Phase II trial of repeated carcinoembryonic antigen (CEA) radioimmunotherapy (RAIT) with 131I-Labetuzumab post salvage resection of colorectal metastases in the liver

13572 Background: Complete resection of liver metastases (LM) remains the treatment of choice for colorectal cancer (CRC). As shown recently (Liersch et al., JCO 2005; 23:6763–70), RAIT with a single application of the humanized monoclonal anti-CEA antibody, 131I-labetuzumab, improved both the median overall survival (OS) and 5-yr survival rates significantly in patients post salvage resection of LM. The major adverse side effects (≤ grade 3 CTC) were transient myelosuppression and/or thrombocytopenia in patients receiving 40 to 60 mCi/m2 of 131I-labetuzumab. These encouraging results stimulated the current ongoing Phase-II trial to evaluate the safety of repeated RAIT at doses of 2 × 50 mCi/m2 (3 mos apart), post salvage resection of LM. Methods: At present, 13 patients (primary CRC: 8x UICC stage IV, 1× UICC stage III and 4× UICC stage II) who underwent surgery for LM of CRC (postsalvage mTMN stages: 4× mT4, 2× mT3, 6× mT2, 1× mT1) have received the first dose of 50 mCi/m2 131I-labetuzumab within 2 mos ...