Radioimmunoconjugates for the treatment of cancer.

Radioimmunotherapy (RIT) has been developed for more than 30 years. Two products targeting the CD20 antigen are approved in the treatment of non-Hodgkin B-cell lymphoma (NHBL): iodine 131-tositumomab and yttrium 90-ibritumomab tiuxetan. RIT can be integrated in clinical practice for the treatment of patients with relapsed or refractory follicular lymphoma (FL) or as consolidation after induction chemotherapy. High-dose treatment, RIT in first-line treatment, fractionated RIT, and use of new humanized monoclonal antibodies (MAbs), in particular targeting CD22, showed promising results in NHBL. In other hemopathies, such as multiple myeloma, efficacy has been demonstrated in preclinical studies. In solid tumors, more resistant to radiation and less accessible to large molecules such as MAbs, clinical efficacy remains limited. However, pretargeting methods have shown clinical efficacy. Finally, new beta emitters such as lutetium 177, with better physical properties will further improve the safety of RIT and alpha emitters, such as bismuth 213 or astatine 211, offer the theoretical possibility to eradicate the last microscopic clusters of tumor cells, in the consolidation setting. Personalized treatments, based on quantitative positron emission tomography (PET), pre-therapeutic imaging, and dosimetry procedures, also could be applied to adapt injected activity to each patient.

Intra-arterial injection of 131I-labeled Lipiodol for advanced hepatocellular carcinoma: a 7 years' experience.

BACKGROUND: Internal irradiation with iodine-131 (I)-labeled Lipiodol is one of the currently available forms of palliative therapy for patients with advanced hepatocellular carcinoma (HCC). Despite a cumulative experience of more than 10 years with this treatment, only a few studies have reported on its efficacy and safety. OBJECTIVE: The aim of this study was to retrospectively evaluate the efficacy of intra-arterial I-labeled Lipiodol injection for treatment against advanced HCC. MATERIALS AND METHODS: Fifty patients (47 men and three women; mean age 64 years) given an intra-arterial injection of I-Lipiodol (5 ml of 2.2 GBq Lipiodol labeled with I; number of mean sessions per patient, 1.3; range 1-4) were retrospectively compared with 36 patients (31 men and five women; mean age 64 years) who were given only medical support. Portal vein thrombosis was present in 86 and 100% of patients, respectively. Efficacy was determined on the basis of overall survival as the endpoint using the Kaplan-Meier method. Tumor response was evaluated with computed tomography according to Response Evaluation Criteria In Solid Tumors (RECIST 1.1) and European Association for the Study of the Liver (EASL) criteria. RESULTS: For patients treated with I-Lipiodol, median survival was 32 weeks, compared with 8 weeks for the untreated group (P=0.007). Survival at 6 months and at 1 and 2 years was 65, 35, and 22%, respectively, for patients treated with I-Lipiodol compared with 28, 8, and 0% for the untreated group. At 1 month, more than 80% of patients were responders (complete response, partial response, and stable disease) on the basis of the RECIST and EASL criteria, and at 6 months 39% were responders. No radiotoxic effect was observed, especially with respect to interstitial pneumonia. No significant difference was observed between survival and α-fetoprotein levels, Barcelona Clinic Liver Cancer clinical score, and portal vein thrombosis. CONCLUSION: Intra-arterial injection of I-Lipiodol is safe and provides significant survival benefit in terms of overall survival for patients with advanced HCC.