Oops, you're using an old version of your browser so some of the features on this page may not be displaying properly.

MINIMAL Requirements: Google Chrome 24+Mozilla Firefox 20+Internet Explorer 11Opera 15–18Apple Safari 7SeaMonkey 2.15-2.23

Mini Oral - Breast cancer, early stage

167MO - Longitudinal evaluation of serum assessed non-adherence to tamoxifen (TAM) among premenopausal patients (pts) in the prospective multicenter CANTO cohort


18 Sep 2020


Mini Oral - Breast cancer, early stage


Tumour Site

Breast Cancer


Barbara Pistilli


Annals of Oncology (2020) 31 (suppl_4): S303-S339. 10.1016/annonc/annonc267


B. Pistilli1, A.R. Ferreira2, D. Combarel3, A. Paci4, J. Havas5, C. Pradon6, A. Bardet7, A. Di Meglio8, G. Menvielle9, L. FASSE10, P.H. Cottu11, F. Lerebours12, C. Coutant13, A. LESUR14, N. Chopin15, S. Everhard16, S. Delaloge17, S. Michiels18, F. André19, I. Vaz Luis20

Author affiliations

  • 1 Breast Cancer Group, Institut Gustave Roussy, 94805 - Villejuif/FR
  • 2 Department Of Medical Oncology, Champalimaud Foundation Cancer Center, 1400-038 - Lisbon/PT
  • 3 Pharmacology, Institut Gustave Roussy, 94800 - Villejuif/FR
  • 4 Pharmacology, Institut Gustave Roussy, 94805 - Villejuif/FR
  • 5 Unit U 981, Gustave Roussy, INSERM, 94405 - Villejuif/FR
  • 6 Et-extra- Centre Of Biology Resources, Institut Gustave Roussy, 94800 - Villejuif/FR
  • 7 Team Oncostat, Cesp, Institut Gustave Roussy, 94805 - Villejuif/FR
  • 8 Survivorship Program-inserm Umr 981, Institut Gustave Roussy, 94405 - Villejuif/FR
  • 9 Inserm, Institut Pierre Louis D’epidémiologie Et De Santé Publique (iplesp Umrs 1136), Sorbonne Université, 75012 - Paris/FR
  • 10 Psychoncology Unit, Institut Gustave Roussy, 94800 - Villejuif/FR
  • 11 Medical Oncology, Institut Curie, 75005 - Paris/FR
  • 12 Institut Curie, Department of Medical Oncology, Institut Curie, 26 rue d’Ulm, 75005 Paris &, 75005 - Paris et Saint-Cloud/FR
  • 13 Department Of Medical Oncology, Centre Georges-François Leclerc, Dijon/FR
  • 14 Department Of Medical Oncology, Institut de Cancerologie de Lorraine, 54159 - Nancy/FR
  • 15 Surgery Department, Centre Leon Berard, 69008 - Lyon/FR
  • 16 Ucbg, UNICANCER, 75654 - Paris/FR
  • 17 Breast Oncology Department, Institut Gustave Roussy, 94805 - Villejuif/FR
  • 18 Team Oncostat, Cesp, Gustave Roussy, 94805 - Villejuif/FR
  • 19 Breast Cancer Unit, Medical Oncology Department, Gustave Roussy - Cancer Campus, 94805 - Villejuif/FR
  • 20 Survivorship Program- Inserm Umr 981, Institut Gustave Roussy, 94405 - Villejuif/FR


Login to access the resources on OncologyPRO.

If you do not have an ESMO account, please create one for free.

Abstract 167MO


Using TAM serum assessment, we demonstrated that 1 in 6 premenopausal pts with early breast cancer (EBC) are non-adherent to TAM at 1 year (Y1) from treatment initiation. Most of them did not overtly declare non-adherence. We now evaluate the longitudinal evolution of non-adherence to TAM by using serum assessment and pts’ self-declarations at year 3 (Y3).


