Prognostic significance of volume-based metabolic parameters in uterine cervical cancer determined using 18F-fluorodeoxyglucose positron emission tomography.
ABSTRACT We compared the prognostic value of volume-based metabolic parameters determined using fluorine 18 (F) fluorodeoxyglucose (FDG) positron emission tomography (PET) (F-FDG PET) (with other prognostic parameters in uterine cervical cancer.
The subjects were 73 female patients who had an initial diagnosis of uterine cervical cancer and who underwent F-FDG PET. Various metabolic or volume-based PET parameters including maximum and average standardized uptake values, metabolic tumor volume, and total lesion glycolysis (TLG) were measured in primary cervical tumors. Survival analysis for disease-free survival or progression-free survival was performed with a Kaplan-Meier method using PET parameters and other clinical variables. For determining independent prognostic factors, Cox regression analysis was performed.
Recurrence or disease progression occurred in 23 patients (31.5%). In univariate analysis, patient age (cutoff, 57 years, P < 0.05), International Federation of Gynecology and Obstetrics stage (P = 0.07), primary tumor size (cutoff, 6.7 cm; P < 0.05), lymph node status on PET (P < 0.005), treatment method (P < 0.01), metabolic tumor volume (cutoff, 82 cm; P = 0.001), and TLG (cutoff, 7600; P = 0.005) were significant predictors of recurrence or progression. In multivariate analysis, both lymph node status on PET (hazard ratio, 1.042 [negative vs intrapelvic metastasis only], 7.008 [negative vs extrapelvic metastasis]; P < 0.001) and TLG (cutoff, 7600; hazard ratio, 2.981; P < 0.05) were independent prognostic factors for predicting recurrence.
In uterine cervical cancer, TLG, a volume-based metabolic parameter, and lymph node status on PET may be significant independent prognostic factors for event-free survival.
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ABSTRACT: There is substantial risk that prognosis determined with routine clinical staging for cervical cancer may be inaccurate. This is primarily due to understaging due to the lack of detection of nodal disease. This is particularly true for para-aortic nodal metastases. Treatment based on such staging may also be inadequate for the same reason. Positron emission tomography (PET) has been demonstrated to be useful in the staging of cervical cancer and superior to either computed tomography or magnetic resonance imaging in the detection of nodal disease. Our objective was to determine the prognostic value of pretreatment 2-[(18)F]-fluoro-2-deoxy-d-glucose (FDG) PET scan in women with cervical cancer. We reviewed the records of 56 women with cervical cancer who underwent FDG PET scan prior to treatment. The primary outcome was the effect of abnormal FDG uptake consistent with metastatic nodal disease on 20-month disease-free survival. The pretreatment PET scan demonstrated abnormal FDG uptake in the pelvic nodes alone in 14 (25%) women, in pelvic and para-aortic nodes in 10 (17.9%), and in neither pelvic nor para-aortic nodes in 32 (57.1%). Women with positive pelvic nodes by PET as well as women with positive para-aortic nodes had significantly poorer 20-month disease-free survival compared to women with negative nodes (P= 0.0003 and P= 0.0017, respectively). We conclude that pretreatment FDG PET scan revealing abnormal FDG uptake consistent with nodal disease is a robust predictor of disease recurrence and may alter the therapeutic management of some patients.International Journal of Gynecological Cancer 08/2007; 17(5):1062-7. · 1.94 Impact Factor
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ABSTRACT: To develop guidelines for performing and interpreting positron emission tomography (PET) imaging for treatment assessment in patients with lymphoma both in clinical practice and in clinical trials. An International Harmonization Project (IHP) was convened to discuss standardization of clinical trial parameters in lymphoma. An imaging subcommittee developed consensus recommendations based on published PET literature and the collective expertise of its members in the use of PET in lymphoma. Only recommendations subsequently endorsed by all IHP subcommittees were adopted. PET after completion of therapy should be performed at least 3 weeks, and preferably at 6 to 8 weeks, after chemotherapy or chemoimmunotherapy, and 8 to 12 weeks after radiation or chemoradiotherapy. Visual assessment alone is adequate for interpreting PET findings as positive or negative when assessing response after completion of therapy. Mediastinal blood pool activity is recommended as the reference background activity to define PET positivity for a residual mass > or = 2 cm in greatest transverse diameter, regardless of its location. A smaller residual mass or a normal sized lymph node (ie, < or = 1 x 1 cm in diameter) should be considered positive if its activity is above that of the surrounding background. Specific criteria for defining PET positivity in the liver, spleen, lung, and bone marrow are also proposed. Use of attenuation-corrected PET is strongly encouraged. Use of PET for treatment monitoring during a course of therapy should only be done in a clinical trial or as part of a prospective registry.Journal of Clinical Oncology 03/2007; 25(5):571-8. · 18.04 Impact Factor
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ABSTRACT: To develop standardized correlates of [18F]fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET) standard uptake value (SUV) to computed tomography (CT)-based window and levels. Nineteen patients with non-small-cell lung cancer who underwent imaging with positron emission tomography (PET) and CT were selected. A method of standardizing SUV within CT planning software was developed. A scale factor, determined by a sensitivity calibration of the PET scanner, converts voxel counts to activity per gram in tissue, allowing SUVs to be correlated to CT window and levels. A method of limiting interobserver variations was devised to enhance "edges" of regions of interest based on SUV thresholds. The difference in gross tumor volumes (GTVs) based on CT, PET SUV >or= 2.5, and regions of 40% maximum SUV were analyzed. The mean SUV was 9.3. Mean GTV volumes were 253 cc for CT, 221 cc for SUV >or= 2.5, and 97 cc for SUV40%Max. Average volume difference was -259% between >or=2.5 SUV and CT and -162% between SUV40%Max and CT. Percent difference between GTV >or= 2.5 SUV and SUV40%Max remained constant beyond SUV > 7. For SUVs 4-6, best correlation among SUV thresholds occurred at volumes near 90 cc. Mean percent change from GTVs contoured according to CT (GTV CT) was -260% for GTV2.5 and -162% for GTV40%Max. Using the SUV40%Max threshold resulted in a significant alteration of volume in 98% of patients, while the SUV2.5 threshold resulted in an alteration of volume in 58% of patients. Our method of correlating SUV to W/L thresholds permits accurate displaying of SUV in coregistered PET/CT studies. The optimal SUV thresholds to contour GTV depend on maximum tumor SUV and volume. Best correlation occurs with SUVs >6 and small volumes <100 cc. At SUVs >7, differences between the SUV threshold filters remain constant. Because of variability in volumes obtained by using SUV40%Max, we recommend using SUV >or= 2.5 for radiotherapy planning in non-small-cell lung cancer.International Journal of Radiation OncologyBiologyPhysics 04/2007; 67(3):720-6. · 4.52 Impact Factor