Salvage re-irradiation in non-melanoma skin cancers: A multicenter analysis.

BACKGROUND AND PURPOSE: We conducted a multicentre real-world study to assess the outcomes of radical salvage re-irradiation for non-melanoma skin cancer (nMSC) recurrences following definitive or postoperative radiotherapy. MATERIALS AND METHODS: Data on patients treated between 2006 and 2022 with re-irradiation for nMSCs were retrospectively collected from five high-volume brachytherapy centers. The primary endpoint was local control (LC). Secondary endpoints included overall survival, progression-free survival, and adverse events (AEs). The Kaplan-Meier estimator and Cox Proportional-Hazards Model were utilised in the analysis. RESULTS: A total of 58 patients with a median age of 78.4 years with recurrences of previously irradiated nMSC in the head and neck region were included in the analysis. The majority had cutaneous basal cell carcinoma (BCC; 91.4%), and were irradiated with high-dose-rate brachytherapy (HDR-BT; 91.4%). The most common locations included the nasal region (36.2%) and external ear (18.9%). The 1-year LC was 73.1% and decreased to 41.7% at three years. The size of the re-irradiated lesion was the single independent prognostic factor in Cox analysis (per mm; HR 1.07; 95% CI 1.04-1.11; p < 0.001). Grade 3 or worse AEs were reported in 7 cases (12.1%). CONCLUSION: Re-irradiation for nMSCs, predominantly administered with brachytherapy for radiorecurrent BCC, is associated with high recurrence rates, and the risk of failure significantly increases with the size of the treated lesion. Re-irradiation could be an option for selected elderly patients with small, localised, inoperable recurrences after RT to achieve local control or defer systemic treatment; however, prospective trials are necessary to confirm its safety and efficacy.

Thermally boosted interstitial high-dose-rate brachytherapy in high-risk early-stage breast cancer conserving therapy - large cohort long-term results.

Background: Early-stage high-risk breast cancer (BC) is standardly treated with breast-conserving therapy (BCT), combined with systemic therapy and radiotherapy (RT) ± tumor bed boost, e.g., with interstitial high-dose-rate brachytherapy (HDR-BT). To improve local recurrence rate (LRR), BT radiosensitization (thermal boost, TB) with interstitial microwave hyperthermia (MWHT) may be an option. The paper aims to report a retrospective single-institutional study on 5- and 10-year local control (LC), distant metastasis-free survival (DMFS), disease-free survival (DFS), overall survival (OS), cosmetic outcome (CO), and late toxicity (fibrosis, fat necrosis) after thermally enhanced HDR-BT boost to the BC tumor bed. Materials and methods: In 2006-2018, 557 early-stage (I-IIIA) high-risk BC patients were treated with BCT. If indicated, they were administered systemic therapy, then referred for 40.0-50.0 Gy whole breast irradiation (WBI) and 10 Gy interstitial HDR-BT boost (group A). Eligible patients had a single MWHT session preceding BT (group B). Based on present risk factors (RF), medium-risk (1-2 RF) and high-risk subgroups (≥ 3 RF) were formed. Patients were standardly checked, and control mammography (MMG) was performed yearly. Breast cosmesis (Harvard scale) and fibrosis were recorded. LC, DMFS, DFS, and OS were statistically analyzed. Results: Out of 557 patients aged 57 years (26-84), 364 (63.4%) had interstitial HDR-BT boost (group A), and 193 (34.6%) were preheated with MWHT (group B). Patients in group B had a higher clinical stage and had more RFs. The median follow-up was 65.9. Estimated 5-year and 10-year LC resulted in 98.5% and 97.5%, respectively. There was no difference in LC, DMFS, DFS, and OS between groups A and B and between extracted high-risk subgroups A and B. Five- and ten-year OS probability was 95.4% and 88.0%, respectively, with no difference between groups A and B. Harvard criteria-based CO assessment revealed good/excellent cosmesis in 74.9-79.1%. Tumor bed hardening was present in 40.1-42.2%. Asymptomatic fat necrosis-related macrocalcifications were detected in 15.6%, more frequently in group B (p = 0.016). Conclusions: Thermally boosted or not, HDR-BT was locally highly effective as part of combined treatment. Five- and ten-year LC, DMFS, DFS, and OS were high and equally distributed between the groups, although TB was prescribed in more advanced one with more RFs. TB did not influence CO and fibrosis. TB added to late toxicity regarding asymptomatic fat necrosis detected on MMG.

