Squamous cell carcinoma of the vulva in Brazil: prognostic importance of host and viral variables.

BACKGROUND

Certain clinicopathologic features of vulvar squamous cell carcinoma have been correlated with adverse prognosis. However, few large-scale studies have addressed their role in patient survival. This study examined the relationship between multiple variables and prognosis in a large group of vulvar cancers in Brazil.

METHODS

One hundred eighty-four Brazilian women with vulvar carcinoma were studied and the following variables recorded: age, pathologic TNM stage, survival, histologic grade, tumor histologic pattern, invasion pattern, tumor thickness, and tissue stromal and inflammatory response. Human papillomavirus (HPV) was detected by polymerase chain reaction amplification of extracted archival DNA. Data were analyzed using Cox proportional hazards modeling.

RESULTS

After controlling for age, the probability of cancer survival decreased with increasing age, stage, grade, and tumor thickness, a fibromyxoid stromal response, infiltrative growth pattern, and basaloid histologic pattern. With the exception of fibromyxoid stromal response, each of these variables remained prognostically significant after adjustment for several other predictors in a multivariate model. Women whose tumors displayed a basaloid pattern were 3.5 times as likely to die from cancer than those with keratinizing tumors [hazard ratio (HR) = 3.5, 95% CI(1.3-9.2)]. An infiltrative invasion pattern strongly increased the probability of cancer death [HR = 4.6, 95% CI(1.9,11.4)]. HPV status did not influence survival, despite its association with basaloid histology.

CONCLUSIONS

Previously reported associations of negative HPV status and fibromyxoid response with adverse prognosis in vulvar cancer were not confirmed by multivariate analysis. Basaloid variants, and particularly diffusely infiltrative tumors, carry an adverse prognosis.