De-EscaLaTion of Aromatase Inhibitor Therapy: A Randomized Phase II Study of De-escalated Letrozole in Hormone Receptor-Positive Early Breast Cancer

Summary

This study is a randomized, open-label, phase II trial designed to evaluate whether alternate-day dosing of letrozole preserves antiproliferative activity compared with standard daily dosing in postmenopausal women with estrogen receptor-positive, HER2-negative breast cancer.

Timeline

Start

2026-09

Primary completion

2032-10

Completion

2032-12

Publications

• Background Ellis MJ, Coop A, Singh B, Mauriac L, Llombert-Cussac A, Janicke F, Miller WR, Evans DB, Dugan M, Brady C, Quebe-Fehling E, Borgs M. Letrozole is more effective neoadjuvant endocrine therapy than tamoxifen for ErbB-1- and/or ErbB-2-positive, estrogen receptor-positive primary breast cancer: evidence from a phase III randomized trial. J Clin Oncol. 2001 Sep 15;19(18):3808-16. doi: 10.1200/JCO.2001.19.18.3808.
• Background Serrano D, Gandini S, Thomas P, Crew KD, Kumar NB, Vornik LA, Lee JJ, Veronesi P, Viale G, Guerrieri-Gonzaga A, Lazzeroni M, Johansson H, D'Amico M, Guasone F, Spinaci S, Bertelsen BE, Mellgren G, Bedrosian I, Weber D, Castile T, Dimond E, Heckman-Stoddard BM, Szabo E, Brown PH, DeCensi A, Bonanni B. Efficacy of Alternative Dose Regimens of Exemestane in Postmenopausal Women With Stage 0 to II Estrogen Receptor-Positive Breast Cancer: A Randomized Clinical Trial. JAMA Oncol. 2023 May 1;9(5):664-672. doi: 10.1001/jamaoncol.2023.0089.
• Background Karagiannis GS, Pastoriza JM, Wang Y, Harney AS, Entenberg D, Pignatelli J, Sharma VP, Xue EA, Cheng E, D'Alfonso TM, Jones JG, Anampa J, Rohan TE, Sparano JA, Condeelis JS, Oktay MH. Neoadjuvant chemotherapy induces breast cancer metastasis through a TMEM-mediated mechanism. Sci Transl Med. 2017 Jul 5;9(397):eaan0026. doi: 10.1126/scitranslmed.aan0026.
• Background Verma C, Eremin JM, Robins A, Bennett AJ, Cowley GP, El-Sheemy MA, Jibril JA, Eremin O. Abnormal T regulatory cells (Tregs: FOXP3+, CTLA-4+), myeloid-derived suppressor cells (MDSCs: monocytic, granulocytic) and polarised T helper cell profiles (Th1, Th2, Th17) in women with large and locally advanced breast cancers undergoing neoadjuvant chemotherapy (NAC) and surgery: failure of abolition of abnormal treg profile with treatment and correlation of treg levels with pathological response to NAC. J Transl Med. 2013 Jan 15;11:16. doi: 10.1186/1479-5876-11-16.
• Background Lopes AD, Galdino NAL, Figueiredo AB, Brianese RC, Morais KLP, De Brot M, Osorio CABT, Teixeira-Carvalho A, Calsavara VF, Evangelista GFB, Alves NS, Makdissi FB, Sanches SM, Cordeiro de Lima VC, Carraro DM, Gollob KJ. Systemic immune mediators reflect tumour-infiltrating lymphocyte intensity and predict therapeutic response in triple-negative breast cancer. Immunology. 2023 Jun;169(2):229-241. doi: 10.1111/imm.13627. Epub 2023 Feb 20.
• Background Miceli R, Cao C, Maolanon NN, Jacobs R, Wu J, Orlandi R. Plasma Profile of Immune Determinants Predicts Pathological Complete Response in Locally Advanced Breast Cancer Patients: A Pilot Study. Clin Breast Cancer. 2022 Oct;22(7):705-714. doi: 10.1016/j.clbc.2022.05.007. Epub 2022 May 23.
• Background Bidard FC, Proudhon C, Pierga JY. Circulating tumor cells in breast cancer. Mol Oncol. 2016 Mar;10(3):418-30. doi: 10.1016/j.molonc.2016.01.001. Epub 2016 Jan 12.
