Basal cell carcinoma (BCC) is the most common cancer in Caucasians, and its incidence continues to rise. Generally, BCCs have good outcomes when diagnosed and treated early. However, 1-10% of patients will develop advanced disease due to either delays in accessing treatment or aggressive tumors that may be refractory to treatment. Locally advanced basal cell carcinomas (laBCCs) are large, aggressive, or recurrent tumors that have the potential to invade surrounding tissues including bone, cartilage, nerve, and muscle. Treatment requires a multi-disciplinary approach where different modalities including surgery, radiation therapy, Hedgehog Pathway Inhibitors, and immunotherapy can be considered.

A New Approach for a Safe and Reproducible Seeds Positioning for Diffusing Alpha-Emitters Radiation Therapy of Squamous Cell Skin Cancer: A Feasibility Study

Simple Summary

The Diffusing Alpha-emitters Radiation Therapy (DaRT) is a novel brachytherapy technique employing 224-radium enriched seeds releasing short-lived alpha-emitting atoms into the tumour. DaRT overcomes the main obstacle in employing alpha radiation for cancer treatments in liquid and solid media caused by their short range. The aim of the study is to improve the DaRT technique with an external radio-opaque template that can help clinicians predict the correct number of sources to achieve tumour coverage. Furthermore, the template is used to aid clinicians in visualizing lesions and their eventual subcutaneous extension. Finally, it is also utilized on treatment day to ensure that the sources are properly inserted into the tumour.

Abstract

The purpose of this study is to discuss how to use an external radio-opaque template in the Diffusing Alpha-emitters Radiation Therapy (DaRT) technique’s pre-planning and treatment stages. This device would help to determine the proper number of sources for tumour coverage, accounting for subcutaneous invasion and augmenting DaRT safety. The procedure will be carried out in a first phase on a phantom and then applied to a clinical case. A typical DaRT procedure workflow comprises steps like tumour measurements and delineation, source number assessment, and therapy administration. As a first step, an adhesive fiberglass mesh (spaced by 2 mm) tape was applied on the skin of the patient and employed as frame of reference. A physician contoured the lesion and marked the entrance points for the needles with a radio opaque ink marker. According to the radio opaque marks and metabolic uptake the clinical target volume was defined, and with a commercial brachytherapy treatment planning system (TPS) it was possible to simulate and adjust the spatial seeds distribution. After the implant procedure a CT was again performed to check the agreement between simulations and seeds positions. With the procedure described above it was possible to simulate a DaRT procedure on a phantom in order to train physicians and subsequently apply the novel approach on patients, outlining the major issues involved in the technique. The present work innovates and supports DaRT technique for the treatment of cutaneous cancers, improving its efficacy and safety.

Radiation therapy of cutaneous cancers

We present the update of the recommendations of the French society of oncological radiotherapy on radiotherapy of cutaneous cancers. The indications of radiotherapy for skin cancers are not clearly defined because of the lack of randomized trials or prospective studies. For basal cell carcinomas, radiotherapy frequently offers a good local control, but a randomized trial showed that surgery is more efficient and less toxic. Indications of radiotherapy are contra-indications of surgery for patients older than 60, non-sclerodermiform histology and located in non-sensitive areas. Adjuvant radiotherapy could be proposed to squamous cell carcinomas, in case of poor prognostic factors. Dose of 60 to 70Gy are usually required, and must be modulated to the size of the lesions. Adjuvant radiotherapy seems beneficial for desmoplastic melanomas but not for the other histological types. Prophylactic nodal irradiation (45 to 50Gy), for locally advanced tumors (massive nodal involvement), decreases the locoregional failure rate but do not increase survival. Adjuvant radio- therapy (50 to 56Gy) for Merkel cell carcinomas increases also the local control rate, as demonstrated by meta-analysis and a large epidemiological study. Nodal areas must be included, if there is no surgical exploration (sentinel lymph node dissection). Kaposi sarcomas are radiosensitive and could be treated with relatively low doses (24 to 30Gy). Also, cutaneous lymphomas are good indications for radiotherapy: B lymphomas are electively treated with limited fields. The role of total skin electron therapy for T-lymphomas is still discussed; but palliative radiotherapy is very efficient in case of cutaneous nodules.

NCCN Guidelines® Insights: Squamous Cell Skin Cancer, Version 1.2022

The NCCN Guidelines for Squamous Cell Skin Cancer provide recommendations for diagnostic workup, clinical stage, and treatment options for patients with cutaneous squamous cell carcinoma. The NCCN panel meets annually to discuss updates to the guidelines based on comments from panel members and the Institutional Review, as well as submissions from within NCCN and external organizations. These NCCN Guidelines Insights focus on the introduction of a new surgical recommendation terminology (peripheral and deep en face margin assessment), as well as recent updates on topical prophylaxis, immunotherapy for regional and metastatic disease, and radiation therapy.

