Clinical and pathological analysis of gastrointestinal inert T cell lymphoid tissue proliferative diseases

Dan Yuan¹Na Liang²Dong-Yue Wang³Jin-Jing Wang¹Cong-Wei Jia^4*

• ¹Department of Pathology, Affiliated hospital of Zunyi Medical University, Zunyi, China
• ²Department of Histology and Embryology, School of Basic Medicine, Zunyi Medical University, Zunyi, China, Zunyi, China
• ³Department of Pathology, Jilin People's Hospital, Jilin, China, Jilin, China
• ⁴Department of Pathology, Peking Union Medical College Hospital (CAMS), Beijing, Beijing, China

Objective: To investigate the clinicopathological features of indolent T-cell lymphoproliferative disease of the gastrointestinal tract (ITLPD-GI) and improve its diagnostic and therapeutic approaches. Methods: A retrospective analysis was conducted on 8 ITLPD-GI patients treated between January 2018 and January 2024. Clinical data, pathological features, immunophenotypes, molecular testing results, and follow-up records were reviewed. Results:Clinical characteristics: Male-to-female ratio 3:5, mean age at onset 42 years.Symptoms: Predominantly diarrhea and abdominal pain.Endoscopic findings: Erosions, multiple shallow ulcers, and small polypoid lesions.Pathological features:Histology: Atrophy of gastric/intestinal glands with diffuse infiltration of small lymphocytes (round/irregular nuclei, dense chromatin) in the lamina propria; rare mitoses; absence of angioinvasion or necrosis. Notably, 2 cases showed prominent plasma cell infiltration in the superficial mucosa.Immunophenotype: Pan-T-cell markers positive (5/8); CD4-/CD8+ (5/8), CD4+/CD8+ (2/8), CD4+/CD8-(1/8); aberrant CD20 expression (2/8); low Ki-67 index.TCR rearrangement: Monoclonal in all 4 tested cases.Treatment and prognosis:Supportive therapy (5 cases): Dietary modification, immunosuppression, immunomodulation, and anti-infective agents. Symptoms resolved in 1 case but persisted in 4.Targeted therapy (1 CD20+ case): Rituximab added, with no improvement after 14-month follow-up.Chemotherapy (2 cases): Prednisone + thalidomide; 1 achieved significant remission at 9 months, while the other showed no response (persistent diarrhea/anxiety) at 35 months.No disease progression was observed during follow-up. Conclusion: ITLPD-GI is a rare indolent monoclonal T-cell proliferation with nonspecific clinical/endoscopic features, necessitating differentiation from aggressive lymphomas to avoid misdiagnosis and overtreatment. Diagnosis relies on histomorphology, immunohistochemistry, and TCR clonality assessment (critical for atypical cases, e.g., CD20+). Most patients have favorable outcomes with conservative management. Enhanced clinical awareness and novel therapeutic targets warrant further exploration.