Clinical spectrum of indolent mycosis fungoides with a gamma-delta (γδ) phenotype: a single institution review including therapy and outcomes

Background

Primary cutaneous γδ T-cell lymphoma (CGD-CTL) is a rare malignancy that classically exhibits an aggressive clinical phenotype.

Objectives

Review cases of mycosis fungoides with a γδ phenotype that demonstrated an indolent clinical course.

Methods

Retrospective review of patients diagnosed with MF with a γδ phenotype and an indolent clinical course between 2018 and 2022 treated at the University of Utah.

Results

Five patients ages 4-81 years old were identified. All presented with clinically persistent patch or plaque-stage disease, and histopathology showed primarily epidermotropic infiltrates positive for TCR delta via immunostaining. None of these patients have required aggressive treatment with multiagent chemotherapy.

Conclusions

There exists a subset of indolent CGD-TCL patients who are clinicopathologically distinct from classic CGD-CTL and clinically resembling indolent MF. Therefore, we prefer the term “MF with γδ phenotype” for these rare cases.