CD8⁺ granulomatous cutaneous T-cell lymphoma: A potential association with immunodeficiency

Background Granulomatous cutaneous T-cell lymphoma (G-CTCL) is a rarely encountered entity. Most G-CTCL is CD4⁺, with granulomatous mycosis fungoides representing the vast majority of cases. Because of the rarity of CD8⁺ G-CTCL, there is a paucity of data regarding the clinicopathologic features and expected course. Objective To describe the clinical and histopathologic features of G-CTCL. Methods This is a retrospective review of collected cases. Results We present 4 cases of CD8⁺ G-CTCL. Patients presented with papules and nodules on the trunk and extremities without antecedent patch or plaque disease. In all cases, biopsy specimens were obtained, and these revealed a dense granulomatous infiltrate accompanied by an atypical lymphoid infiltrate of CD8⁺ T cells. T-cell clonality studies were positive in 3 of 4 cases. Staging was negative for nodal involvement, but lung granulomas were seen in all cases. In all 4 cases, the patient's medical history was significant for immunodeficiency, either primary or iatrogenic. All 4 patients had slowly progressive disease. Limitations This is a small retrospective case series. Conclusions CD8⁺ G-CTCL appears to be associated with immunodeficiency. The finding of a CD8⁺ G-CTCL should prompt an evaluation for underlying immunodeficiency. Additional studies are required to validate these conclusions.