# Is postmastectomy radiotherapy necessary for breast cancer patients with clinically node-positive downstaging to ypN0 after neoadjuvant chemotherapy?

**Autores:** Chen-Feng Tan, Jun Wang, Xiao-Rong Zhong et al.
**Revista:** Breast Cancer Res Treat (2024)
**PMID:** 38616207 | **PMCID:** —
**DOI:** [10.1007/s10549-024-07249-2](https://doi.org/10.1007/s10549-024-07249-2)
**Fuente:** PubMed (abstract only — full text vía DOI/institución)

## Relevancia
Estudio retrospectivo (n=333) que cuestiona la necesidad de PMRT en pacientes cN+ que convierten a ypN0 tras QT neoadyuvante. No detectan beneficio significativo en LRFS/DMFS/BCSS/OS con PMRT en este subgrupo a 5 años, alineándose con el ensayo NSABP B-51. Imprescindible para la sección de radioterapia post-NAC.

## Abstract
The significance of postmastectomy radiotherapy (PMRT) in breast cancer patients who initially have clinically node-positive (cN+) status but achieve downstaging to ypN0 following neoadjuvant chemotherapy (NAC) remains uncertain. This study aims to assess the impact of PMRT in this patient subset.

Patients were enrolled from West China Hospital, Sichuan University from 2008 to 2019. Overall survival (OS), Locoregional recurrence-free survival (LRFS), distant metastasis-free survival (DMFS), and breast cancer-specific survival (BCSS) were estimated using the Kaplan-Meier method and assessed with the log-rank test. The impact of PMRT was further analyzed by the Cox proportional hazards model. Propensity score matching (PSM) was performed to reduce the selection bias.

Of the 333 eligible patients, 189 (56.8%) received PMRT, and 144 (43.2%) did not. At a median follow-up period of 71 months, the five-year LRFS, DMFS, BCSS, and OS rates were 99.1%, 93.4%, 96.4%, and 94.3% for the entire cohort, respectively. Additionally, the 5-year LRFS, DMFS, BCSS, and OS rates were 98.9%, 93.8%, 96.7%, and 94.5% with PMRT and 99.2%, 91.3%, 94.9%, and 92.0% without PMRT, respectively (all p-values not statistically significant). After multivariate analysis, PMRT was not a significant risk factor for any of the endpoints. When further stratified by stage, PMRT did not show any survival benefit for patients with stage II-III diseases.

In the context of comprehensive treatments, PMRT might be exempted in ypN0 breast cancer patients. Further large-scale, randomized controlled studies are required to investigate the significance of PMRT in this patient subset.

## Acceso
Artículo no disponible en PMC. Acceder a través de [DOI](https://doi.org/10.1007/s10549-024-07249-2) o suscripción institucional.

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*Datos de PubMed. Citar: doi 10.1007/s10549-024-07249-2*
