Immunoscintigraphy of ovarian carcinoma using OC 125 monoclonal antibody

Immunoscintigraphy (ISG) with I-131 labeled OC 125 F (ab')2 fragments was studied in 7 patients for primary diagnosis and follow up of ovarian cancer. Total body planar photoscans with a scintillation camera were performed three to seven days after antibody application and results were compared with operation and/or computed tomography (CT) examination. By the region of interest technique, the tumor to background ratio was calaulated in vivo. Results are as follows. 1) The sensitivity of ISG and CT for detection of 14 tumor sites which were confirmed with histopathology were 100 % and 57.1 % and the sensitivity for the detection of omental metastasis were 100 % and 20 % respectively. 2) There were no correlation between the serum CA 125 levels and tumor to background antibody uptake ratio. 3) Tumor to background antibody uptake ratio were progressively increased from day 3 to day 7. (author)