Lichen planus pemphigoides and multiple keratoacanthomas associated with colon adenocarcinoma

Sir, Lichen planus pemphigoides (LPP) is a rare skin disorder characterized by a mixture of clinical, histological and immunological features of both lichen planus (LP) and bullous pemphigoid (BP). Most cases of LPP have been reported as an idiopathic mucocutaneous disease. However, some cases of LPP have been reported to be in association with neoplasia, and to share the characteristics of paraneoplastic pemphigus (PNP).1–5 A 70‐year‐old man presented with a 6‐month history of pruritic eruption on the trunk and extremities, and suffered from progressive sore throat, oral pain and general fatigue. Four months earlier, he had developed four discrete dome‐shaped nodules with a hyperkeratotic surface on the back and arm. No family members had had colon carcinoma or multiple keratoacanthomas (KAs). Physical examination revealed numerous papules up to 1 cm in diameter on the trunk and extremities, the features of which resembled insect bites or prurigo (Fig. 1a). Numerous keratotic papules up to 5 mm in diameter were observed on the dorsal hands. Oral lesions included painful erosions on the tongue, lace‐like white streaks on the buccal mucosa and a violaceous macule on the lips (Fig. 1b). The conjunctivae and genitalia were not involved.