RT Journal Article
SR Electronic
T1 Use of <sup>64</sup>Cu-DOTA-Trastuzumab PET to Predict Response and Outcome of Patients Receiving Trastuzumab Emtansine for Metastatic Breast Cancer: A Pilot Study
JF Journal of Nuclear Medicine
JO J Nucl Med
FD Society of Nuclear Medicine
SP 1145
OP 1148
DO 10.2967/jnumed.121.262940
VO 63
IS 8
A1 Mortimer, Joanne E.
A1 Bading, James R.
A1 Frankel, Paul H.
A1 Carroll, Mary I.
A1 Yuan, Yuan
A1 Park, Jinha M.
A1 Tumyan, Lusine
A1 Gidwaney, Nikita
A1 Poku, Erasmus K.
A1 Shively, John E.
A1 Colcher, David M.
YR 2022
UL http://jnm.snmjournals.org/content/63/8/1145.abstract
AB We hypothesized that functional imaging with 64Cu-DOTA-trastuzumab PET/CT would predict the response to the antibody–drug conjugate trastuzumab–emtansine (T-DM1). Methods: Ten women with metastatic human epidermal growth factor receptor 2–positive breast cancer underwent 18F-FDG PET/CT and 64Cu-DOTA-trastuzumab PET/CT on days 1 and 2 before treatment with T-DM1. Results: T-DM1–responsive patients had higher uptake than nonresponsive patients. Day 1 minimum SUVmax (5.6 vs. 2.8, P &lt; 0.02), day 2 minimum SUVmax (8.1 vs. 3.2, P &lt; 0.01), and day 2 average SUVmax (8.5 vs. 5.4, P &lt; 0.05) for 64Cu-DOTA-trastuzumab all favored responding patients. Tumor-level response suggested threshold dependence on SUVmax. Patients with a day 2 minimum SUVmax above versus below the threshold had a median time to treatment failure of 28 mo versus 2 mo (P &lt; 0.02). Conclusion: Measurement of trastuzumab uptake in tumors via PET/CT is promising for identifying patients with metastatic breast cancer who will benefit from T-DM1.