Non-Surgical Treatments for Keratinocyte Carcinomas

Skin cancer is the most common malignancy worldwide, comprising approximately 30% of all human tumors. In recent decades, the incidence of keratinocyte carcinomas, which include basal cell carcinoma and cutaneous squamous cell carcinoma, has been steadily increasing globally (Rogers et al. in JAMA Dermatol 151(10):1081-1086. https://doi.org/10.1001/jamadermatol.2015.1187 , 2015; Nehal and Bichakjian in N Engl J Med 379(4):363-374. https://doi.org/10.1056/nejmra1708701 , 2018). Most tumors are cured with surgical excision; however, some tumors are best treated with non-surgical approaches. Superficial tumors can often be cured with non-surgical methods whereas more advanced stage tumors may not be amenable to surgery. Additionally, surgical treatment may not be available for all populations depending on geographic location and accessibility to care. This article reviews commonly utilized nonsurgical options such as cryotherapy, photodynamic therapy, topical treatments, and radiation as well as systemic treatments including immunotherapies and chemotherapies.

Treatment of advanced cutaneous squamous cell carcinoma: a Mohs surgery and dermatologic oncology perspective

Locally advanced or metastatic cutaneous squamous cell carcinoma no longer amenable to surgical resection or primary radiation therapy requires an alternative approach to treatment. Until 2018, management consisted of limited systemic chemotherapies, which carried marginal clinical benefit. The introduction of immunotherapy with anti-PD-1 antibodies resulted in alternative treatment options for advanced cutaneous squamous cell carcinoma with substantial antitumor activity, durable response and acceptable safety profile. The field of immunotherapeutics continues to expand with adjuvant, neoadjuvant and intralesional studies currently in progress. Herein, the authors discuss their approach for the treatment of advanced cutaneous squamous cell carcinoma from the perspective of a Mohs surgeon and a dermatologic oncologist.

A Systematic Review of Primary, Adjuvant, and Salvage Radiation Therapy for Cutaneous Squamous Cell Carcinoma

BACKGROUND

The gold standard of treatment for cutaneous squamous cell carcinoma (cSCC) is surgery radiation therapy (RT) is used selectively as definitive treatment for low-risk tumors or as adjuvant/salvage treatment for high-risk tumors. There is a lack of standardized studies evaluating the efficacy of RT in either clinical scenario.

OBJECTIVE

To determine the efficacy of primary and adjuvant/salvage RT for the treatment of cSCC.

MATERIALS AND METHODS

A systematic review of PubMed, Embase, Cochrane, and Web of Science was performed for studies that reported outcomes of cSCC treated with RT to the primary site alone. Outcomes included local control (LC), local recurrence (LR), nodal metastases (NM), distant metastases (DM), disease-specific death (DSD), and recurrence-free survival (RFS).

RESULTS

Forty-six studies with 4,141 tumors were included. Pooled LC and LR rates were 87.3% and 8.6%, respectively. The rates of NM, DM, DSD, and RFS were 4.8%, 3.5%, 5.3%, and 73.5%, respectively. Local recurrence was significantly higher for T3 and T4 tumors, with rates above 25.9%.

CONCLUSION

LR after RT to the primary site increased with increasing tumor stage, highlighting the importance of clear surgical margins for high-risk tumors. Prospective randomized studies characterizing outcomes by tumor stage for RT compared with surgery are needed to inform guidelines.

Adjuvant radiation and cetuximab improves local control in head and neck cutaneous squamous cell carcinoma: A phase II study

BACKGROUND

Cutaneous squamous cell carcinoma of the head/neck (CSCCHN) is common due to chronic sun exposure. As CSCCHN highly expresses EGFR, we prospectively studied postoperative concurrent cetuximab with radiotherapy for locally advanced CSCCHN (LA-CSCCHN).

MATERIALS AND METHODS

Single-institutional phase II trial of LA-CSCCHN (NCT XXXX). Adjuvant radiation was given with concurrent cetuximab. Primary endpoint of 2-year LRC and secondary objectives of 2-year disease-free survival (DFS) and 2-year OS were assessed by Kaplan-Meier analysis.

RESULTS

Twenty-four patients ages 47-88 (median 71 years) were treated from 2014 to 2017. Fourteen patients had T3/4 disease, 5 had N1 disease, and 7 were N2/3. At median follow-up of 42 months, median OS and DFS was not reached and 64 months. Two-year OS was 75%, 2-year DFS was 70.8%. LRC was 91.1% at 2 years. All grade 3 adverse events were related to skin toxicity (12.5% radiation-related dermatitis, 16.7% cetuximab-related rash).

CONCLUSIONS

LRC compares favorably to historical data examining postoperative radiation alone but requires further investigation.

