Adjuvant chemotherapy for breast cancer patients with axillary lymph node micrometastases

Evaluation of adjuvant therapy for T1-2N1miM0 breast cancer without further axillary lymph node dissection

Background

For breast cancer (BC) with sentinel lymph node micrometastases (SLNMs), there are limited data to guide the selection of postoperative adjuvant therapy. This study aimed to identify target populations who might benefit most from adjuvant therapy and examine prognostic factors among patients with T1-2N1miM0 BC with one or two SLNMs who underwent sentinel lymph node biopsy (SLNB) alone.

Methods

There were 7,423 patients diagnosed with T1-2N1miM0 BC between 2010 and 2015, and patients with one or two SLNMs were extracted from the Surveillance, Epidemiology, and End Results database. All the patients underwent SLNB alone without further axillary lymph node dissection, and they were stratified according to adjuvant therapy. The statistical significance of categorical variables was analyzed using the χ ² test. Univariable and multivariable Cox analyses were used to analyze characteristics predictive of Breast-cancer-specific survival and overall survival (OS). Kaplan-Meier methods with the log-rank test was analyzed to compare survival difference between the different treatments.

Results

Adjuvant chemotherapy and radiotherapy improved 5-year OS rates. Multivariate analysis revealed that age ≥70 years, high grade, T2 stage, triple-negative subtype, and absence of radiotherapy were poor prognostic factors for OS. Patients who received breast-conserving surgery (BCS), and those with invasive ductal carcinoma (IDC), luminal A, luminal B, or basal-like subtype, and T1c or T2 stage benefited from adjuvant radiotherapy. Patients who received BCS, and those with IDC, luminal A subtype, and T1b, T1c, or T2 stage benefited from adjuvant chemotherapy.

Conclusion

Our findings provide a clinical evaluation of treatment choice after surgery, which may help clinicians make individualized clinical decisions.

Advanced diagnostic imaging of sentinel lymph node in early stage breast cancer

Sentinel lymph node biopsy has been regarded as the standard procedure for early staging breast cancer. One of the key steps is to locate the sentinel lymph node (SLN). The recommended method is the joint use of blue dye and radioisotope. However, due to radionuclide radiation and high cost, it is urgent to develop more convenient and sensitive imaging methods to accurately locate SLN. This article discusses the advancement of accurately locating SLN by isotope tracer imaging, magnetic tracer method, computed tomographic lymphography, and trans-lymphatic contrast-enhanced ultrasound, as well as proposing new propose for clinical diagnosis.

Prognosis and Chemotherapy Use in Breast Cancer Patients with Multiple Lymphatic Micrometastases: An NCDB Analysis

BACKGROUND

The number of involved lymph nodes negatively affects prognosis in breast cancer patients. Nevertheless, current staging and treatment recommendations do not distinguish between patients with single versus multiple lymphatic micrometastases. In this study, we aim to better characterize these patients.

METHODS

The National Cancer Database was retrospectively queried to identify 486,800 women with stage I-III, estrogen receptor-positive/progesterone receptor-positive/human epidermal growth factor receptor 2-negative (ER+/PR+/HER2-) breast cancer and nodal status of N0, N1mi with 1 (Nmic1) or more (Nmic > 1) involved nodes, and N1 with 1 involved node (N1.1), from 2010 to 2016. Patients with different nodal statuses were compared regarding treatment characteristics, survival, and benefit from chemotherapy by their 21-gene recurrence score (RS).

RESULTS

Of the 23,072 N1mi patients, 88.3% were Nmic1 and 11.7% were Nmic > 1. Nmic > 1 patients were younger, had larger and higher-grade tumors, with more lymphovascular invasion, and were more commonly treated by axillary dissection, radiation, and chemotherapy than Nmic1 patients. In that, they were comparable with N1.1 patients. Five-year survival of Nmic > 1 patients (88.1%) was worse than Nmic1 patients (90.1%; p = 0.02), but similar to N1.1 patients (87.9%). Nmic1, Nmic > 1, and N1.1 patients with RS 11-25 exhibited a < 2% absolute survival benefit associated with chemotherapy. With RS > 25, Nmic > 1 patients showed a 3.5% benefit, similar to Nmic1 (4.8%) and lower than N1.1 (10.9%) patients.

CONCLUSIONS

Nmic > 1 breast cancer patients have worse prognoses than Nmic1 patients, similar to N1.1 patients. Our data suggest those patients with RS 11-25 have minimal benefit from chemotherapy. These findings should be taken into account when discussing prognosis and considering chemotherapy in patients with lymphatic micrometastases.