Early metabolic response using FDG PET/CT and molecular phenotypes of breast cancer treated with neoadjuvant chemotherapy.
BACKGROUND
This study was aimed 1) to investigate the predictive value of FDG PET/CT (fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography) for histopathologic response and 2) to explore the results of FDG PET/CT by molecular phenotypes of breast cancer patients who received neoadjuvant chemotherapy.


METHODS
Seventy-eight stage II or III breast cancer patients who received neoadjuvant docetaxel/doxorubicin chemotherapy were enrolled in this study. FDG PET/CTs were acquired before chemotherapy and after the first cycle of chemotherapy for evaluating early metabolic response.


RESULTS
The mean pre- and post-chemotherapy standard uptake value (SUV) were 7.5 and 3.9, respectively. The early metabolic response provided by FDG PET/CT after one cycle of neoadjuvant chemotherapy was correlated with the histopathologic response after completion of neoadjuvant chemotherapy (P = 0.002). Sensitivity and negative predictive value were 85.7% and 95.1%, respectively. The estrogen receptor negative phenotype had a higher pre-chemotherapy SUV (8.6 vs. 6.4, P = 0.047) and percent change in SUV (48% vs. 30%, P = 0.038). In triple negative breast cancer (TNBC), the pre-chemotherapy SUV was higher than in non-TNBC (9.8 vs. 6.4, P = 0.008).


CONCLUSIONS
The early metabolic response using FDG PET/CT could have a predictive value for the assessment of histopathologic non-response of stage II/III breast cancer treated with neoadjuvant chemotherapy. Our findings suggest that the initial SUV and the decline in SUV differed based on the molecular phenotype.
Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
Bhumsuk
B
Keam
Seock-Ah
SA
Im
Youngil
Y
Koh
Sae-Won
SW
Han
Do-Youn
DY
Oh
Nariya
N
Cho
Jee Hyun
JH
Kim
Wonshik
W
Han
Keon Wook
KW
Kang
Woo Kyung
WK
Moon
Tae-You
TY
Kim
In Ae
IA
Park
Dong-Young
DY
Noh
June-Key
JK
Chung
Yung-Jue
YJ
Bang
D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000627:therapeutic use; D014408:Biomarkers, Tumor / Q000378:metabolism; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000378:metabolism; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008875:Middle Aged; D064847:Multimodal Imaging; D020360:Neoadjuvant Therapy; D009367:Neoplasm Staging; D010641:Phenotype; D049268:Positron-Emission Tomography; D014057:Tomography, X-Ray Computed
D000970:Antineoplastic Agents; D014408:Biomarkers, Tumor; D019788:Fluorodeoxyglucose F18