[Significance of the intraductal component in local recurrence after breast-conserving surgery]

Several predictors of local recurrence (LR) after breast conservation in early stage (stage I and II) breast cancer have been reported in the literature, but the importance of the individual factors does not appear to be clear. The presence of intraductal component (IC) is one of those factors; some authors regard it to be a predictor of LR, while others do not, or the latter have found a relationship with LR only if IC and certain other factors were present simultaneously. The authors investigated the impact of the presence of IC of various degrees on LR rate in various tumour sizes and degrees of histological anaplasia. Between 1996 and 2002, 701 patients with early stage breast cancer underwent breast conserving surgery. Based on the presence of IC, the tumours were divided into three groups: IC negative, MIC (IC < 25%) and EIC (IC > 25%). During the 65-month mean follow-up period, LR was discovered in 13.5% of the patients. Local recurrence in tumours without IC was found in 8.7% (recurrence rate: 0.017, 95% CI: 0.012-0.012). The relevant figures in MIC and EIC were 16.8% (recurrence rate 0.032, 95% CI: 0.021-0.047) and 25.6% (recurrence rate: 0.046, 95% CI: 0.033-0.064), respectively (p = 0.0001). If the size of the tumour was T1, the above figures were found to be 6.4%, 11% and 24.3%, while in size T2 tumours they were 11.5%, 22.9% and 27% (p < 0.005). If EIC was associated with G3 degree of differentiation, in IC-free tumours of size T1, the LR rate elevated from 6.1% to 31% (p = 0.008), while in size T2 the elevation was from 15.7% to 33.% (p = 0.02). Based on the above results, the authors concluded that the presence of the intraductal component predicts a greater risk to develop LR. This risk increases significantly if EIC is associated with G3 histological grade. Physicians must consider this fact in designing individually tailored adjuvant therapy for their patients. Special attention should also be paid to the follow-up of this group of patients.