FDG PET Imaging for Breast Cancer

PET/CT is approved by Medicare for staging, monitoring response to therapy, restaging and surveillance. Typically, PET/CT is used for staging after a positive sentinel node biopsy.

PET has been shown to be an accurate predictor of the outcome of chemotherapy as early as after the first cycle (1). PET can also play a role in monitoring response to neoadjuvant therapy prior to surgery.

1. Smith et al. “PET using FDG to predict the pathologic response of breast cancer to primary chemotherapy.” J Clin Onc Vol 18(8) April 2000 pp 1676-1688.

2004 Breast Cancer Statistics*

  • Estimated New Cases 217,440
  • Estimated New Deaths 40,580

*All cancer statistics obtained from the American Cancer Society’s Cancer Facts and Figures available at www.cancer.org.

Breast Cancer & FDG PET Imaging Statistics**

Table 1: Utility of PET Imaging in Breast Cancer Diagnosis (N=318)

  PET CT
Sensitivity 91% N/A
Specificity 93% N/A
PPV 100% N/A
NPV 80% N/A
Accuracy 95% N/A

For this patient population there was a 100% change in the way the physician managed the patient’s disease based on the results of the PET scan.

Table 2: Utility of PET Imaging in Breast Cancer Staging (N=2034)

  PET CT
Sensitivity 91% 63%
Specificity 88% 96%
PPV 76% 74%
NPV 97% 92%
Accuracy 90% 90%

For this patient population there was a 24% change in the way the physician managed the patient’s disease based upon the results of the PET scan.

Table 3: Utility of PET Imaging in Breast Cancer Diagnosis/Staging (N=65)

  PET CT
Sensitivity 75% N/A
Specificity 83% N/A
PPV 100% N/A
NPV N/A N/A
Accuracy 83% N/A

Table 4: Utility of PET Imaging in Breast Cancer Recurrence (N=977)

  PET CT
Sensitivity 80% 90%
Specificity 85% 96%
PPV 88% 93%
NPV 89% 98%
Accuracy 82% 89%

For this patient population there was a 40% change in the way the physician managed the patient’s disease based upon the results of the PET scan.

Table 5: Utility of PET Imaging in Monitoring Breast Cancer (N=269)

  PET CT
Sensitivity 81% N/A
Specificity 96% N/A
Accuracy 92% N/A

For this patient population there was a 40% change in the way the physician managed the patient’s disease based upon the results of the PET scan.

** Reprinted by permission of the Society of Nuclear Medicine from: Gambhir, Sanjiv S., Czernin, Johannes, Schwimmer, Judy, Silverman, Daniel H.S., Coleman, R. Edward, Phelps, Michael E. “A Tabulated Summary of the FDG PET Literature” J Nucl Med 2001 42: 1-93.

Case Study
Patient: 36yo female with newly diagnosed breast cancer. A lung lesion was seen on CT.PET/CT was ordered to stage the patient.

Results: PET/CT confirmed that the lung lesion was cancerous. PET/CT also found cancer in the spine. This area appeared normal on CT.

PET/CT upstaged the patient to stage IV. Because of the extent of disease, chemotherapy was determined to be the most appropriate therapy. This PET/CT scan was used as a baseline scan to compare with a scan after the first cycle of chemotherapy.