Differential Diagnosis for a Flat, Rough, and Wart-like Spot on the Cheek Close to the Ear
- Single Most Likely Diagnosis
- Seborrheic keratosis: This is a common, benign skin growth that can appear as a flat, rough, and wart-like spot, often in older adults. Its location on the cheek, close to the ear, is consistent with areas typically exposed to the sun, which can contribute to the development of seborrheic keratoses.
- Other Likely Diagnoses
- Actinic keratosis: This is a precursor to skin cancer and appears as a rough, scaly patch on areas of skin that have had prolonged exposure to the sun. The location near the ear makes it plausible due to sun exposure.
- Squamous cell carcinoma (SCC): Although less common than actinic keratosis, SCC can present as a firm, rough, or wart-like lesion, especially in sun-exposed areas.
- Basal cell carcinoma (BCC): The most common form of skin cancer, BCC can appear as a flat, rough lesion, though it's more commonly associated with a pearly or translucent appearance.
- Do Not Miss Diagnoses
- Melanoma: Although less likely, melanoma is the most dangerous form of skin cancer and can present in various ways, including as a new or changing mole. Any pigmented lesion, especially one that is asymmetric, has irregular borders, color variation, a diameter larger than 6mm, or is evolving, should be considered for biopsy to rule out melanoma.
- Merkel cell carcinoma: A rare but aggressive skin cancer that can appear as a firm, painless nodule or bump, often in sun-exposed areas.
- Rare Diagnoses
- Dermatofibroma: A benign skin growth that can appear as a firm, rough bump, often resulting from minor injury, but less commonly found on the face.
- Keratoacanthoma: A low-grade, or sometimes considered benign, malignancy that resembles a volcano-shaped nodule, which can resolve on its own but may need to be differentiated from SCC.
- Cutaneous lymphoma: A rare form of lymphoma that affects the skin, which can present in various forms, including as plaques, patches, or nodules.
Each of these diagnoses has distinct characteristics, and a definitive diagnosis often requires a clinical examination and possibly a biopsy. The justification for each is based on the typical presentation and common locations of these skin conditions.