Fig. 4

Distant metastasis dynamics following surgery for IBTR, contralateral breast tumour and reconstruction (t = 0 at second surgery). The hazard rate pattern is similar for the three groups with a first major peak at about 24 months and a second lower one at about 5 years. The analysis was performed for all patients (bold lines) and, moreover, by time from primary tumour removal to second surgery as well (dashed lines). While this factor is not influent for reconstructed patients, it changes the first peak height for surgeries removing neoplastic nodules if the time to second surgery is less than about 3 years. Confidence intervals on the estimated hazard rates at the first peak position are reported for all patients and those with time to second surgery more than 48. Y-axis reports hazard rates for DM, i.e. the conditional probability of manifesting DM during an interval of 6 months, given that the patient is clinically DM free at the beginning of the interval. X-axis units are months between primary tumour removal and the second surgical manoeuvre