Clinical Features and Outcomes of Patients with Double-Hit/Triple-Hit Multiple Myeloma Detected at Relapse.

Introduction: mSMART classifies high-risk Multiple Myeloma patients into Double Hit and Triple Hit Myeloma (DH/THM) on the basis of the number of high-risk cytogenetic abnormalities detected. We aimed to study the clinical profile and outcomes of patients with DH/THM detected at relapse in a real-world setting. Methods: The case records of all relapsed multiple myeloma patients with DH/THM diagnosed between January 2018 and December 2020 were identified and information regarding baseline characteristics, therapy and outcomes was noted. Results: Seventeen patients were diagnosed with DH/THM at relapse during the study period. Twelve patients (70.6%) were in first relapse, while 3 patients were diagnosed at second relapse and 1 patient each at 3rd and 5th relapse respectively. The most common cytogenetic combination was IgH-FGFR3 translocation with gain of 1q (seen in 10 patients; 58.8%). Ten patients (58.8%) died within the first 2 months of diagnosis and 16 patients (94.1%) died during follow up (range 0-16 months). The most common cause of death was progressive/active disease (9 patients, 56.3%). Discussion: The outcome of DH/THM at relapse is associated with an aggressive presentation and poor outcomes in the real-world setting. These patients are candidates for early aggressive or novel therapy or clinical trials.