One of the most interesting and certainly the most unusual of the varieties of nevi is the so-called neuropathic papilloma, or naevus unius lateris. It is a papillary or verrucous congenital tumor having a unilateral or nearly unilateral distribution in linear streaks or bands following the long axis of the limbs or extending transversely around the trunk. This unique disease is so striking that it is readily recognized as a distinct clinicopathologic entity. Only 4 cases have been observed among 40,000 patients with tumors studied at the Memorial Hospital, an incidence of 0.01 per cent. To these have been added 156 cases from the literature, thus affording 160 cases for analysis.
The term naevus unius lateris was originated by von Baerensprung in 1863. Theories as to etiology, variations in appearance of the reported lesions and attempts to create names embodying both descriptive and pathogenetic elements have led to the