Differential Diagnosis for Hard Round Nodule on Forehead
Single Most Likely Diagnosis
- Sebaceous cyst: A common, benign skin growth that can present as a hard, round nodule, often found on the forehead. It is usually non-tender and can be movable.
Other Likely Diagnoses
- Epidermoid cyst: Similar to sebaceous cysts, epidermoid cysts are benign growths that can appear as hard, round nodules on the forehead. They are generally non-tender.
- Dermatofibroma: A benign skin growth that can feel like a hard, round nodule, often resulting from minor injury, most commonly found on the legs but can occur on the forehead.
- Lipoma: A benign tumor composed of fat tissue, which can present as a hard, round nodule if it is deep enough, though they are more commonly soft.
Do Not Miss Diagnoses
- Basal cell carcinoma: Although less likely, basal cell carcinoma is a type of skin cancer that can present as a hard, round nodule. It is crucial to consider this diagnosis due to its potential for local destruction if left untreated.
- Squamous cell carcinoma: Another form of skin cancer that can appear as a hard nodule, especially in sun-exposed areas like the forehead.
Rare Diagnoses
- Metastatic tumor: Rarely, a hard, round nodule on the forehead could be a metastasis from another cancer, such as breast, lung, or melanoma, though this would be extremely uncommon.
- Cylindroma: A rare, benign tumor of the skin adnexa that can present as a firm, round nodule, often on the scalp or forehead.
- Trichoepithelioma: A rare, benign skin tumor that originates from hair follicles and can appear as a hard, round nodule on the face, including the forehead.