It is generally accepted that stage I and II breast cancer does not require staging. Stage II is divided into stage IIA and stage IIB based on tumor size and whether it has spread to the axillary lymph nodes (the lymph nodes under the arm). In stage IIA, the cancer is either not larger than 2 centimeters and has spread to the axillary lymph nodes, or between 2 and 5 centimeters but has not spread to the axillary lymph nodes. In stage IIB, the cancer is either between 2 and 5 centimeters and has spread to the axillary lymph nodes, or larger than 5 centimeters but has not spread to the axillary lymph nodes. Whether axillae are involved is determinded by physical exam, nodal dissection or, more recently, by sentinel node scintigraphy or imaging and/or biopsy.
The sensitivity of PET to stage axillae is limited. A multicenter trial cast doubt on the early supportive studies, and more recent single-center trials performed in the era of sentinel lymph node mapping showed that, compared with sentinel lymph node biopsy, the sensitivity of FDG PET and PET/CT for axillary nodal metastases was as low as 20%–40%. Therefore, PET should not be used as an axillary staging modality
Lee JH, Rosen EL, Mankoff DA: The role of radiotracer imaging in the diagnosis and management of patients with breast cancer: Part 1–Overview, detection, and staging. J Nucl Med 50:569-581, 2009
Lovrics PJ, Chen V, Coates G, et al: A prospective evaluation of positron emission tomography scanning, sentinel lymph node biopsy, and standard axillary dissection for axillary staging in patients with early stage breast cancer. Ann Surg Oncol 11:846-853, 2004
David A. Mankoff and Jennifer M. Specht, University of Washington; Seattle Cancer Care Alliance, Seattle, WA William B. Eubank, University of Washington; Puget Sound Veterans Affairs Medical Center, Seattle, WA Larry Kessler, University of Washington, Seattle, WA [18F]Fluorodeoxyglucose Positron Emission Tomography–Computed Tomography in Breast Cancer: When… and When Not?
JCO April 20, 2012 vol. 30 no. 12 1252-1254
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