Mucosal intralymphatic spread in a relapsed diffuse large B cell lymphoma

Intralymphatic spread is a rare finding and is associated with poor prognosis in diffuse large B cell lymphoma (DLBCL). Here, we report a case of relapsed DLBCL with mucosal intralymphatic spread. A 69-year-old man had been diagnosed with gastric DLBCL stage IIE at 57 years. He had a relapse with generalized lymphadenopathy and extranodal involvement at 61 years; then, second complete remission was achieved after salvage chemotherapy. He then had a second relapse with involvement of the terminal ileum, spinal cord, and left tonsil. The terminal ileum showed intralymphatic spread in the lamina propria of the intestinal villi, which was confirmed by D2–40 immunostaining. Eleven months later, another biopsy showed prominent intralymphatic spread in the mucosa of the terminal ileum. After salvage therapies, the spinal cord and tonsillar tumors resolved, but the intestinal tumors were refractory. The patient eventually died of progressive disease. In contrast to previously reported cases, the involved lymphatic vessels were observed in the mucosa, and the lymphoma cells expressed CD5 in the first colonoscopic biopsy. This rare case broadens the spectrum of intralymphatic spread in DLBCL.