4MO - A prediction model for developing lymphedema in breast cancer patients receiving sentinel node biopsy

Background

While there are numerous studies describing the potential risk factors for developing ipsilateral lymphedema in breast cancer patients who receive axillary node dissection, the risk factors for lymphedema for patients receiving sentinel node biopsy only have not been clearly identified. The aim of this study is to identify risk factors for the postoperative lymphedema in breast cancer patients who underwent sentinel lymph node biopsy only.

Methods

Among the patients who underwent surgery for their breast cancer at Seoul National University Hospital from Jan 2017 to Dec 2020, the patients who received sentinel node biopsy only for their axillary staging were included for this retrospective study.

Results

In this study, we investigated factors associated with the development of lymphedema in a cohort of 5,051 patients. The median age of the patients was 52 years. During a median follow-up of 56.5 months, 49 patients (0.9%) developed ipsilateral lymphedema after surgery, with most cases occurring within the first three years. In multivariate analysis, obesity, radiation therapy, chemotherapy, and more than three sentinel nodes remained independent predictors of lymphedema. We developed a predictive model for lymphedema after sentinel node biopsy, incorporating radiation therapy (coefficient 0.756), chemotherapy (2.030), BMI of 30 or higher (1.390), and more than three sentinel nodes (1.813), with an AUC of 0.824. The model demonstrated a sensitivity of 87.8%, specificity of 66.8%, positive predictive value of 2.5%, and negative predictive value of 99.8%. Systemic chemotherapy was the most influential factor in the model, followed by the number of harvested lymph nodes. Based on these risk factors, patients were classified into four groups, with the high-risk group showing a 3.3% risk of lymphedema, while the low- and medium-low-risk groups had less than 1% risk.

Conclusions

Our study found a 1% risk of lymphedema in breast cancer patients undergoing sentinel node biopsy. We developed a predictive model for identifying high-risk patients, facilitating early intervention and enhancing patient care.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.