368P - Impact of PET-CT-determined sarcopenia on survival and pathological complete response in breast cancer patients with neoadjuvant chemotherapy

Background

Neoadjuvant chemotherapy (NACT) is a frequently used treatment method in breast cancer. Achieving pathological complete response (pCR) is one of the surrogate marker for long-term survival. Sarcopenia is considered a poor prognostic factor in breast cancer. The association between pCR and sarcopenia has not been fully elucidated in neoadjuvant setting in breast cancer. It was aimed to evaluate the effect of sarcopenia on pCR and overall survival (OS) in breast cancer patients with NACT.

Methods

Patients with NACT between 2014 and 2021 were included in the study. SMI (skeletal muscle index), VFA (visceral fat tissue area), sarcopenic obesity (VFA/SMI) were determined at the level of the third lumbar vertebra on PET-CT images before and after NACT. Patients were categorized according to pCR. The relationship between pCR and clinicopathological features and PET-CT parameters were evaluated by logistic regression analysis. Kaplan-Meier method was used for survival analysis.

Results

The medical records of 56 patients who received NACT were reviewed and twenty-three patients who met the inclusion criteria were included in the study. They were classified as sarcopenic according to the previously determined cutoff value for sarcopenia (SMI: 38.9 cm2/m2). Sarcopenia was present in 50% of patients. Post-NACT sarcopeni was found in 20% of the patients. The rate of post -NACT sarcopenic obesity was %27.3. pCR was achieved in 28.3% of patients. Sarcopenia was not associated with clinicopathologic features, pCR and OS. There was no association between clinicopathologic factors and pCR. Recurrence, post treatment high VFA, and post treatment sarcopenic obesity were significantly associated with survival. In multivariate analysis post treatment high VFA level was significantly associated with increased mortality (HR: 3.278 CI: 95% (1.143-9.401), p= 0.027).

Conclusions

Dynamic follow-up for sarcopenic obesity and visceral adipose tissue increase may improve the survival in breast cancer with NACT. Further prospective studies will be elucidated the relationship between breast cancer and sarcopenia.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

G. Tahtacı.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.