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The α-particle emitter 211 At was covalently coupled to 1.8 μm aminated monodisperse polymer particles (MDPP) and used to irradiate the intraperitoneal cavity in mice with disseminated tumour cells. Specific activity has previously been shown to influence the therapeutic efficacy of α-particle emitting compounds and the therapeutic efficacy of 211 At-MDPP with various specific activity was therefore investigated. Groups of mice (10 animals per group) were treated with intraperitoneal injections of 100 kBq of 211 At-MDPP with specific activities of 0.19, 0.55, 1.7, 5.0, IS, and 45 MBq/mg. A significantly prolonged survival was observed in the treated groups compared to the control group (from 19 to 26 days vs. 12 days, median). The difference in survival between the 211 At-MDPP treated groups was not significant, but some animals with short survival were observed in the groups that had received the 0.19, 15 and 45 MBq/mg preparations. K13 monoclonal antibody values, which are an indicator of tumour growth, were high in some animals in the 15 and 45 MBq/mg groups (day 7 values).

Cyclotron-produced 211At was distilled from a Bi metal target and coupled to N-succinimidyl-3-(trimethylstannyl)benzoate. The resulting N-succinimidyl-3-(211At)astatobenzoate was thereafter coupled to aminated monosized polymer particles with a diameter of 1.8 μm. The total time elapsed from the end of the cyclotron irradiation until the final product was prepared was about 2.5 hours. From 23 to 51% of the target activity at the end of bombardment was measured in the final conjugate. Solid-liquid extraction purification of the astatinated intermediate, using Sep-pak columns (Waters), gave more reproducible yields in the final conjugation step. The 211At-labelled particles were incubated with fetal calf serum, human serum and human full blood at room temperature. The 211At activity on the particles was measured before and after three times washing at 4, 24 and 48 hours. The stability was not significantly different from 100% for all media and for all time points. This indicates that 211At-labelled particles can be stable under in vivo conditions, and may thereby be a promising agent for intracavitary radiotherapy on freefloating cancer cells or surface fixed cells.

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.

Objectives: Our purpose was to identify prognostic factors in stage I epithelial invasive ovarian carcinoma. Study Design: The traditional clinical and pathologic prognostic variables and deoxyribonucleic acid ploidy were analyzed in a group of 290 patients. Results: A multivariate analysis identified degree of differentiation as the most powerful prognostic indicator of disease-free survival, followed by deoxyribonucleic acid ploidy and, finally, International Federation of Gynecology and Obstetrics (1986) stage. Tumors with clear cell carcinoma elements were not graded, and in this subgroup International Federation of Gynecology and Obstetrics (1986) stage was the most important prognostic characteristic. When the effects of the three most important factors were accounted for in graded tumors, then none of the following were prognostic: histologic type, dense adhesion, extracapsular growth, ascites, rupture during surgery, International Federation of Gynecology and Obstetrics (1973) stage, size of tumor, and age and type of adjuvant treatment. None of 77 patients with well differentiated deoxyribonucleic acid diploid tumors had relapses. Conclusion: Deoxyribonucleic acid ploidy is an important new independent prognostic factor in stage I ovarian carcinoma.