• Background Massague J, Obenauf AC. Metastatic colonization by circulating tumour cells. Nature. 2016 Jan 21;529(7586):298-306. doi: 10.1038/nature17038.
• Background Dasgupta A, Lim AR, Ghajar CM. Circulating and disseminated tumor cells: harbingers or initiators of metastasis? Mol Oncol. 2017 Jan;11(1):40-61. doi: 10.1002/1878-0261.12022.
• Background Carter L, Rothwell DG, Mesquita B, Smowton C, Leong HS, Fernandez-Gutierrez F, Li Y, Burt DJ, Antonello J, Morrow CJ, Hodgkinson CL, Morris K, Priest L, Carter M, Miller C, Hughes A, Blackhall F, Dive C, Brady G. Molecular analysis of circulating tumor cells identifies distinct copy-number profiles in patients with chemosensitive and chemorefractory small-cell lung cancer. Nat Med. 2017 Jan;23(1):114-119. doi: 10.1038/nm.4239. Epub 2016 Nov 21.
• Background Smerage JB, Barlow WE, Hortobagyi GN, Winer EP, Leyland-Jones B, Srkalovic G, Tejwani S, Schott AF, O'Rourke MA, Lew DL, Doyle GV, Gralow JR, Livingston RB, Hayes DF. Circulating tumor cells and response to chemotherapy in metastatic breast cancer: SWOG S0500. J Clin Oncol. 2014 Nov 1;32(31):3483-9. doi: 10.1200/JCO.2014.56.2561. Epub 2014 Jun 2.
• Background Kalinich M, Bhan I, Kwan TT, Miyamoto DT, Javaid S, LiCausi JA, Milner JD, Hong X, Goyal L, Sil S, Choz M, Ho U, Kapur R, Muzikansky A, Zhang H, Weitz DA, Sequist LV, Ryan DP, Chung RT, Zhu AX, Isselbacher KJ, Ting DT, Toner M, Maheswaran S, Haber DA. An RNA-based signature enables high specificity detection of circulating tumor cells in hepatocellular carcinoma. Proc Natl Acad Sci U S A. 2017 Jan 31;114(5):1123-1128. doi: 10.1073/pnas.1617032114. Epub 2017 Jan 17.
• Background Rack B, Schindlbeck C, Juckstock J, Andergassen U, Hepp P, Zwingers T, Friedl TW, Lorenz R, Tesch H, Fasching PA, Fehm T, Schneeweiss A, Lichtenegger W, Beckmann MW, Friese K, Pantel K, Janni W; SUCCESS Study Group. Circulating tumor cells predict survival in early average-to-high risk breast cancer patients. J Natl Cancer Inst. 2014 May 15;106(5):dju066. doi: 10.1093/jnci/dju066.
• Background Edge SB, Compton CC. The American Joint Committee on Cancer: the 7th edition of the AJCC cancer staging manual and the future of TNM. Ann Surg Oncol. 2010 Jun;17(6):1471-4. doi: 10.1245/s10434-010-0985-4.
• Background Hayes DF, Cristofanilli M, Budd GT, Ellis MJ, Stopeck A, Miller MC, Matera J, Allard WJ, Doyle GV, Terstappen LW. Circulating tumor cells at each follow-up time point during therapy of metastatic breast cancer patients predict progression-free and overall survival. Clin Cancer Res. 2006 Jul 15;12(14 Pt 1):4218-24. doi: 10.1158/1078-0432.CCR-05-2821.
• Background Bidard FC, Peeters DJ, Fehm T, Nole F, Gisbert-Criado R, Mavroudis D, Grisanti S, Generali D, Garcia-Saenz JA, Stebbing J, Caldas C, Gazzaniga P, Manso L, Zamarchi R, de Lascoiti AF, De Mattos-Arruda L, Ignatiadis M, Lebofsky R, van Laere SJ, Meier-Stiegen F, Sandri MT, Vidal-Martinez J, Politaki E, Consoli F, Bottini A, Diaz-Rubio E, Krell J, Dawson SJ, Raimondi C, Rutten A, Janni W, Munzone E, Caranana V, Agelaki S, Almici C, Dirix L, Solomayer EF, Zorzino L, Johannes H, Reis-Filho JS, Pantel K, Pierga JY, Michiels S. Clinical validity of circulating tumour cells in patients with metastatic breast cancer: a pooled analysis of individual patient data. Lancet Oncol. 2014 Apr;15(4):406-14. doi: 10.1016/S1470-2045(14)70069-5. Epub 2014 Mar 11.
