[Cutaneous malignant melanoma in New Caledonia (South Pacific) 1973-1991. A study of 97 cases]

The Cancer Registries have been operational in the South Pacific since 1958 (Papua New Guinea), Fiji (1965) and New Caledonia (1977) and complete cancer incidence rates are available, based on histologic data. We studied 97 melanomas, histologically confirmed, which were diagnosed in New Caledonia from 1973 to 1991. New Caledonia is located in the same latitude as Queensland in Australia, known for having the highest incidence of melanoma in the world. Standardised incidence rates (world population) were 9.82 and 7.65/100,000/year for European males and females, compared to 1.65 and 1.05 for Melanesian and Polynesian males and females. The European population is exposed and Melanesians/Polynesians are relatively protected as are black Americans or Africans. The mixed populations are protected, but no study is available as to the exact proportion of mixed people (20%?) in the entire population. For Europeans, among males, the main areas in which melanomas occur are the trunk (45%) the arm (13%) and the leg (13%). Among females, the main areas are the leg (27%), the trunk (20%) and the head (18%). Screening for melanoma has been more effective in the last 6 years, a period in which we diagnosed half the total cases and generally at earlier stages. Prognosis was poor for this period (1973-1991): the five year survival rates were 64% +/- 8%, not as good as in Europe or Australia, but these lesions were diagnosed between 1973 and 1985 and were generally more invasive. A better prognosis will probably be observed in a few years, and another evaluation of melanoma screening should be made in the future as well the study of precursors and early lesions.