Predictive factors of vulvar melanoma outcomes

This study investigated the factors predictive of survival of patients with vulvar melanoma (VM). Researchers suggested that tumor thickness and mitotic rate (a measure of how fast cancer cells are dividing and growing) are strong predictors of VM outcomes. 

VM affects 1.08 to 1.36 per million women every year in the United States. Patients are diagnosed under the American Joint Committee on Cancer (AJCC) guidelines for primary cutaneous (skin) melanoma. However, melanomas that develop on mucosal sites, such as the sinuses or vulva, have different characteristics. It remains unclear whether these guidelines are also appropriated for VM patients. 

The objective of this study was to investigate the factors that predict survival in VM patients.

This study included information about 100 women, collected from one American institution. Overall survival (OS; time from treatment to death by any cause) and disease-specific survival (DSS; time from treatment to death by VM) were determined. The average follow-up was 67.8 months. 

The average OS was 73.5 months.  The average DSS was 74.2 months.

Tumor thickness greater than 4 mm was associated with a 3.97 times lower OS and a 5.77 times worse DSS when compared with a tumor thickness of 1 mm or less. A mitotic rate of 2 mm² or more was associated with a 3.36 times lower OS and with a 4.44 times worse DSS when compared to a mitotic rate of less than 2 mm².

This study suggested that tumor thickness and mitotic rate are strong predictors of VM outcomes. The authors suggested that these factors could be included with the AJCC guidelines when staging VM.