Prominent tissue hemophagocytic lymphohistiocytosis obscuring primary cutaneous gamma/delta (γδ) T-cell lymphoma.

Primary cutaneous gamma/delta (γδ) T-cell lymphoma (PCGDTCL) is a rare, aggressive malignant neoplasm of γδ T lymphocytes arising within the skin and subcutis. We present a challenging case of PCGDTCL diagnosed in a 35-year-old male soldier who presented with constitutional symptoms, pancytopenia, hemophagocytic lymphohistiocytosis (HLH), disseminated lymphadenopathy, and cutaneous lesions on his extremities and back following a deployment to Iraq and Syria. Histopathologic evaluation of an excisional biopsy showed that PCGDTCL can be focal, localized to the subcutaneous adipose tissue, and obscured by predominant HLH in the surrounding tissues.

Granulomatous Cheilitis Preceding Gastrointestinal Manifestations of Crohn's Disease.

We describe a 20-year-old male with no significant medical history who presented with a 1-month history of painless upper and lower lip edema initially treated with antibiotics for suspected cellulitis before arriving to the clinic. After a failed response to that treatment, a lip biopsy was eventually performed and consistent with a diagnosis of granulomatous cheilitis. In addition to oral and topical corticosteroids and tacrolimus, the patient adopted the cinnamon- and benzoate-free diet with some improvement of his lip swelling.

Fulminant Pyoderma Gangrenosum After Outpatient Knee Arthroscopy.

Pyoderma gangrenosum is an immunologic, ulcerative cutaneous condition often associated with systemic disease and frequently precipitated by trauma. It is noninfectious, but the inflammatory assault can resemble a malignant infection such as necrotizing fasciitis. Despite its clinical resemblance to infection, surgical débridement worsens the condition and may remove morphologic clues to the true disease, thus creating a vicious cycle of surgical débridements and disease progression.

Case report: Hansen's disease in an active duty soldier presenting with type 1 reversal reaction.

Leprosy, or Hansen's disease (HD), is caused by the bacterium and is a significant cause of morbidity worldwide. Clinical manifestations range from isolated skin rash to severe peripheral neuropathy. Treatment involves a prolonged course of multiple antimicrobials.

Delayed Diagnosis of Leprosy in a Micronesian Soldier - Case Report.

Lepromatous leprosy represents a cutaneous infection by the bacterium Mycobacterium leprae. Once considered a common, fatal disease, leprosy has become increasingly rare with modern, inexpensive antibiotics. Most healthcare workers will never encounter a case of leprosy due to the low prevalence of the disease.

A Comparison of the Histopathologic Growth Patterns Between Non-Merkel Cell Small Round Blue Cell Tumors and Merkel Cell Carcinoma.

Background: Merkel cell carcinoma (MCC) is a rare neuroendocrine cutaneous malignancy that shares cytologic, histopathologic, and immunohistochemical features with other small round blue cell (SRBC) tumors. Although the trabecular pattern is anecdotally associated with MCC, objective data are lacking.

Methods: This was a retrospective institutional review board-approved observational study conducted on microscopic images of 79 MCCs and 74 other SRBC tumors (desmoplastic small round cell tumor, primitive neuroectodermal tumor, neuroblastoma, embryonal rhabdomyosarcoma, alveolar rhabdomyosarcoma, synovial sarcoma, carcinoid, metastatic small cell lung cancer, non-Hodgkin small cell lymphoma, retinoblastoma, medulloblastoma, nephroblastoma, small cell osteosarcoma, and round cell liposarcoma).

Two cases of discrete adenoid pseudogland formation within benign intradermal melanocytic nevi.

We report 2 cases of benign intradermal melanocytic nevi with discrete glandular elements and mucin deposition engendering a diagnostic dilemma. The preliminary differential included entrapment of adnexal structures, collision with an adnexal neoplasm such as adenoid cystic carcinoma or metastatic adenocarcinoma. A colloidal iron special stain confirmed the deposition of mucin; however, a pankeratin AE1/AE3 immunohistochemical cocktail was surprisingly negative.

Nuclear and cytoplasmic features in the diagnosis of Clark's nevi.

Background: Interpretation of Clark's nevi has generated debate over the years; although criteria have been proposed for grading morphological features of melanocytes, there is still confusion and variability in the assessment of these lesions.

Methods: This is a retrospective observational study conducted on 100 Clark's nevi and 84 melanomas. A single expert dermatopathologist evaluated all blinded and randomized photomicrographs of both the Clark's nevi and melanomas for the presence of 14 cytologic features.