Biphasic Sarcomatoid Porocarcinoma

Eccrine Porocarcinoma of the Vulva With Sarcomatoid Transformation, a New Human Papillomavirus-associated Malignancy? Case Report and Review of the Literature

Eccrine porocarcinoma is a rare cutaneous neoplasm, and rarer still in the anogenital region. In the vulva, the most common carcinoma by far is squamous cell carcinoma; however, eccrine porocarcinoma can arise at this site. As the distinction between porocarcinoma and squamous cell carcinoma has important prognostic implications at other cutaneous sites, it stands to reason that it may have these same implications in the vulva. We present a case of an eccrine porocarcinoma in the vulva of a 70-year-old woman that, in addition, showed sarcomatoid transformation. This tumor harbored human papillomavirus-18 DNA and mRNA, raising the question of the role of the oncogenic virus in sweat gland neoplasms of the vulva.

When to sweat: A history of chemotherapy in malignant sweat gland tumors. A unique case report and literature review

Sarcomatoid sweat gland carcinomas are rare among cutaneous cancers, with less than 20 cases described. A 54-year-old woman with sarcomatoid sweat gland carcinoma of the right upper extremity suffered extensive recurrence at 15 months, unresponsive to chemotherapy. There is no standard treatment or chemotherapy regimens for metastatic sweat gland carcinoma.

Porocarcinoma with areas of mucinous differentiation suggesting multilineage differentiation

Porocarcinoma is an infrequent malignant adnexal carcinoma, with some histopathological variants described, such as the clear cell, the sarcomatoid or the pigmented porocarcinoma. We report an invasive porocarcinoma showing areas of tumor cells floating in prominent dermal mucin, simulating mucinous carcinoma, that we consider a new histopathological variant of porocarcinoma. We report a 74-year-old male with previous history of multiple basal cell carcinomas that presented a nodule on his left temple. Histopathologic study showed a large ulcerated multilobular tumor composed of thickened cords of cells emanating from a hyperplastic epidermis and showing a mixed infiltrative and pushing pattern in the dermis. Poroid differentiation was observed in most of the neoplasm, both in intraepidermal and dermal invasive component. Within the neoplasm a prominent area where these small nests with clear formation of ducts were floating in mucinous pools with few septa intermingled was observed, simulating a primary cutaneous mucinous carcinoma. Cytology, immunohistochemistry and the presence of both neoplastic areas as closely related and with multiple points of connectivity favors the consideration of a composite tumor in this peculiar case. Other differentials are discussed.

Primary cutaneous biphasic sarcomatoid basal cell carcinoma with myoepithelial carcinoma differentiation: A new variant

Isolated cases of basal cell carcinoma (BCC) with partial myoepithelial component have been described. However, myoepithelial differentiation has not been described in sarcomatoid basal cell carcinomas, which usually show features resembling osteosarcoma, chondrosarcoma, or leiomyosarcoma. We report a case of an 87-year-old man with a forehead lesion that histologically showed a minor component of conventional nodular BCC in transition with a major biphasic sarcomatoid growth composed of invasive spindle-cell and epithelial-like components, the latter with a reticular pattern and scattered ductal structures. Both components showed cytological atypia and high mitotic rate (26/10HPF), with atypical mitotic figures. BER-EP4 immunostaining was exclusively found in the nodular BCC component whereas the sarcomatoid component revealed immunostaining for α-smooth muscle actin (SMA), muscle-specific actin (MSA), calponin, and p63 in both epithelial-like and spindle-cell populations. Focal immunoreactivity was observed in the epithelial component for S100 and glial fibrillary acidic protein (GFAP). Furthermore, EWSR1-PBX1 gene fusion was also detected. This is to our knowledge, the first fully documented case of biphasic sarcomatoid BCC with myoepithelial carcinoma differentiation.

Collision Tumor Associated with Sarcomatoid Eccrine Porocarcinoma and Basal Cell Carcinoma

A ‘collision’ tumor refers to the existence of two different neoplasms within the same tumor. Sometimes, the term ‘biphasic tumor’ is also used. However, a ‘collision’ tumor is defined as the occurrence of two neoplasms within proximity of each other yet maintaining distinctly defined, separate boundaries. In contrast, a ‘biphasic’ tumor demonstrates two or more phenotypically distinct neoplastic cell populations merging within the same space. Here, we report a case of collision tumor associated with sarcomatoid eccrine porocarcinoma and basal cell carcinoma arising in a 57-year-old male patient.

Cutaneous Collision Tumor Associated With Porocarcinomatous and Angiosarcomatous Components: A Potential Diagnostic Pitfall

Sarcomatoid eccrine porocarcinoma (SEP) is a very rare malignancy including epithelial and mesenchymal components exhibiting pleomorphic cells, nuclear hyperchromasia, and high mitotic activity in both elements. To date, only 6 cases of this uncommon neoplasm have been reported, corresponding to women over 70 years of age with ulcerated skin lesions. The authors describe the first sarcomatoid eccrine porocarcinoma in a 75-year-old male patient with a right hallux lesion, presenting a collision tumor with a mixed population of epithelial cells and a spindle cell angiosarcomatous mesenchymal component each expressing distinct and nonoverlapping morphologic and immunohistochemical features of epithelial and mesenchymal differentiation.

Porocarcinoma scalp with high risk features treated with surgery and adjuvant radiotherapy: A case report and review of literature

Eccrine porocarcinoma is a rare malignant sweat gland tumor arising from the intra dermal part of the gland and accounts for only 0.005% of all epithelial cutaneous tumors. Commonly involved site includes extremities and face. Scalp is a rare site for porocarcinoma with less than 20 reported cases so far. Wide local excision with clear margins remains the treatment of choice. Review of literature revealed a local recurrence rate of 37.5% and a nodal involvement risk of 20%. Porocarcinoma of the scalp is peculiar in that the primary tumor may be large at presentation, making surgery with adequate margins difficult. Adjuvant radiotherapy must be considered in a case to case basis due to the high local recurrence rates compared to other sites of porocarcinoma and should be given to all patients with close margins and extra capsular extension.