OBJECTIVETo study the significance and differential diagnosis of intralymphatic accumulation of lymphocytes.

METHODSThe clinical and pathologic features of 4 cases of intralymphatic accumulation of lymphocytes were reviewed retrospectively. Immunohistochemical study was carried out and follow-up data were analyzed.

RESULTSThe sites of involvement included tonsil (2 cases), pharynx (1 case) and appendix (1 case). The duration of disease ranged from 1 week to 3 months. Follow up of the patients (from 3 to 84 months) showed no evidence of disease recurrence. Gross examination of the tissues (except in the case of appendiceal involvement) showed polypoid changes. Histologically, the lymphatic channels were filled up with small lymphocytes and associated with fibrosis in the vicinity. Immunohistochemical study revealed a T-cell phenotype of the intralymphatic lymphoid cells.

CONCLUSIONSThe accumulation of lymphocytes in lymphatic channels is associated with a benign clinical course. This phenomenon may be due to retention of lymphocytes secondary to the perilymphatic chronic inflammation and fibrosis. Although the lesion simulates intravascular lymphomatosis morphologically and shows a uniform T-cell phenotype, the lymphoid cells lack obvious cellular pleomorphism and mitotic activity. The solitary nature of the lesion, when coupled with the indolent clinical behavior, is also helpful in the differential diagnosis.