Population-Based Incidence and Mortality Rates of Hematologic Malignancies regarding the Adult Population of Crete, Greece, and Analyses of Their Time Trends and Their Geographical Dis-Tribution: A First Approach from the Cancer Registry of Crete (CRC) for a 22-Year Time Period (1992–2013)

Population-based data on hematologic malignancies (HM) are rare in Greece regarding adults (≥18 years old). The aim of this study was the assessment of the burden of these malignant neoplasms (MN) for adults in Crete. The study assessed temporal trends of incidence and mortality, depicted their spatial distribution and extracted net-survival curves of patients. Population-data on these MN were obtained from the database of the Cancer Registry of Crete, for a 22 year time period (1/1/1992-31/12/2013). All HM were classified into four main groups of diseases: (1) Hodgkin’s lymphoma (HL); (2) Non-Hodgkin’s lymphomas (NHLs); (3) Multiple myeloma (MM); and (4) All chronic and acute leukemias. Annual, gender-specific, age standardized incidence and mortality rates were estimated (ASIR/100.000/year; ASMR/100.000/year). A total of 3,380 newly diagnosed cases were included in the final analyses; All ASIRs/100,000 increased significantly throughout the study period presenting differences in their geographical distribution of rates among municipalities of Crete. ASIRs for NHLs, HL, MM, leukemias and for all 4 MN were 13.1, 2.6, 4.7, 11.7 and 32.1, respectively, in 2013. Five-year net-survival for patients diagnosed with NHLs, HL, MM and leukemias were: 82%, 85%, 52% and 56%, respectively. This first research article studying a long period of time for adults in Greece generates hypotheses on the existence of risk factors that may partly explain this variation of rates.