Malignant eccrine spiradenoma: a meta-analysis of reported cases.

BACKGROUND: Malignant eccrine spiradenoma is an aggressive sweat gland tumor with poorly understood behavior and no currently accepted therapeutic regimen. METHODS: An individual patient data meta-analysis with Kaplan­Meier survival curves was performed on 72 reported cases of malignant eccrine spiradenoma. RESULTS: In 35 patients with no distant metastasis, local resection resulted in 100% disease-free survival. Of 7 patients with lymph node but no distant metastasis treated with surgical resection and lymph node dissection, 6 patients remained disease-free at final follow-up evaluation. For the 24 cases with confirmed distant metastatic disease, patient survival did not significantly differ between local resection and surgery with adjuvant chemoradiotherapy (P = .8763). CONCLUSIONS: Heightened awareness is recommended among surgeons likely to treat this entity. An aggressive surgical approach is supported in the absence of metastasis. When lymph nodes are not clinically involved, sentinel node may have a role followed by lymph node dissection in patients with a positive node.

From hidroacanthoma simplex to poroid hidradenoma: clinicopathologic and immunohistochemic study of poroid neoplasms and reappraisal of their histogenesis.

BACKGROUND: Poroid neoplasms comprise classic poroma (P), hidroacanthoma simplex (HS), dermal duct tumor (DDT), and poroid hidradenoma (PH). The 3 latter are rarely reported. Poroid cells in P have recently been identified as keratinocytes of the lowermost acrosyringium and the sweat duct ridge. OBJECTIVES: To investigate a large cohort of poroid neoplasms to better define the clinical and pathologic aspects of HS, DDT, and PH. To analyze the expression of discriminatory keratins in all 4 poroid neoplasms. METHODS: 202 P, 11 HS, 17 DDT, 31 PH, and 5 composite tumors were examined under light microscopy, and 11, 9, 10, 15, and 2, respectively, by immunohistochemistry using anti-keratin antibodies, in particular, anti-K77, specific for luminal cells of the eccrine dermal sweat duct, and Ki-67 antibody. RESULTS: HS appeared later in life (66.6 years old) than P, DDT, and PH. Whereas P, DDT, and PH displayed unspecific clinical aspects, HS had most frequently the aspect of a large seborrheic keratosis with well-defined borders. HS, DDT, and PH were absent on palms and soles, but were found on the trunk, the lower limbs, and the upper limbs. Similar pathologic features were observed in all tumors, that is, a majority of poroid cells expressing K14, islands of K10-positive and K77-negative large cells. K77 expression was limited to luminal cells of intact ductal structures within the tumors. CONCLUSIONS: Our data demonstrate the common histogenesis of the 4 poroid neoplasms, which seem to derive from the basal keratinocytes of the sweat duct ridge and the lower acrosyringium. The variable length of the sweat duct ridge may account for the variety of poroid neoplasms, according to the site of tumor induction along this structure.

Unusual skin tumors: Merkel cell carcinoma, eccrine carcinoma, glomus tumors, and dermatofibrosarcoma protuberans.

This article discusses the epidemiology, etiology, presentation, pathology, evaluation and staging, and treatment of unusual skin tumors, such as Merkel cell carcinoma, eccrine carcinoma, glomus tumors, and dermatofibrosarcoma protuberans.

Mohs surgery for malignant eccrine neoplasms.

BACKGROUND: Eccrine carcinomas (ECs) are rare tumors with potentially aggressive clinical behavior and a high recurrence rate following conventional surgical excision. With the exception of microcystic adnexal carcinoma (MAC), there have been few reports on the use of Mohs micrographic surgery (MMS) as a primary treatment for EC. OBJECTIVE: To review the use of MMS for EC and compare treatment outcomes with those of conventional surgical excision. METHODS: We report our use of MMS in 7 cases of EC and review the literature regarding the use of MMS for EC excluding microcystic adnexal carcinoma (MAC), which has been described elsewhere. RESULTS: A total of 19 case reports describing MMS for non-MAS malignant eccrine neoplasms were reviewed. There were no reported recurrences over an average follow-up period of 29 months, whereas the local recurrence rate following conventional surgical excision of these neoplasms from 10-70%. CONCLUSIONS: While the clinical experience is limited, the use of MMS appears to decrease recurrence rates when compared to conventional surgical excision. Further experience and longer follow-up intervals will be necessary to demonstrate superior efficacy and recommended surgical margins.

Clear cell hidradenoma in a young girl.

Clear cell hidradenoma was diagnosed in a girl at 3(1/2) years of age. Only one case of hidradenoma has been documented in the first decade of life, although it remains unclear whether it was clear cell hidradenoma. This case demonstrates that clear cell hidradenoma is a rare differential diagnosis of cutaneous tumors even in young children, which is of special interest, because malignant transformations can occur.

Vulvar eccrine porocarcinoma.

A rare case of a slowly growing vulvar tumor in a 75-year-old woman is presented. This vulvar neoplasm was an eccrine porocarcinoma with left inguinal nodal metastases. This is believed to be only the second reported case of a vulvar eccrine porocarcinoma. Treatment included a left hemivulvectomy, bilateral inguinal-femoral lymphadenectomy, and postoperative radiation therapy. A review of the literature regarding this unusual malignancy is included.

Malignant eccrine neoplasms of the foot.

Eccrine cancers are uncommon, but potentially recurrent, metastatic and fatal. Rarely, they are primary foot lesions. The literature records 46 foot cases, with age and sex given for 41. Various eccrine cancer types (most on the sole), affected all races, males predominating. Average age at diagnosis was approximately 55. A podiatric facility recorded eight cases among approximately 30,000 skin biopsies, during 15 years. Seven arose in women. Five arose in the great toe area. Three are porocarcinomas. Five are "adenocarcinomas" varying in degree of differentiation. None of the eight patients presented recurrence or metastasis during follow-up 0.5-13.4 years. Of the combined 49 literature and podiatric cases, 28 (57.1%) arose in men, mostly between ages 41 and 70. Most were slow growing, long standing, and mildly symptomatic. No clinical features distinguished eccrine cancers from other pedal tumors.