Weill Cornell researchers at Memorial Sloan Kettering Cancer Center are recommending the use of PET/CT with the radiotracer fludeoxyglucose (18F-FDG PET/CT) for many patients with newly diagnosed breast cancer.
Gary Ulaner, MD, PhD, and colleagues base their recommendation on their study of 238 patients with estrogen receptor-positive/human epidermal growth factor receptor-negative (ER+/HER2-) cancers and 245 patients with human epidermal growth factor receptor-positive HER2+ cancers.
The initial stage was determined from mammography, ultrasound, MRI and/or surgery.
The team’s findings, published online April 29 in the European Journal of Nuclear Medicine and Molecular Imaging, show that, for cohort patients with ER+/HER2-breast cancer, 18F-FDG PET/CT revealed unsuspected distant metastases in three of 71 (4 percent) initial stage IIA, 13 of 95 (14 percent) stage IIB and 15 of 57 (26 percent) stage III cancers.
For patients with HER2+ breast cancer, the modality ferreted out unsuspected distant metastases in three of 72 (4 percent) initial stage IIA, 13 of 93 (14 percent) stage IIB and 13 of 59 (22 percent) stage III cancers.
The overall upstaging rate for IIB cancer was 14 percent (95 percent confidence interval).
The authors note this rate’s similarity to upstaging rates previously seen in patients with stage IIB triple-negative breast cancer.
“The detection of unsuspected distant metastases in these patients alters treatment and prognosis,” Ulaner et al. write. “National Comprehensive Cancer Network guidelines should consider adding patients with stage IIB breast cancer for consideration of systemic staging with 18F-FDG-PET/CT at the time of initial diagnosis.”