Background: Little is known about how to best predict postoperative outcomes and chemotherapy tolerance in an increasingly aging and complex gynecologic oncology (GO) population. Frailty is a multidimensional age-related and disease-related state of vulnerability to stressors due to reduced capacity of different physiological systems. Resource limitations are a barrier to routine adoption of frailty assessments through comprehensive clinical evaluations in daily practice. This highlights the relevance of studying potential biomarkers of frailty, which could complement or replace clinical assessments. Frailty has been associated with worse perioperative and oncologic outcomes in many subspecialties, however the literature in patients with gynecologic malignancies is very limited. Methods: The FARGO study is a multi-centre prospective cohort study of 280 patients aged ≥55 years-old undergoing surgery, with or without chemotherapy for a suspected or confirmed gynecologic malignancy. Patient recruitment will occur over 13 months. The over-arching goal is to evaluate the predictive value of frailty assessments in predicting surgical and chemotherapy outcomes. The two primary objectives are: 1) To evaluate the predictive value of preoperative frailty assessment based on the Frailty Phenotype (FP), compared to a perioperative cardiovascular risk assessment, in predicting the composite of all-cause death or new disability at 6 months after surgery 2) To create of a biobank to explore possible biomarkers of frailty, including mitochondrial DNA levels. Secondary objectives include to evaluate the predictive value of clinical and biomarker frailty assessment for 30-day postoperative complications, for chemotherapy tolerance and 1-year recurrence-free survival. Patients will undergo frailty and cardiovascular risk assessment prior to surgery and/or neoadjuvant chemotherapy. A trained clinical research assistant will measure frailty based on the clinical frailty scale (CFS) and the FP. The cardiovascular risk calculation will be based on the preoperative Revised Cardiac Risk Index, age, and occurrence of myocardial injury after non-cardiac surgery (MINS). Research personnel blinded to the frailty and cardiovascular risk assessment will evaluate study outcomes including death, disability, and clinical events at 30 days, 6 months, and 12 months after surgery. Disability will be measured with the WHODAS 2.0 (World Health Organization Disability Assessment Schedule), a validated patient-reported outcome measure. Pre-specified blood biomarkers will be measured. Our study emphasizes patient-centered outcomes (i.e. loss of independence, short and long-term disability) and system-level outcomes. Our findings may have important implications to assist in risk stratification and planning for oncologic treatments and perioperative care needs.Clinical trial information: will be added later.