Miliarial‐type perifollicular B‐cell pseudolymphoma (lymphocytoma cutis): a misleading eruption in two women

Abstract

Disseminated miliarial-type lymphocytoma cutis is a rare clinicopathologic subtype of lymphocytoma, characterized by numerous translucent micropapules and located on the head and neck. We describe here the clinical, histological and immunological features of miliarial-type perifollicular B-cell pseudolymphoma in two women aged 32 and 49 years presenting with numerous 1-2 mm translucent papules on the head and neck. Microscopic examination revealed features typical of a miniature lymphocytoma cutis with a superficial nodular infiltrate housing small well-circumscribed germinal centers containing tingible body macrophages and surrounded by a distinct mantle zone. The immunohistological profile was also typical of lymphocytoma cutis, and polymerase chain reaction analysis of the IgH gene rearrangement did not show any clonal B-cell population. The lesions resolved spontaneously in one case and improved after treatment with hydroxychloroquine in the second patient. The presentation of this subtype of lymphocytoma is a formidable clinical diagnostic challenge. Rosacea, sarcoidosis, democidiosis, lupus miliaris disseminatus faciei and steroid acne are easy to exclude on the basis of histological profile. However, the miliarial form of primary cutaneous center lymphoma is difficult to rule out. Dermatologists and dermatopathologists should be aware of this unusual form of lymphocytoma cutis, which can be misleading during clinical diagnosis.