20O - Analysis of molecular scores for the prediction of distant recurrence according to body mass index and age at baseline

Date 08 May 2014
Event IMPAKT 2014
Session Best abstracts session
Presenter Ivana Sestak
Citation Annals of Oncology (2014) 25 (suppl_1): i8-i16. 10.1093/annonc/mdu066
Authors I. Sestak1, M. Dowsett2, S. Ferree3, F.L. Baehner4, J.W. Cowens3, S. Butler4, J. Cuzick1
  • 1Wolfson Institute Of Preventive Medicine, Queen Mary University, Centre for Cancer Prevention, EC1M6BQ - London/UK
  • 2Academic Biochemistry, Royal Marsden Hospital NHS Foundation Trust, SW3 6JJ - London/UK
  • 3Nanostring Technologies, NanoString Technologies, Seattle/US
  • 4Genomic Health, Genomic Health, Redwood City/US

Abstract

Background:

Many trials have now shown the benefit of an aromatase inhibitor in postmenopausal women with hormone receptor positive breast cancer. Several molecular profiles (Clinical Treatment Score (CTS), IHC4) and gene signatures (Oncotype DX Recurrence Score (RS), ROR score (Prosigna)) have been investigated for the prediction of (distant) recurrence in several trials and we have shown that these molecular markers significantly correlated with overall and also late distant recurrence. Here, we explore whether body mass index (BMI) and age affect the prediction of these molecular scores for distant recurrence in years 0–10 in the transATAC trial.

Methods:

940 postmenopausal women for whom all four scores were available were included in this analysis. Of these 865 (92.0%) had information on BMI and conventional BMI groups were used for the analysis (≤25, 25–30, >30 kg/m2). Age at entry was available for all women and was split into equal tertiles. The primary endpoint was distant recurrence. Cox proportional hazard models were used to determine the effect of a molecular score for the prediction of distant recurrence according to BMI and age group.

Results:

In this exploratory analysis, the CTS and ROR score added significant prognostic information in all three BMI groups, but tests for trend were not significant. The IHC4 provided most prognostic information in women with a BMI lower than 25 kg/m2. The RS did not add prognostic information for distant recurrence in women with a BMI of 30 kg/m2 or above, but a test for trend was non-significant. The effect size of the IHC4 and RS was strongest in women aged 59.8 years or younger. Trends tests for age were significant for the IHC4 and RS, but not for the CTS and ROR, for which most prognostic information was added in women aged 68 or older and those aged between 60 and 68, respectively. Further results for all scores in all patient sub-groups will be presented.

Conclusion:

Molecular scores are increasingly used in women with breast cancer to tailor individual treatment decisions. We have shown that the effect size of the molecular scores is different across age groups and some non-significant differences were found for BMI. Our results may be incorporated in the identification of women who may benefit most from the use of these molecular scores.

Disclosure:

M. Dowsett: Prof Dowsett has received grant support from and is on the speaker's bureau for AstraZeneca. He acts as an adviser to Genoptix.

S. Ferree: S. Ferree disclosed he is an employee of and shareholder in NanoString Technologies.

F.L. Baehner: Dr Baehner disclosed that he is an employee Genomic Health.

J. W. Cowens: Dr Cowens disclosed that he is an employee of and shareholder in Nano String Technologies.

S. Butler: Dr Butler disclosed that he is an employee of Genomic Health.

J. Cuzick: Prof Cuzick disclosed that he received grant support from and is on the speaker's bureau for AstraZeneca. All other authors have declared no conflicts of interest.