Long-term remission of primary gastric T cell lymphoma associated with human T lymphotropic virus type 1: a report of two cases and review of the literature

Endoscopic and clinicopathological characteristics of gastrointestinal adult T-cell leukemia/lymphoma

Background

Adult T-cell leukemia/lymphoma (ATLL) frequently involves the gastrointestinal (GI) tract, and patients mainly show an aggressive clinical course despite of intensive cytotoxic treatments. We investigated the characteristic clinicopathological and endoscopic features of GI ATLL.

Methods

This was a retrospective analysis of 61 GI tract lesions in 54 ATLL patients.

Results

Thirty-six (67%) patients were classified as having lymphoma-type ATLL and 18 (33%) patients were classified as having acute-type with leukemic changes. Examined ATLL lesions in the stomach and intestine (small intestine and colorectum) were 40 (66%) and 21 (34%), respectively. Gastric ATLL lesions were frequently found in the lymphoma-type (29/38; 76%) compared with the acute-type lesions (11/23; 48%; P=0.023). Intestinal ATLL lesions were frequent in the acute-type (12/23; 52%) compared with the lymphoma-type lesions (9/38; 24%; P=0.023). Endoscopically, tumor-forming type lesions were significantly more frequent in lymphoma-type ATLL lesions (29/38 lesions; 76%) compared with acute-type lesions (10/23; 44%; P=0.0096). The superficial spreading-type was significantly more frequent in acute-type lesions (12/23 lesions; 52%) compared with lymphoma-type lesions (3/38; 8%; P=0.0003). Additionally, gastropathy-, enteropathy-, or proctocolitis-like lesions were distinct features, mainly in the acute type (9/23 lesions; 39%). Twenty three of 39 tumor-forming-type lesions (59%) were significantly composed of pleomorphic or anaplastic large cell lymphoma, and 13 of 15 superficial spreading-type lesions (87%) were significantly composed of pleomorphic medium-sized cells (P=0.007, in each). Six patients (11%) who were estimated as having primary GI ATLL based on restricted clinical stages, showed a significantly better overall survival (OS) compared with the 48 advanced-stage patients (P=0.017). Twenty patients with solitary tumor-forming-type lesions showed a significantly better OS than 17 patients with the multiple tumor-forming-type (P=0.015) and five with the mucosal-thickening-type lesions (P=0.04). Twenty-six patients with pleomorphic or anaplastic large cell ATLL showed a significantly better prognosis compared with 28 patients with pleomorphic medium-sized ATLL (P=0.034).

Conclusions

ATLL predominantly involves the stomach. Leukemic behavior of ATLL had a large influence on the tumor location and endoscopic features of GI tract lesions. Gastropathy-, enteropathy-, and proctocolitis-like lesions showed additional distinct characteristics. Primary GI ATLL in the early clinical stages, solitary tumor-forming-type lesions and large tumor cells showed better prognostic factors than other factors, respectively.

Primary gastric T cell lymphoma mimicking marginal zone B cell lymphoma of mucosa-associated lymphoid tissue

Primary gastric T cell lymphoma is rare and mostly of large cell type. In this paper, we present a case of gastric T cell lymphoma morphologically similar to the gastric marginal zone B cell lymphoma of mucosa-associated lymphoid tissue (MALT). Morphologically, the cells are small with abundant clear cytoplasm. Lymphoepithelial lesions are readily identified with diffuse destruction of gastric glands. Immunohistochemically, the neoplastic cells are CD3+/CD4+/CD8−/Granzyme B−. Molecular studies revealed monoclonal T cell receptor γ gene rearrangement. Clinically, the patient responded initially to four cycles of R-CHOP, but then progressed. Because peripheral T cell lymphoma is usually associated with a poor prognosis, whereas marginal zone B cell lymphoma is an indolent lymphoproliferative disorder, this morphologic mimicry should be recognized and completely investigated when atypical small lymphoid infiltrates with lymphoepithelial lesions are encountered in the stomach.