Abstract

One hundred and ten patients with invasive squamous cell carcinoma of the vulva, treated primarily with surgery at Toronto General Hospital between 1970 and 1981, were studied to determine recurrence patterns and factors predictive of relapse and survival. The overall and cause-specific actuarial 5-year survival rates were 63 and 73%, respectively. Eleven factors were studied for their prognostic value. Only Stage and, within Stage II, tumor thickness and nodal status, were independently prognostic. Six relapses occured in 8 Stage II patients who had both positive nodes and tumor thickness > 5 mm (Unfavorable Stage II), compared to 0/17 with neither or just one factor present (favorable Stage II, P= 0.0002). These results were used to define a low-risk group (Stages I and favorable II) and a high-risk group (Stages III, IV and unfavorable II). In the low-risk group, 6/69 relapsed and the 10-year actuarial relapse-free rate was 88%. This was significantly different from the high-risk group, where 24/32 relapsed (P < 10^-6) and the 10-year relapse-free rate was only 11% (P < 0.00005). The recognition of these two prognostic groups brings the therapeutic challenges in vulvar cancer into clearer focus. In the low-risk group there is a need to reduce surgical morbidity without compromising cure rates. In the high-risk group, locoregional control rates must be improved in order to improve cure rates. As 27 of the 30 relapses in the high-risk group were confined to the vulva or groin, adjunctive radiotherapy might improve cure rates if used in these patients.