32P following negative second-look laparotomy for epithelial ovarian cancer

Peritoneal seeding remains a prominent failure pattern in patients with invasive epithelial ovarian cancer, even following a pathologically negative second-look laparotomy (2LL). In an attempt to decrease the risk of peritoneal recurrence, we have treated patients with no clinical or histopathologic evidence of disease at 2LL with 15 mCi of chromic phosphate suspension intraperitoneally (32P).

Between 1973-1987, 69 patients with stages I-III invasive epithelial ovarian cancer in complete clinical remission were found to have no evidence of disease at 2LL. Fifty-one patients received intraperitoneal 32P. Thirty-five patients, otherwise eligible for 32P, did not receive it primarily due to other treatment protocols, peritoneal adhesions, or the recommendation that no further therapy be given following a negative 2LL. Patients in both groups were comparable with regard to stage, histology, grade, median age, residual disease following initial surgery, and chemotherapeutic regimen. The median follow-up for uncensored patients is 58 months (minimum, 18 months).

The 5-year actuarial disease-free survival rate from the date of 2LL was 86% for those receiving 32P and 67% for those not receiving 32P (P = 0.05). The corresponding 5-year overall survival rates were 90 and 78%, again favoring patients treated with 32P.

There were minimal acute side effects from 32P. Late adverse effects were similar in the two groups. Bowel complications were seen in 3 of 51 patients receiving 32P and 1 of 18 patients not receiving 32P.

We have found intraperitoneal 32P administration immediately after 2LL to be a safe and well-tolerated therapy. Our data suggest that 32P confers a survival advantage to patients with a pathologically negative 2LL. These findings suggest a continued role for second-look laparotomy with the use of 32P in selected patients.