Some factors are related: age over 40 years old is higher than that of group under 40 years old, in which group 40 - 60 is OR = 4.85 (95% CI: 1.16 - 20.30); >60 is OR = 13.50 (95% CI: 1.31 - 138.62); stage IV (compared to stage I-II) OR = 10.94 (95% CI: 1.18 - 101.42); hair loss OR = 7.56 (95% CI: 1.58 - 36.29); have side effects on nerves OR = 6.09 (95% CI: 1.55 - 23.95).