Incidence, Clinical Characteristics and Survival of Malignant Lymphomas in the Province of Modena (Italy); a Population-Based Study.

Abstract

The incidence of lymphomas has increased in many parts of the world in recent decades. We conducted a population-based study of peripheral lymphoma (PL) in the province of Modena (Italy). According to the international classification for lymphomas (WHO/ICD-O-3) we evaluated incidence patterns and time trends of 1,582 cases of PLs diagnosed between 1997–2003, also providing details of clinical characteristics, treatment and outcome of different entities. World Age Standardized Rates (ASR) varied substantially among lymphoid neoplasm subtypes. Overall, ASR (per 100,000) was 13.4 for B-cell lymphomas (16.5 and 10.6 for males and females respectively), 2.2 for T-cell lymphomas (3.1 and 1.5) and 3.4 for Hodgkin lymphoma. Among B-NHL the highest ASR was observed for Diffuse large B-cell lymphoma (DLBCL, 4.8) and Small lymphocytic lymphoma (CLL/SLL, 3.3). Among T-cell lymphomas, ASR was 1.4 for Mycosis fungoides/Sezary syndrome (MF/SS) and 0.4 for both Peripheral T-cell lymphoma (PTCL) and Anaplastic large cell lymphoma (ALCL). The overall annual percent change (APC) of the World ASR was 1.62 (C.I.95%: −4.32; 7.93). Extranodal (EN) involvement was observed in 49% of cases; a diagnosis of Primary EN lymphoma (PENL) was confirmed in 27.8% of cases. In addition to MF/SS, the most frequently reported PENL were marginal zone lymphomas (MZL) and DLBCL. The documented five years Overall Survival (OS) for the whole series was 61.9%, being 61.7%, 55.3% and 83% for B-NHL, T-NHL and HL, respectively. These data confirm an overall improvement when compared with available historical controls for the main European countries. In addition, using period analysis we could estimate more up-to-date survival data within our studied series (all patients vs those diagnosed after 2002): survival of patients with MZL, DLBCL and HL strongly improved during the study period. Among different lymphoma subtypes, patients with Hairy cell leukemia (HCL), HL and MF/SS had the best survival with 5-year OS of 94%, 83% and 82%, respectively. In particular, for HCL and MF/SS the analysis of the Relative Survival suggested that there was no substantial difference in survival compared with healthy population. Our study provides a comprehensive description of both epidemiological and clinical features of PL in the province of Modena, recognizing in a population-based approach, major advances in the curability of some histological subtypes.