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

Epidemiological and clinical analysis of exposure-related factors in non-melanoma skin cancer: A retrospective cohort study

BACKGROUND

The incidence of non-melanoma skin cancers (NMSCs) increased over last decades, probably due to environmental concerns or to the increase of frail patients with age related comorbidities. Currently, the relationship of increasing global skin cancer rates with increased ultraviolet radiations (UVRs) resulting from stratospheric ozone depletion, global warming, and air pollution from fossil-fuel combustion.

AIMS

We conducted a retrospective epidemiological study including 546 NMSC patients managed at the Dermatology Unit of the Tor Vergata Hospital to highlight different trends of sun exposure or different comorbidities.

METHODS

Descriptive and inferential statistical analyses were performed to evidence differences between continous variable and Spearman rank test for dicotomical variables. Charlson Comorbidity Index was calculated to obtain the 10-years survival rate in order to identify the mean comorbidity burden of our patients.

RESULTS

Considering patients with comorbidities (73.81%), actinic keratoses (AKs) was the most frequent lesion. In patients with a history of previous melanoma, basal cell carcinoma (BCC) was predominant (ANOVA test, p < 0.05) with a statistically significant correlation (rho = 0.453; p < 0.01). Squamous cell carcinoma (SCC) showed a higher rate in arterial hypertension patients, followed by the chronic heart failure and hematologic neoplasms (60%, 29.7% and 32.1%, respectively) groups. Men were more affected than women, representing 61.54% of patients. Chronic sun exposure is directly correlated with SCC rho = 0.561; p < 0.01), whereas BCC correlated with a history of sunburns (rho = 0.312; p < 0.05).

CONCLUSIONS

History of photo-exposition had an important role on NMSC development especially for work or recreational reasons. Sex, age, and presence of comorbidities influenced different NMSC types. BCC was more frequent in younger patients, associated with melanoma and sunburns. The presence of SCC is associated with older patients and the hypertension group. AKs were diagnosed predominantly in oldest men, with a chronic sun-exposure history, and hematologic neoplasms group.

Brachytherapy and 3D printing for skin cancer: A review paper

Brachytherapy is a type of radiation therapy, in which a radiation source is placed directly or close to a tumor. It is commonly used to treat skin cancer, and enables precise irradiation treatment of affected area (planning target volume - PTV) while minimizing exposure dose to surrounding healthy tissue (organs at risk - OARs). Recently, the use of 3D printing has begun revolutionizing brachytherapy, as it allows manufacturing of custom-designed applicators for unique shape of skin topography, tumor, and surrounding tissues. Outcome of the combination of 3D printing and brachytherapy has several advantages over traditional treatment planning methods. Some of the advantages are intuitive, whereas others can be concluded from a literature overview as follows: 1) Possibility of developing patient-specific applicators that precisely match the shape of tumor area; 2) Reduction of the time required for applicator production, especially when custom-made devices are needed; 3) Reduction of manufacturing costs; 4) Treatment procedures improvement; 5) Improvement of safety measures accelerated by the development of smart materials (e.g., polymer filaments with admixture of heavy elements); 6) Possibility of nearly instant adjustment into tumor treatment (applicators can be changed as the tumor is changing its shape); and 7) Applicators designed to securely fit to treatment area to hold radioactive source always in the same place for each fraction. Consequently, tumor-provided dose is accurate and leads to effective treatment. In this review paper, we investigated the current state-of-the-art of the application of 3D printing in brachytherapy. A number of existing reports were chosen and reviewed in terms of printing technology, materials used, treatment effectiveness, and fabrication protocols. Furthermore, the development of future directions that should be considered by collaborative teams bridging different fields of science, such as medicine, physics, chemistry, and material science were summarized. With the indicated topics, we hope to stimulate the innovative progress of 3D printing technology in brachytherapy.

Post-operative interventional radiotherapy (brachytherapy) in advanced ocular surface and eyelid tumors as an alternative to surgical retreatment

PURPOSE

The main purpose of treatment of advanced ocular surface and periocular malignant tumors is to eradicate the tumor while trying to preserve visual function and aesthetics. Our purpose is to describe the outcome of a retrospective case series of 10 patients with advanced ocular surface and periocular tumors treated surgically in first instance and then with postoperative interventional radiotherapy (IRT/Brachiterapy).