• Background Cristofanilli M, Budd GT, Ellis MJ, Stopeck A, Matera J, Miller MC, Reuben JM, Doyle GV, Allard WJ, Terstappen LW, Hayes DF. Circulating tumor cells, disease progression, and survival in metastatic breast cancer. N Engl J Med. 2004 Aug 19;351(8):781-91. doi: 10.1056/NEJMoa040766.
• Background Roussos ET, Goswami S, Balsamo M, Wang Y, Stobezki R, Adler E, Robinson BD, Jones JG, Gertler FB, Condeelis JS, Oktay MH. Mena invasive (Mena(INV)) and Mena11a isoforms play distinct roles in breast cancer cell cohesion and association with TMEM. Clin Exp Metastasis. 2011 Aug;28(6):515-27. doi: 10.1007/s10585-011-9388-6. Epub 2011 Apr 12.
• Background Borriello L, Coste A, Traub B, Sharma VP, Karagiannis GS, Lin Y, Wang Y, Ye X, Duran CL, Chen X, Friedman M, Sosa MS, Sun D, Dalla E, Singh DK, Oktay MH, Aguirre-Ghiso JA, Condeelis JS, Entenberg D. Primary tumor associated macrophages activate programs of invasion and dormancy in disseminating tumor cells. Nat Commun. 2022 Feb 2;13(1):626. doi: 10.1038/s41467-022-28076-3.
• Background Pignatelli J, Goswami S, Jones JG, Rohan TE, Pieri E, Chen X, Adler E, Cox D, Maleki S, Bresnick A, Gertler FB, Condeelis JS, Oktay MH. Invasive breast carcinoma cells from patients exhibit MenaINV- and macrophage-dependent transendothelial migration. Sci Signal. 2014 Nov 25;7(353):ra112. doi: 10.1126/scisignal.2005329.
• Background Parmar P, Karadal-Ferrena B, Shukla S, Miller A, Zhang C, Huang C, D'Alfonso T, Han R, Adler E, Ladak N, Ginter PS, Fineberg S, Ye X, Ginsberg M, Rosenbaum C, Felder M, Lin Y, Chen X, Eddy RJ, Rohan TE, Condeelis JS, Xue X, Anampa J, Sparano JA, Entenberg D, Oktay MH. Racial disparity in pro-metastatic tumor microenvironment in treatment naive breast cancer. NPJ Breast Cancer. 2026 Jan 6;12(1):3. doi: 10.1038/s41523-025-00865-1.
• Background Kim G, Karadal-Ferrena B, Qin J, Sharma VP, Oktay IS, Lin Y, Ye X, Asiry S, Pastoriza JM, Cheng E, Ladak N, Condeelis JS, Adler E, Ginter PS, D'Alfonso T, Entenberg D, Xue X, Sparano JA, Oktay MH. Racial disparity in tumor microenvironment and distant recurrence in residual breast cancer after neoadjuvant chemotherapy. NPJ Breast Cancer. 2023 Jun 13;9(1):52. doi: 10.1038/s41523-023-00547-w.
• Background Sparano JA, Gray R, Oktay MH, Entenberg D, Rohan T, Xue X, Donovan M, Peterson M, Shuber A, Hamilton DA, D'Alfonso T, Goldstein LJ, Gertler F, Davidson NE, Condeelis J, Jones J. A metastasis biomarker (MetaSite Breast Score) is associated with distant recurrence in hormone receptor-positive, HER2-negative early-stage breast cancer. NPJ Breast Cancer. 2017 Nov 8;3:42. doi: 10.1038/s41523-017-0043-5. eCollection 2017.
• Background Harney AS, Arwert EN, Entenberg D, Wang Y, Guo P, Qian BZ, Oktay MH, Pollard JW, Jones JG, Condeelis JS. Real-Time Imaging Reveals Local, Transient Vascular Permeability, and Tumor Cell Intravasation Stimulated by TIE2hi Macrophage-Derived VEGFA. Cancer Discov. 2015 Sep;5(9):932-43. doi: 10.1158/2159-8290.CD-15-0012. Epub 2015 Aug 12.
