• WIS Articles
• WIS Presentations
• Ask A Radiologist

Patient History

The patient is a 66 y/o female status post exploratory surgery of left axillary lymph nodes. Pathology showed a poorly differentiated breast carcinoma. The patient was sent for a PET/CT exam to assist in staging.

Staging with Conventional Techniques
Stage II, T1-N1-M0

PET/CT Images

PET/CT Findings
Extensive lymph node metastases from the patient’s poorly differentiated breast carcinoma, including bulky left axillary and retro-pectoral lymph nodes, small left supraclavicular, bilateral hilar, and mediastinal lymphadenopathy consistent with metastatic disease. A small focus of increased activity in the tail of the left breast also was noted, which may represent the patient’s primary tumor and/or post-procedural change. A moderately hypermetabolic area in the sigmoid colon was suspicious for metastases - later confirmed by biopsy.

Tissue Diagnosis
Metastatic Breast Carcinoma

New Clinical Stage after PET/CT
Stage IV

Sensitivity and Specificity

Medicare Recognizes PET/CT Utility in Breast Cancer

• Staging
• Restaging
• Monitoring therapy

Discussion

Common site of metastasis such as lymph nodes or bone marrow are not easily depicted by conventional imaging, resulting in misdiagnosis and inappropriate therapeutic intervention.¹

• 45% of women diagnosed with breast cancer will either have metastatic disease at the time of diagnosis or develop recurrent disease following localized treatment.²
• Conventional imaging modalities have limited ability to detect distant or regional disease when no disturbance in anatomy is present.³

Clinical Questions Answered

This scan demonstrates the utility of PET/CT for selected breast cancer cases. Although PET/CT is not appropriate for screening or diagnosis of primary breast disease, PET/CT is invaluable for staging patients with locally advanced breast carcinoma or carcinomas in the medial aspect of the breast. PET/CT provides more accurate staging information in these patients at higher risk for distant metastases than conventional imaging techniques. In addition, PET/CT has utility in bone-scan negative, bone-centric metastatic bone cancer, especially if it manifests with lytic bone disease. PET/CT differentiates chemotherapy responders from non-responders earlier than conventional imaging or physical examination in patients with locally advanced and/or metastatic breast cancer.⁵ This allows appropriate modifications of chemotherapy for improved response and prevention of chemotherapy related complications such as cardiomyopathy.

Points to Remember

• PET/CT REVEALS EXTENT OF DISTANT METASTASES WHILE ALSO EVALUATING THE PRIMARY SITE IN A SINGLE WHOLE-BODY SCAN.
• PET/CT CAN PLAY A CRITICAL ROLE IN MONITORING RESPONSE TO THERAPY
  • FUNCTIONAL CHANGES PRECEDE ANATOMIC CHANGES;
  • THEREFORE, EARLIER ASSESSMENT OF THERAPEUTIC RESPONSE IS ACHIEVABLE

1. Vranjesevic D, Filmont JE, Meta J, et al. Whole-body 18F-FDG PET and conventional imaging for predicting outcome in previously treated breast cancer patients. J Nucl Med. 2004;43:325-329.
2. Mortimer J, Dehdashti F, Siegel BA, et al. Metabolic flare: indicator of hormone responsiveness in advanced breast cancer. J Clin Oncol. 2001;19:2797-2803.
3. Conti P, Lilien D, Hawley K, Keppler J, Grafton S, Bading J. PET and [18F]-FDG in oncology: a clinical update. Nucl Med Biol. 2004;23;6:717-735.
4. Gambhir S, Czernin J, Schwimmer J, Silverman DHS, Coleman RE, Phelps ME. A tabulated summary of the FDG PET literature. J Nucl Med. 2001;42(suppl):1S-93S.
5. Schelling M, Avril N, Nährig J, et al. Positron emission tomography using [18F] fluorodeoxyglucose for monitoring primary chemotherapy in breast cancer. J Clin Oncol. 2000;18:1689-1694