Analysis and clinical correlation of infiltrating cytotoxic T cells in Hodgkin Lymphoma tumor samples using flow cytometry

Background: Progressive transformation of germinal centers (PTGC) is a disease of mostly young adults that generally presents as asymptomatic, localized or generalized lymphadenopathy. Although PTGC usually seen as nodal disease, it can occur at extranodal sites. In the differential diagnosis of chronic lymphadenopathies, infection, lymphoproliferative disorders and progressive transformation of germinal centers should be considered. The most significant entities in the differential diagnosis with PTGC are nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) and lymphocyte rich classical Hodgkin lymphoma. PTGC may precede, follow, or be concurrent with lymphomas. Objectives: To review the clinical and pathological features of PTGC, and PTGC’s relationship with lymphoid neoplasia in adult population. Material and Methods: The data of 33 patients who was diagnosed with PTCG at Hospital of Ege University School of Medicine, Pathology Department, between January 2000 and December 2014 were analyzed retrospectively. Clinical and Pathological Features: The median age of the patients was 43.8 years (26-66 years), and of 16 (48.5%) males and 17 (51.5%) females. Biopsy regions were; cervical lymph nodes (LN) 9 (27.3%), axillary LN 9 (27.3%), inguinal LN 6 (18.2%), submandibular LN 3 (9.1%), submental LN 2 (6.1%), parapancreatic LN 1 (3.0%), intraparotid LN 1 (3.0%), supraclavicular LN 1 (3.0%) and intramammarian LN 1 (3.0%). Recurrent PTGC was detected in only one (3.0%) patient. Diffuse large B cell lymphoma (DLBCL) and nodular lymphocyte predominant hodgkin lymphoma (NLPHL) was detected concurrent with PTGC in two cases. Also PTGC was detected 3 years after the diagnosis of DLBCL, NLPHL and T cell rich B cell lymphoma in 3 cases. There was no relapse in these 3 cases and no progression to lymphoma during follow-up of other patients. Conclusion: PTGC is not considered a premalignant condition but development of lymphoma have been reported rarely. If PTGC occurs in the follow of lymphoma cases, follow-ups may be intensified. NLPHL is the most important entity in differantial diagnosis of PTGC and patients should be carefully examined in terms of NLPHL.