Based in the previous literature, we expected a cumulative incidence of recurrence in the control group of 27.6%. The study would require a sample size of 99 for each group (i.e. a total sample size of 198, assuming equal group sizes), to achieve a power of 80% for detecting a reduction in proportions of 0.15 between the two groups (reference group - intervention) at a two sided p-value of 0.05.