Cutaneous Malignancies of the Head and Neck

Cutaneous malignancies (CMs), or skin cancers, are the most common cancer worldwide, with a quarter million cases diagnosed annually in the United States alone. The best described risk factor for CM is ultraviolet radiation from sunlight, and therefore most of these cancers develop in sun-exposed skin, including the head and neck. Beginning with melanoma, immunotherapy has increasingly been used over the past decade for treatment of unresectable CM, and immune checkpoint inhibitors are now Food and Drug Administration-approved for first-line treatment of unresectable melanoma, Merkel cell carcinoma, and cutaneous squamous cell carcinoma, and second-line for basal cell carcinoma.

The value of primary and adjuvant radiotherapy for cutaneous squamous cell carcinomas of the head-and-neck region in the elderly

Purpose

To examine treatment patterns, oncological outcomes and toxicity rates in elderly patients receiving radiotherapy for cutaneous squamous cell carcinoma (cSCC) of the head-and-neck region.

Material and methods

In this retrospective single-center analysis, locoregional control (LRC), progression-free survival (PFS) and overall survival (OS) of elderly patients > 65 years with cSCC of the head-and-neck region undergoing radiotherapy between 2010 and 2019 were calculated. The prognostic value of clinicopathological parameters on radiotherapy outcomes was analyzed using the Cox proportional hazards model. In addition, both acute and chronic toxicities were retrospectively quantified according to CTCAE version 5.0.

Results

A total of 69 elderly patients with cSCC of the head-and-neck region with a median age of 85 years were included in this analysis, of whom 21.7% (15 patients) presented with nodal disease. The majority of patients exhibited a good performance status, indicated by a median Karnofsky performance status (KPS) and Charlson Comorbidity Index (CCI) of 80% and 6 points, respectively. Radiotherapy was administered as primary (48%), adjuvant (32%) or palliative therapy (20%). 55 patients (79.7%) completed treatment and received the scheduled radiotherapy dose. Median EQD2 radiation doses were 58.4 Gy, 60 Gy and 51.3 Gy in the definitive, adjuvant and palliative situation, respectively. 2-year LRC, PFS and OS ranged at 54.2%, 33.5 and 40.7%, respectively. Survival differed significantly between age groups with a median OS of 20 vs. 12 months (p < 0.05) for patients aged 65–80 or above 80 years. In the multivariate analysis, positive lymph node status remained the only significant prognostic factor deteriorating OS (HR 3.73, CI 1.54–9.03, p < 0.01). Interestingly, neither KPS nor CCI impaired survival in this elderly patient cohort. Only 3 patients (4.3%) experienced acute CTCAE grade 3 toxicities, and no chronic CTCAE grade 2–5 toxicities were observed in our cohort.

Conclusion

Radiotherapy was feasible and well-tolerated in this distinct population, showing the general feasibility of radiotherapy for cSCC of the head-and-neck region also in the older and oldest olds. The very mild toxicities may allow for moderate dose escalation to improve LRC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13014-021-01832-3.

The role of radiation therapy in the management of cutaneous malignancies. Part II: When is radiation therapy indicated?

Radiation therapy may be performed for a variety of cutaneous malignancies, depending on patient health status, tumor clinical and histologic features, patient preference, and resource availability. Dermatologists should be able to recognize the clinical scenarios in which radiation therapy is appropriate, as this may reduce morbidity, decrease risk of disease recurrence, and improve quality of life. The second article in this 2-part continuing medical education series focuses on the most common indications for radiation therapy in the treatment of basal cell carcinoma, cutaneous squamous cell carcinoma, dermatofibrosarcoma protuberans, Merkel cell carcinoma, Kaposi sarcoma, angiosarcoma, cutaneous lymphoma, melanoma, undifferentiated pleomorphic sarcoma, and sebaceous carcinoma.

The role of radiation therapy in the management of cutaneous malignancies. Part I: Diagnostic modalities and applications

Radiation therapy offers distinct advantages over other currently available treatments for cutaneous malignancies in certain circumstances. Dermatologists and dermatologic surgeons should be familiar with the available radiation therapy techniques as well as their value and potential limitations in a variety of clinical scenarios. The first article in this 2-part continuing medical education series highlights the mechanisms, modalities, and applications of the most commonly used radiotherapy treatments as they relate to cutaneous oncology. We review the current indications for the use of radiation in the treatment of various cutaneous malignancies, the techniques commonly employed in modern radiotherapy, and the associated complications.

Tumor Control Probability Modeling for Radiation Therapy of Keratinocyte Carcinoma

Summary

Skin cancer patients may be treated definitively using radiation therapy (RT) with electrons, kilovoltage, or megavoltage photons depending on tumor stage and invasiveness. This study modeled tumor control probability (TCP) based on the pooled clinical outcome data of RT for primary basal and cutaneous squamous cell carcinomas (BCC and cSCC, respectively). Four TCP models were developed and found to be potentially useful in developing optimal treatment schemes based on recommended ASTRO 2020 Skin Consensus Guidelines for primary, keratinocyte carcinomas (i.e. BCC and cSCC).

