Digital Biomarkers in Oncology: How Wearables and Patient-Generated Data Are Transforming Cancer Care

 

Digital Biomarkers in Oncology: How Wearables Are Transforming Cancer Care

Introduction

Cancer care is increasingly moving beyond traditional clinical measurements toward continuous, data-driven approaches that can provide a more detailed picture of how patients respond to disease and treatment.

One of the emerging technologies contributing to this transformation is the use of digital biomarkers.

Digital biomarkers are measurable, quantifiable physiological, behavioral, or functional characteristics that can be collected through digital technologies such as smartwatches, fitness trackers, wearable sensors, smartphones, connected medical devices, and remote monitoring platforms.

In oncology, these technologies are being investigated for their potential to capture information about physical activity, sleep, heart rate, mobility, physiological changes, treatment tolerance, symptoms, and other aspects of a patient's daily life.

The concept is particularly important because traditional clinical assessments often provide information only at specific time points. A patient may visit a clinic every few weeks, while a wearable device can potentially collect measurements continuously between visits.

The National Cancer Institute describes digital health as including wearable devices, mobile health, telehealth, personalized medicine, and the infrastructure required to integrate and analyze data from these technologies. NCI also identifies digital health as an area that can support cancer research, monitoring, patient engagement, and cancer-related care.

Recent research is expanding the investigation of wearable-derived measurements in oncology. A 2026 review specifically examined digital biomarkers derived from wearables in relation to systemic therapy toxicity and survival, while emphasizing that their usefulness can vary according to cancer type and treatment context.

This article explores how digital biomarkers and wearable technologies are being studied in oncology, their potential applications, current limitations, and their possible role in the future of personalized cancer care.

 

What Are Digital Biomarkers?

A digital biomarker is a measurable characteristic collected through digital technology that can provide information about a person's biological, physiological, behavioral, or functional state.

Unlike conventional laboratory biomarkers, which may involve blood tests, tissue samples, or imaging, digital biomarkers can often be collected remotely and repeatedly.

Examples of digital measurements include:

• Daily step counts
• Physical activity levels
• Heart rate
• Heart-rate variability
• Sleep duration
• Sleep efficiency
• Mobility patterns
• Respiratory measurements
• Body temperature
• Movement patterns
• Activity changes
• Functional performance
• Patient-reported symptoms collected through mobile applications

Wearable devices can collect many of these measurements continuously or at frequent intervals.

The important distinction is that a digital measurement is not automatically a validated clinical biomarker. Researchers must establish whether a particular digital signal is reproducible, clinically meaningful, and capable of improving patient assessment or decision-making.

This distinction is particularly important as digital technologies become more common in oncology research.

 

Why Digital Biomarkers Matter in Oncology

Cancer treatment can affect patients in ways that may not always be captured during a short clinical appointment.

For example, treatment may influence:

• Physical activity
• Fatigue
• Sleep
• Mobility
• Heart rate
• Daily functioning
• Exercise tolerance
• Recovery
• Overall quality of life

A wearable device may provide a continuous stream of information about some of these changes.

Instead of receiving only occasional measurements, researchers may be able to observe patterns over days or weeks.

This creates the possibility of moving from snapshot-based monitoring toward longitudinal monitoring.

However, continuous data should complement rather than automatically replace established clinical assessments. Current evidence remains heterogeneous, and wearable-derived measures require appropriate validation before they can be incorporated into routine oncology decision-making.

 

Wearable Technology in Cancer Care

Wearable technologies include a broad range of devices.

These can include:

Smartwatches

Smartwatches can collect measurements such as:

• Heart rate
• Physical activity
• Step counts
• Sleep patterns
• Movement
• In some devices, additional physiological measurements

Fitness Trackers

Fitness trackers can provide information about:

• Daily activity
• Exercise
• Walking
• Sedentary behavior
• Sleep

Wearable Sensors

Specialized sensors may be designed to measure specific physiological or functional characteristics.

Adhesive Patches

Wearable patches can continuously monitor selected physiological signals and may be useful in research and clinical settings.

