Primary cutaneous small- to medium-sized CD4+ pleomorphic T-cell lymphoma: a retrospective case series and review of the provisional cutaneous lymphoma category

Abstract

Background and objective: Primary cutaneous small- to medium-sized CD4+ pleomorphic T-cell lymphoma (PCSM-TCL) is a rare and provisional subcategory of cutaneous T-cell lymphoma, associated with a favorable prognosis. We present five cases of PCSM-TCL and review the literature to address questions surrounding its diagnosis and treatment.

Methods: A retrospective review was conducted of 353 patients with non-mycosis fungoides cutaneous lymphomas evaluated at the M.D. Anderson Cancer Center Cutaneous Lymphoma Clinic over 10 years. A retrospective search of the English literature using PubMed was conducted to identify additional cases.

Results: Only five patients had a diagnosis of PCSM-TCL. Three patients had unique multifocal presentations that responded well to topical therapy or excision. One patient with localized disease initially treated with radiation therapy had an aggressive relapse requiring systemic therapy. One patient had an isolated nodule that fully resolved with excision. The review of the English literature found 232 additional cases. The presentation of PCSM-TCL was heterogeneous and included solitary/localized papules, nodules, plaques, and tumors. Multiple differential diagnoses were considered and PCSM-TCL diagnosis was based on histopathologic features and clinical correlation. Treatment of solitary/localized lesions included excision or radiation therapy. Multifocal lesions were uncommon and associated with an aggressive course requiring systemic chemotherapy.

Conclusions: The heterogeneous presentation, variable histologic overlap with other lymphoproliferative disorders, and uncertain prognosis of PCSM-TCL creates diagnostic and management dilemmas for clinicians. For treatment, a distinction should be made between indolent and aggressive subtypes. Further investigation is needed to determine if PCSM-TCL is indeed a distinct lymphoma category and, additionally, if aggressive subtypes should remain part of the same diagnostic category.