Background

Radiotherapy (RT) with electrons or photon beams is an excellent primary treatment option for keratinocyte carcinoma (KC), particularly for non-surgical candidates. Our objective is to model tumor control probability (TCP) based on the pooled clinical data of primary basal and cutaneous squamous cell carcinomas (BCC and cSCC, respectively) in order to optimize treatment schemes.

Methods

Published reports citing crude estimates of tumor control for primary KCs of the head by tumor size (diameter: ≤2 cm and >2 cm) were considered in our study. A TCP model based on a sigmoidal function of biological effective dose (BED) was proposed. Three-parameter TCP models were generated for BCCs ≤2 cm, BCCs >2cm, cSCCs ≤2 cm, and cSCCs >2 cm. Equivalent fractionation schemes were estimated based on the TCP model and appropriate parameters.

Results

TCP model parameters for both BCC and cSCC for tumor sizes ≤2 cm and >2cm were obtained. For BCC, the model parameters were found to be TD₅₀ = 56.62 ± 6.18 × 10^-3 Gy, k = 0.14 ± 2.31 × 10⁻² Gy⁻¹ and L = 0.97 ± 4.99 × 10⁻³ and TD₅₀ = 55.78 ± 0.19 Gy, k = 1.53 ± 0.20 Gy⁻¹ and L = 0.94 ± 3.72 × 10⁻³ for tumor sizes of ≤2 cm and >2 cm, respectively. For SCC the model parameters were found to be TD₅₀ = 56.81 ± 19.40 × 10⁴ Gy, k = 0.13 ± 7.92 × 10⁴ Gy⁻¹ and L = 0.96 ± 1.31 × 10^-2 and TD₅₀ = 58.44 ± 0.30 Gy, k = 2.30 ± 0.43 Gy⁻¹ and L = 0.91± 1.22 × 10⁻² for tumors ≤2cm and >2 cm, respectively. The TCP model with the derived parameters predicts that radiation regimens with higher doses, such as increasing the number of fractions and/or dose per fraction, lead to higher TCP, especially for KCs >2 cm in size.

Conclusion

Four TCP models for primary KCs were developed based on pooled clinical data that may be used to further test the recommended kV and MV x-ray and electron RT regimens from the 2020 ASTRO guidelines. Increasing both number of fractions and dose per fraction may have clinically significant effects on tumor control for tumors >2 cm in size for both BCC and cSCC.

Japanese Dermatological Association Guidelines: Outlines of Guidelines for Cutaneous Squamous Cell Carcinoma 2020

In consideration of the development of treatment options for squamous cell carcinoma (SCC), the Japanese Skin Cancer Society issued the first guidelines of SCC in 2007 and revised them in 2015. Here, we report the English version of the 2020 edition of the Japanese SCC guidelines. The first half of this article is an overview of SCC including actinic keratosis and Bowen's disease, and the second half discusses three clinical questions: (i) treatment of actinic keratosis; (ii) determination of the resection margin of the primary lesion; and (iii) treatment of radically incurable cases, as contemporary problems encountered in treating SCC. In these evaluations, all processes were implemented according to the Grading of Recommendations, Assessment, Development, Evaluation system. Also, items of recommendation concerning each clinical question were determined by a multidisciplinary expert panel consisting of dermatologists, plastic/reconstructive surgeons, radiologists, and oncologists through a comprehensive literature search and systematic reviews.

A small case series about safety and effectiveness of a hypofractionated electron beam radiotherapy schedule in five fractions for facial non melanoma skin cancer among frail and elderly patients

Background

The aim of the study was to evaluate local control and toxicities of strongly hypofractionated electron beam radiotherapy (RT) in elderly and fragile patients with facial nonmelanoma skin cancer (NMSC).

Materials and methods

We enrolled patients aged ≥ 65 years with facial NMSC, Karnofsky Performance Status (KPS) ≥ 40 and life expectancy ≥ 6 months, amenable neither to daily RT nor surgery. Radiotherapy consisted of 35 Gy, delivered with 6 MeV electron beam, in 5 fractions of 7 Gy/day twice a week (tw). Prescription isodoses were 100% for cT1-cT2 and 90% for cT3-cT4. Objective response was assessed clinically 4 and 8 weeks after the end of RT and then monitored every 6 months. Side effects were assessed according to the CTCAE scale.

Results

12 patients of median age 89.5 years with a total of 23 NMSC cN0 achieved a median follow-up time of 6 months (range 1-10), with total treatment compliance. 10/12 patients had a 40 ≤ KPS < 70 and 2/12 a 70 ≤ KPS < 90. 5/12 patients had synchronous lesions. 22/23 lesions were classified as T1-T2 and had complete response (CR), 1/23 as T4 with partial response (PR). Within 4 weeks after the end of treatment, G1 toxicity was reported for 12/23 lesions, G2 for 8/23, G3 for 3/23, G4 for 0/23, all disappeared 8 weeks later, with or without topical therapy. After last follow-up (1 June 2020) 1/12 patients died with PR from senile marasmus, 11/12 are alive with CR and widely tolerated toxicities.

