Wearable medical devices, whether they be smart watches or wearable at-home infusion devices or pumps, are playing a more prominent role in cancer care.
Wearable health monitoring technology such as smart watches and fitness trackers have exploded in recent years. Additionally, wearable devices that dispense anti-cancer therapy have also grown in popularity. These devices have the potential to be practice changing as they grow in popularity, sophistication, and usefulness.
Wearable deceives can largely be split into 1 of 2 categories. In the first category, you have wearable, often consumer-marker, fitness trackers. This can include smart watches that track steps, pulse, and other biologic metrics or other devices. In the second category, you have wearable medication delivery systems. This type of device is most often associated with diabetes insulin pumps, however, are becoming more common in other fields, such as oncology.
“The general idea that through a non-invasive device, we're able to continuously monitor a patient's health, if there are any aberrations, if they opt into that, I think is increasingly going to be one of the areas in health we're going to have continued innovation and progress in, because our treatments need to get better. But if we can enact those treatments, and intercept disease before, things get too out of hand, I think it'll be even more impactful. I think that's where wearables can really help us,” said Sandip P. Patel, MD, a medical oncologist at the University of California San Diego Health in an interview with Targeted Therapies in Oncology (TTO).
A study published in Nature found that 80% of American adults own a smartphone. Smartphones contain sensors such as a three-axis accelerometer, gyroscope, magnetometer, and other useful sensors that can provide care providers real-time information on mobility, device use, environment, and social interactions. Smart watches take it one step further by providing data on sleep, social interaction, and physical activity. Researchers believe that by tracking these important metrics, physician can identify adverse events (AEs) sooner, leading to a better quality of life and potentially prolonging survival.1
“For adults affected by cancer, mobile sensing can capture fluctuations in behavior that may reflect meaningful variation in functional status, symptom burden, quality of life, and risk for readmission and other adverse outcomes. Continuous assessment of these digital biomarkerscould enable real-time monitoring of patients between clinical encounters, extending the coverage and reach of care. Further, sharing actionable insights from data analyses with providers, patients, and caregivers could lead to more proactive and personalized care,” wrote study authors.
However, these wearable devices are only owned by 21% of the American adult population. This number is even smaller for older adults and those who live in rural areas. While smartphones are owned by over 80% of adults in the United States, they do not collect the same data that smart watches do.
Another drawback of such devices is, paradoxically, the sheer amount of data they produce. High-end smart devices such as fitness trackers are constantly collecting data, and interpreting, sorting, and utilizing the sheer volume of information produced by those devices leads to challenges.
A study around wearable technologies published in the American Society of Clinical Oncology Educational Book found that of a study of approximately 300 patients who wore a smart watch every day for a 3 months created 6 million kilobytes of data, a number that may actually exceed the capacity of many medical instruction’s computer system.2
Cloud-based storage could provide a solution to this problem. However, this solution comes with its own issues such as privacy, security, and uploading issues. In order for success, interoperability and a team to alert care providers to any aberrant values in the data at the time of upload are necessary. Additionally, transfer of data could take hours or days if it is not house locally, which could lead to limited clinical benefit.
“Collected data may require substantial cleanup prior to interpretation. For example, additional activity data may be collected and stored in duplicate if individuals use exercise apps that also collect physical activity data (e.g., Strava, Runkeeper). In addition, the time zone for the activity monitor may not match the location (Apple Watch reports all data at Greenwich time). Gaps exist in the data because activity is not continuously recorded,” study authors write. “This makes it difficult to determine if an individual is inactive versus not wearing the device because individuals must wear the device a minimum number of hours per day to get reliable data for that day (in our study, we chose a minimum of 7 hours/day, and if any data were recorded by the watch during an hour, individuals were credited with wearing the device for the entire hour). Furthermore, one needs to determine how to analyze the data. Continuous measures may need to be converted to summary measures, such as average values per day.”
A 2019 study found that in survey of 106 respondents, half did not understand why their health information should be protected. The survey also found a lack of awareness over potential privacy and security issues surrounding such devices. This points to a lack of knowledge around the risks associated with wearable devices, meaning an education campaign will be necessary.3
“The key is just how do you abstract that data in a meaningful format that has a really good signal to noise ratio, so that a patient knows when to call or better yet, systems are automated, to call for help, but do so in a meaningful and accurate way that doesn't overwhelm both the patient the health system with false positives. I think that's the key with any technological implementation, where the technology ends, and the human begins,” said Patel. “That's often where these things can fall apart. And I think this is one area as the technology improves, and we start to be able to monitor multiple organ systems simultaneously, how do we make that meaningful for that human-to-human interaction that is fundamental to take care of that patient?”
However, despite their many limitations, wearable devices seem to be here to stay. According to experts, clinicians should be early adaptors of such technology, figuring out how to adapt them into practice as much as possible. However, an effort also needs to be made to “mix early adoption with a conservative bent to separate hype from true benefit.”2
The second grouping of wearable devices in the fight against cancer is wearable medical delivery systems. These deceives are not nearly as widespread as wearable fitness trackers, and many are still in the development stage. For the most part, such devices tend to live in the diabetes space, most notably with insulin pumps.
However, recent advances may pivot such devices to the oncology space as well, not only in drug delivery but also in cancer detection.
