T1-2N1M0 triple-negative breast cancer patients from the SEER database showed potential benefit from post-mastectomy radiotherapy

Development and validation of survival nomograms in elder triple-negative invasive ductal breast carcinoma patients

BACKGROUND

We aimed to develop a nomogram to predict the overall survival of elderly patients with Triple-negative invasive ductal breast carcinoma (TNIDC).

RESEARCH DESIGN AND METHODS

12165 elderly patients with nonmetastatic TNIDC were retrieved from the SEER database from 2010 to 2019 and were randomly assigned to training and validation cohorts. Stepwise Cox regression analysis was used to select variables for the nomogram based on the training cohort. Univariate and multivariate Cox analyses were used to calculate the correlation between variables and prognosis of the patients. Survival analysis was performed for high- and low-risk subgroups based on risk score.

RESULTS

Eleven predictive factors were identified to construct our nomograms. Compared with the TNM stage, the discrimination of the nomogram revealed good prognostic accuracy and clinical applicability as indicated by C-index values of 0.741 (95% CI 0.728-0.754) against 0.708 (95% CI 0.694-0.721) and 0.765 (95% CI 0.747-0.783) against 0.725 (95% CI 0.705-0.744) for the training and validation cohorts, respectively. Differences in OS were also observed between the high- and low-risk groups (p < 0.001).

CONCLUSION

The proposed nomogram provides a convenient and reliable tool for individual evaluations for elderly patients with M0_stage TNIDC. However, the model may only for Americans.

Effect of postmastectomy radiotherapy on T1-2N1M0 triple-negative breast cancer

Background

The effect of postmastectomy radiotherapy (PMRT) on T1-2N1M0 triple-negative breast cancers (TNBC) remains unclear. The population-based study aimed to investigate the survival outcomes of T1-2N1M0 TNBC patients who underwent PMRT or not.

Methods

We selected 1743 patients with T1-2N1M0 TNBC who underwent mastectomy between 2010 and 2015 through the Surveillance, Epidemiology and End Results (SEER) database. After propensity score matching (PSM), the PMRT and no-PMRT groups consisted of 586 matched patients, respectively. The Kaplan-Meier method was applied to calculate breast cancer-specific survival (BCSS) and cox proportional hazard model was used to determine the prognostic factors of T1-2N1M0 TNBC.

Results

The 5-year BCSS for the PMRT and no-PMRT groups was 79.1% and 74.7%, respectively. Analysis showed that in patients with three nodes positive, radiotherapy could significantly improve BCSS (HR = 0.396, 95% CI = 0.175–0.900, P = 0.027), but it brought no significant advantage in BCSS in patients with one or two nodes positive (HR = 1.061, 95% CI = 0.725–1.552, P = 0.761; HR = 0.657, 95% CI = 0.405–1.065, P = 0.088). In addition, PMRT improves the BCSS in TNBC patients with T2 tumor concomitant with three positive lymph nodes (HR = 0.343, 95% CI = 0.132–0.890, P = 0.028).

Conclusion

TNBC patients with T2 tumor concomitant with three positive lymph nodes can benefit from PMRT.

The effect of postmastectomy radiotherapy in node-positive triple-negative breast cancer

Background

The value of postmastectomy radiotherapy (PMRT) for pathological node-positive triple-negative breast cancers (TNBC) remains debatable. The aim of this population-based retrospective study was to evaluate the effect of PMRT on survival outcomes in this population.

Methods

Patients diagnosed with stage T1-4N1-N3M0 TNBC between 2010 and 2014 were identified from the Surveillance, Epidemiology, and End Results (SEER) database. We used univariate and multivariate Cox regression hazards method to determine the independent prognostic factors associated with 3-year breast cancer-specific survival (BCSS). The effect of PMRT on 3-year BCSS was analyzed after stratification by pathological staging of groups.

Results

Of the 4398 patients included in this study, 2649 (60.2%) received PMRT. Younger age, black ethnicity, and advanced tumor (T) and nodal (N) stage were the independent predictors associated with PMRT receipt (all P < 0.05). Patients who received PMRT showed better 3-year BCSS (OR = 0.720, 95% CI = 0.642–0.808, P < 0.001) than those that did not. The effect of PMRT on 3-year BCSS was analyzed after stratification by pathological staging of groups. The results showed that PMRT was associated with better 3-year BCSS in patients with stage T3–4N1 (P = 0.042), T1-4N2 (P < 0.001), and T1-4N3 (P < 0.001), while comparable 3-year BCSS was found between the PMRT and non-PMRT cohorts with T1–2N1 disease (P = 0.191).

Conclusions

Radiotherapy achieved better 3-year BCSS in TNBC patients with stage T3–4N1 and T1-4N2–3 disease. However, no survival benefit was found with the addition of PMRT in patients with T1–2N1 TNBC.