Paraneoplastic hypertrichosis lanuginosa acquisita: uncommon or overlooked?

Acquired hypertrichosis lanugo-type or hypertrichosis lanuginosa acquisita (HLA) is often associated with metabolic and endocrine disorders and use of certain drugs. The occurrence of HLA with malignancy was first noted in 1865, and it has since been described in 56 patients as a paraneoplastic syndrome both in women and in men. Sometimes HLA occurs concurrent with acanthosis nigricans, papillary hypertrophy of the tongue, and glossitis. The predominance of female cases is striking. Malignancy-associated HLA seems to occur especially in the age group 40-70 years. In women with HLA the most frequent malignancy is colorectal cancer, followed in order by lung cancer and breast cancer; in men lung cancer is the malignancy most frequently associated with HLA, followed by colorectal cancer. In 3 years we saw 10 patients with HLA, in whom the malignancy was usually metastasized. Only one patient had local disease; after removal of the primary tumour it took 2 years before the lanugo hair recurred. The aetiology of the syndrome is not clear: no specific hormonal or biochemical abnormalities have been identified as yet. The difference between hirsutism and lanugo-type hypertrichosis is discussed. It is stressed that the appearance of lanugo-type hypertrichosis in body areas previously perceived by patients as 'hairless' is highly indicative of internal malignancy.