Collagen Anomalies as Clues for Diagnosis: Part 1.

Background: Collagen is the most abundant protein in the body and the main structural component of the skin.

Objective: To provide a review of the histopathology of collagen alterations and to propose a classification with the most important types of collagen anomalies in dermatopathology. The authors describe some of the main morphological clues of collagen anomalies for specific diagnosis of some cutaneous inflammatory and neoplastic conditions.

Congenital Atrophic Plaque: Fibroblastic Connective Tissue Nevus.

Fibroblastic connective tissue nevus (FCTN) is a rare, benign, dermal mesenchymal hamartoma that affects children. We report a 15-year-old boy with a congenital FCTN and describe the clinical, dermatoscopic, and histopathologic features.