Figure 4

Kaplan-Meier survival curves of patients divided in 5-years periods according to the date of diagnosis: 1 = 1974–1979 (n = 46); 2 = 1980–1984 (n = 94); 3 = 1985–1989 (n = 67); 4 = 1990–1994 (n = 76); 5 = 1995–1999 (n = 88); 6 = 2000–2002 (n = 55). Statistically significant improvement of survival was shown in periods 5 (1995–99) and 6 (2000–02) when compared with period 4 (1990–94) (p = 0.0006). No differences were observed between survival of patients in period 4 (1990–94) and periods previous to year 1990.