Unilateral Ulcerating Clear-Cell Syringomas Involving Left Groin in a Non-Diabetic Woman - Report of a Rare Presentation.

Clear-cell syringomas, a rare histologic variant of syringomas, frequently coexist with diabetes mellitus. Clinically, it presents as skin colored papules distributed symmetrically around periorbital region. However, asymmetrical distribution of syringomas is rare and much rarer is the ulceration in such syringomas. Ulceration in such asymmetrical syringomas has not been reported so far. Herein, we report ulceration of clear-cell syringomas involving left groin in a middle aged non-diabetic woman.

What was known?

Syringomas usually present as skin colored papules distributed symmetrically around periorbital region. Clear-cell syringomas, a distinct histopathological variant of syringomas is frequently associated with diabetes mellitus.

Introduction

The name syringoma is derived from the Greek word syrinx, which means pipe or tube. Syringomas are benign adnexal neoplasms derived from the intraepidermal portion of eccrine sweat ducts,[1] usually present as asymptomatic skin colored papules around periorbital area.[2] Clear-cell syringomas, a rare histologic variant of syringomas frequently coexist with diabetes mellitus.[3] Ulceration in syringomas hitherto has not been reported. Here, we report unilateral ulcerating clear cell syringoma in a middle aged non- diabetic lady involving left groin.

Case Report

A 60 -year-old lady came to the department with a painful swelling and ulcer in the left groin of 1-year duration. Initially, she developed a painful papule followed by development of few more to form a plaque which subsequently ulcerated to discharge serous fluid. There after she continued to suffer from pain and discharge intermittently. There was no association with fever, cough or weight loss. Cutaneous examination revealed indurated plaque of size 2 cms × 1.5 cms in the left groin with multiple papules and erosion on the surface [Figure 1]. Two discrete lymph nodes were palpable in left inguinal region. Based on these findings she was provisionally diagnosed as a case of scrofuloderma. Actinomycosis, granuloma inguinale, hydradenitis suppurativa and botryomycosis were considered in the differential diagnosis. Routine laboratory investigations: Complete blood picture, blood sugar, blood urea, serum creatinine, X-ray chest, ultrasonography of abdomen were found to be normal. Mantoux-test was negative. Smear and culture for acid fast bacilli and for fungus were negative. Swab for bacterial culture did not yield any growth. Skin biopsy showed numerous tubular structures lined by cuboidal epithelium arranged in single and double rows in the dermis. Some of these cells showed clear cytoplasm [Figures 2 and 3]. Immunohistochemistry was strongly positive for AE1 and AE3 marker, [Figure 4] which confirmed the diagnosis of clear-cell syringoma. As there is deep involvement in the reported case surgical excision is probably ideal. However, the case is lost to follow up.

Figure 1

Indurated plaque with multiple papules and erosion in the left groin

Figure 2

H and E stain ×10. Dermis showing tubular structures in single and double rows, some of them having tadpole appearance

Figure 3

H and E, stain ×40. Dermis showing numerous tubular structures lined by cuboidal epithelium arranged in single and double rows with clear cytoplasm in few of them

Figure 4

Immunohistochemistry ×40 showing AE1 and AE3 positive cells throughout dermis

Discussion

Syringomas are common in females and occur frequently before and around puberty.[4]

The influence of hormones on the syringomatous reaction was supported by aggravation or manifestation of vulvar syringomas during pregnancy[5] and also association of pruritus with menstrual cycle.[6] It was further established by detection of estrogen and progesterone receptors in them.[7]

Four clinical variants have been described: (i) local, (ii) disseminated, (iii) syringoma associated with Down syndrome, (iv) inherited forms.[2] Common site of involvement is periorbital area but may affect the scalp, forehead, neck, abdomen and extremities. However, groin involvement on one side in the index case is rare and interesting. Syringomas are usually asymptomatic but pruritus may be presenting symptom.[89] However, pain was the presenting symptom in the case under study. Clear-cell syringomas represent rare histologic variants of syringomas with a bright and clear cytoplasm of the ductal epithelial cells due to increased content of intracellular glycogen which is due to phosphorylase deficiency in diabetics.[10] These syringomas are clinically indistinguishable from ordinary syringomas and are considered as a cutaneous marker for diabetes mellitus.[11] Surprisingly, various studies on syringomas did not substantiate association between clear-cell syringomas and diabetes mellitus.[8912] Furthermore, the index case is also a case of clear-cell syringomas histopathologically, not associated with diabetes mellitus. Wilms and Douglass have reported preponderantly right sided syringomas in their case report.[13] However, ulceration of the syringomas has not been described so far. Interestingly, the case under study presented with syringomas with ulceration involving only left groin (unilateral).

Syringomas simulating urticaria pigmentosa[14] and milia[2] have also been described. Chronic inflammatory process of the skin involving adnexal structures such as scarring alopecia,[15] prurigonodularis[16] and following radiotherapy[17] are also known to result in the development of syringomas. However, there was no history of such underlying local chronic inflammation in the index case.

Most syringomas are benign and aesthetically-disfiguring. Regression of lesions in adulthood has been observed, but is exceptional. Treatment modalities include topical or systemic retinoids[18] electrodessication,[19] laser ablation, cryosurgery, dermabrasion. However, all therapeutic options bear the risk of recurrence. Recently, there have been reports of successful treatment of syringoma with topical atropine.[20]

In conclusion, it may be said that dermatologist should be aware of atypical presentations of syringomas such as asymmetry and ulceration. Strong suspicion and biopsy with immunohistochemistry will help in diagnosing and treating such rare presentations.

What is new?

We hope to highlight the importance of repeat biopsies in unusual cases of high suspicion of rare diseases such as SPTCL when initial biopsies are non-diagnostic, and to emphasize the importance of immunohistochemical analysis