Tumor of follicular infundibulum (TFI), also known as infundibuloma, is a benign cutaneous adnexal tumor. This typically presents as a solitary, smooth or keratotic papule on the head, neck, or trunk. It has also been described in case reports to occur on the extremities and vulva. Multiple TFIs is a rare clinical variant and classically presents as symmetrically distributed, hypopigmented macules or depressed papules. Multiple lesions usually range in number from 10-20. The term "eruptive infundibulomatosis" indicates hundreds of tumors. The lesions are asymptomatic but can be associated with pruritus secondary to sun exposure.

TFI usually occurs in elderly individuals. Its incidence is estimated to range between 3-20 cases per 100 000 skin biopsies. Epidemiological reports comparing rates between males and females have been inconsistent.

While the etiology of TFI is not completely understood, some describe its origin from follicular infundibulum, whereas other studies state that the name is a misnomer, as the tumor cells resemble isthmic differentiation. TFI has been described to coexist with other cutaneous lesions (both seen within the same biopsy specimen), including basal cell carcinoma (BCC), squamous cell carcinoma (SCC), actinic keratosis, epidermal cysts, nevus sebaceus, malignant melanoma, and nevi. It is therefore also postulated that TFI lesions could represent an epidermal reactive process to the presence of the adjacent tumor.