Background: Intraperitoneal radioactive phosphorus (phosphorus-32) has been used in ovarian cancer during the last three decades. In the current study, the survival results, the patterns of recurrence, morbidity rates, and phosphorus-32 distribution scintigrams were reviewed in 313 patients treated with phosphorus-32 colloid.
Methods: Between July 1982 and July 1988, 245 patients with epithelial ovarian carcinoma were treated with phosphorus-32 as primary adjuvant treatment; 59 patients received phosphorus-32 as consolidating therapy after negative results during second-look surgery and 9, after positive findings during second-look laparotomy. Fifty patients with negative second-look findings were assigned randomly to receive phosphorus-32 or no treatment. The phosphorus-32 distribution was studied by scintigraphic imaging in 297 patients.
Results: The actuarial 5-year crude survival rate was 81% in the group treated with phosphorus-32 adjuvantly and 79% in the group treated after second-look surgery. Crude and disease-free survival rates were similar in both groups randomized at second-look surgery to receive either phosphorus-32 or no treatment. Phosphorus-32 scintigraphy showed major isotopic accumulations in 48 (16%) patients. There were two deaths (0.6%), which, at least partly, could be attributed to the phosphorus-32 treatment. Small bowel obstruction without tumor recurrence occurred in 22 (7%) patients (13 treated surgically and 9 medically) and was not related to any patient characteristic, including phosphorus-32 distribution.
Conclusions: Phosphorus-32 therapy was associated with a considerable number of bowel complications. The occurrence of small bowel obstruction could not be predicted by any patient characteristic. Without an untreated observation group, the authors were unsure whether adjuvant phosphorus-32 treatment conferred a survival advantage.