Irene Andrea Burger, Presenter: Nothing to Disclose

Debra Goldman BS, Abstract Co-Author: Nothing to Disclose

Heiko Schoder MD, Abstract Co-Author: Nothing to Disclose

Hedvig Hricak MD, PhD, Abstract Co-Author: Nothing to Disclose

It has been reported that FDG uptake in the testicles correlates with fertility and age. Also, it is known that chemotherapy agents lead to a substantial reversible or irreversible reduction in fertility; therefore, it is possible that change in testicular FDG activity in patients undergoing chemotherapy could serve as a surrogate marker to monitor fertility. The purpose of this study was to analyze the effect of chemotherapy on FDG uptake in the testes.

Fifty patients (mean age 45±19, range 13-81 years) monitored with FDG PET-CT to assess treatment response for lymphoma were selected for this retrospective analysis under an institutional review board waiver. Overall, 30 scans obtained before treatment, 97 obtained during chemotherapy and 160 obtained after therapy were assessed for FDG activity in the testes as well as blood pool activity. Clustered Wilcoxon rank tests were used to analyze the correlation between FDG activity and chemotherapy status, as well as blood pool activity.

Testicular FDG uptake was statistically significantly lower before treatment (mean SUV: 2.96±0.15) than during (mean SUV: 3.3±0.14, p=0.03) or after chemotherapy (mean SUV: 3.43±0.10, p=0.01). Testicular FDG uptake did not decrease in patients under chemotherapy. During follow-up after chemotherapy (mean 3.7 ± 4 years, range 33 days–15 years) testicular FDG uptake did not significantly increase over time. There was a statistically significant correlation between blood pool activity and FDG uptake in the testes (p<0.001).

In this study, FDG activity in the testes did not decrease under chemotherapy, which suggests that testicular FDG activity may not correlate with fertility. The high correlation between testicular FDG uptake and blood pool activity may reflect the fact that the testes are well-perfused organs.

FDG activity in the testes is more likely to be related to blood pool activity than to fertility. FDG PET/CT therefore cannot be used to monitor fertility during chemotherapy.

Burger, I, Goldman, D, Schoder, H, Hricak, H, Analysis of the Impact of Chemotherapy on Physiologic Testicular FDG Activity.  Radiological Society of North America 2012 Scientific Assembly and Annual Meeting, November 25 - November 30, 2012 ,Chicago IL. http://archive.rsna.org/2012/12033770.html