Diagnostic and intraoperative immunoscintigraphy in ovarian cancer

A new strategy for tumor detection using immunoscintigraphic techniques was used in an attempt to improve the diagnostic potential of conventional external immunoscintigraphy. Twelve patients who were strongly suspected to either suffer from primary or recurrent ovarian cancer were investigated as follows: radioimmuno-scintigraphy (RIS) by means of radiolabelled antibodies was performed in all patients prior to operation (first or second look). During the operative procedure, which always took place immediately after completion of the diagnostic RIS, a hand-held gamma-ray detection probe, especially developed for this purpose was used for the purpose of identifying radiolabelled tumor sites intra-operatively in the open abdomen. In 10 out of 12 of the investigated patients, Radioisotope-Assisted Surgery (RAS) could be performed successfully. The count rates in cancer sites ranged from 150-250 cts per 6 s vs. 30-50 cts per 6 s in normal tissues. While the presence of malignant-tumor sites could always be predicted by conventional RIS, RAS failed twice, but revealed more accurate information concerning the real extent of the disease.