MATERIALS AND METHODS

We describe the clinicopathological features, treatments and outcome, in a retrospective case series of 10 patients with advanced tumors involving ocular surface (staging ≥ T2) and eyelids (staging ≥ T3), with involvement of periocular and/or orbit tissues. Patients were first surgically treated, most of them with incomplete excision, and then underwent a post-operative interventional radiotherapy (IRT/Brachytherapy) as an alternative to more invasive and disfiguring surgical retreatment. Tumor location, risk factors, staging, histological features, and follow-up timing were analyzed.

RESULTS

Three patients had advanced eyelid basal cell carcinomas, 2 patients were diagnosed with eyelid and conjunctival squamous cell carcinomas, 3 as sebaceous carcinomas, and 2 as primary conjunctival melanomas. The mean follow-up time from IRT to last clinical follow-up was 58.6 weeks, range 28.4-168 (median 43.65, IQR 28.9-72.9). Two patients - one with ocular surface SCC, the other with conjunctival melanoma - had a local recurrence 23.4 and 40,9 weeks after IRT, respectively. An overview of the current knowledge on adjuvant or post-operative IRT is also provided.

CONCLUSIONS

IRT can be considered an effective therapeutic option to avoid more invasive surgical retreatment in advanced tumors involving eyelids and ocular surface.

Dosimetric impact of applying a model-based dose calculation algorithm for skin cancer brachytherapy (interventional radiotherapy)

Purpose

Brachytherapy (BT, interventional radiotherapy) is a well-established radiotherapy technique capable of delivering high doses to tumors while sparing organs at risk (OARs). Currently, the clinically accepted dose calculation algorithm used is TG-43. In the TG-186 report, new model-based dose calculation algorithms (MBDCA), such as Elekta's advanced collapsed cone engine (ACE), have been introduced, although their clinical application is yet to be fully realized. This study aimed to investigate two aspects of TG-186: firstly, a comparison of dose distributions calculated with TG-43 and TG-186 for skin tumors; and secondly, an exploration of the impact of using a water bolus on the coverage of clinical target volume (CTV) and OARs.

Material and methods

Ten treatment plans for high-dose-rate IRT were developed. All plans were initially calculated using the TG-43 algorithm, and were subsequently re-calculated with TG-186. In addition, one of the treatment plans was assessed with both TG-43 and TG-186, using 10 different water bolus thicknesses ranging from 0 to 5 cm. To assess dose variations, the following dose-volume histogram (DVH) parameters were compared: D2cc and D0.01cc for OARs, and V150, V100, V95 and V90 for CTV coverage.

Results and conclusions

The average dosimetric results for CTV and OARs, as calculated by both algorithms, revealed statistically significant lower values for TG-186 when compared with TG-43. The presence of a bolus was observed to enhance CTV coverage for the TG-186 algorithm, with a bolus thickness of 2 cm being the point at which ACE calculations matched those of TG-43. This study identified significant differences in dosimetric parameters for skin tumors when comparing the TG-43 and TG-186 algorithms. Moreover, it was demonstrated that the inclusion of a water bolus increased CTV coverage in TG-186 calculations.

Advanced non-melanoma skin cancer in elderly patients: When surgery says NO, interventional radiotherapy (brachytherapy) says YES

Purpose

The prevalence of non-melanoma skin cancer (NMSC) increases, especially in older adults with comorbidities, narrowing radical treatment options. About 5% of skin cancer patients are diagnosed with an advanced stage, which impairs daily functioning. The study was to present a retrospective summary of elderly patients unfit for surgery and treated with various brachytherapy (BT) techniques tailored individually for locally advanced NMSCs in a reference BT department. Clinical case presentations supported the findings.

Material and methods

Inoperable patients older than 75 years presenting with advanced pathologically confirmed NMSCs were retrospectively identified. All cases were individually assessed, and the best suiting radical treatment option was chosen, including contact, interstitial, or hybrid high-dose-rate (HDR) or pulsed-dose-rate (PDR) BT. Doses ranging from 45 to 60 Gy were administered to clinical target volume (CTV) in different time schedules. All patients were closely followed-up until complete remission.

