Lymphoid neoplasms in Bulgaria according to the WHO classification (2001). The experience of the National Center of Haematology.

The aim of the present study was to assess the incidence of lymphoma subtypes in the largest cohort of patients in Bulgaria, referred to the National Center of Haematology and Transfusiology between 01.01.2003 and 31.12.2004, applying the WHO classification criteria, including precursor and mature cell neoplasias, plasmacytoma and Hodgkin lymphomas. A total of 790 cases were newly diagnosed. Hodgkin lymphomas comprised 24.6% of the cases, B-cell neoplasias - 66.5% whereas T/NK-cell neoplasias - 6.9% of the total. Specimens were inadequate for subclassification in 2.2% of the cases. Detailed data on the subtypes are presented and compared to reported data from other geographic locations.