All cases of primary pleural cancers that were reported during a 10-y period (i.e., 1978-1987) in New Caledonia were recorded and compared with five cancer registers. There was an excess of primary pleural cancers in the area of New Caledonia, and it was particularly evident among the Melanesian ethnic group. Neither geographical nor occupational factors accounted for these results, but an environmental factor could not be excluded.