• Background Gan Y, Lo Y, Makower D, Kleer C, Lu J, Fineberg S. EZH2 Protein Expression in Estrogen Receptor Positive Invasive Breast Cancer Treated With Neoadjuvant Endocrine Therapy: An Exploratory Study of Association With Tumor Response. Appl Immunohistochem Mol Morphol. 2022 Oct 1;30(9):614-622. doi: 10.1097/PAI.0000000000001055. Epub 2022 Sep 2.
• Background Guo S, Li X, Rohr J, Wang Y, Ma S, Chen P, Wang Z. EZH2 overexpression in different immunophenotypes of breast carcinoma and association with clinicopathologic features. Diagn Pathol. 2016 Apr 26;11:41. doi: 10.1186/s13000-016-0491-5.
• Background Anwar T, Gonzalez ME, Kleer CG. Noncanonical Functions of the Polycomb Group Protein EZH2 in Breast Cancer. Am J Pathol. 2021 May;191(5):774-783. doi: 10.1016/j.ajpath.2021.01.013. Epub 2021 Feb 6.
• Background Chang CJ, Hung MC. The role of EZH2 in tumour progression. Br J Cancer. 2012 Jan 17;106(2):243-7. doi: 10.1038/bjc.2011.551. Epub 2011 Dec 20.
• Background Goswami S, Sahai E, Wyckoff JB, Cammer M, Cox D, Pixley FJ, Stanley ER, Segall JE, Condeelis JS. Macrophages promote the invasion of breast carcinoma cells via a colony-stimulating factor-1/epidermal growth factor paracrine loop. Cancer Res. 2005 Jun 15;65(12):5278-83. doi: 10.1158/0008-5472.CAN-04-1853.
• Background Sharma VP, Tang B, Wang Y, Duran CL, Karagiannis GS, Xue EA, Entenberg D, Borriello L, Coste A, Eddy RJ, Kim G, Ye X, Jones JG, Grunblatt E, Agi N, Roy S, Bandyopadhyaya G, Adler E, Surve CR, Esposito D, Goswami S, Segall JE, Guo W, Condeelis JS, Wakefield LM, Oktay MH. Live tumor imaging shows macrophage induction and TMEM-mediated enrichment of cancer stem cells during metastatic dissemination. Nat Commun. 2021 Dec 15;12(1):7300. doi: 10.1038/s41467-021-27308-2.
• Background Robinson BD, Sica GL, Liu YF, Rohan TE, Gertler FB, Condeelis JS, Jones JG. Tumor microenvironment of metastasis in human breast carcinoma: a potential prognostic marker linked to hematogenous dissemination. Clin Cancer Res. 2009 Apr 1;15(7):2433-41. doi: 10.1158/1078-0432.CCR-08-2179. Epub 2009 Mar 24.
• Background Roussos ET, Balsamo M, Alford SK, Wyckoff JB, Gligorijevic B, Wang Y, Pozzuto M, Stobezki R, Goswami S, Segall JE, Lauffenburger DA, Bresnick AR, Gertler FB, Condeelis JS. Mena invasive (MenaINV) promotes multicellular streaming motility and transendothelial migration in a mouse model of breast cancer. J Cell Sci. 2011 Jul 1;124(Pt 13):2120-31. doi: 10.1242/jcs.086231.
• Background Philippar U, Roussos ET, Oser M, Yamaguchi H, Kim HD, Giampieri S, Wang Y, Goswami S, Wyckoff JB, Lauffenburger DA, Sahai E, Condeelis JS, Gertler FB. A Mena invasion isoform potentiates EGF-induced carcinoma cell invasion and metastasis. Dev Cell. 2008 Dec;15(6):813-28. doi: 10.1016/j.devcel.2008.09.003.
• Background Roussos ET, Condeelis JS, Patsialou A. Chemotaxis in cancer. Nat Rev Cancer. 2011 Jul 22;11(8):573-87. doi: 10.1038/nrc3078.
• Background Wang W, Wyckoff JB, Goswami S, Wang Y, Sidani M, Segall JE, Condeelis JS. Coordinated regulation of pathways for enhanced cell motility and chemotaxis is conserved in rat and mouse mammary tumors. Cancer Res. 2007 Apr 15;67(8):3505-11. doi: 10.1158/0008-5472.CAN-06-3714.
