Physiologic 18F-FDG uptake in the fallopian tubes at mid cycle on PET/CT.

Abstract

We observed bilateral pelvic foci of (18)F-FDG uptake (BiPF) exclusively in females--a finding not previously reported--and assessed the frequency, anatomic localization, and clinical significance of the uptake. On (18)F-FDG PET/CT and coregistered contrast-enhanced CT scans of 159 females (age, 16-81 y), the presence of BiPF and their location were evaluated. The findings were correlated with the age and menstrual history of the patient. BiPF were seen in 14 (22%) of 63 patients up to 53 y old, predominantly at mid menstrual cycle, and were best coregistered to the fallopian tubes on contrast-enhanced CT. None of 96 patients older than 53 y showed BiPF. Fallopian (18)F-FDG uptake was seen predominantly in premenopausal women at mid menstrual cycle. This finding is in accordance with known cyclic changes of fallopian tubes in response to ovarian hormones and may be the first, to our knowledge, imaging evidence revealing the influence of estrogen on the fallopian tubes.