People with acquired hypertrichosis lanuginosa have already lost their first embryonic hair fiber growth so strictly speaking it should not be described as lanugo hair but rather very long vellus hair. Acquired hypertrichosis lanuginosa has been reported as an advance symptom in many people later diagnosed with a malignancy of some form. Why a malignancy should promote hair growth is not known. Some dermatologists suggest some malignancies may involve disrupting hormone concentrations. Others suggest the malignancy may be producing its own hair growth stimulator, perhaps a cytokine.
Treatment involves targeting the original cause, the malignancy.
Successful removal of the malignancy removes the hair follicle stimulation and hair growth returns to normal. See other pages in this section for a more detailed look at acquired hypertrichosis lanuginosa in relation to cancer, inflammation, and injury with more extensive reference lists. Hypertrichosis lanuginosa acquisita. Clin Exp Dermatol. Goodfellow A, Calvert H, Bohn G. Hypertrichosis lanuginosa acquisita.