Results

Ten elderly patients (mean age, 84 years) with differently located locally advanced NMSCs (all staged T3) were treated between 2007 and 2022. Six basal and four squamous cell carcinoma cases showed most painful symptoms as well as bleeding and exudation. Six patients underwent HDR-BT and four PDR-BT. Six patients had superficial, and four interstitial or hybrid applications. All patients completed the intended protocols. Median follow-up was 8.5 months (range, 3-35 months). Six out of ten patients died from other reasons before analysis. All case data were presented in the text and respective figures.

Conclusions

Advanced NMSCs in elderly patients are challenging in terms of cure. Inoperable cases may be referred for feasible and locally effective interventional radiotherapy (BT). Individually tailored BT leads to an excellent disease control, function sparing, symptoms release, and quality of life improvement. Large treated volumes are related to prolonged healing. BT should be discussed in a multidisciplinary tumor board regarding older patients with symptomatic functions affecting advanced NMSCs.

KIT 1 (Keep in Touch) Project-Televisits for Cancer Patients during Italian Lockdown for COVID-19 Pandemic: The Real-World Experience of Establishing a Telemedicine System

To evaluate the adoption of an integrated eHealth platform for televisit/monitoring/consultation during the COVID-19 pandemic.

METHODS

During the lockdown imposed by the Italian government during the COVID19 pandemic spread, a dedicated multi-professional working group was set up in the Radiation Oncology Department with the primary aim of reducing patients' exposure to COVID-19 by adopting de-centralized/remote consultation methodologies. Each patient's clinical history was screened before the visit to assess if a traditional clinical visit would be recommended or if a remote evaluation was to be preferred. Real world data (RWD) in the form of patient-reported outcomes (PROMs) and patient reported experiences (PREMs) were collected from patients who underwent televisit/teleconsultation through the eHealth platform.

RESULTS

During the lockdown period (from 8 March to 4 May 2020) a total of 1956 visits were managed. A total of 983 (50.26%) of these visits were performed via email (to apply for and to upload of documents) and phone call management; 31 visits (1.58%) were performed using the eHealth system. Substantially, all patients found the eHealth platform useful and user-friendly, consistently indicating that this type of service would also be useful after the pandemic.

CONCLUSIONS

The rapid implementation of an eHealth system was feasible and well-accepted by the patients during the pandemic. However, we believe that further evidence is to be generated to further support large-scale adoption.

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.

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. 

ORIFICE (Interventional Radiotherapy for Face Aesthetic Preservation) Study: Results of Interdisciplinary Assessment of Interstitial Interventional Radiotherapy (Brachytherapy) for Periorificial Face Cancer

(1) Background: Periorificial face cancer (PFC), defined as both squamous cell carcinoma (SCC) and basal cell carcinoma (BCC) arising around the eyelids, the nose vestibule and the lips, has very high incidence rates worldwide. The aim of our retrospective analysis, focusing on local control (LC) and patients’ degree of satisfaction with the cosmetic outcome, is to present the results of a single institutional series of patients affected by PFC and treated by interventional radiotherapy (brachytherapy–IRT). (2) Methods: We retrospectively evaluated patients affected by PFC who were treated at our Interventional Oncology Center (IOC) with interstitial IRT from 2012 to 2021 with doses and volumes specific for each subsite considered. (3) Results: We report the results of 40 patients affected by PFC and treated by HDR interstitial IRT. The median follow-up was 24 months. The actuarial 3-year LC was 94%. Regarding patients’ satisfaction, we found that 93% of patients were satisfied and only 7% of patients were not completely satisfied with the final cosmetic result. (4) Conclusions: Interstitial HDR IRT could be an effective therapeutic option providing adequate disease control and preventing potentially disfiguring surgical approaches. More numerous and standardized studies are warranted to confirm the available evidence.

Contact skin radiotherapy (brachytherapy) for the treatment of non-melanoma skin cancers during COVID-19 pandemic

