While sentinel lymph node biopsy (SLNB) of axillary lymph nodes has become standard practice for the staging and treatment in early breast cancer, SLNB of parasternal lymph nodes has yet to be established as a routine performance due to its lack of clinical relevance. Possibly because its effectiveness has only been studied in axillary lymph node (ALN)-negative patients.
Over the span of four years, a study to evaluate the significance of parasternal lymph node biopsy in ALN-positive patients was conducted at the Shandong Cancer Hospital in China.
A total of 352 breast cancer patients were enrolled and the results are unequivocal: in 183 patients with confirmed presence of parasternal lymph nodes, the visualization rate was 71.9% (123/171) in patients who had undergone initial surgery, and 33.1% (60/181) in patients who had received neoadjuvant systemic therapy (NST). The average time required for SLNB was 7 minutes, and the median number of lymph nodes identified per patient was 2. Out of 347 excised lymph nodes, 87 were positive for metastasis, with 50.6% concentrated in the second, and 34.5% in the third intercostal space and the metastasis rate was 39.8% (initial surgery) and 13.3% (NST) respectively. Consequently, the diagnosis stage of 57 patients (31.1%) had to be raised.
In conclusion, parasternal lymph node biopsy should be performed routinely in ALN-positive breast cancer patients to ensure more accurate staging and appropriate choice of treatment.
The full study “Internal Mammary Sentinel Lymph Node Biopsy in Clinically Axillary Lymph Node-Positive Breast Cancer: Diagnosis and Implications for Patient Management” (Qiu, PF., Zhao, RR., Wang, W. et al. Ann Surg Oncol (2019). https://doi.org/10.1245/s10434-019-07705-0) was published online on 12 August 2019 and is freely accessible here.