부산대학교 도서관

Histological transformation is a well-known event in patients with follicular lymphoma (FL) and chronic lymphocytic leukemia (CLL) conferring an unfavorable prognosis. The concept of "accelerated" CLL is frequently used by both pathologists and clinicians. However, neither histological criteria to define this form of CLL nor its clinical correlates and prognostic impact have been formally defined in large series of patients.The aim of the first study was to analyze incidence and risk factors for histological transformation in a large series of FL patients. The aim of the second study was to evaluate the impact on survival of histological characteristics (proliferation) in CLL and to define the histological form of "accelerated" CLL according to these findings.Two-hundred and seventy-six patients diagnosed in a single institution were studied and main clinic and biological variables were assessed for histological transformation and survival. FLIPI and histology were the most important variables predicting histological transformation in FL. Tissue biopsies from 100 patients with CLL were analyzed for the size of proliferation centers (PCs) and their proliferation rate as assessed by mitosis count and Ki-67 immunostaining. Histological patterns were correlated with main clinico-biological features and outcome. The presence of expanded PCs and/or highly active PCs identifies a group of patients with "accelerated" CLL characterized by an aggressive clinical behaviour.