Prognostic validation and therapeutic decision‐making of the AJCC eighth pathological prognostic staging for T3N0 breast cancer after mastectomy

Abstract

Background T3N0 breast cancer might be a distinct clinical and biological entity, with higher heterogeneity and presenting diverse responses to locoregional and systemic therapy. The aim of the current study was to validate the prognostic effect and assess the treatment decision‐making of the American Joint Committee on Cancer (AJCC) eighth pathological prognostic staging in T3N0 breast cancer after mastectomy. Methods We retrospectively included 2465 patients with stage T3N0 breast cancer who had undergone mastectomy between 2010 and 2014 using the data from Surveillance, Epidemiology, and End Results program. The primary endpoint of this study was breast cancer–specific survival (BCSS). Results Of the entire cohort, 76.0% of patients in the seventh AJCC staging system were restaged to the eighth AJCC pathological prognostic staging system. A total of 1431 (58.1%) and 1175 (47.7%) of them received chemotherapy and postmastectomy radiotherapy (PMRT), respectively. Pathological staging was an independent prognostic factor for BCSS. Using pathological prognostic stage IA as the reference, BCSS gradually became worse with increased hazard ratios. The 5‐years BCSS was 96.9%, 95.5%, 91.1%, 85.6%, and 75.5% in pathological prognostic stage IA, IB, IIA, IIB, and IIIA breast cancers, respectively (P < .001). In pathological prognostic stage IA, IB, and IIA breast cancers, the receipt of PMRT or chemotherapy was not correlated with better BCSS. However, PMRT was correlated with better BCSS in pathological prognostic stage IIB disease (P = .006), but not in pathological prognostic IIIA disease. Moreover, chemotherapy was correlated with better BCSS in pathological prognostic stage IIIA disease (P = .006), but not in pathological prognostic stage IIB disease. Conclusions The eighth AJCC pathological prognostic staging system provides more risk stratification of T3N0 breast cancers after mastectomy and might affect individualized decision‐making for chemotherapy and PMRT in this patient subset.

Triple-negative breast cancer outcomes: Does AJCC 8th staging improve chemotherapy decision-making

“…Regarding the treatment decision for chemotherapy, we also found that patients with T1-2N1M0 disease could obtain survival benefit from chemotherapy irrespective of the pathological prognostic stages [30]. Moreover, our previous study also observed a survival gain from chemotherapy in T3N0M0 BC patients with 8th AJCC stage IIIA disease but was not in those with stage IA, IB, and IIA diseases [31]. To the best of our knowledge, no studies investigated the effect of chemotherapy in T1-2N0M0 TNBC based on the 8th prognostic staging of AJCC.…”

“…As mentioned above, many studies have fully explored the prognostic value of the new AJCC prognostic staging, but its guiding role in treatment decision-making is still not clear. Our previous studies had shown that the new AJCC staging might provide additional treatment decisions, including surgery and radiotherapy [17,30,31]. Regarding the treatment decision for chemotherapy, we also found that patients with T1-2N1M0 disease could obtain survival benefit from chemotherapy irrespective of the pathological prognostic stages [30].…”

Clinical and Biological Characteristics of T3n0m0 and T4n0m0 Breast Cancer

“…В исследовании китайских ученых Wu S. et al [12] пациенткам с T3N0M0 РМЖ, стадированным по классификации TNM 7 версии, установили новые прогностические стадии согласно TNM 8 версии. С увеличением прогностической стадии снижалась ОСВ пациенток.…”

Impact of AJCC prognostic staging on prognosis and postmastectomy radiotherapy decision-making in hormone receptor-positive and HER2-positive breast cancer

“…A valuable staging system should also provide effective guidance for selection of appropriate treatment. Previous studies have found that the new PPS may have an important role in treatment decision-making for stage I to III BC 10 , 11 . However, a recent study showed that PPS did not provide better discriminatory ability of risk stratification compared with the AS in T1-2N0M0 triple-negative BC, but PPS could more accurately predict the efficacy of chemotherapy 12 .…”