AAFM Boards Dermatology Practice Test 2025 - Free Dermatology Practice Questions and Study Guide

Epidermal cysts, also known as epidermoid cysts, are benign, slow-growing tumors that originate from the epidermis or hair follicle. One notable characteristic of these cysts is the presence of a central punctum. This central opening often marks the cyst's connection to the skin surface and may sometimes be seen as a small black dot. The punctum can become obstructed, leading to the accumulation of keratin and other cellular debris within the cyst, contributing to its typical appearance.

Several important aspects related to the other options help contextualize why the statement about the central punctum is accurate. While it is common for these cysts to be filled with keratin rather than sebum, they do not always resolve spontaneously. Many epidermal cysts persist for long periods without intervention and usually do not require immediate surgical removal, as they are benign and asymptomatic. Surgical intervention is typically only necessary if the cyst becomes infected or is symptomatic, meaning that immediate surgical intervention is not a requirement for every case.