Eccrine Syringofibroadenoma and Clear Cell Acanthoma: An Association by Chance?

Eccrine Syringofibroadenoma in a Patient with Long-Standing Exfoliative Dermatitis

Eccrine syringofibroadenoma (ESFA) is a rare benign cutaneous adnexal lesion characterized by a hyperplastic epithelium and eccrine ductal differentiation. In the present case, a 73-year-old Korean male presented with symmetrical numerous widespread, pinkish nodules with a cobblestone appearance over both legs for 2 years. He had a history of generalized erythematous scaly patches over his entire body for 20 years. On histopathologic findings, diagnosis of ESFA was confirmed. Our unusual and interesting case emphasizes the first report described one case in which multiple cobblestone like ESFAs arising from long-standing exfoliative dermatitis.

A Solitary Facial Nodule with an Uncharacteristic Histopathology

Collision or contiguous tumors refer to the combined existence of two or more tumors in a single lesion. In the skin, these growths could closely mimic other cutaneous tumors, thus making diagnosis difficult. We hereby report a dual tumor, comprising pilomatricoma, and eccrine syringofibroadenoma, which to the best of our knowledge have not been previously reported in medical literature.

Reactive eccrine syringofibroadenomatosis secondary to primary cutaneous amyloidosis: a novel association

We report the unprecedented case of reactive eccrine syringofibroadenoma (ESFA) secondary to primary cutaneous amyloidosis. A 62-year-old woman of Asian ethnicity presented with a pruritic rash on the back of long-standing duration. Physical examination revealed diffuse hyperpigmentation localized to the interscapular region; there were a multitude of hyperpigmented macules merged in a rippled pattern intermixed with scattered papules and cobblestone-like areas. A punch biopsy from a papule was taken. Histopathological examination revealed a network of epithelial strands and cords hanging from the epidermis and harboring foci of ductal differentiation. Eosinophilic collections of amorphous material were found between the epithelial strands, obscuring the superficial dermis. The microscopic picture was consistent with primary cutaneous amyloidosis associated with reactive ESFA. Results of histochemical and immunohistochemical staining confirmed the diagnosis. We speculate that pathogenetic mechanisms intrinsic to primary cutaneous amyloidosis, in addition to unknown genetic factors, resulted in clinical changes of lichen amyloidosus associated with an abnormal hyperplastic epithelial response with histopathological features of ESFA rather than the common epidermal change of acanthosis and hyperkeratosis.

Clear cell acanthoma with changes of eccrine syringofibroadenoma: reactive change or clue to etiology?

We observed two patients with solitary lesions showing features of clear cell acanthoma with underlying eccrine syringofibroadenoma-like changes. The pathogenesis of these entities has been debated since their original descriptions, with most recent literature suggesting that both may represent reactive phenomena rather than true neoplasms. Our observation prompted us to perform a retrospective review of clear cell acanthoma cases to determine the frequency of such associated eccrine syringofibroadenoma changes. Of 47 examined cases of clear cell acanthoma, 9 (19%) showed associated changes of eccrine syringofibroadenoma. Immunohistochemical evaluation performed on a subset of cases identified similar but slightly divergent differentiation patterns within the lesions. While epithelial membrane antigen and PAS expression were similar in both components (although slightly different in intensity), the regions resembling eccrine syringofibroadenoma displayed additional immunoreactivities, supporting the presence of two distinct components. We have found that the concurrence of clear cell acanthoma with syringofibroadenomatous changes is more frequent than generally appreciated and suggest that these entities may share derivation from the eccrine apparatus.