[Population-based incidence of lymphoid neoplasms by histological subtypes in Girona (Spain), 1994-2001]

We aimed to assess the distribution of the lymphoid neoplasms and their histological subtypes in accordance with the World Health Organization (WHO) classification by calculating their incidences rates in our area.

From January 1994 to December 2001, 1,288 patients diagnosed with lymphoid neoplasms were recruited in the population-based Cancer Registry of Girona. Former pathological and hematological diagnoses were reviewed and some were prospectively reclassified following the latest WHO classification.

Following criteria established by WHO classification the distribution of lymphoid neoplasms was as follows: 77.3% B-cell neoplasm, 5.9% T-cell neoplasm, 8.7% Hodgkin lymphoma and 8,2% was unclassifiable. From 1994 TO 2001 the lymphoid neoplasm crude incidence rates was 35.8 per 100,000 men-year, while it was 25.7 new cases per 100,000 women-year. In children (< 15 years old), precursor B-lymphoblastic lymphoma/leukemia (65%) and Hodgkin lymphoma (20%) were the most frequent lymphoid neoplasm, whereas myeloma (17.8%), diffuse large B-cell lymphoma (13.5%) showed the highest incidence rate in adults.

A higher incidence rate of lymphoid neoplasms was found in men in our area compared with other geographical areas in Spain, which could suggested a faster approximation to the pattern observed in industrialized societies. The cause of this geographical distribution is unknown.