1. 11/29/2004RSNA 20041 ACCURACY OF AXILLARY FDG-PET FOR STAGING PRIMARY BREAST CANCER: A META-ANALYSIS BEN A. DWAMENA; GAVIN MACKIE; DIANE THANAGAMI; MARK HELVIE University of Michigan (Departments of Radiology and Nuclear Engineering) & VA Ann Arbor Health Care System (Nuclear Medicine Service)

2. 11/29/2004RSNA 20042 BACKGROUND Axillary node staging is important for treatment and prognostication in operable breast cancer Conventional imaging tests such as CT, MR, scintimammography and xray mammography have suboptimal performance

3. 11/29/2004RSNA 20043 BACKGROUND Thus, axillary dissection and sentinel node biopsy are standard of care These are invasive/minimally invasive and not without clinically significant complications (in up to 20% of patients) The latter has a steep learning curve and variable false-negatives (0-15%)

4. 11/29/2004RSNA 20044 BACKGROUND Several investigators have studied FDG PET as a non-invasive imaging alternative with highly variable results and ongoing lively debate regarding diagnostic operating characteristics We sought to empirically inform this debate by means of a systematic review and meta-analysis of the published diagnostic accuracy studies (vis a vis SLNMB performance)

5. 11/29/2004RSNA 20045 RESEARCH QUESTIONS How accurate is FDG-PET in detecting and/or excluding Axillary Lymph Node Metastases (Sensitivity & Specificity)? How informative is a positive/negative axillary FDG-PET scan (Likelihood Ratios)?

6. 11/29/2004RSNA 20046 METHODS Exhaustive search of multiple databases Selection of relevant studies with 2X2 data Random effects and SROC meta-analyses to obtain performance indices Testing for heterogeneity and selection bias

7. 11/29/2004RSNA 20047 SYSTEMATIC REVIEW 26 datasets(25 studies) of 1743 patient units published 1992-2004 eligible for review Study size: 10-308 Pretest probability of nodal metastases: 48% ( 16%-81%) Reported sensitivity: 56%-100% Reported specificity: 63%-98%

8. 11/29/2004RSNA 20048 ACCURACY

9. 11/29/2004RSNA 20049 INFORMATIVENESS

10. 11/29/2004RSNA 200410 SUMMARY ROC CURVE Threshold SEN: 0.98 (0.94-1.00) Threshold SPE: 0.75 (0.74-0.76)

11. 11/29/2004RSNA 200411 PUBLICATION BIAS

12. 11/29/2004RSNA 200412 TECHNOLOGICAL EVOLUTION USING PUBLICATION YEAR (1992-2004) AS SURROGATE MEASURE OF TECHNOLOGICAL EVOLUTION IN A CUMMULATIVE META- ANALYSIS SHOWS THAT EARLIER STUDIES REPORTED MORE OPTIMISTIC RESULTS

13. 11/29/2004RSNA 200413 CONCLUSIONS The pooled evidence & corresponding clinically- relevant measures from SROC analysis show excellent specificity and moderate likelihood ratios for axillary FDG-PET The levels of discriminatory performance and informativeness do not obviate surgical staging in a large number of patients Adequately powered, methodologically sound, multicenter (comparative SLNMB-PET) studies using relevant clinical spectrum are warranted.