Smart Rings

Some smart rings can collect physiological measurements such as sleep-related and heart-rate-related information.

Connected Medical Devices

Medical-grade connected devices can potentially provide more specialized measurements for research or patient monitoring.

The field is expanding beyond consumer wearables toward specialized sensors capable of collecting increasingly diverse biological and physiological signals.

A 2026 Nature Reviews Drug Discovery review analyzed 1,021 interventional trials registered between 2001 and 2025 that incorporated wearable-derived data, demonstrating the expanding role of wearable technologies in clinical research and drug development.

 

Patient-Generated Health Data

Wearables are part of a broader ecosystem of patient-generated health data.

This refers to health-related information created, recorded, or collected by patients outside traditional healthcare environments.

Examples include:

• Activity data
• Sleep information
• Home blood pressure measurements
• Symptom reports
• Medication adherence information
• Patient-reported outcomes
• Physiological measurements
• Smartphone-based assessments

In oncology, patient-generated data could help researchers understand what happens between clinic visits.

For example, a patient undergoing systemic therapy may experience fatigue or reduced mobility several days before the next scheduled appointment.

Continuous digital monitoring could potentially identify such changes earlier and provide additional information for clinical assessment.

NCI-supported digital health research includes technologies intended to support patient self-management, communication, remote monitoring, and cancer-related care.

 

Monitoring Physical Activity

Physical activity is one of the most commonly studied digital measurements in oncology.

Wearables can quantify:

• Daily steps
• Active minutes
• Walking distance
• Sedentary time
• Activity intensity
• Changes in mobility

Physical activity can provide information about functional status and changes in a patient's daily behavior.

A systematic review of wearable devices in oncology identified physical activity and step counts among the most frequently collected measures. The review included 199 studies involving more than 18,000 patients and found applications spanning rehabilitation, treatment monitoring, and prognostication.

However, researchers must distinguish between measuring activity and proving that an activity measurement independently predicts a clinical outcome.

That distinction requires carefully designed studies and validation.

 

Sleep as a Digital Biomarker

Sleep is another area of growing interest.

Cancer and its treatment can affect:

• Sleep duration
• Sleep quality
• Circadian patterns
• Night-time activity
• Daytime fatigue

Wearable devices can potentially collect repeated sleep-related measurements.

Researchers may investigate whether changes in sleep patterns are associated with:

• Treatment-related symptoms
• Fatigue
• Recovery
• Functional status
• Quality of life

Sleep measurements could therefore become part of broader digital profiles of patients undergoing cancer treatment.

However, wearable estimates of sleep should be interpreted carefully because consumer devices do not necessarily provide the same measurements as clinical sleep studies.

 

Heart Rate and Heart-Rate Variability

Heart rate and heart-rate variability are among the physiological measurements that can be collected through wearable devices.

Heart-rate variability reflects variation in the time interval between heartbeats and has been investigated as a potential indicator of physiological and autonomic changes.

In oncology research, investigators are exploring whether changes in heart-rate-related measures can provide information about:

• Treatment tolerance
• Physiological stress
• Recovery
• Functional status
• Treatment response
• Prognosis

A 2026 study of wearable-derived digital biomarkers in adults receiving systemic therapy found that the predictive value of wearable measures varied by clinical context. The researchers reported that standard clinical factors performed better than the wearable-only model for predicting severe treatment toxicity, while some wearable measures showed therapy-specific prognostic associations.

This illustrates an important principle:

Digital biomarkers are potentially useful complements to clinical information, not automatic replacements for established clinical assessments.

 

Digital Biomarkers for Treatment Monitoring

Cancer treatment can produce substantial changes in patients' physical and physiological status.

Digital monitoring may help researchers examine these changes between clinical visits.

Potential applications include monitoring:

• Physical activity
• Fatigue-related changes
• Sleep
• Mobility
• Physiological signals
• Functional recovery
• Patient-reported symptoms

For example, a sustained decline in activity could potentially signal worsening functional status.

However, the cause of such a change must be determined clinically. Reduced activity may result from treatment toxicity, infection, pain, emotional distress, hospitalization, or many other factors.

