CD8-positive indolent T-Cell lymphoproliferative disorder of the gastrointestinal tract: A case report and review of literature

Primary cutaneous lymphoproliferations in the gray zone between marginal zone lymphoma and CD4+ small/medium T-cell lymphoproliferative disease

BACKGROUND

Primary cutaneous marginal zone lymphoma (PCMZL) and primary cutaneous CD4+ small/medium T-cell lymphoproliferative disease (CD4+ TLPD) are two distinct entities with excellent prognosis; however, they show profound clinical and histopathological similarities, leading to differential diagnostic uncertainty.

AIMS

Our aim was to review and reanalyze cases of primary cutaneous lymphoproliferations diagnosed at Semmelweis University, featuring characteristics of PCMZL and CD4+ TLPD.

MATERIALS AND METHODS

Cutaneous lymphoma biopsy specimens between 2018 and 2022 were collected and re-evaluated. Medical history, clinical picture, imaging, and laboratory findings were collected. Immunohistochemical staining for CD20, CD3, BCL6, CD10, PD1, CD3, CD4, CD8, and PCR tests for IGH, IGK, TCRB, and TCRG were repeated in selected cases.

RESULTS

Among 55 cases diagnosed as PCMZL (16) or CD4+ TLPD (39), 3 patients had been diagnosed with both LPDs at different time points of their disease course. Four additional patients were identified with single lesions featuring overlapping histopathological characteristics of both LPDs and both monoclonal IGH and TCR rearrangements. All patients are currently in complete remission with local treatment.

CONCLUSION

We propose that besides the overlapping histopathological, molecular, and clinical features, the subsequent appearance of PCMZL and CD4+ TLPD in a short timeframe in the same patients may suggest a common pathogenic background.

Indolent T-cell lymphoproliferative disorder of gastrointestinal tract with unusual clinical courses: report of 6 cases and literature review

Indolent T-cell lymphoproliferative disorder of the gastrointestinal tract (iTLPD-GI) is a rare neoplasm usually having an indolent clinical course and easily misdiagnosed as inflammatory bowel disease or other T-cell lymphomas. A subset of the disorders that progressed to overt peripheral T-cell lymphoma have been reported, and the etiology and pathogenesis are poorly understood. The current study retrospectively examined the pathological, molecular, and clinical features of 6 cases of iTLPD-GI. Hematoxylin and eosin staining, immunohistochemistry, in situ hybridization, T-cell receptor gene rearrangement, and next-generation sequencing (NGS) were performed with the diseased tissues. All the 6 patients were immunocompetent Chinese men, who presented with recurrent abdominal pain and diarrhea for 4 to 13 years. Histologically, the intestinal tissue was expanded by lymphoid infiltration, composed of small-to-medium-sized lymphocytes with gland intact. The neoplastic cells were CD4 - /CD8 + with expression of TIA1 and variable granzyme B in five cases, and the other one was CD4 + /CD8 - . Two of the 5 patients progressed to more aggressive T-cell lymphoma and died of disease with complications. NGS identified TET2 and DDX3X mutations in patient 1, and BIRC6 and REV3L mutations in patient 2. Literature review indicated that iTLPD-GI with CD4 - /CD8 + immunophenotype was more commonly reported in Chinese cases. Our limited data indicated CD4-/CD8 + iTLPD-GI have similar potential to progress to more aggressive T-cell lymphoma as that of CD4 + /CD8 - , and gradually increased expression of granzyme B and Ki-67 may be early signs of the disease progression. Gain of novel gene mutations may be indicators of the pathogenesis.