Conclusions

Extreme hypofractionation of radiotherapy dose for facial NMSC is effective, safe and suitable for elderly patients.

The Treatment of Non-Melanoma Skin Cancer with Image-Guided Superficial Radiation Therapy: An Analysis of 2917 Invasive and In Situ Keratinocytic Carcinoma Lesions

Introduction

An image-guided form of superficial ionizing radiation therapy (IGSRT) is becoming a commonly used alternative to surgery for non-melanoma skin cancer (NMSC). However, there is little literature evidence evaluating the efficacy and safety of this approach. This study evaluates the efficacy and safety of IGSRT in treating a large number of patients with NMSC.

Methods

The medical records of 1632 stage 0–II patients with 2917 invasive and in situ NMSC lesions treated from years 2017 to 2020 were reviewed. No patients had clinical evidence of regional lymph node or distant disease at presentation.

Results

Treatment, guided by pre-treatment ultrasound imaging to adjust radiation energy and dose, combined with a fractionation treatment schedule of 20 or more treatment fractions, was safe and well tolerated. Of 2917 NMSC lesions treated, local tumor control was achieved in 2897 lesions, representing a 99.3% rate of control.

Conclusion

IGSRT should be considered as a first-line option for treating NMSC tumors in suitable early stage patients. Cure rates observed in this initial period of follow-up are similar, and potentially superior with further follow-up, to traditional superficial radiation therapy (SRT) and surgical options.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40487-021-00138-4.

Beyond Mohs surgery and excisions: A focused review of treatment options for subtypes of basal cell carcinoma

Basal cell carcinoma (BCC) is the most common nonmelanoma skin cancer. It originates from undifferentiated cells in the basal cell layer of the epidermis or from the outer root sheath of the hair follicle. The most important factor in development of BCC is ultraviolet radiation. Surgery is considered the gold standard of treatment for BCC. However, nonsurgical options are available for individuals who are unsuitable for surgery. The purpose of this review is to summarize the efficacy and indications of alternative, nonsurgical treatments that can be used in the management of BCC. An extensive literature review was performed for the nonsurgical options for the treatment of BCC. Resources searched included PubMed and Google Scholars, limited to the years 1995 to 2020. Key words searched included BCC, destructive methods, photodynamic therapy (PDT), radiotherapy, topical medication, laser, hedgehog pathway inhibitors (HPIs). The most relevant results such as systematic reviews, randomized controlled trials, or comparative studies were selected to provide a summary for the most common nonsurgical methods used for treating BCC. Effective nonsurgical treatments for BCC include destructive methods (eg, curettage alone, cryosurgery, or electrodessication), PDT, topical medications, radiotherapy, laser, and HPIs. Nonsurgical therapeutic alternatives are safe and effective for the treatment of BCC. Factors such as tumor location, size, and histopathological subtype should be taken into consideration when selecting optimal treatment. In addition to clinical factors, cosmetic results and patient preference should be considered.

Stimuli-responsive and cellular targeted nanoplatforms for multimodal therapy of skin cancer

Interdisciplinary applications of nanopharmaceutical sciences have tremendous potential for enhancing pharmacokinetics, efficacy and safety of cancer therapy. The limitations of conventional therapeutic platforms used for skin cancer therapy have been largely overcome by the use of nanoplatforms. This review discusses various nanotechnological approaches experimented for the treatment of skin cancer. The review describes various polymeric, lipidic and inorganic nanoplatforms for efficient therapy of skin cancer. The stimuli-responsive nanoplatforms such as pH-responsive as well as temperature-responsive platforms have also been reviewed. Different strategies for potentiating the nanoparticles application for cancer therapy such as surface engineering, conjugation with drugs, stimulus-responsive and multimodal effect have also been discussed and compared with the available conventional treatments. Although, nanopharmaceuticals face challenges such as toxicity, cost and scale-up, efforts put-in to improve these drawbacks with continuous research would deliver exciting and promising results in coming days.

Treatment of keratinocyte carcinoma in elderly patients - a review of the current literature

