Eccrine syringofibroadenoma: Sweating over the details

By Warren R. Heymann, MD, FAAD
January 26, 2022
Vol. 4, No. 4

While learning about rare entities during our training, we may wonder if we will ever encounter the disorders in “real life.” Eccrine syringofibroadenoma (ESFA), first described in 1963 by Mascaro, was considered a relatively “new” lesion when I was a dermatopathology fellow. I was taken with its striking, distinctive, beautiful (to my eye) histologic appearance of proliferating cords of epithelial cells, with ductal luminae, surrounded by a fibrovascular stroma. (1) Over the ensuing decades, I have only infrequently encountered the lesion (usually in the literature). Recently, I had a “Rip Van Winkle” experience when I diagnosed ESFA on a lesion sent in as a squamous cell carcinoma. Reviewing manuscripts on something I had not thought much about in 37 years was revelatory —the world of ESFA has changed.

My concept of ESFA was that of a solitary benign neoplasm. While that is true in some cases, ESFA may present in diverse ways, including multiple lesions known as eccrine syringofibroadenomatosis. Is ESFA a neoplasm, hamartoma, or reactive process? As stated by Takeda et al, “it is impossible to attribute ESFA to a single cause and ESFA is probably a group of heterogeneous disorders clinically and pathogenically.” (2)

Currently, there are 5 variants of ESFA, all of which share common histopathologic features. ESFA are classified according to clinical presentation and associated findings:

1. Solitary ESFA, which often presents as a single nodule on the extremities of elderly individuals; clinically, this resembles a verruca or pyogenic granuloma;

2. Multiple ESFA (syringofibroadenomatosis), without associated cutaneous findings, characterized by multiple lesions with a linear and symmetrical arrangement or with a palmoplantar distribution — the appearance may be papular, psoriasiform, and keratodermatous, with fissures and erosions;

3. Multiple ESFA associated with hidrotic ectodermal dysplasias (notably the Schöpf-Schulz-Passarge syndrome [due to mutations of WNT10A manifested by hypodontia, hypotrichosis, keratoderma, and periocular hidrocystomas] and Clouston syndrome [hidrotic ectodermal dysplasia due to a mutation in GLB6]);

4. Nonfamilial unilateral linear ESFA, described as unilateral plaques and papules in a linear arrangement, likely due to mosaicism; and

5. Reactive ESFA, characterized by reactive epithelial and eccrine ductal changes secondary to inflammatory or neoplastic disorders, including erosive lichen planus, bullous pemphigoid, leprosy, chronic diabetic foot ulcer, burn scar, venous stasis, elephantiasis, ileostomy stoma, cutaneous amyloidosis, nevus sebaceous basal cell carcinoma, and squamous cell carcinoma. (1,3,4,5,6,7)

Realistically, only the most elite clinicians will consider the diagnosis of ESFA (with the possible exception of already having diagnosed one of the ectodermal dysplasias) prior to receiving the biopsy report. Rendering the diagnosis of ESFA is more than an academic dermatopathological exercise — it may have important clinical implications.

For example, Hays et al reported the case of a basal cell carcinoma of the right shin of a 77-year-old man that was surrounded by a large erythematous plaque. Recognizing ESFA due to long-standing venous stasis, instead of one of its mimickers — fibroepithelioma of Pinkus — was essential in limiting the patient’s surgery. (7) It is standard operating procedure to biopsy the edge of recalcitrant ulcers to determine if the lesion is a keratinocyte carcinoma, especially if there is a verrucous appearance. Reactive ESFA should be considered in this context. (8)

Although considered benign by most authorities, there have been scattered reports of ESFA becoming malignant; so-called “syringofibrocarcinoma.” Pagliuca et al report the case of a 76-year-old man with a long-standing ESFA of the left forearm demonstrating carcinomatous transformation. (9) The authors reasonably suggest complete excision of solitary ESFA lesions. For the other ESFA variants, surgical excision may be considered (if small enough to be amenable) and treatment of associated disorders is warranted (such as compression for associated venous stasis). Variable success has been reported with 5-fluorouracil, imiquimod, photodynamic therapy, and radiotherapy. (1)

