Granulomatous slack skin: a rare subtype of mycosis fungoides

Abstract

We report a case of granulomatous slack skin, a rare and indolent subtype of mycosis fungoides. It affects mainly men between the third and fourth decades. It is characterized by hardened and erithematous plaques that mainly affect flexural areas and become pedunculated after some years. Histological examination shows a dense infiltrate of small atypical lymphocytes involving the dermis (and sometimes the subcutaneous tissue) associated with histiocytic and multinucleated giant cells containing lymphocytes and elastic fibers (lymphophagocytosis and elastophagocytosis, respectively). Patients affected by this entity can develop secondary lymphomas. There are several but little effective therapeutic modalities described. Despite the indolent behavior of granulomatous slack skin, its early recognition and continuous monitoring by a dermatologist becomes essential for its management and prevention of an unfavorable outcome.

Interstitial mycosis fungoides: A rare presentation of mycosis fungoides with overlapping granulomatous and folliculotropic features

“…However, the inflammatory mimickers of IMF often have benign and self‐limiting courses while the clinical course of IMF is more varied and less well understood 1 . In addition, IMF also exhibits overlapping features with other variants of MF such as folliculotropic MF and granulomatous slack skin syndrome (GSSS) 3,4 . Two case series have been published on the subject, but neither described the clinical presentation and course of IMF in detail 1,2 .…”

“…GSSS is characterized by pendulous skin folds in intertriginous areas with presence of granulomas, histiocytes, and multinucleated giant cells on histopathology. 3 Five patients in our cohort had features of GSSS at various stage of development from extensive wrinkling to slack intertriginous skin folds. Beyond these five patients, wrinkling was occasionally seen in our cohort (10; 32%).…”

“…Furthermore, our cohort also demonstrated overlapping features between IMF and GSSS. GSSS is characterized by pendulous skin folds in intertriginous areas with presence of granulomas, histiocytes, and multinucleated giant cells on histopathology 3 . Five patients in our cohort had features of GSSS at various stage of development from extensive wrinkling to slack intertriginous skin folds.…”

“…1 In addition, IMF also exhibits overlapping features with other variants of MF such as folliculotropic MF and granulomatous slack skin syndrome (GSSS). 3,4 Two case series have been published on the subject, but neither described the clinical presentation and course of IMF in detail. 1,2 Previous literature suggested that IMF is a purely histopathologic variant of MF consisting of interstitial lymphoid infiltrate with frequent CD8+ or CD4+/CD8+ phenotype but otherwise has a conventional clinical course.…”

Elastophagocytosis and interstitial granulomatous infiltrate are more common in extragenital vs genital lichen sclerosus

“…Elastophagocytosis is a non‐specific histopathologic finding of macrophage engulfment of elastic fibers and is associated with a number of inflammatory, infectious, and neoplastic disorders 12,16 . Elastophagocytosis is usually appreciated in actinic granuloma/annular elastolytic granuloma, 17 mid dermal elastolysis, 18 and granulomatous slack skin, a variant of mycosis fungoides associated with elastic tissue loss 19,20 . Less commonly, it is a feature reported in sarcoidosis, 21 necrobiosis lipoidica, 22 or infections such as leprosy 23 and blastomycosis 24 .…”