A large percentage of the patients with keratinocyte carcinoma (KC, formerly known as non‐melanoma skin cancer) is of advanced age and often too frail for standard therapies. However, no specific treatment recommendations are given for this population. This review aimed to give an overview of the current literature on the best practice for the treatment of elderly patients with KC. A literature search was performed in MEDLINE, using ‘keratinocyte carcinoma’, ‘elderly’, ‘treatment’ and various synonyms. Case reports, reviews, comments, non‐English literature and studies with a sample size <15 were excluded. After selection, a total of 47 studies were reviewed. Two types of studies were identified, focusing on (I) the effect of age on treatment outcomes and (II) alternative treatment schedules for elderly patients. Studies on surgery, the gold standard, describe larger lesions and defect size in the elderly population. Recurrence rate, complication rate and disease‐specific survival were not affected by age. Depending on the expected morbidity of a suggested (re‐)excision and patient preferences, a conservative watchful waiting policy can be agreed upon as a shared decision. Other common treatment modalities, such as adjuvant radiotherapy, photodynamic therapy and systemic therapy for basal cell carcinoma (BCC), show comparable results in the elderly and younger population. Alternative treatment schedules for elderly patients include primary hypofractionated radiotherapy, which seems effective and well‐tolerated, although research is limited to case series. Additionally, localized and topical treatments seem safe and effective especially for low‐risk tumours. Data are lacking on the efficacy of systemic therapies of metastatic KC in elderly patients. Efficacy of most treatments (with the exception of photodynamic therapy) is not dependent on age. There is need for more research on the efficacy of adjusted treatment modalities, such as hypofractionated radiotherapy and palliative or curative systemic treatment.

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

PURPOSE

This guideline reviews the evidence for the use of definitive and postoperative radiation therapy (RT) in patients with basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (cSCC).

METHODS

The American Society for Radiation Oncology convened a task force to address 5 key questions focused on indications for RT in the definitive and postoperative setting for BCC and cSCC, as well as dose-fractionation schemes, target volumes, basic aspects of treatment planning, choice of radiation modality, and the role of systemic therapy in combination with radiation. Recommendations were based on a systematic literature review and created using a predefined consensus-building methodology and system for grading evidence quality and recommendation strength.

RESULTS

The guideline recommends definitive RT as primary treatment for patients with BCC and cSCC who are not surgical candidates while conditionally recommending RT with an emphasis on shared decision-making in those situations in which adequate resection can lead to a less than satisfactory cosmetic or functional outcome. In the postoperative setting, a number of indications for RT after an adequate resection are provided while distinguishing the strength of the recommendations between BCC and cSCC. One key question is dedicated to defining indications for regional nodal irradiation. The task force suggests a range of appropriate dose-fractionation schemes for treatment of primary and nodal volumes in definitive and postoperative scenarios. The guideline also recommends against the use of carboplatin concurrently with adjuvant RT and conditionally recommends the use of systemic therapies for unresectable primaries where treatment may need escalation.

CONCLUSIONS

Defining the role of RT in the management of BCC and cSCC has been hindered by a lack of high-quality evidence. This document synthesizes available evidence to define practice guidelines for the most common clinical situations. We encourage practitioners to enroll patients in prospective trials and to approach care in a multidisciplinary fashion whenever possible.

Intrabeam Radiation Inhibits Proliferation, Migration, and Invasiveness and Promotes Apoptosis of MCF-7 Breast Cancer Cells

Intraoperative radiotherapy differs from the more commonly used external beam radiation with respect to fractionation, radiation energy, dose rate, and target volume, which may influence the irradiated cells in a complex manner. However, experimental studies of intraoperative radiotherapy are limited. Intrabeam is a frequently used intraoperative radiotherapy device; we evaluated its effects on the proliferation, apoptosis, migration, and invasion of MCF-7 human breast cancer cells. We performed colony formation assays for cells irradiated with single radiation doses of 0 to 16 Gy. Other cells were irradiated with single radiation doses of 0 to 6 Gy and then continued to be cultured. We measured cell-cycle distributions and apoptosis rates 24 hours later, using flow cytometry, and performed wound-healing assays, Transwell tests, and terminal deoxynucleotidyl transferase–mediated 2′-deoxyuridine 5′-triphosphate nick-end labeling staining 4 weeks later. Colony formation assays showed no positive colonies from cells irradiated with doses of ≥6 Gy. In flow cytometry, the experimental groups had higher late-apoptosis/necrosis rates (P < .01) and higher percentages of cells arrested in G₁ phase (P < .01). Experimental groups also had much lower scratch-repair rates in the wound healing assay (P < .001) and higher apoptosis rates in the terminal deoxynucleotidyl transferase–mediated 2′-deoxyuridine 5′-triphosphate nick-end labeling assay (P < .05). In Transwell tests, the 4 Gy and 6 Gy groups had fewer invading cells than the control group (P < .05). Single-dose irradiation of 6 Gy with the Intrabeam device can effectively inhibit proliferation, migration, and invasiveness and promote apoptosis in MCF-7 cells with long-lasting effects.