SKIN-COBRA (Consortium for Brachytherapy data Analysis) ontology: The first step towards interdisciplinary standardized data collection for personalized oncology in skin cancer.

PURPOSE: The primary objective of the SKIN-COBRA (Consortium for Brachytherapy data Analysis) ontology is to define a specific terminological system to standardize data collection for non-melanoma skin cancer patients treated with brachytherapy (BT, interventional radiotherapy). Through ontological characterization of information, it is possible to find, isolate, organize, and integrate its meaning. MATERIAL AND METHODS: SKIN-COBRA is a standardized data collection consortium for non-melanoma skin patients treated with BT, including 8 cancer centers. Its ontology was firstly defined by a multicentric and multidisciplinary working group and evaluated by the consortium, followed by a multi-professional technical commission involving a mathematician, an engineer, a physician with experience in data storage, a programmer, and a software expert. RESULTS: Two hundred and ninety variables were defined in 10 input forms. There are 3 levels, with each offering a specific type of analysis: 1. Registry level (epidemiology analysis); 2. Procedures level (standard oncology analysis); 3. Research level (radiomics analysis). The ontology was approved by the technical commission and consortium, and an ad-hoc software system was defined to be implemented in the SKIN-COBRA consortium. CONCLUSIONS: Large databases are natural extension of traditional statistical approaches, a valuable and increasingly necessary tool for modern healthcare system. Future analysis of the collected multinational and multicenter data will show whether the use of the system can produce high-quality evidence to support multidisciplinary management of non-melanoma skin cancer and utilizing this information for personalized treatment decisions.

Adjuvant interstitial three-dimensional pulse-dose-rate-brachytherapy for lip squamous cell carcinoma after surgical resection.

PURPOSE: The purpose of this study was to report clinical outcomes of patients treated with pulse-dose-rate brachytherapy (PDR-BT) for lip cancer after insufficient surgery. MATERIAL AND METHODS: Twenty lip cancer patients were treated from January 2012 to September 2016. Primary treatment included surgery with or without reconstruction. All patients were diagnosed with squamous cell carcinoma, most of the tumors were pT1. Brachytherapy procedures were done after post-operative wound healing. Median of three plastic tubes were implanted using a free-hand technique. Two PDR-BT treatments were scheduled for every patient, with the gap of median 13 days. The planned dose was 0.8-1 Gy per pulse to the total dose of 50 Gy from two PDR-BT treatments. Patients were evaluated every 3-6 months. Follow-up time was counted from the last day of treatment to any event or last visit. Early and late toxicities were scored with RTOG scale. RESULTS: Average follow-up was 34.7 months (range, 12.7-67.6). Three- and five-year estimated disease-free survival was 95% and local control was 100%. One patient suffered from regional relapse in the submental region (IA lymph node group). Skin erythema or dry desquamation (grade 1) or wet desquamation (grade 2) was observed in 13 patients (65%) and one patient (5%), respectively. Six patients presented no acute toxicity. Moreover, there were no complications involving lip mucosa. All patients had grade 1 soft tissue fibrosis in the irradiated area, besides that, late toxicity included only skin complications. There were no significant factors associated with late toxicity ≥ grade 2. CONCLUSIONS: PDR-BT in the adjuvant treatment of the lip cancer yields high local control with low toxicity. Even patients with close margins after surgery (< 5 mm) should be considered as candidates for PDR-BT.