Staging of primary cervical cancers: the role of nuclear medicine.

In nuclear medicine, [18F]-fluorodeoxyglucose positron emission tomography (18FDG PET) and lymphatic mapping and sentinel lymphadenectomy (LM/SL) may significantly improve the staging of primary cervical cancers. Indeed, the disease progresses in a 'level by level' fashion to regional nodes through the lymphatic channels, and also to extra-nodal sites via the hematogenous stream. Additionally, the sub-optimal efficacy of routine radiological protocols, while new combined therapies are proving to be more efficient, stresses the need for alternative staging procedures. Current data suggest that LM/SL accurately reflects the regional lymph node status in early stage cervical cancers, and thus could avoid unnecessary complete lymphadenectomies. Also, whole body 18FDG PET may provide valuable insights on extra-pelvic and distant tumor spreading, with a significant impact on treatment choices. If these promising results are confirmed on large controlled trials, LM/SL and 18FDG PET imaging could be incorporated in the routine staging work-up of primary cervical cancers.

Contribution of whole-body 18FDG PET imaging in the management of cervical cancer.

OBJECTIVE: The objective of this study was to assess the contribution of [(18)F]fluoro-2-deoxy-D-glucose positron emission tomography ((18)FDG PET) imaging in the management of cervical cancer. METHODS: Fully corrected whole-body PET was performed in 60 patients (pts) with proven cervical cancer. In pretreatment staging, 22 pts underwent PET in addition to routine protocol including International Federation of Obstetrics and Gynecology (FIGO) staging and pelvic magnetic resonance imaging (MRI). Eighteen of them had pelvic lymphadenectomy. After treatment, PET was performed in 38 pts routinely followed up by clinical and radiological examinations. Results of PET and routine protocols were compared to final diagnoses, including histological findings in 31 pts and clinical outcomes in the other cases. Median follow-up time was 12 +/- 7.3 months. RESULTS: In all but 2 patients (FIGO stage IA), both PET and MRI detected the primary tumor. In 6 pts, MRI alone noted loco-regional tumor spread but PET localized 9 unsuspected extrapelvic nodal sites (6 para-aortic, 2 mediastinal, and 1 supra-clavicular). However, PET missed 8 microscopic pelvic nodal metastases. In 18% of the patients, PET staging significantly influenced the treatment choices. In follow-up, PET accurately diagnosed a recurrent disease in 13 pts with falsely negative or equivocal conventional imaging (CI). Ten patients with a negative PET were still in complete remission after a minimal follow-up time of 12 months. Overall, the agreement of PET with final diagnosis was significantly better than that of routine protocol (P < 0.05). CONCLUSIONS: Whole-body (18)FDG PET appears useful in the management of cervical cancer, in particular for staging extrapelvic metastases or optimally detecting a recurrence. MRI is better indicated for evaluating the loco-regional status of the disease.