Patterns of distant metastases in vulvar cancer

Metastatic vulvar cancer is a rare disease. Information on metastatic patterns and corresponding prognosis or therapeutic approaches is scarce. We therefore analyzed pattern and course of metastatic disease in a large single center cohort.

All patients with primary squamous-cell cancer of the vulvar [n=391, median age: 60years (range 20-94)] treated at the Gynecological Cancer Center Hamburg-Eppendorf 1996-2013 were retrospectively evaluated for occurrence of distant metastasis. Furthermore, a systematic Medline database search was performed using the terms: 'vulvar cancer' AND 'metastasis', 'chemotherapy', 'patterns of recurrence', or 'prognosis'.

Out of 391 patients with primary squamous cell vulvar cancer, 20 patients (5.1%) eventually presented with distant metastases. In these 20 patients, median time to first diagnosis of metastasis after primary diagnosis was 13.4months (range 4-104). Often patients experienced one or more local recurrences before distant spread (12/20, 60.0%). Documented metastatic sites were lung (n=9), liver (n=7), bone (n=5), skin (n=4) and lymph-nodes (axillary/thoracic/paraaortic, n=3). The majority of patients presented with unilocal metastases (13/20, 65.0%). In univariate analysis tumor diameter, invasion depth, nodal status and number of metastatic lymph-nodes were identified predictive for occurrence of distant metastases. 2-year-overall-survival-rate after metastases of all metastatic patients was 11.3%; median survival from first diagnosis of metastases was 5.6months.

The occurrence of distant metastasis from vulvar cancer is a rare event with very limited prognosis. Further efforts, especially translational research will be crucial to identify prognostic markers as well as therapeutic targets to improve survival in these patients.