Evaluation of FLT-PET-CT as an imaging biomarker of proliferation in primary breast cancer.
BACKGROUND
[(18)F]fluorothymidine (FLT) has been proposed as a positron emission tomography (PET)-imaging biomarker of proliferation for breast cancer. The aim of this prospective study was to assess the feasibility of FLT-PET-CT as a technique for predicting the response to neoadjuvant chemotherapy (NAC) in primary breast cancer and to compare baseline FLT with Ki-67.


METHODS
Twenty women with primary breast cancer had a baseline FLT-PET-CT scan that was repeated before the second cycle of chemotherapy. Expression of Ki-67 in the diagnostic biopsy was quantified. From the FLT-PET-CT scans lesion maximum and mean standardised uptake values (SUVmax, SUVmean) were calculated.


RESULTS
Mean baseline SUVmax was 7.3, and 4.62 post one cycle of NAC, representing a drop of 2.68 (36.3%). There was no significant association between baseline, post chemotherapy, or change in SUVmax and pathological response to NAC. There was a significant correlation between pre-chemotherapy Ki-67 and SUVmax of 0.604 (P=0.006).


CONCLUSIONS
Baseline SUVmax measurements of FLT-PET-CT were significantly related to Ki-67 suggesting that it is a proliferation biomarker. However, in this series neither the baseline value nor the change in SUVmax after one cycle of NAC were able to predict response as most patients had a sizeable SUVmax reduction.
Breast Research Unit, Mount Vernon Cancer Centre, Rickmansworth Road, Northwood, HA6 2RN, UK.
D K
DK
Woolf
Department of Oncology, Royal United Hospital Bath, Avon, Bath, BA1 3NG, UK.
M
M
Beresford
Breast Research Unit, Mount Vernon Cancer Centre, Rickmansworth Road, Northwood, HA6 2RN, UK.
S P
SP
Li
Academic Department of Biochemistry, Royal Marsden Hospital, Fulham Road, London, SW3 6JJ, UK.
M
M
Dowsett
Paul Strickland Scanner Centre, Mount Vernon Hospital, Rickmansworth Road, Northwood, HA6 2RN, UK.
B
B
Sanghera
Paul Strickland Scanner Centre, Mount Vernon Hospital, Rickmansworth Road, Northwood, HA6 2RN, UK.
W L
WL
Wong
Paul Strickland Scanner Centre, Mount Vernon Hospital, Rickmansworth Road, Northwood, HA6 2RN, UK.
L
L
Sonoda
Academic Department of Biochemistry, Royal Marsden Hospital, Fulham Road, London, SW3 6JJ, UK.
S
S
Detre
Breast Research Unit, Mount Vernon Cancer Centre, Rickmansworth Road, Northwood, HA6 2RN, UK.
V
V
Amin
Breast Research Unit, Mount Vernon Cancer Centre, Rickmansworth Road, Northwood, HA6 2RN, UK.
M-L
ML
Ah-See
Breast Research Unit, Mount Vernon Cancer Centre, Rickmansworth Road, Northwood, HA6 2RN, UK.
D
D
Miles
Breast Research Unit, Mount Vernon Cancer Centre, Rickmansworth Road, Northwood, HA6 2RN, UK.
A
A
Makris
D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000627:therapeutic use; D014408:Biomarkers, Tumor / Q000096:biosynthesis; D001943:Breast Neoplasms / Q000188:drug therapy / Q000473:pathology* / Q000601:surgery; D049109:Cell Proliferation; D015224:Dideoxynucleosides; D005260:Female; D006801:Humans; D019394:Ki-67 Antigen / Q000096:biosynthesis; D008408:Mastectomy; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D049268:Positron-Emission Tomography / Q000379:methods*; D011446:Prospective Studies; D019275:Radiopharmaceuticals
D000970:Antineoplastic Agents; D014408:Biomarkers, Tumor; D015224:Dideoxynucleosides; D019394:Ki-67 Antigen; D019275:Radiopharmaceuticals; C002854:alovudine