Prediction of axillary lymph node metastasis using tumor volume to breast volume ratio: retrospective cohort study

Tumour size appear to be a risk factor of axillary lymph node metastasis in breast cancer. Recent evidence shows that higher the T staging is associated with higher rate of axillary lymph node metastasis. However, no studies shows that in the same T staging or tumour size but different breast size or breast volume the incidence of axillary lymph node metastasis differ or not .

This Study aimed to investigate the association between tumour to breast ratio in breast cancer as a predictive factor of axillary lymph node metastasis.

This study included 200 consecutive patients diagnosed with breast cancer between January 2012 to march 2022. The authors retrospectively reviewed medical data pathologic report and Ultrasonography and mammography of breast. Tumour diameter reported in pathologic report was used to calculate tumour volume using formula for ellipse. Breast volume was calculate using formula referencing from study of Jack W. Rostas et all by formula Breast Volume=1/3׶×Radius²ccview×Heightccview by measuring from mammography of patient. Tumour volume to breast volume ratio was calculated and analyzed.

Of 200 patient included in this study, 84 patient (42%) was in lymph node positive group and 116 patient (58%) was in lymph node-negative group. Median for tumour and breast volume ratio in node positive group was higher [median 0.0093 (interquartile range=0.0047-0.023)] than in node-negative group [median 0.0065 (interquartile range (0.0028-0.0199)]. P=0.0414 receiver operating characteristic curve for tumour to breast ratio showed AUC of 0.7389 (95% CI 0.67993-0.82335) Which seems to be a significance as predictive factors for Axillary lymph node metastasis.

Higher tumour volume to breast volume ratio tends to be a significance predictive factors for axillary lymph node metastasis in breast cancer patients.