An electronmicroscopic cytomorphometric analysis of 55 cases of T-cell lymphomas.

Abstract

Lymphoma cells in 55 cases of T-cell lymphomas (T-ML) were analyzed by cytomorphometry on electronmicrographs in order to evaluate the criteria of peripheral T-cell malignant lymphomas (PTML) proposed by Lennert and Suchi et al. and to see the cytomorphological features of adult T-cell leukemia/lymphomas (ATLL). Nuclear area, nuclear contour index (NCI), nucleocytoplasmic ratio (N/C) and the relationship between the thickness of perinuclear heterochromatin (PNHC) and nuclear area were employed as factors of this cytomorphometry. The relationship between PNHC and nuclear area was evaluated as continuous or dispersed by means of statistical comparison of nuclear area among 4 kinds of lymphoma cells showing the PNHC's thickness graded in 4. When T-MLs were categorized in 3 groups by cell size, the factors characterized subtypes according to the criteria of PTML and showed peculiar features of ATLL even in pleomorphic lymphoma (PLEO). In the small or medium-sized cell T-MLs, T-cell lymphoblastic type (1 case) and T-zone lymphoma (I case) were differentiated by N/C, PLEO medium-sized cell type (PLED-M) of ATLL (12 cases) indicated larger nuclear area and higher NCI and showed the continuous relationship of PNHC, PLEO-M of european case (EPTL, 4 cases) and angioimmunoblastic lymphoadenopathy with dysproteinemia (AILD)-type PTML (2 cases) indicated similar cytomorphometric features, and T-cell chronic lymphocytic leukemia (1 case) revealed low value of NCI. In the medium-sized and large cell T-MLs, the contrareiety in the relationship of PNHC differentiated ATLL (continuous, 14 cases) from that of EPTL (dispersed, 2 cases). In the large cell T-MLs, PLEO large cell type (PLED-L) of EPTL (2 cases) indicated smaller nuclear area and PLEO-L of ATLL (3 cases) revealed larger nuclear area than T-cell immunoblastic type (2 cases). Mycosis fungoides (MF) in the lymph node (2 cases) revealed higher values of NCI and N/C. Furthermore, the cytomorphometric factors differentiated ATLL (4 cases) and MF (5 cases) in the skin, indicating much higher values of NCI in MF than ATLL in the skin.