Primary small intestinal extranodal NK/T cell lymphoma, nasal type with kidney involvement: a rare case report and literature review

BACKGROUND: Extranodal NK/T cell lymphoma, nasal type (EN-NK/T-NT) is a rare and aggressive type of non-Hodgkin’s lymphoma. EN-NK/T-NT seldom occurs in the gastrointestinal tract, and renal involvement is relatively rare. CASE PRESENTATION: Here we report a case of primary small intestinal EN-NK/T-NT with kidney involvement. We present the case of a 71-year-old female who was admitted to our hospital for coronary heart disease with a fever of unknown origin. Laboratory examination showed renal impairment and PET/CT showed a locally thickened wall of the small intestine, abnormally increased FDG metabolism in the right lower abdomen, and multiple slightly high-density masses with abnormal increased FDG metabolism in the right kidney. The gross specimen showed a grayish-white lump located in the ileum approximately 15 cm away from the ileocecum, and two grayish-white lumps located in the upper and lower poles of the right kidney, respectively. The pathological diagnosis was EN-NK/T-NT. The patient died approximately 10 months after the operation. CONCLUSION: EN-NK/T-NT is a rare type of non-Hodgkin’s lymphoma and may develop insidiously, with fever as the only clinical manifestation. The disease was found to be difficult to diagnose in the early stage, resulting in a highly aggressive clinical course and short survival time.