This thesis focuses on treatment outcomes of high risk endometrial cancer and corresponding patients’ and clinicians’ preferences regarding adjuvant treatment decisions; molecular studies on the... Show moreThis thesis focuses on treatment outcomes of high risk endometrial cancer and corresponding patients’ and clinicians’ preferences regarding adjuvant treatment decisions; molecular studies on the etiology of mismatch repair deficiency (MMRd) in intermediate and high risk endometrial cancer; and the combination of immunotherapy and PARP inhibition for the treatment of recurrent or metastatic endometrial cancer.The overall aims of this thesis were:• To evaluate health-related quality of life up to 5 years after chemoradiotherapy compared with pelvic radiotherapy alone in the adjuvant treatment of high risk endometrial cancer in the PORTEC-3 trial;• To investigate the preferences of patients and clinicians regarding the benefit-risk trade-off of the addition of chemotherapy to adjuvant pelvic radiotherapy;• To investigate the prevalence and prognosis of Lynch syndrome-associated endometrial cancer among MMRd endometrial cancers;• To evaluate the role of combined checkpoint inhibition and PARP inhibition in women with metastatic or recurrent endometrial cancer in terms of progression-free survival and toxicity in the DOMEC trial. Show less
Chondrosarcoma and giant cell tumour of bone (GCTB) are bone tumours characterized by recurrent mutations (IDH1/IDH2 and H3F3A, respectively) that induce remodelling of the epigenetic landscape.... Show moreChondrosarcoma and giant cell tumour of bone (GCTB) are bone tumours characterized by recurrent mutations (IDH1/IDH2 and H3F3A, respectively) that induce remodelling of the epigenetic landscape. The standard of care for both of these sarcoma subtypes is surgery and alternative treatment options for patients with inoperable disease are currently lacking (chondrosarcoma) or suboptimal (GCTB). Therefore, the aim of this thesis was to identify novel therapeutic targets for high-grade chondrosarcoma as well as GCTB, with a focus on potential therapies that could counteract the remodelling of the epigenome. PARP and HDAC inhibition, alone or in combination treatment strategies, were identified as promising therapeutic strategies for chondrosarcoma or both of these bone tumours, respectively. Additionally, this thesis describes the development and use of novel 3D cell culture models which can be used to improve the translation of preclinical findings to the clinic. Show less
Geyer, C.E.; Garber, J.E.; Gelber, R.D.; Yothers, G.; Taboada, M.; Ross, L.; ... ; OlympiA Clinical Trial Steering Committee and Investigators 2022
Background: The randomized, double-blind OlympiA trial compared 1 year of the oral poly(adenosine diphosphate-ribose) polymerase inhibitor, olaparib, to matching placebo as adjuvant therapy for... Show moreBackground: The randomized, double-blind OlympiA trial compared 1 year of the oral poly(adenosine diphosphate-ribose) polymerase inhibitor, olaparib, to matching placebo as adjuvant therapy for patients with pathogenic or likely pathogenic variants in germline BRCA1 or BRCA2 (gBRCA1/2pv) and high-risk, human epidermal growth factor receptor 2-negative, early breast cancer (EBC). The first pre-specified interim analysis (IA) previously demonstrated statistically significant improvement in invasive disease-free survival (IDFS) and distant disease-free survival (DDFS). The olaparib group had fewer deaths than the placebo group, but the difference did not reach statistical significance for overall survival (OS). We now report the pre-specified second IA of OS with updates of IDFS, DDFS, and safety. Patients and methods: One thousand eight hundred and thirty-six patients were randomly assigned to olaparib or placebo following (neo)adjuvant chemotherapy, surgery, and radiation therapy if indicated. Endocrine therapy was given concurrently with study medication for hormone receptor-positive cancers. Statistical significance for OS at this IA required P < 0.015. Results: With a median follow-up of 3.5 years, the second IA of OS demonstrated significant improvement in the olaparib group relative to the placebo group [hazard ratio 0.68; 98.5% confidence interval (CI) 0.47-0.97; P = 0.009]. Four-year OS was 89.8% in the olaparib group and 86.4% in the placebo group (Delta 3.4%, 95% CI -0.1% to 6.8%). Four-year IDFS for the olaparib group versus placebo group was 82.7% versus 75.4% (Delta 7.3%, 95% CI 3.0% to 11.5%) and 4-year DDFS was 86.5% versus 79.1% (Delta 7.4%, 95% CI 3.6% to 11.3%), respectively. Subset analyses for OS, IDFS, and DDFS demonstrated benefit across major subgroups. No new safety signals were identified including no new cases of acute myeloid leukemia or myelodysplastic syndrome. Conclusion: With 35 years of median follow-up, OlympiA demonstrates statistically significant improvement in OS with adjuvant olaparib compared with placebo for gBRCA1/2pv-associated EBC and maintained improvements in the previously reported, statistically significant endpoints of IDES and DDFS with no new safety signals. Show less
Inactivating mutations in BRCA1 or BRCA2 genes predispose to several types of cancer. Owing to their roles in maintaining genomic stability, lack of BRCA1/2 results in DNA damage repair defects, a... Show moreInactivating mutations in BRCA1 or BRCA2 genes predispose to several types of cancer. Owing to their roles in maintaining genomic stability, lack of BRCA1/2 results in DNA damage repair defects, a vulnerability that can be exploited therapeutically by the inhibition of poly(ADPribose) polymerase 1 (PARP1). Unfortunately, clinical benefit of PARPi therapy is often limited by emerging drug resistance. Identification of PARPi resistance mechanisms is therefore crucial to improve the clinical outcome and design strategies that would ultimately prevent or target resistant tumors.The use of genetically engineered mouse models (GEMMs) of BRCA1/2-associated breastcancer in this work has allowed us to model PARPi resistance in vivo in well-defined genetic contexts. By combining high-throughput genetic screens, multiple omics analyses and functional assays, we identified several factors of PARPi resistance and explained their role in therapy failure. Moreover, we established a new tumor-derived organoid system thatenables robust in vivo validation of putative drug resistance factors. Finally, work described in this thesis has advanced our understanding of basic biological processes involved in DNA damage signaling and repair. Show less