Therefore, digital biomarkers should be interpreted within the broader clinical context.

---

Digital Biomarkers and Treatment Toxicity

Treatment-related toxicity is an important challenge in oncology.

Chemotherapy, immunotherapy, targeted therapy, radiation therapy, and other treatments can produce adverse effects that vary between patients.

Researchers are investigating whether wearable-derived measurements could contribute to earlier recognition of changes associated with treatment tolerance.

Potential measurements include:

• Activity reduction
• Heart-rate changes
• Sleep disruption
• Mobility changes
• Functional decline

The goal is not simply to collect more data.

The important question is whether these measurements can provide clinically actionable information.

Current evidence indicates that wearable measures may provide additional insights in specific contexts, but their performance does not necessarily exceed established clinical variables across all patients and treatments.

 

Digital Biomarkers and Immunotherapy

Immunotherapy has transformed treatment for several cancers, but response and toxicity vary substantially among patients.

Researchers are exploring whether continuous physiological and behavioral measurements could provide additional information during immunotherapy.

Potential areas of investigation include:

• Changes in physical activity
• Sleep patterns
• Heart-rate-related measurements
• Functional status
• Symptoms
• Patient-reported outcomes

Combining these measurements with established biomarkers, imaging, laboratory tests, and molecular information could potentially create a more comprehensive picture of treatment response.

At present, this remains an emerging research area rather than an established replacement for conventional immunotherapy monitoring.

 

Remote Patient Monitoring in Oncology

Remote patient monitoring can help healthcare teams collect information from patients outside the hospital or clinic.

This can be particularly relevant for:

• Patients receiving outpatient treatment
• Cancer survivors
• Patients undergoing rehabilitation
• Individuals with mobility limitations
• Patients requiring frequent symptom monitoring

Remote monitoring can potentially reduce dependence on isolated clinic measurements.

It can also support communication between patients and healthcare professionals.

NCI research programs have highlighted remote symptom monitoring, telehealth, mobile applications, and digital technologies as areas of cancer-care research.

 

Digital Biomarkers in Cancer Rehabilitation

Cancer rehabilitation focuses on helping patients maintain or recover physical, functional, and psychosocial well-being.

Wearables can potentially support rehabilitation by measuring:

• Daily activity
• Walking
• Exercise
• Mobility
• Sedentary behavior
• Progress over time

For example, a rehabilitation program could use activity data to evaluate whether a patient is gradually increasing physical activity.

A systematic review found that wearable technologies have been widely investigated in oncology rehabilitation, although evidence for direct improvements in major clinical outcomes remains limited.

This means wearables may provide useful monitoring capabilities, but clinical benefit must still be established through appropriate research.

 

AI and Digital Biomarkers

The amount of information generated by wearable devices can be substantial.

Artificial intelligence and machine-learning techniques may help researchers identify patterns within large datasets.

AI could potentially be used for:

• Pattern recognition
• Risk modeling
• Signal processing
• Anomaly detection
• Patient stratification
• Longitudinal trend analysis
• Prediction modeling

For example, an algorithm could analyze activity, sleep, and heart-rate patterns together rather than considering each measurement independently.

However, AI performance depends heavily on the quality and representativeness of the underlying data.

Poor-quality measurements, missing data, inconsistent device use, and differences between devices can affect model performance.

 

Combining Digital Biomarkers With Multi-Omics

The future of precision oncology is increasingly based on integrating multiple sources of information.

Digital biomarkers could potentially be combined with:

• Genomics
• Transcriptomics
• Proteomics
• Metabolomics
• Imaging
• Liquid biopsy
• Pathology
• Clinical records
• Patient-reported outcomes

This could create a more comprehensive patient profile.

For example, molecular data may describe the biology of a tumor, while wearable data may provide information about the patient's physiological and functional state.

Together, these datasets could potentially provide complementary information.

The challenge is developing reliable systems capable of integrating such diverse data without introducing bias or unnecessary complexity.

 

Digital Biomarkers in Clinical Trials

Clinical trials traditionally depend on scheduled clinic visits and predefined assessments.

Wearables can potentially provide continuous real-world measurements.

