Early (18)F-2-fluoro-2-deoxy-d-glucose positron emission tomography may identify a subset of patients with estrogen receptor-positive breast cancer who will not respond optimally to preoperative chemotherapy.
BACKGROUND
A pathologic complete response (pCR) and minimal residual disease (pMRD) after preoperative chemotherapy (PCT) for early stage or locally advanced breast cancer (BC) correlates with a good prognosis.


METHODS
Patients who received from 6 to 8 cycles of PCT for BC were monitored by (18)F-2-fluoro-2-deoxy-D-glucose positron emission tomography ((18)F-FDG-PET), and the maximal standardized uptake value (SUVmax) was calculated at baseline, after 2 cycles, after 4 cycles, and at the end of PCT. SUVmax percentage changes (Delta-SUV) were compared with the pathologic response rate. Patients who had a pCR or pMRD in the tumor and an absence of cancer cells in ipsilateral axillary lymph nodes were defined as having obtained an optimal pathologic response (pR), whereas all the other conditions were classified as a pathologic nonresponse (pNR).


RESULTS
Of 34 patients, 7 (21%) achieved a pR (3 patients had a pCR, and 4 patients had pMRD). After the second cycle, the Delta-SUV threshold with optimal negative predictive value to predict a pR was 50%. Twenty-six patients (76%) had a Delta-SUV >50%, including all 7 patients who had a pR and 19 patients who had a pNR. Conversely, all 8 patients who had a Delta-SUV < or =50% had a pNR. All 8 of those patients had estrogen recepetor-positive tumors.


CONCLUSIONS
Early evaluation of metabolic response by (18)F-FDG-PET during PCT was able to identify 30% of patients, all with estrogen receptor-positive tumors, who would not obtain pR after completion of chemotherapy program.
Martoni
Andrea A
AA
Medical Oncology Unit, S. Orsola-Malpighi University Hospital, via Albertoni 15, 40138 Bologna, Italy. andrea.martoni@aosp.bo.it
Zamagni
Claudio
C
Quercia
Sara
S
Rosati
Marta
M
Cacciari
Nicoletta
N
Bernardi
Alessandra
A
Musto
Alessandra
A
Fanti
Stefano
S
Santini
Donatella
D
Taffurelli
Mario
M
D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage*; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D017024:Chemotherapy, Adjuvant; D003131:Combined Modality Therapy; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D018365:Neoplasm, Residual; D009376:Neoplasms, Hormone-Dependent / Q000175:diagnosis* / Q000188:drug therapy; D049268:Positron-Emission Tomography; D011379:Prognosis; D011960:Receptors, Estrogen / Q000378:metabolism*; D016896:Treatment Outcome
D011960:Receptors, Estrogen; D019788:Fluorodeoxyglucose F18