A retrospective multicenter study on thalidomide treatment in relapsed/refractory multiple myeloma

We report the results about thalidomide therapy in 40 advanced multiple myeloma (MM) patients. The treatment plan consisted in thalidomide at escalating dosage from 100 mg/day to 800 mg/day until the best response and then thalidomide was tapered until a maintenance dosage. Among 40 patients, 18 had been treated with at least 1 chemotherapy (CT) regimen, 17 with 2 or more CT lines, 3 patients had received high dose CT followed by autologous stem cell transplantation (ASCT); 2 patients presented a plasma cell leukaemia previously treated by standard CT. Eighteen patients (47%) obtained a response: out of which 2 had a complete response (CR), 6 a major response, 6 partial response and 4 a minor response. No patients reached maximum dosage because of side effects. The majority received low thalidomide dosages (100-200 mg/d). Predominant side effects were neurological: somnolence, sensitive neuropathies, constipation; 2 patients experienced a deep venous thrombosis. To date, 25 (62.5%) patients are alive; among the 18 responders, 13 are in continuous response, 3 relapsed and 2 died in disease remission. Statistical significative differences of survival were observed between responder and non-responder patients (75% vs. 18% at 2 years, p=0.024) and between patients treated in late (> 12 months) or early (<12 months) relapse (86% vs. 22% at 2 years, p=0.014).