A rapidly growing nodule on the face during pregnancy.

It is well known that adnexal skin tumors can simulate other cutaneous neoplasia and that various types of benign and malignant skin tumors can develop or modify during pregnancy. Here, we report a case of trichoblastoma mimicking a keratoacanthoma arising in a nevus sebaceous during pregnancy. Given its unique clinical and dermoscopic features, this case highlights the pivotal role of clinicopathological correlation in the diagnosis of adnexal tumors with an atypical clinical presentation.