Histologic Diagnosis of Inflammatory Skin Diseases

Topography and Regional Variation

The skin of infants is traversed by a subtle maze of ridges that develops during the fourth and fifth months of fetal life. The ridges become increasingly prominent during childhood. Those surface markings remain stable throughout life and are nearl…

Histologic Diagnosis of Inflammatory Skin Diseases

Muscles

In the skin, smooth muscle occurs in two different unrelated settings. One is in fascicles that form muscles of hair erection and the other is in the wall of arterioles and venules. The fascicles that make up the arrector pili muscle originate from…

Histologic Diagnosis of Inflammatory Skin Diseases

Applicable Terms

ABSCESS [L. abscessus (a going away)]: Clinically, a circumscribed collection of pus and histopathologically a localized collection of neutrophils. An abscess may form in the epidermis, both surface and infundibular, eccrine ducts, dermis, and subcu…

Histologic Diagnosis of Inflammatory Skin Diseases

Hair Follicles

Morphologic and qualitative differences in hair, a cornified end-product of matrical cells positioned in the center of a follicular bulb, exist among the races of Man. In general, Caucasians have the most prominent hair, Asians have the least, and A…

Resolving Quandaries in Dermatology, Pathology & Dermatopathology

Pseudomalignancies?

“The term pseudocancerosis covers a variety of diseases that can be difficult to distinguish from true carcinomas not only clinically but also histologically. However, pseudocanceroses may not only be similar to squamous cell carcinomas but a…

Resolving Quandaries in Dermatology, Pathology & Dermatopathology

Origin of Adnexal Neoplasms?

“Thus one needs to bear in mind the information required of a pathologist about a particular tumour, which can be summarized as follows: 1. What is the origin of the tumour? 2. What is likely the behavior of the tumour? 3. What is the extent…

Resolving Quandaries in Dermatology, Pathology & Dermatopathology

Breast a Sweat Gland?

“The breast is a modified sweat gland covered by skin and subcutaneous tissue.” Rosai J. The breast. In: Ackerman’s Surgical Pathology. 7th ed. St. Louis, MO: CV Mosby, 1989:1193. “The mammary glands are modified swat gla…

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…

Resolving Quandaries in Dermatology, Pathology & Dermatopathology

Dermal Papilla?

“Historically, the hair germ has been defined as a group of cells located at the base of the telogen follicle in close contact with the dermal papilla.” Lavker RM, Miller S, Wilson C, et al. Hair follicle stem cells: their location, ro…