Distribution of lymphoid neoplasms in Northeast Turkey: A retrospective analysis of 1136 cases according to the World Health Organization classification

Objective: Malignant lymphoma is one of the most common cancer type around the world. In this study, the distribution and demographic characteristics of the histologic subgroups of mature lymphoid neoplasms in Northeast Turkey were investigated. Methods: The study consists of 1136 patients diagnosed as mature lymphoid neoplasm between 2008 and 2014. The demographic data of the patients were analysed and histological subgrouping was performed according to the World Health Organization classification. Results: Mature B-cell neoplasms accounted for 79.2% (n=900) of all lymphoid neoplasms, Hodgkin lymphoma (HL) for 10.9% (n=124), mature T/natural killer-cell neoplasms for 9% (n=102), and histiocytic and dendritic cell neoplasms for 0.9% (n=10). In our study, the most common subtypes of lymphoid neoplasms were as follows: diffuse large B-cell lymphoma (n=261; 23%), plasma cell myeloma (n=252; 22.2%), chronic lymphocytic leukemia/small lymphocytic lymphoma (n=230; 20.2%), mycosis fungoides (MF) (n=66; 5.8%) and nodular sclerosing type classical HL (n=63; 5.5%). Only 2.9% of the cases of non-Hodgkin lymphoma (NHL) were follicular lymphoma. All patients with HL were diagnosed by a lymph node biopsy. However, 48.1% of the patients with NHL arose from extranodal sites. Conclusion: This is the first study investigating the distribution of lymphoid neoplasms in Northeast Anatolia region with the review of the literature. The present study showed that the epidemiologic features similar to those reported in Western and Asian countries, whereas some subtypes showed distinct features. The high frequency of MF and the low frequency of follicular lymphoma are interesting findings of this study.