Early assessment with 18F-fluorodeoxyglucose positron emission tomography/computed tomography can help predict the outcome of neoadjuvant chemotherapy in triple negative breast cancer.
BACKGROUND
In patients with triple-negative breast cancer (TNBC), pathology complete response (pCR) to neoadjuvant chemotherapy (NAC) is associated with improved prognosis. This prospective study was designed and powered to investigate the ability of interim (18)F-fluorodeoxyglucose positron emission tomography/computed tomography ((18)FDG-PET/CT) to predict pathology outcomes to NAC early during treatment.


METHODS
Consecutive TNBC women underwent (18)FDG-PET/CT at baseline and after two courses of NAC. Maximum standardised uptake value (SUV(max)) in the primary tumour and lymph nodes at each examination and the evolution (ΔSUV(max)) between the two scans were measured. NAC was continued irrespective of PET results. Correlations between PET parameters and pathology response, and between PET parameters and event-free survival (EFS), were examined.


RESULTS
Fifty patients without distant metastases were enroled. At completion of NAC, surgery showed pCR in 19 patients, while 31 had residual tumour. Mean follow-up was 30.3 months. Thirteen patients, all with residual tumour, experienced relapse. Of all assessed clinical, biological and PET parameters, ΔSUV(max) in the primary tumour was the most predictive of pathology results (p<0.0001; Mann-Whitney-U test) and EFS (p=0.02; log rank test). A threshold of 42% decrease in SUV was identified because it offered the best accuracy in predicting EFS. There were 32 metabolic responders (⩾ 42% decrease in SUV(max)) and 18 non-responders. Within responders, the pCR rate was 59% and the 3-year EFS 77.5%. In non-responders, the pCR rate was 0% and the 3-year EFS 47.1%.


CONCLUSIONS
Interim (18)FDG can early predict the inefficacy of NAC in TNBC patients. It shows promise as a potential contributory biomarker in these patients.
Department of Nuclear Medicine, Saint-Louis Hospital, Paris, France; B2T, Doctoral School, IUH, University of Paris VII, France. Electronic address: dgroheux@yahoo.fr.
David
D
Groheux
Department of Nuclear Medicine, CHU Bordeaux, University of Bordeaux, France.
Elif
E
Hindié
Breast Diseases Unit and Department of Medical Oncology, Saint-Louis Hospital, Paris, France.
Sylvie
S
Giacchetti
Breast Diseases Unit and Department of Medical Oncology, Saint-Louis Hospital, Paris, France; Department of Biostatistics, Institut Curie, Paris, France.
Anne-Sophie
AS
Hamy
Department of Biostatistics, Institut Curie, Paris, France.
Frederique
F
Berger
Department of Nuclear Medicine, Saint-Louis Hospital, Paris, France; B2T, Doctoral School, IUH, University of Paris VII, France.
Pascal
P
Merlet
Department of Pathology, Saint-Louis Hospital, Paris, France.
Anne
A
de Roquancourt
Department of Biochemistry, Saint-Louis Hospital, Paris, France.
Patricia
P
de Cremoux
Breast Diseases Unit and Department of Medical Oncology, Saint-Louis Hospital, Paris, France; Centre for Therapeutic Innovation, Saint Louis Hospital, Paris, France.
Michel
M
Marty
INSERM, UMR 1101 LaTIM, Brest, France.
Mathieu
M
Hatt
Breast Diseases Unit and Department of Medical Oncology, Saint-Louis Hospital, Paris, France.
Marc
M
Espié
D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D003520:Cyclophosphamide / Q000008:administration & dosage; D018572:Disease-Free Survival; D000077143:Docetaxel; D015251:Epirubicin / Q000008:administration & dosage; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007150:Immunohistochemistry; D064847:Multimodal Imaging / Q000379:methods; D020360:Neoadjuvant Therapy; D009367:Neoplasm Staging; D049268:Positron-Emission Tomography / Q000379:methods; D011237:Predictive Value of Tests; D011446:Prospective Studies; D019275:Radiopharmaceuticals; D043823:Taxoids / Q000008:administration & dosage; D014057:Tomography, X-Ray Computed / Q000379:methods; D016896:Treatment Outcome; D064726:Triple Negative Breast Neoplasms / Q000000981:diagnostic imaging* / Q000188:drug therapy* / Q000473:pathology / Q000601:surgery
D019275:Radiopharmaceuticals; D043823:Taxoids; D019788:Fluorodeoxyglucose F18; D000077143:Docetaxel; D015251:Epirubicin; D003520:Cyclophosphamide
(18)FDG-PET/CT; Metabolic response; Neoadjuvant chemotherapy; Prognosis; Triple negative breast cancer