Pelvic lymph node status assessed by 18F-fluorodeoxyglucose positron emission tomography predicts low-risk group for distant recurrence in locally advanced cervical cancer: a prospective study.

PURPOSE: To develop a prediction model to identify a low-risk group for distant recurrence in patients with locally advanced cervical cancer treated by concurrent chemoradiation. METHODS AND MATERIALS: Prospectively, 62 patients with locally advanced cervical cancer were recruited as a training cohort. Clinical variables and parameters obtained from positron emission tomography (PET) and magnetic resonance imaging were analyzed by logistic regression. For the test set, 54 patients were recruited independently. To identify the low-risk group, negative likelihood ratio (LR) less than 0.2 was set to be a cutoff. RESULTS: Among the training cohort, multivariate logistic analysis revealed that advanced International Federation of Gynecology and Obstetrics (FIGO) stage and a high serum squamous cancer cell (SCC) antigen level were significant risk factors (p=0.015 and 0.025, respectively). Using the two parameters, criteria to determine a low-risk subset for distant recurrence were postulated: (1) FIGO Stage IIB or less and (2) pretreatment SCC<2.4 (Model A). Positive pelvic node on PET completely predicted all cases with distant recurrence and thus was considered as another prediction model (Model B). In the test cohort, although Model A did not showed diagnostic performance, Model B completely predicted all cases with distant recurrence and showed a sensitivity of 100% with negative LR of 0. Across the training and test cohort (n=116), the false negative rate was 0 (95% confidence interval 0%-7.6%). CONCLUSIONS: Positive pelvic node on PET is a useful marker in prediction of distant recurrence in patients with locally advanced cervical cancer who are treated with concurrent chemoradiation.

Diagnostic value of (18)F-FDG PET for evaluation of paraaortic nodal metastasis in patients with cervical carcinoma: a metaanalysis.

UNLABELLED: We assessed the diagnostic performance of (18)F-FDG PET in detecting paraaortic lymph node (PALN) metastasis in patients with cervical cancer. METHODS: Through a search of MEDLINE and EMBASE (1980 to March 2009), we performed a random-effects meta analysis. A summary receiver-operating-characteristic curve was constructed using hierarchical regression models. To identify other sources of heterogeneity, regression meta analysis was performed. RESULTS: Patients (n = 385) from 10 studies were analyzed. Although specificity of (18)F-FDG PET was consistent (97%; 95% confidence interval [CI], 93%-99%), sensitivity was low and heterogeneous among the studies (34%; 95% CI, 10%-72%). Although regression meta analysis did not identify any source to which heterogeneity could be attributed, it revealed a trend of increasing sensitivity according to an increase in the prevalence of PALN metastasis (P = 0.001). In the 5 studies with prevalence greater than 15%, estimated sensitivity and specificity were 73% (95% CI, 53%-87%) and 93% (95% CI, 86%-97%), respectively. With the diagnostic performance, assuming the prevalence of 15%, the calculated false-positive and -negative rates were 35% and 5%, respectively. CONCLUSION: In detecting PALN metastasis, PET performs acceptably only in populations with a relatively high probability of PALN metastasis. Otherwise, we found no evidence to justify the evaluation of PALN based solely on PET in cervical cancer.