• Background Wang W, Goswami S, Lapidus K, Wells AL, Wyckoff JB, Sahai E, Singer RH, Segall JE, Condeelis JS. Identification and testing of a gene expression signature of invasive carcinoma cells within primary mammary tumors. Cancer Res. 2004 Dec 1;64(23):8585-94. doi: 10.1158/0008-5472.CAN-04-1136.
• Background Roussos ET, Keckesova Z, Haley JD, Epstein DM, Weinberg RA, Condeelis JS. AACR special conference on epithelial-mesenchymal transition and cancer progression and treatment. Cancer Res. 2010 Oct 1;70(19):7360-4. doi: 10.1158/0008-5472.CAN-10-1208. Epub 2010 Sep 7.
• Background Goswami S, Philippar U, Sun D, Patsialou A, Avraham J, Wang W, Di Modugno F, Nistico P, Gertler FB, Condeelis JS. Identification of invasion specific splice variants of the cytoskeletal protein Mena present in mammary tumor cells during invasion in vivo. Clin Exp Metastasis. 2009;26(2):153-9. doi: 10.1007/s10585-008-9225-8. Epub 2008 Nov 5.
• Background Breast International Group (BIG) 1-98 Collaborative Group; Thurlimann B, Keshaviah A, Coates AS, Mouridsen H, Mauriac L, Forbes JF, Paridaens R, Castiglione-Gertsch M, Gelber RD, Rabaglio M, Smith I, Wardley A, Price KN, Goldhirsch A. A comparison of letrozole and tamoxifen in postmenopausal women with early breast cancer. N Engl J Med. 2005 Dec 29;353(26):2747-57. doi: 10.1056/NEJMoa052258.
• Background Walsh BW, Schiff I, Rosner B, Greenberg L, Ravnikar V, Sacks FM. Effects of postmenopausal estrogen replacement on the concentrations and metabolism of plasma lipoproteins. N Engl J Med. 1991 Oct 24;325(17):1196-204. doi: 10.1056/NEJM199110243251702.
• Background Faltinova M, Vehmanen L, Lyytinen H, Haanpaa M, Hamalainen E, Tiitinen A, Blomqvist C, Mattson J. Effects of letrozole on serum estradiol and estrone in postmenopausal breast cancer patients and tolerability of treatment: a prospective trial using a highly sensitive LC-MS/MS (liquid chromatography-tandem mass spectrometry) method for estrogen measurement. Breast Cancer Res Treat. 2023 Oct;201(3):425-435. doi: 10.1007/s10549-023-07054-3. Epub 2023 Jul 25.
• Background Van Houdt M, Han SN, Pauwels S, Billen J, Neven P. Measurable Serum Estradiol and Estrone in Women 36-56 Years During Adjuvant Treatment With Aromatase Inhibitors for a Hormone Receptor-Positive Breast Cancer. Case Studies and Cross-sectional Study Using an Ultra-sensitive LC-MS/MS-Method. Clin Breast Cancer. 2023 Jan;23(1):84-90. doi: 10.1016/j.clbc.2022.09.007. Epub 2022 Sep 28.
• Background Dowsett M, Smith IE, Ebbs SR, Dixon JM, Skene A, Griffith C, Boeddinghaus I, Salter J, Detre S, Hills M, Ashley S, Francis S, Walsh G; IMPACT Trialists. Short-term changes in Ki-67 during neoadjuvant treatment of primary breast cancer with anastrozole or tamoxifen alone or combined correlate with recurrence-free survival. Clin Cancer Res. 2005 Jan 15;11(2 Pt 2):951s-8s.
• Background Ellis MJ, Coop A, Singh B, Tao Y, Llombart-Cussac A, Janicke F, Mauriac L, Quebe-Fehling E, Chaudri-Ross HA, Evans DB, Miller WR. Letrozole inhibits tumor proliferation more effectively than tamoxifen independent of HER1/2 expression status. Cancer Res. 2003 Oct 1;63(19):6523-31.
• Background Smith IE, Dowsett M, Ebbs SR, Dixon JM, Skene A, Blohmer JU, Ashley SE, Francis S, Boeddinghaus I, Walsh G; IMPACT Trialists Group. Neoadjuvant treatment of postmenopausal breast cancer with anastrozole, tamoxifen, or both in combination: the Immediate Preoperative Anastrozole, Tamoxifen, or Combined with Tamoxifen (IMPACT) multicenter double-blind randomized trial. J Clin Oncol. 2005 Aug 1;23(22):5108-16. doi: 10.1200/JCO.2005.04.005. Epub 2005 Jul 5.
