Synchronous multiple primary malignant melanoma in a patient with atypical mole syndrome

Abstract

CASE PRESENTATIONThe case of a 48-year-old man is presented. He has lived in the United Kingdom all his life except for annual family holidays abroad. The patient has Fitzpatrick type II skin and had no previous personal or family history of melanoma. However, he described himself and his two daughters as having "a large number of moles."The patient presented to his family doctor in January 1999 with a history of a changing mole on his right hypochondrium. It was getting bigger and darker. This mole, like several others, mainly on his trunk, had been present for several years. He was referred to and seen urgently in the dermatology department where an urgent excision biopsy was carried out. The histology confirmed a superficial spreading malignant melanoma with Breslow thickness of 2.2 mm. He was then referred to the plastic surgery department for further care.He was seen at the plastic surgery clinic within one week of the histological diagnosis and within three weeks of his presentation to his family doctor. At his first visit, he was found to have more than 100 naevi of varying sizes that were mainly on his trunk. Five of these naevi were dysplastic or early melanoma (Figures 1-5). He had no palpable peripheral lymph nodes. A directed lymph node biopsy, using preoperative technetium 99 colloid lymphoscintigraphy, intraoperative dye injection and hand-held gamma probe, was carried out as part of the management of his right hypochondrial melanoma. The dynamic image of the lymphoscintigram (Figure 6) showed simultaneous drainage to both axillae only. Figure 7 showed the sentinel nodes. The five suspicious lesions (Figures 1-5) were biopsied at the same time. The sentinel node from the right axilla was positive, and a formal block dissection was carried out; the node from the left axilla was negative. Further primary malignant melanoma was confirmed on the right shoulder (Breslow thickness on the right shoulder of Multiple primary malignant melanoma developing in people with atypical mole syndrome is well documented but rare. Synchronous occurrence of such melanomas is even rarer. The present case report, while not unique, provides an excellent opportunity to remind clinicians of presentation and management of atypical mole syndrome, while emphasizing the higher risk of developing malignant melanoma. Key Words: Atypical mole syndrome; Synchronous multiple primary malignant melanomaApparition d'un mélanome malin primitif multiple synchrone chez un patient atteint du syndrome atypique de naevi RÉSUMÉ : L'apparition d'un mélanome malin primitif multiple chez les personnes atteintes du syndrome atypique de naevi est bien documentée mais rare. Toutefois, l'apparition synchrone de plusieurs mélanomes est encore plus rare. Voici un exposé de cas, non unique d'ailleurs, qui rappelle aux cliniciens non seulement la présentation et le traitement du syndrome atypique de naevi, mais aussi les risques accrus de mélanome malin qui lui sont associés.