Impact of Pretreatment Combined (18)F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Staging on Radiation Therapy Treatment Decisions in Locally Advanced Breast Cancer.
OBJECTIVE
To assess the diagnostic performance of pretreatment (18)F-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) and its impact on radiation therapy treatment decisions in patients with locally advanced breast cancer (LABC).


METHODS
Patients with LABC with Eastern Cooperative Oncology Group performance status <2 and no contraindication to neoadjuvant chemotherapy, surgery, and adjuvant radiation therapy were enrolled on a prospective trial. All patients had pretreatment conventional imaging (CI) performed, including bilateral breast mammography and ultrasound, bone scan, and CT chest, abdomen, and pelvis scans performed. Informed consent was obtained before enrolment. Pretreatment whole-body (18)F-FDG PET/CT scans were performed on all patients, and results were compared with CI findings.


RESULTS
A total of 154 patients with LABC with no clinical or radiologic evidence of distant metastases on CI were enrolled. Median age was 49 years (range, 26-70 years). Imaging with PET/CT detected distant metastatic disease and/or locoregional disease not visualized on CI in 32 patients (20.8%). Distant metastatic disease was detected in 17 patients (11.0%): 6 had bony metastases, 5 had intrathoracic metastases (pulmonary/mediastinal), 2 had distant nodal metastases, 2 had liver metastases, 1 had pulmonary and bony metastases, and 1 had mediastinal and distant nodal metastases. Of the remaining 139 patients, nodal disease outside conventional radiation therapy fields was detected on PET/CT in 15 patients (10.8%), with involvement of ipsilateral internal mammary nodes in 13 and ipsilateral level 5 cervical nodes in 2.


CONCLUSIONS
Imaging with PET/CT provides superior diagnostic and staging information in patients with LABC compared with CI, which has significant therapeutic implications with respect to radiation therapy management. Imaging with PET/CT should be considered in all patients undergoing primary staging for LABC.
Peter MacCallum Cancer Centre, Melbourne, Australia. Electronic address: sweet.ng@petermac.org.
Sweet Ping
SP
Ng
Peter MacCallum Cancer Centre, Melbourne, Australia.
Steven
S
David
Monash Cancer Centre, Melbourne, Australia.
Muhammad
M
Alamgeer
Monash Cancer Centre, Melbourne, Australia.
Vinod
V
Ganju
D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents; D001859:Bone Neoplasms / Q000000981:diagnostic imaging / Q000556:secondary; D001842:Bone and Bones / Q000000981:diagnostic imaging; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000628:therapy; D003657:Decision Making; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008113:Liver Neoplasms / Q000000981:diagnostic imaging / Q000556:secondary; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000556:secondary; D008327:Mammography / Q000379:methods; D008408:Mastectomy; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods*; D020360:Neoadjuvant Therapy; D049268:Positron-Emission Tomography / Q000379:methods*; D011446:Prospective Studies; D019275:Radiopharmaceuticals; D011878:Radiotherapy / Q000379:methods; D011879:Radiotherapy Dosage; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014463:Ultrasonography
D000970:Antineoplastic Agents; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18