Primary Cutaneous Anaplastic Large Cell Lymphoma With TCR-γδ Expression: A Case Series of Eleven Patients of a Rare Immunophenotypic Variant

Abstract

Background

Primary cutaneous anaplastic large cell lymphoma (pcALCL) and lymphomatoid papulosis (LyP) are indolent CD30-positive lymphoproliferative disorders that rarely express TCR-γδ. However, primary cutaneous gamma-delta T-cell lymphoma (pcGDTCL), characterized by TCR-γδ expression on neoplastic cells, is a rare, aggressive cutaneous T-cell lymphoma with a poor prognosis. Accurate differentiation is essential due to distinct clinical behavior and treatment.

Methods

We identified 11 TCR-γδ-positive pcALCL cases from internal and consultation files, verified by two cutaneous lymphoma experts, with clinicopathologic data recorded.

Results

The median age was 68 years (range 38–95). Most cases presented as a single dermal lesion on the upper extremities. All were ALK-negative, CD30-positive (> 90% tumor cells), TCR-βF1-negative, and diffusely TCR-γδ-positive. CD4−/CD8− (54.5%) and CD4+/CD8− (45.5%) immunophenotypes were observed. CD2 (63.6%) and CD3 (54.5%) were the most common T-cell antigens. Ulceration, inflammation (both 45.5%), and necrosis (36.4%) were frequent. Angiotropism, angiocentricity, and myxoid stroma appeared in one case; epidermotropism in two. Four of ten tested were DUSP22-rearranged, and TP63 was negative in all eight tested.

Conclusions

Most ALK-negative TCR-γδ-positive pcALCL were CD4−/CD8−, followed by CD4+/CD8−. DUSP22 rearrangement occurred in 40% of cases, similar to reports in typical pcALCL. Its prognosis and the role of DUSP22 are yet to be clarified.