Dual time point 18F-FDG PET imaging detects breast cancer with high sensitivity and correlates well with histologic subtypes.

TLDR

Dual time point (18)F‑FDG PET improves detection of primary breast cancer, achieving sensitivities of 90.1 % for tumors >10 mm, 82.7 % for 4–10 mm, and 76.9 % for noninvasive cancers. This prospective study evaluated the utility of dual time point (18)F‑FDG PET for detecting primary breast cancer and examined whether uptake dynamics correlate with histopathologic subtypes. The authors measured SUVmax at two time points, calculated percent change (Δ%SUVmax), and compared tumor‑to‑background ratios across invasive versus noninvasive tumors and size subgroups. Dual time point imaging showed significant differences in SUVmax and Δ%SUVmax among groups, with higher sensitivity in larger invasive tumors and uptake changes varying by histopathologic subtype.

Abstract

This prospective study was designed to assess the utility of the dual time point imaging technique by (18)F-FDG PET in detecting primary breast cancer and to determine whether there is a relationship between (18)F-FDG uptake and its change over time and the histopathologic subtypes.One hundred fifty-two patients with newly diagnosed breast cancer underwent 2 sequential PET scans (dual time point imaging) for preoperative staging. The maximum standardized uptake value (SUVmax) of (18)F-FDG was measured from both time points. The percent change in SUVmax (Delta%SUVmax) between time points 1 (SUVmax1) and 2 (SUVmax2) was calculated. Patients were divided into 2 groups according to histopathology as invasive and noninvasive. Invasive tumors were also divided into 2 groups (>10 mm and 4-10 mm). The tumor-to-contralateral normal breast (background) ratios of SUVmax at both time points for groups were measured and the Delta%SUVmax values were calculated.The mean +/- SD of the SUVmax1, the SUVmax2, and the Delta%SUVmax were 3.9 +/- 3.7, 4.3 +/- 4.0, and 8.3% +/- 11.5% for invasive; 2.0 +/- 0.6, 2.1 +/- 0.6, and 3.4% +/- 13.0% for noninvasive; and were 1.2 +/- 0.3, 1.1 +/- 0.2, and -10.0% +/- 10.8% for the contralateral normal breast groups, respectively. In the comparison of SUVmax1, Delta%SUVmax, and the tumor-to-background ratios among groups, all results were significant (P < 0.001). Visual assessment revealed that the sensitivity of dual time point imaging was 90.1% for invasive cancer >10 mm, 82.7% for invasive breast cancers 4-10 mm, and 76.9% for noninvasive breast cancers.Dual time point imaging is a simple and noninvasive method that may improve the sensitivity and accuracy of (18)F-FDG PET in assessing patients with primary breast cancer. The changes that are noted in SUVs in dual time point imaging vary depending on the histopathologic type of primary breast cancer.