Value of fourth and subsequent post-therapy follow-up 18F-FDG PET/CT scans in patients with breast cancer.
OBJECTIVE
To evaluate the accuracy and value of the fourth and subsequent post-therapy follow-up fluorine-18 fluorodeoxyglucose (F-FDG) PET/computed tomography (CT) scans in the clinical assessment of breast cancer patients.


METHODS
Ninety-two female patients, with a total of 426 fourth and subsequent follow-up PET/CT scans, were retrospectively included. Patients were followed for a median of 23.7 months (range, 0.7-124.4) from the fourth follow-up PET/CT. The diagnostic accuracy of PET/CT, its impact on clinical assessment, patients' management, and survival outcome were established.


RESULTS
Of the 426 follow-up PET/CT scans, 264 (62%) were interpreted as positive and 162 (38%) were interpreted as negative. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the fourth and subsequent follow-up PET/CT scans were 97.7, 98.1, 98.8, 96.3, and 97.9%, respectively. Fourth and subsequent follow-up PET/CT were useful in excluding a tumor in 13.4% (39/292) of patients with a clinical suspicion of recurrence and identifying suspected recurrence in 10.5% (14/134) of patients without previous clinical suspicion. A change in management was noted in 6.7% (9/134) of scan times when the scans were performed without previous clinical suspicion of recurrence or therapy response and was 27.7% (81/292) when the scans were performed with clinical suspicion. Overall survival differed significantly between patients with all negative follow-up scans (n=23) and those who had at least one positive follow-up scan (n=69) (hazard ratio of 4.65, P<0.001).


CONCLUSIONS
The fourth and subsequent PET/CT scans performed after the completion of primary treatment led to a change in management in 27.7% of patients when the scans were performed with clinical suspicion and only in 6.7% of patients when performed without clinical suspicion or context.
aRussell H Morgan Department of Radiology and Radiological SciencesbDepartment of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins School of MedicinecDepartment of Health Policy and Management, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA.
Mehdi
M
Taghipour
Sara
S
Sheikhbahaei
Tyler J
TJ
Trahan
Rathan M
RM
Subramaniam
D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000401:mortality / Q000628:therapy*; D018572:Disease-Free Survival; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008137:Longitudinal Studies; D008396:Maryland / Q000453:epidemiology; D008875:Middle Aged; D000072078:Positron Emission Tomography Computed Tomography / Q000379:methods / Q000706:statistics & numerical data*; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012307:Risk Factors; D012680:Sensitivity and Specificity; D015996:Survival Rate; D016896:Treatment Outcome
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18