One such device showing early promise is a wearable biomarker device from University of Michigan has the potential to replace biopsy in certain carcinomas, according to a 2019 article, “A temporary indwelling intravascular aphaeretic system for in vivo enrichment of circulating tumor cells.”4
According to the article, circulating tumor cells (TCT) are an established biomarker for the prognosis of patients with various cancer types. However, isolating these cells relies on a small amount of blood from a single venipuncture, thereby limiting the number of CTC’s captured. This can often lead to inaccurate variability and reflection of tumor cell heterogeneity.
The proposed device would shrink the existing machine down to a wearable size. Over the course of 2 hours, it could screen 1%-2% of all the blood in the body, a much larger amount than traditional methods. The device is designed to send updated results wirelessly to a phone or other device.
In a canine model, the first cells were detected less than a minute after injection, with cell count maximum being achieved at 30 minutes. However, cells were detected throughout the entire 2-hour procedure. Additionally, no short- or long-term AEs were observed from the injection and venipunction.
“We have validated our approach in a canine model by successfully interrogating 1–2% of the entire canine blood volume over 2 h to isolate cancer cells in vivo. Major concerns regarding sterility, intra-device clotting, as well as intravascular thrombosis have been resolved by several strategies, including rigorous sterilization procedures and incorporation of a continuous heparin infusion injector,” study authors wrote. “Furthermore, device clogging anticipated by saturating the CTC capture module with CTCs has been solved by the design of interchangeable CTC chips. This feature suggests that the system could be left in place for longer periods of time, potentially permitting even higher blood volume interrogation at little or no harm and minimal patient inconvenience. Further, previous in vivo CTC isolation strategies using standard cataphoresis necessitate bedside peripheral blood collection and are encumbered with potential blood cell loss. Our system is wearable, thereby allowing full patient mobility during operation with minimal cell loss.”
Additionally, there are some wearable devices delivering cancer drugs to patients. For example, the TriNav Infusion System, which uses a propriety pressure-enabled drug delivery (PEDD) system that is meant to help patients with hepatocellular carcinoma who are either transplant ineligible become transplant eligible or help those who are transplant eligible through the waiting period through the admittance of locoregional therapy.5
The device, which was developed by TriSalus Life Sciences, 2020, can be used with either a 0.035-inch and 0.038-inch catheters. The device uses the body’s natural blood flow to increase infusion pressure while also overcoming interstitial fluid pressure and solid stress.5
The device has been validated in several studies, according to its developer. For example, compared to EH microcatheters, which have an objective response rate of 76.5%, the PEDD system has a 100% objective response rate. Additionally, the rate of tumor necrosis after 1 treatment was 88.8% for the PEDD system compared to the 33.8% for EH microcatheters. After all treatments were completed, the PEDD system had a tumor necrosis rate of 89% while the eh microcatheters had a tumor necrosis of 56.1%. Nine in ten patients were also successfully down staged after their first treatment.
Memorial Sloan Kettering Cancer Center offers a similar device, an elastomeric pump that administered chemotherapy at a steady rate into the blood stream. After the pump is connected, the patient is able to go home. The entire infusion takes about 48 hours. The pump is worn between the hips and armpits. Most normal activities such as light exercise and sexual activity, can be continued while wearing the device.6
Wearable medication delivery devices still have a long way to go before they are widespread. More research is needed into their efficacy and usability. Additionally, such devices do not come without risks. Like any other device, they may not work properly or malfunction. The patient may need additional training on how to use the device or what to do if it doesn’t perform the way it should. However, as they become more common, they have the potential to be practice changing as they may increase precision and medication adherence, potentially avoiding the risk of complications down the line.
Wearable medical devices, whether they be smart watches or wearable at-home infusion devices or pumps, are playing a more prominent role in cancer care. Care centers should make an effort to integrate these devices into their own practice where appropriate but should ensure that what they are doing is backed by evidence and is safe and effective.
These devices carry both risks and benefits, which both patients and clinicians should be made aware of. These devices can be helpful, with the potential to improve symptom management and prolong life. However, they carry the risk of malfunction, data storage issues, and other complications.
“I think wearables will be a tool that are probably going to be omnipresent, similar to using a phone to monitor vaccine toxicities, like we already do for COVID-19, one can envision wearables automating that for a lot of aspects of our care. And I think, for cancer patients in particular, may be impactful because cancer patients just have so much going on, that having something automated, like an R2D2 basically, in their phone as a wearable, that kind of helps us help them. I think it's just going to be really impactful,” said Patel.
1. Low, C.A. Harnessing consumer smartphone and wearable sensors for clinical cancer research. npj Digit. Med. 2020;3 (140). doi: 10.1038/s41746-020-00351-x
2. Liao Y, Thompson C, Peterson S, et al. The Future of Wearable Technologies and Remote Monitoring in Health Care. Am Soc Clin Oncol Educ Book. 2019; 39 :115-121. doi: 10.1200/EDBK_238919
3. Cilliers L. Wearable devices in healthcare: Privacy and information security issues. Health Inf Manag. 2020;49(2-3):150-156. doi:10.1177/1833358319851684
4. Kim, T.H., Wang, Y., Oliver, C.R. et al. A temporary indwelling intravascular aphaeretic system for in vivo enrichment of circulating tumor cells. Nat Commun. 2019; 10(1): 1478 doi: 10.1038/s41467-019-09439-9
5. TriNav™ Infusion System. TriNav. Accessed July 15, 2021. https://bit.ly/3ihogf1.
6. Continuous Infusion with Your Elastomeric Pump. Memorial Sloan Kettering Cancer Center. Accessed July 15, 2021. https://bit.ly/3z3MlwG.