Coexistence of Eccrine Squamous Syringometaplasia and Graft-Versus-Host Disease in a Patient with Secondary Myelodysplastic Syndrome

Acquired elastotic hemangioma‐like changes and eccrine sweat duct squamous metaplasia in lichen simplex chronicus/prurigo nodularis‐like lesions of the knee and elbow

“…Another peculiar histopathological finding identified in all the lesions in our study was eccrine duct squamous metaplasia. Metaplastic epithelial changes of eccrine/apocrine ducts are well-known and are likely to represent a reactive process in non-neoplastic (such as inflammatory dermatoses, drug reaction, viral infection), 12,[26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43] and/or neoplastic conditions (ie, basal cell carcinoma, dermatofibrosarcoma protuberans, keratoacanthoma, squamous cell carcinoma), [44][45][46] or be associated with a benign (ie, tubular adenoma) or malignant sweat gland neoplasm (ie, apocrine adenocarcinoma). 47,48 Syringomatous changes of eccrine sweat glands have been documented in PN.…”

Eccrine Squamous Syringometaplasia Associated With Lichen Sclerosus et Atrophicus

“…The fibrosis and sclerosis may have contributed because it was also described in cases of plaque-type morphea, 6 linear scleroderma, 7 burns, 7 and GVHD. 8 Ischemia may lead to ESS in cases with skin ulcerations including pyoderma gangrenosum. Increased GLUT-1 and decreased VEGF expressions in LSA lesions suggest a role for hypoxia and ischemia, which might induce metaplastic ductal changes, the same way as in chronic ischemic ulcers.…”

Metaplasia mimicking malignancy: A challenging case of florid eccrine squamous syringometaplasia

“…Typically an incidental finding, ESSM was initially described as a form of appendageal acanthosis or pseudoepitheliomatous hyperplasia involving cutaneous appendages, 5 and may be considered analogous to necrotizing sialometaplasia in minor salivary glands 3 and lobular squamous metaplasia of the breast 6 . It is usually an adaptive or reactive response to ischemia, 2‐4 chronic trauma, 6 infections, 2 inflammatory dermatoses, 2,4 graft‐vs‐host disease, 7 tumors, 2,4,6 ulcers, 4,8 burns, 2,8 radiation, 2,6 and medications, such as chemotherapeutic agents 2,4,6,8 . Similar changes can be observed in neutrophilic eccrine hidradenitis, leading some to consider ESSM along the spectrum of chemotherapeutic eccrine gland reactions 2,6 .…”