Abstract P5-12-05: Clinical outcomes in early breast cancer patients on adjuvant tamoxifen: Impact of CYP2D6 genotype and observed endoxifen concentrations
Notice bibliographique
Résumé
Abstract Background: Tamoxifen is widely used in patients with hormone sensitive breast cancer in the adjuvant setting to decrease risk of recurrence and metastasis. 5-10 years of tamoxifen has demonstrated a near 50% reduction in recurrence risk. Despite marked interpatient variation in the metabolism of tamoxifen to its active metabolite endoxifen, all patients are prescribed 20 mg daily dose of tamoxifen. Current evidence suggests that patients are at risk for suboptimal benefit if measured endoxifen concentration is below 5.9 ng/ml (~15nM). However, there have been conflicting data on the clinical utility of CYP2D6 genotype testing, and measuring endoxifen plasma concentration as a predictor of breast cancer recurrence. The goal of this prospective study was to determine the impact of endoxifen levels and CYP2D6 genetic variations to clinical outcome among patients with early breast cancer. Methods: Since 2010, as part of Personalized Medicine Program in Oncology, our team has been prospectively enrolling patients on tamoxifen therapy. To date 950 patients have been enrolled and preliminary analysis has been completed in 429. After initial CYP2D6 genotype testing, plasma concentration of tamoxifen and its metabolites were quantified using liquid chromatography-tandem mass spectrometry during each clinic visit. Baseline characteristic are outlined in table 1. Primary outcome assessed was invasive disease-free survival (IDFS) defined as time since start of tamoxifen therapy till an event of interest such as loco-regional recurrence, distant metastasis, new contralateral primary breast cancer, death due to breast cancer and other causes. Patients were censored at their last encounter at our institution (London Health Sciences Centre). Results: IDFS data for 426 patients were obtained. Outcome was stratified by CYP2D6 phenotypes (ultra-rapid, extensive, intermediate and poor metabolizers) and endoxifen levels (>5.9ng/ml or <5.9ng/ml). CYP2D6 phenotype did not demonstrate a significant association for IDFS. However, Kaplan Meier analysis stratified for endoxifen concentration >vs< 5.9 ng/ml showed a clear trend towards lower IDFS (hazard ratio = 2.4, (95%CI,1.26-4.77) P=0.0002) among those with endoxifen < 5.9 ng/ml. We note this preliminary data analysis was unadjusted and will undergo further in-depth statistical analysis. Conclusion: Preliminary finding suggests endoxifen concentration, but not CYP2D6 phenotype, may be a predictor of risk for suboptimal benefit during tamoxifen therapy. Detailed statistical analysis is planned for the full cohort, including adjustment for covariates including tumor stage, menopausal status, drug interactions, and use of aromatase inhibitors. To our knowledge, this is the first study of its type to prospectively collect multiple plasma samples for tamoxifen and endoxifen level in real-world patients during tamoxifen therapy, with sufficient sample size and follow-up period for primary clinical outcome. Table 1: Baseline Characteristics of PatientsCharacteristicsCYP2D6-Phenotypes, n=429 (%)Endoxifen concentration, n=429 (%)UM/EMIMPM>5.9ng/ml(~15nm)<5.9ng/ml(~15nm)n= 256n= 153n= 20n=376n= 53Age at DiagnosisMean5049485048Range24-8928-7928-8324-8427-88SexMale3 (1)7(5)08(2)2(4)Female253 (99)146(95)20(100)368(98)51(96)Tumor statusT1121(47)70(46)9(45)177(47)23(43)T297(38)58(38)10(50)142(38)23(43)T318(7)16(10)1(5)30(8)5(9)T412(5)4(3)016(4)0unknown8(3)5(3)011(3)2(4)Nodal statusN0124(97)71(46)10(50)179(48)26(49)N195 (37)53(35)9(45)144(38)13(24)N217(7)18(12)1(5)28(7)8(15)N313(5)5(3)015(4)3(6)Unknown7(3)6(4)010(3)3(6)HistologyIDC205(80)128(84)16(80)303(81)48(91)ILC28(11)14(9)3(15)41(11)3(6)other5(2)2(1)06(2)0unknown18(7)9(6)1(5)26(7)2(4)Grade154(21)24(16)3(15)78(21)3(6)2139(54)84(55)13(65)202(54)34(64)354(21)39(25)4(20)84(3)13(24)unknown9(4)6(4)012(3)3(6)ER+251(98)151(99)20(100)369(98)53(100)-5(2)2(1)07(2)0unknown00000PR+232(90)142(93)20(100)343(91)51(96)-24(9)11(7)033(9)2(4)unknown00000Her2+55(21)25(16)5(25)75(20)10(19)-200(78)127(84)15(75)299(80)43(81)unknown1102(1)0Breast SurgeryMastectomy149(58)84(55)11(55)214(57)30(57)Lumpectomy105(41)68(44)9(45)159(42)23(43)Unknown2(1)103(1)0Axillary SurgerySLNB137(54)80(52)12(60)204(54)25(47)ALND113(44)70(46)8(40)165(44)26(49)Unknown6(2)3(2)07(2)2(4)Chemotherapy190(74)108(71)16(80)277(74)37(70)Radiation Therapy213(83)126(82)17(85)310(82)46(87)Herceptin57(22)23(15)6(30)77(16)9(17) Citation Format: Veera Durga Sravanthi Panuganty, Denise Keller, Wendy A Teft, John Gordon Lenehan, Kylea Raijann Potvin, Jawaid Younus, Theodorus Anthony Vandenberg, Diane Mary Logan, Karin Hahn, Muriel Brackstone, Phillip Stanley Blanchette, Francisco Perera, Yun-Hee Choi, Richard Brian Kim. Clinical outcomes in early breast cancer patients on adjuvant tamoxifen: Impact of CYP2D6 genotype and observed endoxifen concentrations [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P5-12-05.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,001 | 0,001 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,001 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,001 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,001 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,004 | 0,001 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».