• Background Smith I, Robertson J, Kilburn L, Wilcox M, Evans A, Holcombe C, Horgan K, Kirwan C, Mallon E, Sibbering M, Skene A, Vidya R, Cheang M, Banerji J, Morden J, Sidhu K, Dodson A, Bliss JM, Dowsett M. Long-term outcome and prognostic value of Ki67 after perioperative endocrine therapy in postmenopausal women with hormone-sensitive early breast cancer (POETIC): an open-label, multicentre, parallel-group, randomised, phase 3 trial. Lancet Oncol. 2020 Nov;21(11):1443-1454. doi: 10.1016/S1470-2045(20)30458-7.
• Background Lashen AG, Toss MS, Ghannam SF, Makhlouf S, Green A, Mongan NP, Rakha E. Expression, assessment and significance of Ki67 expression in breast cancer: an update. J Clin Pathol. 2023 Jun;76(6):357-364. doi: 10.1136/jcp-2022-208731. Epub 2023 Feb 22.
• Background Davey MG, Hynes SO, Kerin MJ, Miller N, Lowery AJ. Ki-67 as a Prognostic Biomarker in Invasive Breast Cancer. Cancers (Basel). 2021 Sep 3;13(17):4455. doi: 10.3390/cancers13174455.
• Background Sasano H, Sato S, Ito K, Yajima A, Nakamura J, Yoshihama M, Ariga K, Anderson TJ, Miller WR. Effects of aromatase inhibitors on the pathobiology of the human breast, endometrial and ovarian carcinoma. Endocr Relat Cancer. 1999 Jun;6(2):197-204. doi: 10.1677/erc.0.0060197.
• Background DeCensi A, Puntoni M, Guerrieri-Gonzaga A, Caviglia S, Avino F, Cortesi L, Taverniti C, Pacquola MG, Falcini F, Gulisano M, Digennaro M, Cariello A, Cagossi K, Pinotti G, Lazzeroni M, Serrano D, Branchi D, Campora S, Petrera M, Buttiron Webber T, Boni L, Bonanni B. Randomized Placebo Controlled Trial of Low-Dose Tamoxifen to Prevent Local and Contralateral Recurrence in Breast Intraepithelial Neoplasia. J Clin Oncol. 2019 Jul 1;37(19):1629-1637. doi: 10.1200/JCO.18.01779. Epub 2019 Apr 11.
• Background Meattini I, Tecic Vuger A, Becherini C, Epstein EJ, Garcia JP, Berger ER, Harbeck N. Multimodal De-Escalation Strategies in Early Breast Cancer. Am Soc Clin Oncol Educ Book. 2025 Jun;45(3):e473462. doi: 10.1200/EDBK-25-473462. Epub 2025 Jun 24.
• Background Lopez AM, Pruthi S, Boughey JC, Perloff M, Hsu CH, Lang JE, Ley M, Frank D, Taverna JA, Chow HH. Double-Blind, Randomized Trial of Alternative Letrozole Dosing Regimens in Postmenopausal Women with Increased Breast Cancer Risk. Cancer Prev Res (Phila). 2016 Feb;9(2):142-8. doi: 10.1158/1940-6207.CAPR-15-0322. Epub 2015 Dec 14.
• Background Pistilli B, Paci A, Ferreira AR, Di Meglio A, Poinsignon V, Bardet A, Menvielle G, Dumas A, Pinto S, Dauchy S, Fasse L, Cottu PH, Lerebours F, Coutant C, Lesur A, Tredan O, Soulie P, Vanlemmens L, Jouannaud C, Levy C, Everhard S, Arveux P, Martin AL, Dima A, Lin NU, Partridge AH, Delaloge S, Michiels S, Andre F, Vaz-Luis I. Serum Detection of Nonadherence to Adjuvant Tamoxifen and Breast Cancer Recurrence Risk. J Clin Oncol. 2020 Aug 20;38(24):2762-2772. doi: 10.1200/JCO.19.01758. Epub 2020 Jun 22.
