Evaluation of treatment, prognostic factors, and survival in 198 vulvar melanoma patients: Implications for clinical practice

Objective: To identify clinicopathological characteristics, treatment patterns, clinical outcomes and prognostic factors in patients with vulvar melanoma (VM). Materials & methods: This retrospective multicentre cohort study included 198 women with VM treated in eight cancer centres in the Netherlands and UK between 1990 and 2017. Clinicopathological features, treatment, recurrence, and survival data were collected. Overall and recurrence-free survival was estimated with the Kaplan-Meier method. Prognostic parameters were identified with multivariable Cox regression analysis. Results: The majority of patients (75.8%) had localized disease at diagnosis. VM was significantly associated with high-risk clinicopathological features, including age, tumour thickness, ulceration, positive resection margins and involved lymph nodes. Overall survival was 48% (95% CI 40–56%) and 31% (95% CI 23–39%) after 2 and 5 years respectively and did not improve in patients diagnosed after 2010 compared to patients diagnosed between 1990 and 2009. Recurrence occurred in 66.7% of patients, of which two-third was non-local. In multivariable analysis, age and tumour size were independent prognostic factors for worse survival. Prognostic factors for recurrence were tumour size and tumour type. Only the minority of patients were treated with immuno- or targeted therapy. Conclusion: Our results show that even clinically early-stage VM is an aggressive disease associated with poor clinical outcome due to distant metastases. Further investigation into the genomic landscape and the immune microenvironment in VM may pave the way to novel therapies to improve clinical outcomes in these aggressive tumours. Clinical trials with immunotherapy or targeted therapy in patients with high-risk, advanced or metastatic disease are highly needed