Role of immunoglobulin G fragment C receptor polymorphism-mediated antibody-dependant cellular cytotoxicity in colorectal cancer treated with cetuximab therapy.

Antibody-dependent cellular cytotoxicity (ADCC), which is activated by effector cells via immunoglobulin G (IgG) fragment C receptors (FcRs), was proposed as a mechanism of cetuximab efficacy. Peripheral blood mononuclear cells (PBMCs) from 23 healthy donors and 13 patients with metastatic colorectal cancer (mCRC) treated with cetuximab were tested for FcγR polymorphisms and cetuximab-mediated ADCC. ADCC was measured by chromium-51 release on a epidermal growth factor receptor (EGFR)-positive human colon cancer cell line. Overall, 86 mCRC patients were genotyped for study purposes. PBMCs harbouring the FcγRIIIa 158 V/V genotype had a significantly higher cetuximab-mediated ADCC. No correlation was found between FcγR polymorphisms and response rate or time to progression after cetuximab-based therapy. Despite the in vitro analysis showing that the FcγRIIIa 158 V/V genotype is associated with higher ADCC, clinical data do not support a predictive role of FcγRIIIa polymorphisms in mCRC treated with cetuximab.

Primary cardiac Burkett's type lymphoma: transthoracic echocardiography, multidetector computed tomography and magnetic resonance findings.

Although primary cardiac lymphoma is an extremely rare disease and is associated with high mortality, it is treatable when diagnosed appropriately. We describe the transthoracic echocardiography, 16-row multidetector computed tomography (16-MDCT) and magnetic resonance findings of primary cardiac lymphoma in an immunocompromised patient and review of the literature.