CANTO COMPLETE, a sub-study of CANTO cohort (NCT01993498), evaluates prevalence and predictors of non-adherence to adjuvant endocrine therapy in premenopausal pts at several time points from treatment initiation by drug serum levels and pts’ self-declarations. TAM was measured by liquid chromatography-tandem mass spectrometry on 50 μL of serum (lower limit of quantification [LLOQ]= 10 ng/mL). Pts were considered as biochemically non-adherent if TAM <60 ng/mL. Pts’ declarations were collected at the same time points. We used multivariable logistic regression and longitudinal multivariable mixed models to evaluate non-adherence at Y3.


718 pts were evaluable at Y3. Median age 46 (IQR 42–49), partnered 536 (78.7%), post-graduation education 362 (52.6%), stage I BC 333 (46.4%) and received chemotherapy 444 (61.8%). At Y3, serum assessment showed that 260 (36.2%) pts were non-adherent, of whom 226 (31.5%) with TAM Definition TAM at Y1 (ng/mL) TAM at Y3 (ng/mL) N pts (%) * Early discontinuation <60 <60 83 (13.1) Later discontinuation ≥60 <60 144 (22.8) Interruption <60 ≥60 14 (2.2) Persistence ≥60 ≥60 392 (61.9)

*85 missing at Y1


At Y3 from initiation of TAM, more than 1 patient out of 3 was poorly adherent to adjuvant TAM, showing that non-adherence sharply increased from Y1 to Y3. Serum assessment was able to identify a higher proportion of pts who have dropped out from treatment early.

Clinical trial identification


Editorial acknowledgement

Legal entity responsible for the study



Institut National Cancer-France grant (SHS-E-SP 18-129) to Barbara Pistilli, a Career Catalyst Research grant from Susan G. Komen (CCR17483507) to Ines Vaz-Luis, a Fondation ARC pour la recherche sur le cancer grant (CANTO-WORK-programme labillisé) to Ines Vaz-Luis and Gwenn Menvielle and the Philanthropic Odyssea Gustave Roussy Program. The CANTO study is supported by the French Government under the “Investment for the Future” program managed by the National Research Agency (ANR), grant n° ANR-10-COHO-0004.


B. Pistilli: Honoraria (institution), Advisory/Consultancy: Puma Biotechnology; Speaker Bureau/Expert testimony: Pierre Fabre; Honoraria (institution), Advisory/Consultancy, Speaker Bureau/Expert testimony, Travel/Accommodation/Expenses: Novartis; Speaker Bureau/Expert testimony: Myriad Genetics; Travel/Accommodation/Expenses: MSD Oncology; Honoraria (institution), Travel/Accommodation/Expenses: AstraZeneca; Honoraria (institution), Travel/Accommodation/Expenses: Pfizer; Honoraria (institution): Merus. A.R. Ferreira: Advisory/Consultancy, Travel/Accommodation/Expenses: Roche; Advisory/Consultancy, Travel/Accommodation/Expenses: Novartis. A. Bardet: Advisory/Consultancy: Roche SAS. P.H. Cottu: Honoraria (self), Travel/Accommodation/Expenses: Pfizer; Honoraria (self), Honoraria (institution), Travel/Accommodation/Expenses: Roche; Honoraria (self): Lilly; Honoraria (institution): Novartis. S. Michiels: Advisory/Consultancy: IDDI; Advisory/Consultancy: Janssen Cilag; Speaker Bureau/Expert testimony: Hexal; Speaker Bureau/Expert testimony: Steba; Speaker Bureau/Expert testimony: IQVIA; Speaker Bureau/Expert testimony: Roche; Speaker Bureau/Expert testimony: Sensorion; Speaker Bureau/Expert testimony: Biophytis; Speaker Bureau/Expert testimony: Servier; Speaker Bureau/Expert testimony: Yuhan. I. Vaz Luis: Speaker Bureau/Expert testimony: Novartis; Speaker Bureau/Expert testimony: Amgen; Speaker Bureau/Expert testimony: AstraZeneca; Advisory/Consultancy: Kephren. All other authors have declared no conflicts of interest.

This site uses cookies. Some of these cookies are essential, while others help us improve your experience by providing insights into how the site is being used.

For more detailed information on the cookies we use, please check our Privacy Policy.

Customise settings
  • Necessary cookies enable core functionality. The website cannot function properly without these cookies, and you can only disable them by changing your browser preferences.