In the context of the SARS-CoV-2 pandemic, it is important to ensure the quality of cancer treatment as well as patients and health professionals' safety. Individual-based treatment options should be considered in patients with advanced epithelial skin cancer, who are typically elderly and frail. Aim of this study was to assess feasibility and safety of Contact Skin Radiation Therapy (CSRT) to treat basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) during SARS-CoV-2 pandemic. Patients with advanced and difficult-to-treat BCC or SCC were discussed at skin multidisciplinary tumor board (S-MDTB) from February the 21st to May the 4th (phase 1 Italian Pandemic) and retrospectively analyzed. Patient's triage following internal recommendations was daily performed. CSRT was delivered in 8 fractions of 5 Gy each, twice a day. Beyond the clinical outcomes, treatment success indicators, such as the completion of CSRT without SARS-CoV-2 occurrence, were identified to evaluate the feasibility of CSRT during pandemic. A post-treatment psychological assessment regarding patient's safety perception was performed. Six male patients (median age 80 years; range 62-92) with histologically confirmed BCC or SCC were treated with CSRT. Complete clinical remission was achieved in 5/6 patients (83.4%). No high-grade acute toxicities occurred during treatment. No patients or healthcare personnel developed SARS-CoV-2 infection. All the treatment success indicators were achieved. CSRT represents a safe, and feasible treatment option even during the pandemic emergency period. Hypofractionation could be an option to reduce total number of fractions and, consequently, infective risk exposition.

Volumetric Modulated Arc Therapy Capabilities for Treating Lower-Extremity Skin Affected by Several Merkel Cell Carcinoma Nodules: When Technological Advances Effectively Achieve the Palliative Therapeutic Goal while Minimising the Risk of Potential Toxicities

The peculiar and rare clinical condition below clearly requires a customized care approach in the context of personalized medicine. An 80-year-old female patient who was subjected in 2018 to surgical removal of a cutaneous Merkel cell carcinoma (MCC) nodule located on the posterior surface of the left thigh and to three subsequent palliative radiotherapy treatments developed a fourth relapse in October 2020, with fifteen nodular metastases located in the left thigh and leg. Since the overall macroscopic disease was still exclusively regionally located and microscopic spread was likely extended also to clinically negative skin of the thigh and leg, we performed an irradiation of the whole left lower extremity. For this purpose the total target (65.5 cm) was divided into three sub-volumes. Dose prescription was 30 Gy in 15 daily fractions. A sequential boost of 10 Gy in 5 daily fractions was planned for macroscopic nodules. Plans were calculated by means of volumetric modulated arc therapy (VMAT) with the field overlap technique. Thanks to this, we obtained a homogeneous dose distribution in the field junction region; avoidance structures were delineated in the central part of the thigh and leg with the aim of achieving an optimal superficial dose painting and to reduce bone exposure to radiation. This case study demonstrates that VMAT allows for a good dose coverage for circumferential cutaneous targets while sparing deeper organs at risk. A reproducible image-guided set-up is fundamental for an accurate and safe dose delivery. However, local treatments such as radiotherapy for very advanced MCC of the lower extremities might have limited impact due to the high probability of systemic progression, as illustrated in this case. Radiation is confirmed as being effective in preventing MCC nodule progression toward skin wounding.

Mambalgin-2 Inhibits Growth, Migration, and Invasion of Metastatic Melanoma Cells by Targeting the Channels Containing an ASIC1a Subunit Whose Up-Regulation Correlates with Poor Survival Prognosis

Melanoma is an aggressive cancer characterized by the acidification of the extracellular environment. Here, we showed for the first time that extracellular media acidification increases proliferation, migration, and invasion of patient-derived metastatic melanoma cells and up-regulates cell-surface expression of acid-sensitive channels containing the ASIC1a, α-ENaC, and γ-ENaC subunits. No influence of media acidification on these processes was found in normal keratinocytes. To control metastatic melanoma progression associated with the ASIC1a up-regulation, we proposed the ASIC1a inhibitor, -mambalgin-2 from Dendpoaspis polylepis venom. Recombinant analog of mambalgin-2 cancelled acidification-induced proliferation, migration, and invasion of metastatic melanoma cells, promoted apoptosis, and down-regulated cell-surface expression of prooncogenic factors CD44 and Frizzled 4 and phosphorylation of transcription factor SNAI. Confocal microscopy and affinity purification revealed that mambalgin-2 interacts with heterotrimeric ASIC1a/α-ENaC/γ-ENaC channels on the surface of metastatic melanoma cells. Using the mutant variant of mambalgin-2 with reduced activity toward ASIC1a, we confirmed that the principal molecular target of mambalgin-2 in melanoma cells is the ASIC1a subunit. Bioinformatic analysis confirmed up-regulation of the ASIC1 expression as a marker of poor survival prognosis for patients with metastatic melanoma. Thus, targeting ASIC1a by drugs such as mambalgin-2 could be a promising strategy for metastatic melanoma treatment.

