Perform the following step:

> survdiff(Surv(cancer$time, cancer$status)~cancer$sex)
 Output
    Call:
    survdiff(formula = Surv(cancer$time, cancer$status) ~ cancer$sex)
    N Observed Expected (O-E)^2/E (O-E)^2/V
    cancer$sex=1 138 112 91.5817 4.55228 10.3267
    cancer$sex=2 90 53 73.4183 5.67850 10.3267
    Chisq= 10.3 on 1 degrees of freedom, p= 0.00131116