Aggressive Disease Treatment Patterns and CtDNA HRR evaluatiON in High-volume metastatiC hORmone-sensitive Prostate Cancer in Russian FeDeration

This is a multicentre observational study on treatment approaches, demographic and clinical characteristics and on HRRm evaluation in ctDNA in patients with high-aggressive high-volume mHSPC with known tumor HRRm status in Russian Federation. The study will sequentially include only those patients who have signed the informed consent form (ICF). No procedures will be applied to patients in addition to the routine clinical practice.

Study population will consist of patients with high-aggressive (Gleason 8-10) high-volume mHSPC with available medical history and known tumor HRRm status, which has been determined from a tumour sample obtained from the patient as part of routine practice. It is estimated that approximately 400 patients will be enrolled in about 30 sites. In this case, the ratio of patients with HRR gene mutations (HRRm) to patients with wild-type HRR genes (HRRwt) will be approximately 5:3 (250 HRRm and 150 HRRwt), so that both populations are represented in the study sample, including patients without mutations.

The study will include two visits carried out according to routine clinical practice. At baseline visit (visit 1) demographic and clinical characteristics and treatment approaches from the date of high-aggressive high-volume mPC diagnosis (date of first metastases verification) till enrollment will be collected based on the patient's medical records. In case of absence of data required to be collected by the protocol, additional data may be obtained during patient's interview directly and recorded in the source documents related to the visit. For ctDNA and ctDNA-based HRRm testing (by NGS) routinely collected blood samples will be used. Testing will be performed in central laboratories.

Visit 2 (final visit) will be conducted at the time of disease progression or after 12 (±3) months (whichever occurs first) to collect follow-up data on progression to mCRPC and subsequent treatment, if applicable. If the patient is unable to visit the study site (e.g. in case the patient is being treated and observed at the place of residence) the data collection of visits 2 could be carried out via telephone contact.

All study data will be entered into electronic case report form (eCRF). The study physician will be responsible for ensuring that all required data is collected and entered into the eCRF.

Overall expected duration of the study (from the first patient inclusion to the final database lock) is about 38 months, or until 400 eligible patients are included to the study and data on these patients are collected (including follow-up data), whichever occurs first.

• Age at the diagnosis of high-aggressive high-volume mPC [Time frame: 36 months]
• Proportion of patients of different races and ethnicities [Time frame: 36 months]
• Proportion of patients with presence of a family oncology history [Time frame: 36 months]
• Proportion of patients with a personal oncology history [Time frame: 36 months]
• Proportion of patients with each category by ECOG assessmen [Time frame: 36 months]
• Proportion of patients with each type of mPC diagnosi [Time frame: 36 months]
• Proportion of patients with each stage by TNM classification [Time frame: 36 months]
• Proportion of patients with each histological type of tumor [Time frame: 36 months]
• Proportion of patients with each category by Gleason scale [Time frame: 36 months]
• Time from initial diagnosis to mPC diagnosis [Time frame: 36 months]
• Proportion of patients with each localization of metastases at the diagnosis of mPC [Time frame: 36 months]
• PSA level at the diagnosis of mPC [Time frame: 36 months]