Prognostic analysis in a Chinese population with T1-2N1 breast cancer: Did patients with 1 or 2, and 3 positive axillary lymph nodes have similar survival outcomes?

The prognostic differences and the effect of postmastectomy radiotherapy between post-chemotherapy ypT1-2ypN1 and de novo pT1-2N1 breast cancer

BACKGROUND

The prognosis and the value of postmastectomy radiotherapy (PMRT) between post-chemotherapy ypT1-2ypN1 and de novo pT1-2N1 breast cancer (BC) remain controversial. We aimed to evaluate the prognostic differences and the effect of PMRT between the two patient subsets.

METHODS

Patients diagnosed with pT1-2N1M0 BC were identified between 2010 and 2018. The study endpoints were overall survival (OS), breast cancer-specific survival (BCSS), locoregional recurrence-free survival (LRFS), distant metastasis-free survival (DMFS) and disease-free survival (DFS). The chi-square test, Kaplan-Meier method and Cox regression analysis were used for data analysis.

RESULTS

Total number of 2103 pT1-2N1M0 BC patients were included in the study, including 270 post-chemotherapy (97 without PMRT, 173 with PMRT) and 1833 de novo cases (993 without PMRT, 840 with PMRT). No significant differences were found between post-chemotherapy ypT1-2ypN1 and de novo pT1-2N1 BC patients in 5-year OS (p = 0.068), BCSS (p = 0.054), LRFS (p = 0.241), DMFS (p = 0.104) or DFS (p = 0.08). PMRT did not improve any survival outcome in patients receiving neoadjuvant chemotherapy; however, the PMRT group had a better 5-year BCSS (97.0% vs. 95.8%, p = 0.033) in de novo pT1-2N1 BC. Cox multivariate analysis demonstrated that PMRT was a significant independent predictor of BCSS (HR 0.628; 95% CI, 0.403-0.978; p = 0.04) in de novo pT1-2N1 patients.

CONCLUSIONS

There seemed no survival difference in post-chemotherapy ypT1-2ypN1 and de novo pT1-2N1 BC patients with contemporary systemic therapy. In addition, PMRT might be exempted in patients with post-chemotherapy ypT1-2ypN1 BC, while not in patients with de novo pT1-2N1 BC.

Role of postmastectomy radiation therapy in breast cancer patients with T1-2 and 1-3 positive lymph nodes

Objective

To evaluate the role of radiotherapy (RT) in overall survival (OS) and disease-free survival in postmastectomy breast cancer patients with tumor size <5 cm, with 1–3 involved axillary lymph nodes (T1–2N1).

Patients and methods

We conducted a retrospective study of 89 postmastectomy patients with T1–2N1 disease between 2005 and 2015 at the Radiation Oncology Clinic of Kayseri Training and Research Hospital. Clinicopathologic, demographic, and laboratory findings, as well as treatment regimens were investigated. OS and disease-free survival as well as factors that can be valuable in the prognosis were evaluated.

Results

A total of 89 female patients with an average age of 53 years (range: 30–81 years) were included in the assessment. Five-year and 10-year local recurrence rates were found to be 6.6% in the RT group and 7.1% in the non-RT group. In the RT group, the mean OS was 110.3 months and progression-free survival was 104.4 months. In the non-RT group, the corresponding figures were 104.3 months and 92.1 months, respectively. Statistically significant correlation was observed between RT and the American Joint Committee on Cancer stage (P<0.001), histological type (P=0.013), tumor size (P<0.001), and lymph node metastasis (P<0.001). During the assessment, locoregional recurrence and/or distant metastasis occurred in nine patients (10%). Locoregional recurrence was observed mostly in patients with invasive ductal carcinoma, tumor >3.0 cm in size, grade II tumors, and perinodal invasion, and who were premenopausal at the time of diagnosis.

Conclusion

In T1–2N1 breast cancer patients who underwent modified radical mastectomy, when the effects of postmastectomy RT were evaluated, there were no differences in terms of OS and progression-free survival. In addition, when subgroup analysis was made, in patients with invasive ductal carcinoma, tumor diameter >2 cm, three lymph node metastasis, and stage 2b, postmastectomy RT was seen to be useful.