Abstract 2825
Background
Dedicated breast positron emission tomography (DbPET) can detect intratumoral heterogeneity using 18F-fluorodeoxyglucose (FDG). We have proved that intratumoral heterogeneous distribution of FDG on DbPET was significantly related with high nuclear grade and high Ki-67 proliferation index (Breast Cancer Res Treat 2018; 171:315–23). We aimed to evaluate whether intratumoral heterogeneous distribution of FDG on DbPET can predict the effects of neoadjuvant chemotherapy (NAC) on breast cancer.
Methods
We evaluated 58 consecutive patients with breast cancer who underwent DbPET before NAC concurrently between August 2016 and March 2018. The relationships between the pathological response for NAC and the maximum standard uptake values (SUVmax) of DbPET, including estrogen receptor (ER) and human epidermal growth factor receptor type-2 (HER2) statuses, and the intratumoral heterogeneous distribution of FDG on DbPET, were evaluated.
Results
Breast cancer with intratumoral heterogeneous distribution of FDG on DbPET showed a tendency to be related with pathological complete response (pCR) (Table). The SUVmax of DbPET showed an increasing tendency with intratumoral heterogeneous distribution. ER positive-breast cancer with intratumoral heterogeneous distribution showed a tendency to be related with pCR.Table: 278P
Relation between biological factors and pathological response
| pCR | Non-pCR | p | |
|---|---|---|---|
| Grade | 0.17 | ||
| 1–2 | 3 | 10 | |
| 3 | 20 | 25 | |
| Ki-67 | 0.35 | ||
| < 20% | 1 | 4 | |
| ≥ 20% | 22 | 31 | |
| ER | 0.07 | ||
| positive | 15 | 24 | |
| negative | 8 | 11 | |
| HER2 | 0.06 | ||
| positive | 13 | 11 | |
| negative | 10 | 24 | |
| DbPET, intratumoral distribution | 0.23 | ||
| Heterogeneity | 19 | 24 | |
| Homogeneity | 4 | 11 |
Conclusions
The SUVmax of DbPET associates with intratumoral heterogeneous distribution. In addition, intratumoral heterogeneity on DbPET provides predictive value for achieving pCR on ER positive-breast cancer and might inform therapeutic decisions.
Clinical trial identification
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Editorial Acknowledgement
Disclosure
All authors have declared no conflicts of interest.