Keratinocyte Carcinomas: Current Concepts and Future Research Priorities

Cutaneous squamous cell carcinoma (cSCC) and basal cell carcinoma (BCC) are keratinocyte carcinomas, the most frequently diagnosed cancers in fair-skinned populations. Ultraviolet radiation (UVR) is the main driving carcinogen for these tumors, but immunosuppression, pigmentary factors, and aging are also risk factors. Scientific discoveries have improved the understanding of the role of human papillomaviruses (HPV) in cSCC as well as the skin microbiome and a compromised immune system in the development of both cSCC and BCC. Genomic analyses have uncovered genetic risk variants, high-risk susceptibility genes, and somatic events that underlie common pathways important in keratinocyte carcinoma tumorigenesis and tumor characteristics that have enabled development of prediction models for early identification of high-risk individuals. Advances in chemoprevention in high-risk individuals and progress in targeted and immune-based treatment approaches have the potential to decrease the morbidity and mortality associated with these tumors. As the incidence and prevalence of keratinocyte carcinoma continue to increase, strategies for prevention, including effective sun-protective behavior, educational interventions, and reduction of tanning bed access and usage, are essential. Gaps in our knowledge requiring additional research to reduce the high morbidity and costs associated with keratinocyte carcinoma include better understanding of factors leading to more aggressive tumors, the roles of microbiome and HPV infection, prediction of response to therapies including immune checkpoint blockade, and how to tailor both prevention and treatment to individual risk factors and needs.

Radiation therapy techniques in the treatment of skin cancer: an overview of the current status and outlook

Nonmelanoma skin cancer (NMSC) is a major health concern due to its high incidence rate, its negative impact on the quality of life of patients as well as the associated economic burden to the healthcare system. Surgery is currently the primary treatment offered for skin cancer patients but not applicable or available in all cases. Radiation therapy (RT), with its long successful history in the management of cancer, has shown to be an effective alternative or complementary method in cutaneous oncology. Specifically, for dermatology applications, RT is very often the preferred option due to its favorable cosmetic results, besides the excellent control rate of the tumor. During the last 120 years since the introduction of treatments based on ionizing radiation, several techniques in this area have been developed. Radionuclide brachytherapy, electronic brachytherapy, X-ray therapies with kilovolt (kV) to megavolt (MV) photons and electron beam therapy are the established methods that are currently used on skin cancer patients. The purpose of this article is to overview these techniques and discuss the pros and cons of these methods in dermatology practices. Additionally, a new approach of beta RT of superficial skin tumors is discussed, which may offer exciting features in the management of NMSC.

Place de la radiothérapie dans le traitement du carcinome basocellulaire

Radiotherapy is an available but not well-known treatment for management of basal cell carcinoma. National organizations have established that standard therapy is complete surgical removal and radiation therapy is an option for inoperable tumors or those where the post-operative defect would be cosmetically disfiguring or functionally disabling. These therapeutic options, with histological sample, should be considered in the multidisciplinary management of patients with basal cell carcinoma. There are several types of radiotherapy: external radiation or interstitial brachytherapy, unfortunately, there is no consensus in the literature and the range of radiation regimens in common use is large. Very few randomized studies have been conducted to defi the optimum treatment in terms of recurrence rate, cosmetic outcome and side-eff In most of studies, the overall local control rate was between 80-100% and over 90% of patients reported good or excellent cosmetic outcome. Side-eff of radiotherapy most commonly reported are minor but in young patients one must be alert to the theoretical possibility of the induction of secondary malignancies. Cet article fait partie du numéro supplément Prise en charge des carcinomes basocellulaires difficiles à traiter réalisé avec le soutien institutionnel de Sun Pharma.

New developments in the treatment of basal cell carcinoma: update on current and emerging treatment options with a focus on vismodegib

Basal cell carcinoma (BCC) is the most common form of skin cancer worldwide. Although most BCCs can be treated by relatively simple surgical or nonsurgical methods, some patients with BCC may eventually develop advanced disease which can either be locally destructive or even include metastatic spread. The present review summarizes the current literature on the treatment of both early and advanced BCC with a focus on the hedgehog inhibitor vismodegib which has become an integral part of the management of patients with advanced BCC since its regulatory approval in 2012.

[Basal cell carcinoma of the face and scalp : An update on treatment options]

The treatment of malignant tumors of the facial skin is an important part of the specialty oral and maxillofacial surgery. In two successive CME articles, important aspects of frequent entities are dealt with for the facial area. The current article deals with basal cell carcinoma, the most common localization of which is by far the facial area. Surgical resection is the treatment modality of first choice. A risk-adapted approach involving complete histopathological margin assessment is recommended for basal cell carcinoma at risk for recurrence or aggressive spread in order to spare healthy skin and to control subclinical tumor growth. There are specific caveats for non-surgical treatment options, such as topical medication, destructive procedures, and radiotherapy. This article describes indications and treatment methods with a focus on surgical resection techniques.