In conclusion, it is essential for dermatologists to understand the clinical context upon receiving a histologic diagnosis of ESFA for proper patient management. There is one other aspect of ESFA that I wish to mention. Saying eccrine syringofibroadenomatosis out loud brings me joy. I imagine that is how Mary Poppins feels when she says supercalifragilisticexpialidocious.

Point to Remember: Diagnosing eccrine syringofibroadenoma warrants careful clinical-pathologic correlation to address proper management for one of its five variants.

Our expert’s viewpoint

Kiran Motaparthi, MD, FAAD
Associate Professor
Residency Program Director
Director of Dermatopathology
Department of Dermatology
University of Florida College of Medicine

In practice, the most common scenario to observe ESFA is as a reactive phenomenon, particularly in excisions from the lower extremities of elderly patients. Thus, recognition of the characteristic features of EFSA — anastomosing strands of basaloid epithelium with epidermal connection and ductal differentiation — is of particular relevance in distinguishing this benign adnexal proliferation from residual basal or squamous cell carcinoma. This is especially important in avoiding overdiagnosis of keratinocyte carcinoma when reviewing frozen sections from Mohs micrographic surgery. The characteristic fibrovascular stroma and abundant plasma cells are supportive clues in cases with subtle features. When considering the differential diagnosis of fibroepithelioma of Pinkus, mucin deposition, stromal-epithelial retraction, and a palisading epithelium without ductal differentiation readily allow distinction from EFSA.

1. Chukwuma O, Walker A, Motaparthi K, Montanez-Wiscovich M. Recalcitrant erosive plaques on the palms and soles: A rare manifestation of eccrine syringofibroadenoma. JAAD Case Rep. 2020 May 15;6(7):590-592.

2. Takeda H, Mitsuhashi Y, Hayashi M, Kondo S. Eccrine syringofibroadenoma: case report and review of the literature. J Eur Acad Dermatol Venereol. 2001 Mar;15(2):147-9.

3. Zhou P, Li F, Liu H, Wang L. Solitary Eccrine Syringofibroadenoma of the Dorsum of Hand. Indian J Dermatol. 2020 Nov-Dec;65(6):560-561.

4. Lui H, Stewart WD, English JC, Wood WS. Eccrine syringofibroadenomatosis: a clinical and histologic study and review of the literature. J Am Acad Dermatol. 1992 May;26(5 Pt 2):805-13.

5. Riera-Monroig J, Martínez-Romero MDC, Alós L, Guillén-Navarro E, Mascaró JM Jr. Eccrine syringofibroadenoma as a clue for the diagnosis of Schöpf-Schulz-Passarge syndrome in acquired palmoplantar keratoderma. J Cutan Pathol. 2020 Oct;47(10):987-989

6. Starink TM. Eccrine syringofibroadenoma: multiple lesions representing a new cutaneous marker of the Schöpf syndrome, and solitary nonhereditary tumors. J Am Acad Dermatol. 1997 Apr;36(4):569-76.

7. Hays JP, Malone CH, Goodwin BP, Wagner RF Jr. Reactive Eccrine Syringofibroadenoma Associated With Basal Cell Carcinoma: A Histologic Mimicker of Fibroepithelioma of Pinkus. Dermatol Surg. 2018 May;44(5):738-740.

8. Tedbirt B, Carvalho P, Boulard C, Tetart F, Deschamps-Huvier A, Chenal P, Courville P, Cellier L, Joly P. Reactive Eccrine Syringofibroadenomatosis Associated With Venous Leg Ulcers: A Case Report and Literature Review. Int J Low Extrem Wounds. 2020 Oct 20:1534734620966900.

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