[Prognostic value of pretherapeutic 18F-FDG PET/CT in cancer of the uterine cervix: a retrospective study of 53 patients]

Normal Variants and Pitfalls Encountered in PET Assessment of Gynecologic Malignancies

Combined PET/computed tomography is used for oncological indications. PET/computed tomography benefits from the metabolic information of PET and the anatomic localization of computed tomography. The integrated scanner provides data with accurate registration of anatomy and molecular information. Many physiologic conditions, normal variants, and benign lesions within the pelvis and the body can cause confusion and uncertainty. False-negative results owing to low ¹⁸F-fluorodeoxyglucose uptake from the tumor can produce diagnostic challenges and inaccurate conclusions. This article reviews normal variants and potential pitfalls encountered in PET assessment of gynecologic malignancies to provide useful information for the referring and reporting physicians.

Additional Prognostic Value of SUVmax Measured by F-18 FDG PET/CT over Biological Marker Expressions in Surgically Resected Cervical Cancer Patients

PURPOSE

We compared the prognostic ability of the maximum standardized uptake value (SUVmax) and various biological marker expressions to predict recurrence in patients with surgically resected cervical cancer.

METHODS

A retrospective review identified 60 patients with cervical cancer who received [18F]fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT) at the time of the diagnosis of cancer. The SUVmax, expressions of carbonic anhydrase-IX (CA-IX), glucose transporter 1 (GLUT-1), and vascular endothelial growth factor (VEGF), and known prognostic factors were investigated.

RESULTS

The median follow-up time was 22.2 months (range 3.4-43.1 months). Using univariate analyses, the stage (stage II, p = 0.0066), SUVmax (> 6, p = 0.027), parametrial involvement (p < 0.0001), and positivity for CA-IX (p = 0.0191) were associated with recurrences of cervical cancer. With the Cox proportional hazard regression model, the SUVmax was a potent predictor for disease-free survival (DFS).

CONCLUSION

Although CA-IX expression was related to DFS in the current study, the potent predictor for DFS was SUVmax. Therefore, SUVmax is of greater prognostic value than biological marker expression in patients with surgically resected cervical cancer.