Detailed clinicopathological characteristics and possible lymphomagenesis of type II intestinal enteropathy-associated T-cell lymphoma in Japan.

Twenty-six Japanese cases of type II enteropathy-associated T-cell lymphoma (EATL) were examined. Multiple tumors throughout the small intestine were found in 15 patients (58%) and duodenal and colonic mucosal lesions in 8 and 6 cases, respectively. Histologically, intramucosal tumor spread and a zone of neoplastic intraepithelial lymphocytes (IELs) neighboring the main transmural tumors were detected in 20 (91%) and 17 (77%) of the 22 cases examined, respectively. Inside and outside the IEL zone, some degree of enteropathy with many reactive small IELs and villous atrophy was detected in 11 cases (50%). Immunohistologically, many CD56/CD8-positive small IELs were found in the enteropathic lesions of 4 (36%) and 7 (64%) of these 11 cases. Lymphoma cells expressed tyrosine kinase receptor c-Met, serial phosphorylated (p)-mitogen-activated protein kinase/extracellular signal-regulated kinase, c-Myc, and Bcl2 in 18 (78%), 21 (91%), 11 (42%), and 19 (73%) of the total cases, respectively. By fluorescence in situ hybridization, chromosomal loci 7q31 (c-Met) and 8q24 (c-Myc) were amplified in 11 (65%) and 12 (71%) of the 17 cases analyzed. Gain of 7q31 and c-Met expression were significantly (P < .01) higher than in peripheral CD8-positive T-cell or CD56-positive natural killer-cell lymphomas. Enteropathy was seen near the IEL zone in type II EATL, and activation of the c-Met, mitogen-activated protein kinase/extracellular signal-regulated kinase-mitogen-activated protein kinase pathway, and c-Myc-Bcl2-mediated cell survival may play important roles in lymphomagenesis, converting enteropathy to type II EATL. Seven cases in the early clinical stages I and II-1 showed significantly (P < .01) better prognoses than did those in the advanced stages. Early detection of the mucosal lesions and tumors may improve patient prognosis.

[The application of fluorescence in situ hybridization to the peripheral-blood preparations].

The hematologic malignancy with specific chromosomal/genetic abnormality is separately classified by the WHO classification of tumors hematopoietic and lymphoid tissues. The chromosomal abnormalities, t (9; 22), t (8; 21), t (15; 17) and inv (16) are especially important for the establishment of therapeutic strategy and prognostication. We examined in this study, five cases were analyzed, because abnormal cells were recognized by the differential white blood count of the peripheral-blood and specific chromosomal abnormalities were suspected. Whether peripheral-blood preparations after May-Grünwald Giemsa staining could be used for fluorescence in situ hybridization (FISH). The fusion signals were detected in the high rate by using a peripheral-blood specimen in four cases, except for one case that had no specific chromosomal abnormality.