This study, called PERSEVERE, examines how local treatment for early breast cancer affects people's health and daily lives over time.

People who join the study will have early-stage breast cancer and receive treatment such as surgery and other therapies that are used before or after surgery. The study does not include people with late-stage (metastatic) breast cancer.

Researchers want to learn about short- and long-term side effects that can happen during or after treatment. These may include tiredness, trouble sleeping, emotional distress, pain, or changes in heart or lung function. The study also looks at how these effects impact participants' quality of life.

Participants will be asked to complete surveys about how they feel. They will also have health checks, such as heart tests, lung function tests, and blood samples. Tissue samples from surgery will also be collected.

The goal is to understand better how different people respond to breast cancer treatment and find ways to support long-term recovery.

PERSEVERE is a prospective, multi-modal cohort study designed to evaluate treatment-related toxicities and quality of life in people with stage I-III early breast cancer receiving local therapy in China. Participants will be eligible if they either:

Receive neoadjuvant therapy (such as chemotherapy or targeted therapy) prior to surgery, or

Undergo surgery followed by postoperative adjuvant therapy, including chemotherapy, radiotherapy, endocrine therapy, or targeted therapy.

The study does not include individuals with recurrent or metastatic breast cancer.

Study Objectives and Methods This study aims to understand the short- and long-term physical, psychological, and social effects of breast cancer treatment and how they impact participants' recovery and daily life.

At baseline, the study collects comprehensive information on participants':

Sociodemographic status: marital status, education level, and household income

Anthropometric measurements: height, weight, body mass index (BMI), waist and hip circumference

Medical history: personal medical history, comorbidities, and past treatments

Reproductive history: menstrual and fertility history

Participants also undergo baseline clinical assessments, including:

Echocardiography (e.g., LVEF) to screen for cardiotoxicity

Pulmonary function testing, conducted for participants aged 70 or older

Routine laboratory tests, such as liver and kidney function, lipid metabolism, and inflammation markers

Biospecimens collected at baseline include:

Peripheral blood (plasma and PBMCs)

Tumor and adjacent normal tissue from surgery

These samples are stored for future biomarker discovery, multi-omics analyses, and translational research on treatment-related toxicities.

Following baseline assessments, participants complete a series of validated patient-reported outcome (PRO) questionnaires, which provide insight into their physical symptoms, emotional well-being, and quality of life. These include:

EORTC QLQ-C30 and QLQ-BR23 for cancer-related quality of life

HADS (Hospital Anxiety and Depression Scale)

Pittsburgh Sleep Quality Index (PSQI) for sleep disturbances

Brief Pain Inventory - Short Form (BPI-SF)

Perceived Stress Scale (PSS-10) for psychological stress

Social Support Rating Scale (SSRS) for social support assessment

Follow-up and Data Collection

Participants are followed using standardized electronic questionnaires administered via the REDCap platform at:

Postoperative week 1, month 1, month 3, and every 6-12 months thereafter for up to 5 years

No repeat biospecimen or clinical tests are collected after baseline. Follow-up focuses on tracking changes in symptoms and quality of life through PROs, enabling analysis of individual recovery trajectories.

Quality Assurance Data collection uses REDCap with built-in logic and range validation

A structured data dictionary ensures consistency across sites

SOPs guide recruitment, consent, biospecimen handling, adverse event reporting, and data entry

Source data verification will be conducted on a sample of participants

Missing data will be managed using statistical imputation and sensitivity analysis

Study Innovation and Impact

PERSEVERE is one of the first large-scale prospective cohort studies in China specifically focused on treatment-related toxicities and quality of life in breast cancer patients. It is designed to:

Capture a comprehensive picture of treatment-related toxicities, beyond acute effects

Enable integrative analysis of biological, physical, and psychological indicators

Build a clinical-biological dataset for developing prediction tools and AI-driven recovery models

Guide personalized supportive care strategies based on Chinese breast cancer patients' needs

The findings will provide new insights into survivorship and recovery and help clinicians deliver evidence-based, patient-centered care.

Inclusion Criteria:

• Women aged 18 years or older
• Diagnosed with stage I, II, or III invasive breast cancer confirmed by pathology or cytology
• No signs of metastatic disease (cancer that has spread to other parts of the body)
• Scheduled to receive local treatment, including:

Surgery

And/or neoadjuvant or adjuvant therapy such as chemotherapy, radiation, hormone therapy, or targeted therapy

• Willing and able to complete health questionnaires and attend follow-up visits
• Has given written informed consent to join the study

Exclusion Criteria:

• Have metastatic breast cancer or local recurrence
• Have already received curative treatment (surgery, chemo, etc.) for the current breast cancer before joining the study
• Are currently pregnant or breastfeeding
• Have a history of another cancer within the past 5 years (except for non-melanoma skin cancer or in-situ cervical cancer)
• Are unable to participate in the study due to mental, physical, or legal reasons (for example, under legal guardianship or imprisonment)

Participants will be recruited from multiple hospitals across China. The study is coordinated by the Cancer Hospital, Chinese Academy of Medical Sciences (CAMS), and includes collaborating sites such as Shanxi Cancer Hospital and the CAMS Cancer Hospital Shenzhen branch. Additional centers from both northern and southern regions of China will be added as the study expands. The study population includes women diagnosed with stage I-III breast cancer who are receiving local therapy in real-world clinical settings across diverse geographic areas.

PERSEVERE will share de-identified individual data that underlie the results reported. A decision concerning the sharing of other study documents, including protocol and statistical analysis plan will be examined upon request.

We will consider access to study data upon written detailed request sent to us, from 6 months until 5 years after publication of summary data.

The data shared will be limit to that required for independent mandated verification of the published results, the applicant will need authorization from the study for personal access, and data will only be transferred after signing of a data access agreement.