A 59-year-old woman complains of skin lesion shown below catches on her clothing. It has been present for several years and is not associated with any other symptoms. What is the single most likely diagnosis?
**Core Concept**
The question is testing the student's knowledge of benign skin lesions, specifically a type of skin growth that is common in middle-aged adults and is characterized by its tendency to catch on clothing. This condition is a classic example of a benign skin lesion that can be easily mistaken for a more serious condition.
**Why the Correct Answer is Right**
The correct answer is likely a seborrheic keratosis, a type of benign skin growth that is common in middle-aged adults. Seborrheic keratoses are typically brown or black in color and have a warty or verrucous appearance. They are caused by the accumulation of keratinocytes, which are dead skin cells, and are often associated with sun exposure. The lesion in question is likely a seborrheic keratosis because it has been present for several years and is not associated with any other symptoms.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is likely a dermatofibroma, a type of benign skin growth that is caused by an injury to the skin. Dermatofibromas are typically smaller and more firm than seborrheic keratoses, and are often associated with a history of trauma.
* **Option B:** This option is likely a melanoma, a type of skin cancer. Melanomas are typically associated with changes in skin color, such as a new mole or a change in the size or shape of an existing mole, and are often accompanied by symptoms such as itching or bleeding.
* **Option C:** This option is likely a basal cell carcinoma, a type of skin cancer. Basal cell carcinomas are typically slow-growing and are often associated with sun exposure. However, they are usually smaller and more superficial than seborrheic keratoses.
**Clinical Pearl / High-Yield Fact**
Seborrheic keratoses can sometimes be mistaken for melanoma, but they are typically much more benign and can be easily distinguished by their warty or verrucous appearance and lack of associated symptoms.
**Correct Answer:** C.