• Background Huiart L, Ferdynus C, Giorgi R. A meta-regression analysis of the available data on adherence to adjuvant hormonal therapy in breast cancer: summarizing the data for clinicians. Breast Cancer Res Treat. 2013 Feb;138(1):325-8. doi: 10.1007/s10549-013-2422-4. Epub 2013 Feb 12. No abstract available.
• Background Briot K, Tubiana-Hulin M, Bastit L, Kloos I, Roux C. Effect of a switch of aromatase inhibitors on musculoskeletal symptoms in postmenopausal women with hormone-receptor-positive breast cancer: the ATOLL (articular tolerance of letrozole) study. Breast Cancer Res Treat. 2010 Feb;120(1):127-34. doi: 10.1007/s10549-009-0692-7. Epub 2009 Dec 25.
• Background Henry NL, Azzouz F, Desta Z, Li L, Nguyen AT, Lemler S, Hayden J, Tarpinian K, Yakim E, Flockhart DA, Stearns V, Hayes DF, Storniolo AM. Predictors of aromatase inhibitor discontinuation as a result of treatment-emergent symptoms in early-stage breast cancer. J Clin Oncol. 2012 Mar 20;30(9):936-42. doi: 10.1200/JCO.2011.38.0261. Epub 2012 Feb 13.
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• Background Bajetta E, Zilembo N, Bichisao E, Martinetti A, Buzzoni R, Pozzi P, Bidoli P, Ferrari L, Celio L. Tumor response and estrogen suppression in breast cancer patients treated with aromatase inhibitors. Ann Oncol. 2000 Aug;11(8):1017-22. doi: 10.1023/a:1008388823113.
• Background Plourde PV, Dyroff M, Dowsett M, Demers L, Yates R, Webster A. ARIMIDEX: a new oral, once-a-day aromatase inhibitor. J Steroid Biochem Mol Biol. 1995 Jun;53(1-6):175-9. doi: 10.1016/0960-0760(95)00045-2.
• Background Early Breast Cancer Trialists' Collaborative Group (EBCTCG). Aromatase inhibitors versus tamoxifen in early breast cancer: patient-level meta-analysis of the randomised trials. Lancet. 2015 Oct 3;386(10001):1341-1352. doi: 10.1016/S0140-6736(15)61074-1. Epub 2015 Jul 23.
• Background Johnston SR, Dowsett M. Aromatase inhibitors for breast cancer: lessons from the laboratory. Nat Rev Cancer. 2003 Nov;3(11):821-31. doi: 10.1038/nrc1211. No abstract available.
• Background Early Breast Cancer Trialists' Collaborative Group (EBCTCG). Effects of chemotherapy and hormonal therapy for early breast cancer on recurrence and 15-year survival: an overview of the randomised trials. Lancet. 2005 May 14-20;365(9472):1687-717. doi: 10.1016/S0140-6736(05)66544-0.
• Background Anampa J, Sparano JA. New agents for the management of resistant metastatic breast cancer. Expert Opin Pharmacother. 2017 Dec;18(17):1815-1831. doi: 10.1080/14656566.2017.1409206. Epub 2017 Nov 27.
• Background Burstein HJ, Lacchetti C, Anderson H, Buchholz TA, Davidson NE, Gelmon KA, Giordano SH, Hudis CA, Solky AJ, Stearns V, Winer EP, Griggs JJ. Adjuvant Endocrine Therapy for Women With Hormone Receptor-Positive Breast Cancer: ASCO Clinical Practice Guideline Focused Update. J Clin Oncol. 2019 Feb 10;37(5):423-438. doi: 10.1200/JCO.18.01160. Epub 2018 Nov 19.
• Background Miziak P, Baran M, Blaszczak E, Przybyszewska-Podstawka A, Kalafut J, Smok-Kalwat J, Dmoszynska-Graniczka M, Kielbus M, Stepulak A. Estrogen Receptor Signaling in Breast Cancer. Cancers (Basel). 2023 Sep 23;15(19):4689. doi: 10.3390/cancers15194689.
• Background Giaquinto AN, Sung H, Miller KD, Kramer JL, Newman LA, Minihan A, Jemal A, Siegel RL. Breast Cancer Statistics, 2022. CA Cancer J Clin. 2022 Nov;72(6):524-541. doi: 10.3322/caac.21754. Epub 2022 Oct 3.
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