Twenty-eight patients with ovarian carcinoma received 555 MBq of labeled chromic phosphate (P-32) intraperitoneally. Indications for treatment included a high-grade tumor, extracapsular involvement, positive cytologic findings, or residual tumor. Fifteen patients (group 1) had stage I, II, or III completely resected tumor; 13 patients (group 2) had microscopic or less than 3-mm lesions at second-look laparotomy following combination chemotherapy. A major complication occurred in one patient; two patients had minor complications. Overall, 24 of 28 patients (85.7%) were alive at 11-77 months; 23 (82.1%) had no evidence of tumor. Fifteen of 15 (100%) group 1 patients and eight of 13 (61.5%) group 2 patients did not have tumor relapse after 30 months and 28 1/2 months, respectively. P-32 was found to be an effective adjuvant treatment in a select group of patients with ovarian carcinoma who were at high risk for intraabdominal recurrence.