Recent advances in field cancerization and management of multiple cutaneous squamous cell carcinomas

Cutaneous squamous cell carcinoma (SCC) is among the most common cancers in humans, and many patients with SCC will develop multiple tumors within their lifetime. The field cancerization concept, originally proposed over 60 years ago, hypothesized that multiple primary cancers may arise simultaneously and coexist with subclinical precursor lesions within a defined field. Genetic sequencing of SCC and precursor lesions has identified what may be the earliest clonal proliferations in SCC development and confirmed that field cancerization in the skin is mediated by ultraviolet radiation. For patients with multiple SCCs and severe actinic damage, treatment of precursor lesions within a cancerized field can decrease the risk of subsequent cancer development. Sunblock is an effective intervention for field cancerization, even in patients with established disease. There is now direct evidence that field therapy with topical 5-fluorouracil is effective in reducing the incidence of subsequent SCC, and there is indirect evidence suggesting that topical imiquimod, topical ingenol mebutate, and photodynamic therapy are similarly effective. There is limited direct evidence to show that systemic acitretin or nicotinamide can decrease incident SCC in patients with field cancerization. In this review, an approach to the management of patients with multiple SCCs and field cancerization is presented along with the rationale to support field-directed therapy.

The Value of Adjuvant Radiotherapy in Cutaneous Squamous Cell Carcinoma: A Review

Cutaneous squamous cell carcinoma (cSCC) is the second most common cancer in humans and its incidence is rising. Although surgery is the treatment of choice for cSCC, postoperative adjuvant radiotherapy has an important role in local and locorregional disease control. In this review, we analyze the value of postoperative radiotherapy in the management of high-risk cSCC (in particular, cases with perineural invasion), cSCC with positive surgical margins, and locally advanced cSCC (with parotid gland and/or lymph node metastasis).

Intraoperative Radiotherapy With INTRABEAM: Technical and Dosimetric Considerations

Purpose

We evaluate dose characteristics and clinical applications of treatment accessories used in intraoperative radiotherapy (IORT) and make site-specific recommendations for their optimal use.

Methods and materials

Dose measurements were performed for a low energy (50 kV) X-ray INTRABEAM source. For spherical, flat, surface, and needle applicators, the following dosimetric parameters were measured: depth-dose (DD) profiles, surface dose (Ds), output factors (OF), and target dose homogeneity (DH). Optical density versus exposure calibration films were employed to obtain 2-dimensional dose distributions in planes parallel and perpendicular to beam direction. Film results were verified via repeat dose measurements with a parallel-plate ionization chamber in a custom water tank. The impact of applicator design on dose distributions was evaluated.

Results

Spherical applicators are commonly used for treating the inner-surface of breast lumpectomy cavity. Flat and surface applicators provide uniform planar dose for head and neck, abdomen, and pelvis targets. Needle applicators are designed for kypho-IORT of spinal metastasis. Typically, larger applicators produce a more homogeneous target dose region with lower surface dose, but require longer treatment times. For 4-cm diameter spherical, flat, and surface applicators, dose rates (DR) at their respective prescription points were found to be: 0.8, 0.3, and 2.2 Gy/min, respectively. The DR for a needle applicator was 7.04 Gy/min at 5 mm distance from the applicator surface. Overall, film results were in excellent agreement with ion-chamber data.

Conclusion

IORT may be delivered with a variety of site-specific applicators. Appropriate applicator use is paramount for safe, effective, and efficient IORT delivery. Results of this study should help clinicians assure optimized target dose coverage and reduced normal tissue exposure.

Efficacy of hypofractionated radiotherapy in patients with non-melanoma skin cancer: Results of a systematic review

Radiation oncologists are increasingly tasked with the management of elderly patients with non-melanoma skin cancer, unsuitable for surgical intervention due to inoperable lesions and/or poor performance status. In this cohort, hypofractionated radiotherapy, delivered either daily, alternative daily or once weekly is highly effective. A systematic literature search was conducted of PUBMED, MEDLINE and EMBASE databases using the algorithm ('radiotherapy' OR 'radiation therapy' OR 'brachytherapy') AND ('hypofraction' OR 'hypofractionated' OR 'hypofractionation') AND ('skin neoplasms' OR 'carcinoma' OR 'malignancy') AND ('skin' OR 'epidermis' OR 'epidermal' OR 'cutaneous'). Forty relevant publications (1983-2017) encompassing 12,337 irradiated lesions were retrieved. Studies documented a mean age of 71.73 years and male predilection (54.5%). Both external beam radiotherapy and brachytherapy were utilized. Tumour subtype was squamous cell carcinoma (23.5%), basal cell carcinoma (75.2%) or others (1.3%). Irradiated lesions were primary (or denovo) (92.6%), located on the head and neck (95.7%) and received definitive therapy (96.5%). Analysis demonstrated a mean weighted total radiotherapy dose (38.15 Gy), dose per fraction (7.95 Gy) and treatments per week (2.98). Despite significant heterogeneity in the study population, the radiotherapy delivered and follow-up, local recurrence rate (crude or Kaplan-Meier analysis) did not exceed 7.9% in all but three of the 36 publications providing these data. Twenty-nine publications documented local control exceeding 90%. There is a body of evidence documenting the efficacy of hypofractionated radiotherapy as an option that confers no obvious disadvantage in local control when compared to traditional more protracted radiotherapy schedules.