Dermatology Practical & Conceptual

Yellow color upon dermatoscopy does not exclude melanoma!

…appearance, the differential diagnosis included an epidermal cyst or a sebaceous tumor. The dermatoscopic examination revealed mainly structureless yellow to pink areas and some dotted vessels. However, at the base and the periphery of the nodule, a…

Differential Diagnosis in Dermatopathology

Discussions

…dular, morpheiform, fibroepithelial tumorous, and infundibulo-cystic. Trichoepitheliomas and nodular basal-cell carcinomas are epithelial neoplasms with the following changes histopathologic in common: Dome-shape Aggregates of neoplastic trichoblast…

Differential Diagnosis in Dermatopathology

Apocrine mixed tumor vs. Eccrine mixed tumor

An inflammatory process that develops secondary to trauma, usually in the form of a penetrating injury or rupture of a follicle, and that proceeds through stages of granulation tissue with numerous extravasated erythrocytes, granulomatous inflammati…

Differential Diagnosis in Dermatopathology

Trichoepithelioma vs. Infundibulocystic basal-cell carcinoma

An inflammatory process that develops secondary to trauma, usually in the form of a penetrating injury or rupture of a follicle, and that proceeds through stages of granulation tissue with numerous extravasated erythrocytes, granulomatous inflammati…

Differential Diagnosis in Dermatopathology

Discussions

…rating one, but also consequent to rupture of an infundibular cyst. It evolves through stages of granulation tissue accompanied by countless extravasated erythrocytes, granulomatous inflammation, and fibrosis. At its zenith clinically, it is a papule…

Differential Diagnosis in Dermatopathology

Discussions

…times secondary to a ruptured infundibulum or an infundibular cyst. Therefore, the term dermatofibrosis describes the lesion more aptly, conveying as it does that the process is a type of fibrosing dermatitis, rather than a neoplasm of fibrocytes. Ma…

Histologic Diagnosis of Inflammatory Skin Diseases

Necrobiosis lipoidica

…at, as disparate as corneocytes (from a ruptured infundibular cyst) to urate (in some lesions of gout). It is easy for beginners in dermatopathology, and sometimes even for long-time practitioners, to misinterpret degeneration of collagen in necrobio…

Histologic Diagnosis of Inflammatory Skin Diseases

Lymphocytoma cutis

…gstanding inflammatory response to rupture of an infundibular cyst. Dilantin may induce changes in the skin that vaguely resemble those of a lymphoma, but that happens rarely. The designation, “lymphocytoma cutis,” and synonyms for it, la…