Abstract P5-08-25: Body mass index and liver metastasis in women with invasive breast carcinoma
Authors: Barron Cynthia Reyes , Planas-Silva Maricarmen , Hicks David G , Turner Bradley M 
Published: March 2020

INTRODUCTION: Breast cancer is the most prevalent non-skin cancer in women worldwide. Women with metastatic breast cancer to the liver have poor outcomes compared to metastases to other sites, frequently develop resistance to available hormonal and chemotherapeutic agents, and have poor overall survival. Conflicting evidence exists regarding the association of body mass index (BMI) with progression free and overall survival in patients with metastatic breast cancer.

METHODS: A single institution retrospective study of women with breast cancer metastasis to the liver was conducted. The pathology reports and medical records from 2011 to 2017 were searched to identify cases with biopsy proven liver metastases. Several factors were considered including breast cancer histologic type and stage at diagnosis; estrogen receptor, progesterone receptor, and HER2-neu amplification status of the initially diagnosed breast cancer as well as the metastatic disease; patient age and ethnicity; BMI (kg/m2) at time of metastasis and at initial diagnosis; and, outcome to include survival after liver metastasis diagnosis.

RESULTS: In our population, the BMI ranged from 21.2 kg/m2 to 56.3 kg/m2 (mean 28.4 kg/m2). Eighteen patients (62%) were either overweight or obese. Twenty-one patients (72.4%) were deceased at the time of the study with an average survival of 659 days after liver metastasis diagnosis (Table 1). Patients with a BMI &gt; 30 (obese) had a significantly lower (p &lt;0.0005) mean survival than patients who were overweight (BMI 25.0 kg/m2 - 29.9 kg/m2). Patients who were overweight had a significantly lower mean survival than patients who had a normal BMI (18.5 kg/m2 -24.9 kg/m2). Five patients with liver metastases survived greater than 2000 days. The mean BMI of these five patients was 25.4 kg/m2. CONCLUSION: Obesity is a well-known cause of co-morbidities, and has been suggested to negatively impact the prognosis in breast cancer. In patients with liver metastases, our data suggests that an increased BMI is associated with decreased survival. This appears to be consistent in both ER positive and Her-2 positive patients (Table 1). This finding may be true regardless of the metastatic site. Further investigation on BMI and patients with metastatic disease to the liver and other organs are needed. We continue to collect data on patients with metastatic disease to the liver and other sites, including bone, to further validate our findings.

Table 1: Mean overall survival in patients with liver metastasisTotalER+ Liver MetastasisHER2+ Liver MetastasisBMI kg/m2N (%)Mean Survival (days)*N (%)Mean Survival (days)*N (%)Mean Survival (days)*Underweight (&lt;18.5)0NA0NA0NANormal (18.5-24.9)6 (28.6)923.85 (31.3)1085.42 (40)547.5Overweight (25.0-29.9)8 (38.1)753.54 (25)7080NAObese (&gt; 30)7 (33.3)3237 (43.7)3233 (60)315NA: not applicable*p-values &lt;0.0005

Citation Format: Cynthia Reyes Barron, Maricarmen Planas-Silva, David G Hicks, Bradley M Turner. Body mass index and liver metastasis in women with invasive breast carcinoma [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P5-08-25.