Positron emission tomography for evaluating para-aortic nodal metastasis in locally advanced cervical cancer before surgical staging: A surgicopathologic study

Purpose: positron emission tomographic (PET) scanning provides a novel mean s of imaging malignancies, This prospective study was undertaken to evaluat e PET scanning in detecting para-aortic nodal metastasis in patients with l ocally advanced cervical carcinoma and no evidence of extrapelvic disease b efore planned surgical staging lymphadenectomy. Materials and Methods: After 20 mCi of 2-[F-18]fluoro-2-deoxy-D-glucose (FD G) were administered intravenously, the abdomen and pelvis were scanned. Co ntinuous bladder irrigation was used to reduce artifact. Patients were clas sified by the presence or absence of FDG uptake in the primary tumor and in pelvic or para-aortic nodes. Para-aortic node metastases were classified a s present or absent according to a standardised staging procedure. Pelvic n ode metastases were similarly classified in a subset of patients who underw ent pelvic node resection, Results: Thirty-two patients with stage IIB (n = 6), IIIB (n = 24), and IVA (n = 2) tumors were studied. Fluorodeoxyglucose was taken up by 91% of the cervical tumors. Six of eight patients with positive para-aortic node meta stasis held PET scan evidence of para-aortic nodal metastasis. One of the t wo false-negatives had only one microscopic focus of metastatic cancer. In the para-aortic nodes, PET scanning had a sensitivity of 75%, a specificity of 92%, a positive predictive value of 75%, and a negative predictive valu e of 92%. Fluorodeoxyglucose para-aortic nodal uptake conferred a relative risk of 9.0 (95% confidence interval, 2.3 to 36.0) for para-aortic nodal me tastasis. All 10 of 17 patients with metastasis were predicted by PET scann ing (P < .001); five of these patients had abnormalities on computed tomogr aphic scans. Conclusion: Cervical cancers have a high avidity for FDG. The use of PET-FD G scanning accurately predicts both the presence and absence of pelvic and para-aortic nodal metastatic disease. J Clin Oncol 17:41-45. (C) 1999 by American Society of Clinical Oncology.