Stereotactic body radiation therapy is beneficial for a subgroup of patients with urothelial cancer and solitary metastatic disease: a single institution real-world experience.

BACKGROUND: Standard treatment options for patients with metastatic urothelial cancer (mUC) include systemic platinum-based chemotherapy, immunotherapy, antibody-drug-conjugates, and targeted therapy. Oligometastatic disease (OMD) may be an intermediate state between localized and generalized cancer. The best treatment strategy for OMD and oligoprogressive (OPD) disease is poorly studied in mUC but local stereotactic body radiation therapy (SBRT) could be an option to avoid or delay systemic treatment. The aim of this study was to assess the efficacy and feasibility of SBRT given in a real-world patient population. METHODS: All patients with mUC treated with SBRT at Karolinska University Hospital, Stockholm, Sweden between 2009 and 2022 were included in this study. Baseline clinical characteristics, treatment data, SBRT dosimetry data and treatment outcome were collected retrospectively. The study endpoints were local control rate (LCR), progression-free-survival (PFS), overall survival (OS) and feasibility of SBRT. RESULTS: In total 39 patients were treated with SBRT. The median follow-up was 25.6 months. The LCR was 82%. PFS and OS were 4.1 and 26.2 months, respectively. Treatment was well tolerated; all patients but one (treatment related pain) completed the planned SBRT. Number of metastases irradiated with SBRT was significantly associated with outcome; patients with only one irradiated lesion had more favourable PFS compared to individuals with 2 or more metastases (HR 4.12, 95% CI: 1.81-9.38, p = 0.001). A subgroup of patients (15%) achieved a sustained long-term survival benefit and never required systemic treatments after SBRT. CONCLUSIONS: SBRT was well tolerated and associated with high LCR. A subpopulation of patients with single metastatic lesion achieved long-term OS and never required subsequent systemic treatment after SBRT. Prospective randomized studies are warranted to discover treatment predictive biomarkers and to investigate the role of SBRT in oligometastatic UC.

Extracellular microvesicle microRNAs as predictive biomarkers for targeted therapy in metastastic cutaneous malignant melanoma.

BACKGROUND: Mitogen activated-protein kinase pathway inhibitors (MAPKis) improve treatment outcome in patients with disseminated BRAFV600 mutant cutaneous malignant melanoma (CMM) but responses are of limited duration due to emerging resistance. Although extensive research in mechanisms of resistance is being performed, predictive biomarkers for durable responses are still lacking. We used miRNA qPCR to investigate if different levels of extracellular microvesicle microRNA (EV miRNA) in matched plasma samples collected from patients with metastatic IV BRAFV600 mutated CMM before, during and after therapy with MAPKis could serve as predictive biomarkers. MATERIALS AND METHODS: EV miRNAs were extracted from plasma samples from 28 patients collected before and during therapy, measured by quantitative PCR-array and correlated to therapy outcome. RESULTS: Increased levels of EV let-7g-5p during treatment compared to before treatment (EV let-7g-5p_delta) were associated with better disease control with MAPKis (odds ratio 8568.4, 95% CI = 4.8-1.5e+07, P = 0.000036). Elevated levels of EV miR-497-5p during therapy were associated with prolonged progression free survival (PFS) (hazard ratio = 0.27, 95% CI = 0.13-0.52, P <0.000061). CONCLUSIONS: EV miRNAs let-7g-5p and miR-497-5p were identified as putative novel predictive biomarkers of MAPKi treatment benefit in metastatic CMM patients highlighting the potential relevance of assessing EV miRNA during and after treatment to unravel novel mechanisms of resistance.

Stage-specific survival and recurrence in patients with cutaneous malignant melanoma in Europe - a systematic review of the literature.

BACKGROUND: Given the increasing incidence in cutaneous malignant melanoma (CMM) and the recent changes in the treatment landscape, it is important to understand stage-specific overall and recurrence-free survival patterns in Europe. Despite publications such as EUROCARE-5, there is limited information on stage-specific survival for CMM in Europe. METHOD: We carried out a systematic literature review to provide an up-to-date summary of stage-specific survival and recurrence-free survival patterns in patients with CMM in Europe. Studies were included if they were published in Medline during the past 12 years and included information on stage-specific survival and/or recurrence in CMM. RESULTS: Of the 8,749 studies identified, 26 studies were included, representing nine countries. Collectively, the studies covered a population of 152,422 patients and included data from 1978 to 2011. Randomized clinical trials and single-center observational studies comprised the most common study designs, including five large registry-based studies. Stage-specific information for survival and recurrence varied: 5-year overall survival: 95%-100% (stage I), 65%-92.8% (stage II), 41%-71% (stage III), and 9%-28% (stage IV); 5-year relapse-free survival was reported less frequently: 56% (stage II), and 28%-44% (stage III). Studies reporting survival by sentinel node (SN) status reported 5-year overall survival as 80%-95% for negative SN (stage I/II) and 35%-75% for positive SN (stage III) status; recurrence-free survival at 5 years: 76%-90% for negative and 35%-58% for positive SN status. Some studies included comparisons of survival by key patient sociodemographic characteristics, suggesting that these have a substantial influence on survival and recurrence estimates. CONCLUSION: The studies identified in this review show large variations in stage-specific overall and recurrence-free survival by study type and by country. Owing to differing study designs and populations, it is difficult to make detailed comparisons. Large population-based studies that include stage-specific survival and recurrence in Europe are therefore important.