Dermatology Practical & Conceptual

Pigmented poroma with unusual location and dermatoscopic features

Abstract Poroma is a benign adnexal neoplasm with “poroid”/ductal differentiation that mimics benign and malignant skin tumors. Histopathology shows circumscribed proliferation of poroid cells intermingled with a variable number of cutic…

Dermatology Practical & Conceptual

The dermatoscopic universe of basal cell carcinoma

Abstract Following the first descriptions of the dermatoscopic pattern of basal cell carcinoma (BCC) that go back to the very early years of dermatoscopy, the list of dermatoscopic criteria associated with BCC has been several times updated and rene…

Histologic Diagnosis of Inflammatory Skin Diseases

Granuloma annulare

Granuloma annulare Presentation stereotypical Age and sex Any age in both sexes Distribution of lesions Localized, often to extensor aspects of extremities, or widespread Configuration of lesions Annular, sometimes arcuate Arrangement of lesions Sca…

Differential Diagnosis in Dermatopathology

Trichoblastoma, small nodular type vs. Trichoblastoma, large nodular type

A malignant neoplasm made up of abnormal germinative cells analogous to those that compose the folliculosebaceous-apocrine germ in an embryo and that usually manifests clinically as a papule or nodule which may become ulcerated. On the basis of clin…

Resolving Quandaries in Dermatology, Pathology & Dermatopathology


“Cutaneous fibroma Fibroma simplex Simple fibroma of the skin, as defined above, is a benign tumor, usually appearing solitary, on the upper part of the body and the extremities, which, mainly imbedded in the skin, is only rarely and little…

Resolving Quandaries in Dermatology, Pathology & Dermatopathology

Cutaneous Horn?

“Cutaneous horns may complicate solar keratoses, viral warts, seborrheic warts, squamous cell carcinomas, lichenoid keratoses, and basal cell carcinomas.” McKee PH. Tumors of the surface epithelium. In: Pathology of the Skin with Clinic…

Differential Diagnosis in Dermatopathology


Dermatofibroma, hemorrhagic papulo-nodule Kaposi’s sarcoma, hemorrhagic papulo-nodule

Differential Diagnosis in Dermatopathology

Differential Diagnosis

Dermatofibroma, hemorrhagic papulo-nodule Kaposi’s sarcoma, hemorrhagic papulo-nodule 1. Poorly circumscribed; border sometimes jagged 1. Well-circumscribed; border smooth 2. Epidermis acanthotic and hyperpigmented 2. Epidermis thinned a…