Electrochemotherapy (ECT) is an effective locoregional therapy for cutaneous melanoma metastases and has been safely combined with immune checkpoint inhibitors in preliminary experiences. Since ECT is known to induce immunogenic cell death, its combination with immune checkpoint inhibitors might be beneficial. In this study, we aimed to investigate the effectiveness of ECT on cutaneous melanoma metastases in combination with pembrolizumab. We undertook a retrospective matched cohort analysis of stage IIIC–IV melanoma patients, included in the International Network for sharing practices of ECT (InspECT) and the Slovenian Cancer Registry. We compared the outcome of patients who received the following treatments: (a) pembrolizumab alone, (b) pembrolizumab plus ECT, and (c) ECT. The groups were matched for age, sex, performance status, and size of skin metastases. The local objective response rate (ORR) was higher in the pembrolizumab-ECT group than in the pembrolizumab group (78% and 39%, p < 0.001). The 1 year local progression-free survival (LPFS) rates were 86% and 51% (p < 0.001), and the 1 year systemic PFS rates were 64% and 39%, respectively (p = 0.034). The 1 year overall survival (OS) rates were 88% and 64%, respectively (p = 0.006). Our results suggest that skin-directed therapy with ECT improves superficial tumor control in melanoma patients treated with pembrolizumab. Interestingly, we observed longer PFS and OS in the pembrolizumab-ECT group than in the pembrolizumab group. These findings warrant prospective confirmation.

Background: Increased level of serum S100B can serve as a marker of metastatic spread in patients with cutaneous melanoma (CM). In patients with elevated S100 B and/or clinical signs of disease progression PET-CT scan is a valuable tool for discovering metastases and planning treatment. The aims of this study were to determine whether regular measurements of serum S100B are a useful tool for discovering patients with CM metastases and to evaluate the diagnostic value of PET-CT during the follow-up. Methods: From September 2007 to February 2010, 115 CM patients included in regular follow up at the Institute of Oncology Ljubljana were appointed to PET-CT. There were 82 (71.3%) patients with clinical signs of disease progression and 33 (28.7%) asymptomatic patients with two subsequent elevated values of S100B. Sensitivity, specificity, positive and negative predictive value (PPV, NPV) of S100B and PET-CT were calculated using standard procedures. Results: Disease progression was confirmed in 81.7% of patients (in 86.5% of patients with clinical signs of disease progression and in 69.7% of asymptomatic patients with elevated S100B). Sensitivity, specificity, PPV and NPV of S100B was 33.8%, 90.9%, 96.0% and 17.5% in patients with clinical signs of disease progression. In 20.0% of patients increased serum S100B was the only sign of disease progression. Sensitivity and PPV of S100 in this group of patients were 100.0% and 69.7%. With PET-CT disease progression was diagnosed in 84.2% of symptomatic patients and in 72.7% of asymptomatic patients with elevated S100B. The sensitivity, specificity, PPV and NPV of PET-CT for symptomatic patients was 98.5%, 90.9%, 98.5% and 90.9% and 100%, 90.0%, 95.8% and 100% for asymptomatic patients with elevated S100. Conclusions: Measurements of serum S100B during regular follow-up of patients with CM are a useful tool for discovering disease progression in asymptomatic patients. The value of its use increases if measurements are followed by extended whole body PET-CT.

The population of elderly people is increasing and so is the population of breast cancer patients aged ≥80 years. The aim of our retrospective study was to identify independent prognostic factors for the duration of breast cancer-specific survival of surgically treated patients aged ≥80 years. The secondary aim was to determine the appropriate surgical treatment of breast cancer in patients aged ≥80 years. We reviewed the medical records of 154 patients aged ≥80 years with early-stage breast cancer (mean age 83 years) who underwent surgery at the tertiary cancer center in the period from 2000 to 2008. Tumor stage was pT1/pT2 and pT3/pT4 in 75% and 25%, respectively. Surgical treatment comprised: quadrantectomy (in 27%), mastectomy (in 73%), axillary dissection (in 57%), and sentinel lymph node biopsy (in 18%), while 25% of patients had no axillary surgery. During a median follow-up of 5.3 years, 31% of patients died of breast cancer, while 28% of patients died of other causes. Half of our patients with poorly differentiated breast cancer or estrogen receptor-negative tumor died of breast cancer. Multivariate statistical analysis showed that the pathological T-stage, pathological N-stage and estrogen receptors were independent prognostic factors for the duration of breast cancer-specific survival of patients. Short breast cancer-specific survival indicates that, in patients aged ≥80 years, breast cancer with metastases in axillary lymph nodes can be an aggressive disease.

To determine the frequency and type of RET mutation in Slovenian medullary thyroid cancer (MTC) patients and estimate the crude annual incidence of MTC in Slovenia. This referral-center retrospective analysis involved 186 MTC patients diagnosed between 1995 and 2015 and their relatives who underwent genetic counseling and testing. The crude incidence rate of MTC was estimated with the joinpoint regression analysis. Genomic DNA was isolated, and exons 10, 11, 13, 14, 15, and 16 of the RET proto-oncogene were amplified with polymerase chain reaction. Point mutations of the RET gene were detected by single-strand conformation analysis and DNA sequencing. Detected mutations were confirmed by restriction enzymes. The average crude annual incidence rate of MTC in Slovenia was 0.34/100,000. A germline mutation in the RET proto-oncogene was identified in 25.9% of MTC patients. The most frequently altered codons were codons 634 and 618, followed by codon 790, codon 804, and codon 918. Annual incidence increase and nation-specific frequency of RET mutations justify the future use of genetic counseling and testing of MTC patients in Slovenia.

Cutaneous melanoma is a highly aggressive form of skin cancer. The development of immune checkpoint inhibitors (ICIs) has revolutionized the management of advanced melanoma, led to durable responses, and improved overall survival. However, the success of ICIs in melanoma treatment is influenced by the tumor microenvironment (TME) which plays a critical role in regulating the immune response to the tumor. Understanding the mechanisms underlying this interaction is crucial to optimizing the efficiency of ICIs. Electrochemotherapy (ECT) has been shown to enhance the efficacy of ICIs in melanoma treatment by inducing tumor cell death and facilitating the release of tumor antigens which can subsequently be recognized and targeted by the immune system. Moreover, ECT has been reported to modulate the TME, leading to increased infiltration of immune cells and a more favorable immunological profile. In this review, we summarize the available knowledge of changes in TME after ECT of melanoma cutaneous metastasis and highlight the differences in tumor-infiltrating immune cells between immunocompetent and immunosuppressed organisms. In addition, we showed that ECT can be an effective and safe procedure for organ transplant recipients. Furthermore, repeated ECT may enhance immune activation and probably induce a bystander effect by trained immunity.