# Small intestinal NK/T-cell lymphoma with malignant peritoneal effusion as the first symptom: a case report and literature review

## TL;DR

A rare case of small intestinal NK/T-cell lymphoma presented with malignant peritoneal effusion, highlighting the disease's aggressive nature and diagnostic challenges.

## Contribution

This case report adds to the limited literature on small intestinal NK/T-cell lymphoma presenting with peritoneal effusion as the first symptom.

## Key findings

- Malignant peritoneal effusion was the initial symptom in a case of small intestinal NK/T-cell lymphoma.
- The patient had a poor prognosis despite aggressive treatment, emphasizing the disease's aggressiveness.
- Early detection and clinician awareness are critical for managing this rare lymphoma.

## Abstract

Small intestinal NK/T-cell lymphoma (NK/T-L) is a rare condition, and cases presenting with malignant peritoneal effusion as the initial symptoms are not well-documented. We report a unique case that contributes to the understanding of this rare disease.

A 47-year-old man was admitted to the hospital with a chief complaint of abdominal distension and weight loss persisting for over 2 months. Imaging studies revealed ascites and localized thickening of the small intestine. Paracentesis cytology revealed a significant presence of small-to-medium-sized lymphoid cells. Immunohistochemistry confirmed a diagnosis of T-cell lymphoma. Histological examination confirmed primary NK/T-L of the small intestine after PET-CT excluded metastases from other sites. Despite aggressive chemotherapy, the patient’s condition deteriorated, resulting in his death 4 months later.

This case highlights the importance of considering small intestinal NK/T-L in patients with abdominal symptoms and malignant peritoneal effusion. The aggressive nature and poor prognosis of this disease pose challenges in diagnosis and treatment. Increased awareness among clinicians and pathologists is crucial for early detection and improved patient outcomes.