Neurotropic Cutaneous Malignancies: Case Report on Keratinocyte Derived Malignancies of the Head and Neck With Perineural Invasion.

Background: The recent addition of immunotherapy as a treatment modality to surgery and radiation has vastly improved disease control for patients with keratinocyte-derived carcinomas (KCs) that are incurable with local therapies alone. With the advent of immune checkpoint inhibitors (ICPis) in non-melanoma skin cancers comes diagnostic and therapeutic challenges when considering treatment strategies for patients presenting with clinical perineural invasion (cPNI) of locally advanced KC of the head and neck.

Objectives: We report four cases that convey the diagnostic and therapeutic complexity of managing patients with neuropathic symptoms from cutaneous neurotropic carcinomas of the head and neck.

Latency-associated nuclear antigen expression and human herpesvirus-8 polymerase chain reaction in the evaluation of Kaposi sarcoma and other vascular tumors in HIV-positive patients.

Human herpesvirus-8 (HHV-8) latency-associated nuclear antigen (LANA) is expressed in endothelial and spindle cells of nearly all Kaposi sarcomas, and the presence of this antigen in serum is strongly correlated with the risk of developing Kaposi sarcoma in immunocompromised individuals. Studies of vascular tumors occurring in the general population show LANA expression to be specific for Kaposi sarcoma. No study to date, however, has examined whether non-Kaposi sarcoma vascular tumors arising in immunocompromised patients may express LANA, possibly reflecting origin from an HHV-8-infected endothelial progenitor cell.

Furunculosis due to Mycobacterium mageritense associated with footbaths at a nail salon.

We report two cases of lower-extremity furunculosis caused by Mycobacterium mageritense. Both patients were patrons of the same nail salon, where they received footbaths prior to pedicures. M.

Weight loss-induced calciphylaxis: potential role of matrix metalloproteinases.

Calciphylaxis is an uncommon and often devastating syndrome of calcification of small vessels, leading to tissue infarction. The mechanism of how calcium deposits on small vessels is unknown. Recently, metalloproteinase digestion of elastin has been shown to enhance deposition of calcium, suggesting a possible mechanism of calciphylaxis.

Proliferating trichilemmal tumors: clinicopathologic evaluation is a guide to biologic behavior.

Background: Trichilemmal (pilar) cysts are common skin lesions that usually occur on the scalp of elderly women. They differentiate towards the follicular outer root sheath epithelium and show trichilemmal keratinization. Proliferating trichilemmal tumor (PTT) shows features of typical pilar cyst, but additionally shows extensive epithelial proliferation, variable cytologic atypia and mitotic activity.