History
Malignant eccrine tumors generally present as a single, asymptomatic, nondescript cutaneous lesion. Eccrine carcinomas account for less than 0.01% of all cutaneous appendageal carcinomas. [9] The most commonly affected age group is those in their seventh decade of life, and it equally affects men and women.
Eccrine carcinomas tend to be solitary, locally invasive lesions that grow slowly over many years; local tumors represent 84.9% of tumors. [7] Rarely, they may develop quickly, reaching a size of several centimeters over a few months. Metastasis is rare (3.2%). [7] With disseminated disease, patients may report symptoms related to organ-specific metastases.
Physical
Cutaneous/primary lesion of eccrine carcinoma
A solitary nontender, nonencapsulated nodule or plaque on the head or extremities and, less commonly, the trunk is present. Occasionally, the lesion may ulcerate. A few tumor subtypes do exhibit salient clinical features, as follows:
-
Microcystic adnexal carcinoma (MAC): Occurs as an indurated plaque especially in the nasolabial area
-
Aggressive digital papillary adenoma/adenocarcinoma: Typically is seen in males on the digits and adjacent skin
-
Hidradenocarcinoma: Most occur on the head and neck of older patients
-
Eccrine porocarcinoma: Most are found on the lower extremities of older adults (see the images below)
Eccrine porocarcinoma. Courtesy of DermNet New Zealand (http://www.dermnetnz.org/topics/eccrine-porocarcinoma/).
Eccrine porocarcinoma. Courtesy of DermNet New Zealand (http://www.dermnetnz.org/topics/eccrine-porocarcinoma/).
Disseminated eccrine carcinoma disease
Nodal and distant metastases may be detected. In particular, eccrine porocarcinoma (the most common eccrine cancer subtype) shows a characteristic propensity to produce multiple cutaneous metastatic deposits concomitant with visceral spread.
Causes
Risk factors for eccrine carcinoma include family history, immunosuppression, and ultraviolet radiation (UVR). [7] . A case of MAC was reported in the neck of a man who received radiation therapy to the site years earlier. In addition, Abbate et al [4] report that 5 of 10 patients with MAC gave a prior history of radiation therapy. Chiller et al [15] report a potential etiologic role for UVR as they describe MAC predominantly affecting the left side of the face, corresponding to higher UVR exposures while driving.
Immunosuppression has been known to increase the risk of nonmelanoma skin cancers, particularly squamous cell carcinomas. In a 2003 retrospective review of appendageal tumors in organ transplant recipients, Harwood et al [16] suggest that patients who are immunosuppressed have a propensity to also develop cutaneous appendageal tumors over their immunocompetent counterparts, with increased rates of both benign eccrine tumors and malignant eccrine tumors.
Complications
Eccrine carcinomas may cause complications secondary to local invasion or metastatic disease.
-
Eccrine porocarcinoma. Courtesy of DermNet New Zealand (http://www.dermnetnz.org/topics/eccrine-porocarcinoma/).
-
Eccrine porocarcinoma. Courtesy of DermNet New Zealand (http://www.dermnetnz.org/topics/eccrine-porocarcinoma/).
-
Eccrine carcinoma pathology. Basaloid cells invading the dermis. Courtesy of DermNet New Zealand (http://www.dermnetnz.org/topics/eccrine-carcinoma-pathology/).
-
Eccrine carcinoma pathology. Tubule and gland formation infiltrating the sclerotic dermis; eccrine differentiation can be seen at high power. Courtesy of DermNet New Zealand (http://www.dermnetnz.org/topics/eccrine-carcinoma-pathology/).
-
Eccrine carcinoma pathology. Tubule and gland formation infiltrating the sclerotic dermis; eccrine differentiation can be seen at high power. Courtesy of DermNet New Zealand (http://www.dermnetnz.org/topics/eccrine-carcinoma-pathology/).
-
Eccrine carcinoma pathology. Tubule and gland formation, along with clear cell change. Courtesy of DermNet New Zealand (http://www.dermnetnz.org/topics/eccrine-carcinoma-pathology/).