Correlation between Autofluorescence Intensity and Histopathological Features in Non-Melanoma Skin Cancer: An Ex Vivo Study

Simple Summary

Non-melanoma skin cancers (NMSC) are the most prevalent neoplasms worldwide, especially in the Caucasian population. Radical surgical excision is considered the therapeutic gold standard, while incomplete tumor removal is invariably associated with recurrence and the need for reintervention. Autofluorescence (AF) spectroscopy has recently been investigated for early diagnosis of NMSC and assessment of tumor margins. Understanding changes in AF intensity in association with peculiar histological features could improve the diagnostic accuracy of skin fluorescence spectroscopy. The main goal of our work was to investigate the correlation between the intensity of cutaneous AF and the histopathological features of NMSC. The intensity of fluorescence emission in tissues obtained from NMSC samples was approximately 4 times lower than that in healthy conditions. In fact, mean AF intensity for BCC group was 4.5 and 4.4 for SCCs, with further variability being recorded according to histopathologic subtypes. Histopathological features such as hyperkeratosis, neoangiogenesis, fibrosis and elastosis are statistically associated with a decrease in AF intensity. Our data suggest that such tissue alterations could be responsible for the difference in AF emission between neoplastic and healthy tissue. These results support the potential application of AF as a useful non-invasive diagnostic tool for NMSCs.

Abstract

Non-melanoma skin cancer (NMSC) is the most common malignant tumor affecting fair-skinned people. Increasing incidence rates of NMSC have been reported worldwide, which is an important challenge in terms of public health management. Surgical excision with pre-operatively identified margins is one of the most common and effective treatment strategies. Incomplete tumor removal is associated with a very high risk of recurrence and re-excision. Biological tissues can absorb and re-emit specific light wave-lengths, detectable through spectrophotometric devices. Such a phenomenon is known as autofluorescence (AF). AF spectroscopy has been widely explored for non-invasive, early detection of NMSC as well as for evaluation of surgical margins before excision. Fluorescence-aided diagnosis is based on differences in spectral characteristics between healthy and neoplastic skin. Understanding the biological basis of such differences and correlating AF intensity to histological features could improve the diagnostic accuracy of skin fluorescence spectroscopy. The primary objective of the present pre-clinical ex vivo study is to investigate the correlation between the intensity of cutaneous AF and the histopathological features of NMSC. Ninety-eight lesions suggestive for NMSCs were radically excised from 75 patients (46 M; 29 F; mean age: 79 years). After removal, 115 specific reference points on lesions (“cases”; 59 on BBC, 53 on SCC and 3 on other lesions) and on peri-lesional healthy skin (controls; 115 healthy skin) were identified and marked through suture stitches. Such reference points were irradiated at 400–430 nm wavelength, and resulting emission AF spectra were acquired through spectrophotometry. For each case, AFIR (autofluorescence intensity ratio) was measured as the ratio between the number of photons emitted at a wavelength ranging between 450 and 700 nm (peak: 500 nm) in the healthy skin and that was captured in the pathological tissue. At the histological level, hyperkeratosis, neoangiogenesis, cellular atypia, epithelial thickening, fibrosis and elastosis were quantified by light microscopy and were assessed through a previously validated grading system. Statistical correlation between histologic variables and AFIR was calculated through linear regression. Spectrometric evaluation was performed on 230 (115 cases + 115 controls) reference points. The mean AFIR for BCC group was 4.5, while the mean AFIR for SCC group was 4.4 and the fluorescence peaks at 500 nm were approximately 4 times lower (hypo-fluorescent) in BCCs and in SCCs than in healthy skin. Histological variables significantly associated with alteration of AFIR were fibrosis and elastosis (p < 0.05), neoangiogenesis, hyperkeratosis and epithelial thickening. Cellular atypia was not significantly associated with alteration of AFIR. The intensity of fluorescence emission in neoplastic tissues was approximately 4 times lower than that in healthy tissues. Histopathological features such as hyperkeratosis, neoangiogenesis, fibrosis and elastosis are statistically associated with the decrease in AFIR. We hypothesize that such tissue alterations are among the possible biophysical and biochemical bases of difference in emission AF between neoplastic and healthy tissue. The results of the present evaluation highlighted the possible usefulness of autofluorescence as diagnostic, non-invasive and real-time tool for NMSCs.