A 2026 review in Nature Reviews Drug Discovery found that wearable technologies are increasingly incorporated into clinical trials and can provide physiological and behavioral endpoints outside conventional clinical settings. The review also emphasized that formal regulatory qualification of wearable-derived measures remains uncommon.

Potential advantages include:

• Continuous data collection
• Remote monitoring
• Reduced dependence on clinic visits
• Real-world measurements
• Greater temporal resolution
• Patient-centered data collection

However, clinical trials must address device adherence, missing data, interoperability, validation, privacy, and regulatory requirements.

 

Challenges in Using Wearables for Cancer Care

Despite their potential, digital biomarkers face several challenges.

1. Data Quality

Wearable measurements can be affected by:

• Device placement
• Motion artifacts
• Battery limitations
• Sensor quality
• Missing data
• Incorrect usage

2. Device Differences

Different devices may measure the same physiological variable differently.

This makes standardization important.

3. Patient Adherence

Patients may forget to wear a device, stop using it, or use it inconsistently.

4. Privacy and Security

Continuous health data can contain sensitive information.

Strong privacy and cybersecurity protections are therefore essential.

5. Clinical Validation

A correlation between a digital signal and a clinical outcome does not automatically establish clinical usefulness.

Researchers need robust validation studies.

6. Health Equity

Not every patient has equal access to smartphones, wearable devices, high-speed internet, or digital health infrastructure.

Technology-based oncology care therefore needs to consider accessibility and equity.

7. Regulatory Qualification

Digital measurements intended to support clinical decisions may require appropriate regulatory evaluation.

The current evidence base shows growing research activity, but clinically validated digital biomarkers remain limited.

 

From Wearable Data to Clinically Meaningful Biomarkers

One of the biggest challenges is moving from data collection to clinical interpretation.

A smartwatch may record thousands of data points every day.

But more data does not automatically mean better healthcare.

Researchers need to determine:

1. Which measurements are reliable?
2. Which measurements are biologically meaningful?
3. Which measurements are reproducible?
4. Which measurements correlate with important clinical outcomes?
5. Can the information change clinical management?
6. Does using the measurement improve patient outcomes?

These questions will determine whether digital measurements evolve into clinically meaningful biomarkers.

 

The Future of Digital Biomarkers in Oncology

Future digital biomarker systems may become more sophisticated as wearable sensors, AI, remote monitoring, and biomedical engineering continue to advance.

Emerging technologies may allow wearable devices to measure increasingly diverse physiological and biochemical signals.

For example, researchers are investigating wearable biochemical sensing approaches capable of monitoring molecules continuously or repeatedly. A 2026 Nature Biotechnology study reported a pilot clinical trial of a wearable electrochemical aptamer-based patch for continuous drug-concentration measurement, illustrating the direction of development toward biochemical rather than purely behavioral sensing.

Future platforms may therefore move from:

Activity tracking → physiological monitoring → biochemical sensing → integrated digital biomarkers

This evolution could eventually make wearable technologies more relevant to precision medicine.

However, clinical translation will depend on rigorous validation and demonstration of meaningful patient benefit.

 

Personalized Cancer Care

The ultimate objective of digital biomarkers is not simply to collect more information.

It is to improve understanding of individual patients.

Cancer patients differ in:

• Tumor biology
• Treatment response
• Physical condition
• Comorbidities
• Lifestyle
• Functional status
• Treatment tolerance
• Recovery patterns

Continuous digital measurements could potentially provide an additional layer of individualized information.

When combined with molecular biomarkers and clinical data, digital biomarkers may contribute to a more comprehensive model of personalized cancer care.

 

What Comes Next?

The next stage of digital biomarker research will likely focus on validation and integration.

Important research priorities include:

• Standardizing wearable measurements
• Establishing clinically meaningful endpoints
• Improving sensor accuracy
• Developing interoperable data systems
• Protecting patient privacy
• Improving accessibility
• Validating biomarkers across diverse populations
• Integrating wearable data with clinical records
• Combining digital biomarkers with molecular biomarkers
• Establishing regulatory pathways
• Demonstrating measurable improvements in patient outcomes

The field is therefore moving from the question “Can we collect this data?” toward the more important question “How can this data improve cancer care?”

