Role of [18F]fluoro-2-deoxy-D-glucose positron emission tomography in re-recurrent cervical cancer

Cervical cancer - staging and restaging with 18F-FDG PET/CT

The Guidelines Project, an initiative of the Brazilian Medical Association, aims to combine information from the medical field in order to standardize producers to assist the reasoning and decision-making of doctors. The information provided through this project must be assessed and criticized by the physician responsible for the conduct that will be adopted, depending on the conditions and the clinical status of each patient.

Recent Trends in PET Image Interpretations Using Volumetric and Texture-based Quantification Methods in Nuclear Oncology

Image quantification studies in positron emission tomography/computed tomography (PET/CT) are of immense importance in the diagnosis and follow-up of variety of cancers. In this review we have described the current image quantification methodologies employed in (18)F-fluorodeoxyglucose ((18)F-FDG) PET in major oncological conditions with particular emphasis on tumor heterogeneity studies. We have described various quantitative parameters being used in PET image analysis. The main contemporary methodology is to measure tumor metabolic activity; however, analysis of other image-related parameters is also increasing. Primarily, we have identified the existing role of tumor heterogeneity studies in major cancers using (18)F-FDG PET. We have also described some newer radiopharmaceuticals other than (18)F-FDG being studied/used in the management of these cancers. Tumor heterogeneity studies are being performed in almost all major oncological conditions using (18)F-FDG PET. The role of these studies is very promising in the management of these conditions.

Outcomes and prognosis of patients with recurrent cervical cancer after radical hysterectomy

OBJECTIVE

Our aim was to investigate the clinical features and outcomes following recurrence after primary radical hysterectomy for cervical cancer.

METHODS

Clinical data of 121 documented recurrent cervical cancer patients who received primary radical hysterectomy and bilateral pelvic lymphadenectomy between 1993 and 2000 at Chang Gung Memorial Hospital were retrospectively reviewed. Clinicopathological variables, primary treatment, failure pattern, salvage treatment and outcomes were analyzed. Outcomes of the current study were compared to those treated between 1982 and 1992 (1982-1992 cohort).

RESULTS

Cancer recurrence was documented at a median time to recurrence (TTR) of 28.4 months (1.2-129.9 months). Assessable failure patterns (n=106) included loco-regional in 46.3%, distant in 47.2% and combined pelvic-distant in 6.6%. 5-year survival of the 121 patients was 22.3% after cancer recurrence. The median survival after recurrence (SAR) was 16.4 months (range 0-144.2 months). By multivariate analysis, extravaginal sites of recurrence (HR 2.56, 1.28-5.12; p=0.008) and HPV16-positive (HR 0.60, 0.38-0.96; p=0.033) were significant prognostic factors for SAR. Non-squamous histology or pelvic node metastasis at primary surgery were not significant (5-year SAR of 16.4% and 20.0%, respectively), though they were (0% and 0%) in the 1993-2000 cohort. Salvage surgery and concurrent chemoradiation were more frequently used in the 1993-2000 cohort (48.3% versus 12.4%).

CONCLUSION

HPV16-negativity and extravaginal relapse were significant poor prognostic factors. Future randomized controlled trials for recurrent cervical cancer could be stratified for these two factors if further studies using external validation confirm these results.

Molecular imaging in the management of cervical cancer

Positron emission tomography (PET), magnetic resonance imaging (MRI), and integrated 18-fluorodeoxyglucose ((18)F-FDG) PET/computed tomography are valuable techniques for assessing prognosis, treatment response after the completion of concurrent chemoradiation, suspicious or documented recurrence, unexplained post therapy elevations in tumor markers, and the response to salvage treatment when managing cervical cancer. However, PET plays a limited role in the primary staging of MRI-defined node-negative patients. Currently, (18)F-FDG is still the only tracer approved for routine use, but several novel targeting PET compounds, high-Tesla MRI machines, diffusion-weighted imaging without contrast, and dynamic nuclear polarized-enhanced (13)C-MR spectroscopic imaging may hold promising applications.