Quantifying the Mitigating Effects of Whole-Breast Radiotherapy and Systemic Treatments on Regional Recurrence Incidence Among Breast Cancer Patients

Abstract

Background. Despite the potential for residual lymph node metastases after a negative or positive sentinel lymph node biopsy (SLNB), breast cancer patients rarely experience regional recurrences (RRs). This study aimed to quantify the effects of nonsurgical treatments on RR incidence among SLNB-negative (SLNB N0) breast cancer patients. Methods. All primary SLNB N0-staged breast cancer patients with a diagnosis between 2005 and 2008 and 5-year follow-up data on recurrences were selected from the Netherlands Cancer Registry. The cumulative incidence function (CIF) for RR was calculated as the first event at 5 years, taking into account any other first-event (local or distant recurrence, contralateral breast cancer, or death) as competing risk. Cox regression analysis was used to model the cause-specific hazard of RR developing as the first event to quantify the effect of adjuvant systemic therapy and whole-breast radiotherapy (RT) on RR incidence at 5 years. Results. The study included 13,512 patients. Of these patients, 162 experienced an RR. The CIF of RR at 5 years was 1.3% (95% confidence interval [CI], 1.1-1.5%), whereas the CIFs for death and other events were 4.4% and 9.5%, respectively. Cox regression analysis showed hazard ratios (HRs) of 0.46 (95% CI 0.33-0.64), 0.31 (95% CI 0.18-0.55), and 0.40 (95% CI 0.24-0.67) respectively for patients treated by RT as a routine part of breast-conserving therapy (BCT), chemotherapy, and hormonal therapy. Conclusion. RT as routine part of BCT, chemotherapy, and hormonal therapy independently exerted a mitigating effect on the risk for the development of RR. The three methods at least halved the risk.

ASO Author Reflections: Effect Sizes of Whole Breast Radiotherapy and Systemic Therapies on Regional Recurrence Incidence in Breast Cancer Patients

“…In the present study, we aimed to quantify the effects of whole-breast RT and systemic treatments on the RR incidence in a large-population-based cohort of SLN N0 breast cancer patients. 4 PRESENT In our study comprising 13,512 patients staged as N0 according to SLNB, the cumulative 5-year RR was 1.4%. 4 We demonstrated that RT, as a routine part of breastconserving therapy (BCT), chemotherapy, and hormonal therapy independently exerted a mitigating effect on the risk of developing RR with hazard ratios of 0.46, 0.31, and 0.40, respectively.…”

“…4 PRESENT In our study comprising 13,512 patients staged as N0 according to SLNB, the cumulative 5-year RR was 1.4%. 4 We demonstrated that RT, as a routine part of breastconserving therapy (BCT), chemotherapy, and hormonal therapy independently exerted a mitigating effect on the risk of developing RR with hazard ratios of 0.46, 0.31, and 0.40, respectively. None of these treatments had been given with the intent to reduce risk of developing RR.…”

Predicting HER2 Status in Breast Cancer on Ultrasound Images Using Deep Learning Method

“…The quantitative effectiveness is shown in Table 2, and the ROC curves are shown in Figure 5, which suggested that our HER2 is a critical biomarker and its expression helps to make personalized treatments for breast cancer patients. Patients whose HER2 is positive should receive trastuzumab (marketed as Herceptin) which is effective only in cancers where HER2 is overexpressed (38). In clinical practice, IHC is widely used to evaluate the expression of HER2.…”

mu-Opioid Receptor Polymorphisms and Breast Cancer Recurrence in Adult Korean Women Undergoing Breast Cancer Surgery: A Retrospective Study

“…Data regarding pathological findings, cancer stage, anaesthetic technique during surgery, and postoperative cancer treatment were reviewed. Information regarding breast cancer recurrence within 5 years (from June 2012 to June 2019) was acquired from the medical records, and cases with tumour recurrence were classified into different categories, as previously described 9 . Local recurrence was defined as tumour recurrence in the breast where the cancer was originally diagnosed, or in the skin or subcutaneous tissue of the ipsilateral chest wall.…”