18F-Fluorodeoxyglucose positron emission tomography optimizes neoadjuvant chemotherapy for primary breast cancer to achieve pathological complete response

Background

To assess the usefulness of positron emission tomography combined with computed tomography using ¹⁸F-fluorodeoxyglucose (FDG PET/CT) for optimizing chemotherapy during neoadjuvant chemotherapy for primary breast cancer.

Methods

One hundred and eight patients (110 tumors) with breast cancer (??2?cm, stages II and III) received neoadjuvant chemotherapy consisting of an anthracycline-based regimen and taxane. The maximal value of the baseline standardized uptake value (SUV) and the change in SUV after four cycles of an anthracycline-based regimen relative to baseline SUV were assessed for predicting pathological complete response (pCR) after sequential taxane.

Results

Tumors with pCR had significantly higher baseline SUV (9.3?±?3.7 SD) compared to those with non-pCR (7.2?±?3.8 SD) (p?=?0.02), but there was a considerable overlap between two groups. On PET scan after four cycles of chemotherapy, thirty-three patients (33.7%) with a 72.1% or greater reduction in SUV were considered as responders and the performance in predicting pCR had a sensitivity of 88.9% and specificity of 78.7%.

Conclusion

The baseline SUV could not be a useful indicator for predicting pCR due to the wide range in sensitivity. On the other hand, a relative change in SUV after completion of an anthracycline-based regimen could be useful for predicting pCR.