ABSTRACT
We report a case of an aggressive digital papillary adenocarcinoma (ADPA) on the right thumb of a 48-year-old white man. Histologic evaluation of the initial biopsy demonstrated features consistent with those proposed for aggressive digital papillary adenoma; however, re-excision of the remaining lesion revealed histologic features consistent with aggressive digital papillary adenocarcinoma. These tumors have a high rate of local recurrence and can metastasize, occasionally resulting in mortality. Our case demonstrates that even if the histologic criteria of aggressive digital papillary adenocarcinoma are met, the lesion may still represent an aggressive digital papillary adenocarcinoma (ADPAca). In agreement with a recent study by Duke et al., this case supports the idea that aggressive digital papillary lesions should be classified as aggressive digital papillary adenocarcinoma.
Subject(s)
Adenocarcinoma, Papillary/pathology , Sweat Gland Neoplasms/pathology , Adenocarcinoma, Papillary/chemistry , Adenocarcinoma, Papillary/surgery , Adenoma/diagnosis , Carcinoembryonic Antigen/analysis , Diagnosis, Differential , Humans , Immunohistochemistry , Keratins/analysis , Male , Middle Aged , S100 Proteins/analysis , Sweat Gland Neoplasms/chemistry , Sweat Gland Neoplasms/surgery , Thumb/pathologyABSTRACT
Trichoepitheliomas and many basal cell carcinomas appear to arise from the hair follicle, and in particular from the hair follicle bulge. This histogenesis is suggested from both morphological and immunohistochemical studies on tumor cells and stroma. Epithelial stem cells are thought to be important in tumorigenesis, and we previously localized a population of stem cells to the bulge area of the outer root sheath. We recently identified an anti-CD8 monoclonal antibody (DAKO clone C8/144B) that cross-reacts with cytokeratin 15 (K15), and serves as a specific marker for the bulge. In this study, we screened a series of trichoepitheliomas (n=13), basal cell carcinomas (n=37) and a variety of other skin tumors with this antibody. All trichoepitheliomas (100%) showed keratin 15 expression, while only a subset of basal cell carcinomas (27%) was K15-positive. Epidermal tumors, including squamous cell carcinomas, were K15-negative. Tumors of follicular derivation such as proliferating trichilemmal cysts were also K15-positive, while others such as pilomatricoma were K15-negative. Expression of K15 in trichoepitheliomas, some basal cell carcinomas and other follicular tumors suggests that these tumors are related to hair follicle stem cells in the bulge.
Subject(s)
Carcinoma, Basal Cell/metabolism , Hair Follicle/metabolism , Keratins/metabolism , Skin Neoplasms/metabolism , Stem Cells/metabolism , Antibodies, Monoclonal/immunology , Biomarkers, Tumor , Carcinoma, Basal Cell/pathology , Hair Follicle/pathology , Humans , Immunoenzyme Techniques , Keratin-15 , Neoplasms, Basal Cell/metabolism , Neoplasms, Basal Cell/pathology , Skin Neoplasms/pathology , Stem Cells/pathologyABSTRACT
Low dose methotrexate (MTX) can cause numerous gastrointestinal, pulmonary, central nervous system, and hematologic toxicities. Risk factors include folate deficiency, decreased renal function, older age, increased mean corpuscular volume or concomitant use of trimethoprim-sulphamethoxazole, probenecid, or nonsteroidal antiinflammatory drugs (NSAIDs). We describe a case of isolated thrombocytopenia after a single oral dose of MTX in a 36-year-old woman with sarcoidosis. She had rheumatoid arthritis and her only other medications included NSAIDs. One week after her first oral dose of 7.5 mg MTX, diffuse petechiae developed on her chest, abdomen, and extremities; she had a platelet count of 25,000/mm3. Nine days after discontinuation of both MTX and the NSAID, her platelet count increased to 189,000/mm3.
