A phase I/II study using a novel anti-mucin monoclonal antibody 2G3 labelled with 131I12 was conducted on 11 patients with chemo-resistant ascites, secondary to ovarian or breast cancer.54 The radioimmunotherapy was given by intraperitoneal injection and in three of the four patients who received the highest doses temporary palliation of their ascites lasting 6 weeks to death at 4 months was reported. This evidence concerns the gene MUC5AC and breast carcinoma.