 

Conclusion

Digital biomarkers are emerging as an important area of research at the intersection of oncology, wearable technology, digital health, and precision medicine.

Wearable devices can capture continuous or repeated information about physical activity, sleep, heart rate, mobility, and other physiological characteristics. These measurements may provide additional insights into treatment tolerance, functional status, rehabilitation, and patient experiences between traditional clinical visits.

Research has demonstrated substantial interest in wearable technologies among oncology patients, while recent studies also highlight an important limitation: wearable-derived measures do not automatically outperform conventional clinical assessments and require context-specific validation.

The future may involve combining digital biomarkers with genomics, liquid biopsy, imaging, pathology, AI, and other sources of clinical information.

If validated effectively, these technologies could contribute to a more continuous, personalized, and patient-centered approach to cancer care.

The broader vision is not to replace oncologists or established diagnostic methods, but to provide additional high-quality information that can help researchers and healthcare professionals better understand patients throughout the cancer journey.

 

FAQs

1. What are digital biomarkers in oncology?

Digital biomarkers are measurable physiological, behavioral, or functional characteristics collected through digital technologies such as wearable devices, smartphones, and connected sensors. In oncology, they are being studied for applications including treatment monitoring, rehabilitation, prognostication, and patient monitoring.

2. How can wearable devices help cancer patients?

Wearable devices can collect information such as physical activity, step counts, sleep patterns, heart rate, and other measurements. Researchers are studying whether these data can provide additional information about treatment tolerance, functional status, recovery, and patient well-being.

3. Can wearable devices detect cancer?

Wearable devices are not currently established as general-purpose cancer detection tools. Current oncology research primarily investigates their potential for monitoring physiological and behavioral changes, treatment effects, rehabilitation, and other aspects of cancer care.

4. Can digital biomarkers predict cancer treatment toxicity?

Some studies are investigating whether wearable-derived measurements can contribute to predicting treatment toxicity. However, recent evidence indicates that their predictive performance can vary by cancer type and treatment, and conventional clinical factors may still perform better for certain outcomes.

5. What types of data can wearables collect?

Depending on the device, wearables may collect data related to physical activity, steps, heart rate, heart-rate variability, sleep, movement, temperature, and other physiological characteristics.

6. How is AI used with digital biomarkers?

AI and machine-learning methods can analyze large volumes of wearable data, identify patterns, detect changes, and develop predictive models. These approaches require high-quality data and appropriate validation before being used for clinical decision-making.

7. Are digital biomarkers already used routinely in oncology?

Digital biomarkers are an active research area, but many applications have not yet achieved widespread routine clinical adoption. Researchers continue to evaluate their validity, reliability, clinical usefulness, and regulatory requirements.

8. What are the main challenges of digital biomarkers?

Major challenges include data quality, device differences, patient adherence, privacy, cybersecurity, interoperability, health equity, clinical validation, and regulatory qualification.

9. Can digital biomarkers be combined with molecular biomarkers?

Yes. Researchers are exploring ways to combine digital measurements with genomic, transcriptomic, proteomic, metabolomic, imaging, liquid biopsy, and clinical data to create more comprehensive patient profiles.

10. What is the future of digital biomarkers in cancer care?

Future research may focus on continuous physiological monitoring, biochemical sensing, AI-powered analysis, remote patient monitoring, clinical-trial applications, and integration with precision oncology platforms.

 

Oncology Summit-2027

The International Experts Summit on Oncology & Cancer Care (Oncology Summit-2027) will bring together oncologists, researchers, clinicians, healthcare professionals, and experts to discuss emerging developments in cancer research and care.

March 25–27, 2027 | Osaka, Japan

The summit will feature scientific presentations, keynote sessions, panel discussions, and opportunities for knowledge exchange across areas including precision medicine, cancer biomarkers, immuno-oncology, cancer genomics, early detection, AI and machine learning, novel therapeutics, clinical trials, survivorship, and patient-centered cancer care.