Extraordinary Case ReportSyringotropic Mycosis Fungoides A Rare Form of Cutaneous T-cell Lymphoma Enabling a Histopathologic “Sigh of Relief”Lehmer, Larisa M. MD, MA*; Amber, Kyle T. MD†; de Feraudy, Sébastien M. MD, PhD†Author Information Departments of *Internal Medicine, and †Dermatology, UC Irvine Health, Irvine, CA. Reprints: Sébastien M. de Feraudy, MD, PhD, Dermatopathology Laboratory, UC Irvine, 101 City Drive, Building 52, Room 125, Mail Route 98/Zot Code 2400, Orange, CA 92868 (e-mail: email@example.com). The authors declare no conflicts of interest. The American Journal of Dermatopathology: December 2017 - Volume 39 - Issue 12 - p 920-923 doi: 10.1097/DAD.0000000000000926 Buy Metrics Abstract Abstract: Syringotropic mycosis fungoides (STMF) is a very rare variant of cutaneous T-cell lymphoma. It follows a much milder disease course than its clinically indistinguishable adnexal counterpart, folliculotropic mycosis fungoides (FMF). We report a case of a 36-year-old man who presented with erythematous, studded papules and plaques on the left upper extremity and right anterior thigh diagnosed as mycosis fungoides (MF) Stage 1A on initial superficial shave biopsy. Lesions recurred after initial improvement with narrow-band ultraviolet light therapy demonstrating a concentration of abnormal lymphocytes around eccrine sweat glands on repeat biopsy consistent with STMF. Although the deeper, periadnexal infiltrate found in both STMF and FMF confers increased resistance to skin-directed therapies effective in classic MF, these entities diverge with respect to their clinical behavior. Syringotropism is a marker for increased disease-specific survival, whereas even FMF carries a prognosis worse than conventional MF. Increased awareness among the dermatopathology community of the histopathologic distinction between STMF and FMF is essential to guide treatment type, duration, and intensity in adnexal disease. Copyright © 2017 Wolters Kluwer Health, Inc. All rights reserved.