Myeloma in Martinique; Characteristics and Overall Survival

Introduction

African Americans (AA) are twice as likely to be diagnosed with multiple myeloma (MM) as Caucasian Americans (CA). Differences in overall survival have also been shown between those two populations with no consistent explanation with regard to social status or genetic profile given by gene expression profiling. In Martinique, where most of the population has African or French Caribbean ethnic origin with similar increased incidence in MM, we lack data about disease characteristics and survival as compared to French Caucasian patients.

Material and methods

The aim of this single center retrospective study was to evaluate characteristics, progression free and overall survival of this population. We analyzed 54 MM elderly patients consecutively treated in Fort de France Hematology department from March 2007 to March 2012. All patients received first line treatment with melphalan 0.2 mg/kg/d, prednisone 2 mg/kg/d and thalidomide 400 mg/d every 6 weeks according to French IFM guidelines. Disease characteristics and survival data were analyzed and compared to French Caucasian elderly MM patients included in first line IFM published trials.

Results

Population had a median age of 80 years (66 to 93). Concerning prognostic markers, International Scoring System (ISS) was of 3 (high) in 52% of patients and cytogenetic analysis showed rearrangements with translocation 14q32 in 22% with 7% of t(4;14). When considering deletion 13q, it was found in 41% and deletion 17p in 6%. With a median follow up of 35 months, survival features showed median overall survival (OS) of 48.6 months and progression free survival (PFS) of 28.9 months.

Discussion

Compared to French Caucasian patients, our series showed that Martinique’s population was older and presented more aggressive disease based on ISS. Moreover, almost half patients presented with MDRD clearance lower than 60ml/min which conferred higher B2m and worse prognosis. We also confirmed results recently published by Weiss and all who described lower rate of IgH translocation in African American population with MM.

Despite higher median age and ISS, median overall survival of our population was unexpectedly similar to French published studies with IFM 99 06 trial showing median OS and PFS in MPT arm of 51.6 and 27.5 months respectively. In IFM 01/01 trial where patients were aged more than 75 with lower doses of melphalan and thalidomide, survival data showed median OS of 44 months and median PFS of 24.1 months. In meta analysis published by European Myeloma Network, median OS was even lower with 39.3 months.

Our data tend to show that French Caribbean patients with first line MM treated in Martinique appear to have similar overall survival as compared to French Caucasian patients despite higher median age and more adverse prognostic features which has not been reported so far. We plan to confirm those data with new analysis with longer median follow up and extensive clinical and biological disease characteristics evaluation.