Basaloid Follicular Hamartoma Clinical Presentation

Updated: Aug 09, 2022
  • Author: Kara Melissa Torres Culala, MD; Chief Editor: Dirk M Elston, MD  more...
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Physical Examination

Hereditary basaloid follicular hamartoma

Lesions most often manifest on the face and scalp. The lesions also commonly develop diffusely on the skin of the neck, back, chest, and extremities. [9] Patients may have few to hundreds of lesions. Most commonly, they appear as 1- to 2-mm flesh-colored papules. However, hyperpigmented or hypopigmented lesions are not uncommon. [9, 20] Palmar pitting has been documented in some cases of hereditary basaloid follicular hamartoma. [9, 20, 41]

Additional clinical features associated with generalized basaloid follicular hamartoma syndrome (GBFHS), especially those with no systemic affection, include milia and comedonelike papules, [15] hypohidrosis, [22] alopecia or hypotrichosis, and dermatosis papulosa nigra–like growths. [9] Generalized basaloid follicular hamartoma syndrome has also been reportedly associated in a patient with acrochordons, seborrheic keratoses, and a history of chondrosarcoma. [11]

Linear unilateral basaloid follicular hamartoma (LUBFH) displays multiple flesh-colored to pigmented lesions in a linear, bandlike pattern running along the lines of Blaschko. [2, 50] In their early stages, the lesions may be hypopigmented, smooth, and striaelike. Lesional skin in an atypical case of linear unilateral basaloid follicular hamartoma was described as an atrophic, depressed patch. [42] A patient with linear unilateral basaloid follicular hamartoma with an unusual and extensive proliferation of trichoblastoma has also been reported. [51]

Acquired basaloid follicular hamartoma

The papules or plaques of basaloid follicular hamartoma are found on the eyelids, face, and scalp. [40, 52] The lesions may range from 0.1 cm to 3 cm. They may appear hypopigmented, hyperpigmented, or flesh colored. Hypotrichosis or alopecia may develop at sites of solitary basaloid follicular hamartoma. A case of a localized basaloid follicular hamartoma arising in an epithelioid blue nevus has been reported. [53]