Fine needle aspiration cytology of a sebaceous lymphadenoma: a case report.

Background: Sebaceous lymphadenoma is a rare, benign neoplasm, histologically characterized by proliferating islands of epithelium with sebaceous glandular differentiation in a dense, lymphocytic background. The parotid gland is the most common site, and the patient usually presents with a well-circumscribed, enlarging and painless mass. Primary sebaceous lesions of the salivary glands are very rare entities and must be differentiated from more common, potentially malignant tumors.

Mesenchymal chondrosarcoma: molecular characterization by a proteomic approach, with morphogenic and therapeutic implications.

This study characterizes 3 cases of mesenchymal chondrosarcoma (MC) utilizing a proteomic approach that allows for the detection, visual quantification, cellular compartmentalization, and assessment of the functional state of certain proteins that may promote tumor growth and/or oppose apoptosis. Immunohistochemical procedures were performed to detect the following protein antigens: CD99, interleukin (IL)-1alpha, IL-6, transforming growth factor (TGF)-alpha, conventional (c) protein kinase C (cPKC)-alpha, cPKC-betaII, phosphorylated (p)-PKC-alpha/betaII, c-kit (CD117), platelet-derived growth factor receptor (PDGFR)-alpha, PDGFR-beta, epidermal growth factor receptor (EGFR), human epidermal growth factor receptor (HER)-2/neu, cathepsin D, angiotensin-converting enzyme (ACE), angiotensin II type 1 (AT1) receptor, p21ras, the alpha subunit of farnesyl and geranylgeranyl transferase (FTalpha/GGTalpha), phospho (p)-c-Jun N-terminal kinase (p-JNK), p-p38 mitogen-activated protein kinase (MAPK), cyclin D1, c-Jun, Ki-67, bcl-2, TGF-beta1 latency-associated peptide (LAP), TGF-betaRII, and cyclooxygenase (COX)-2. Immunoreactivities were scored from 0 to 3+ positivity using bright-field microscopy.

Tyrosinase expression in malignant melanoma, desmoplastic melanoma, and peripheral nerve tumors.

Context: Pathologists may encounter problems in the differential diagnosis of malignant melanoma, spindle and epithelioid neoplasms of peripheral nerves, and fibrohistiocytic tumors. Tyrosinase has been demonstrated to be a sensitive marker for melanoma.

Objective: To determine the specificity of tyrosinase expression in the differential diagnosis of melanoma, desmoplastic melanoma, and peripheral nerve sheath tumors.