Despite advancements in various imaging modalities, the simple sense of touch has remained among the most-effective means of detecting breast and prostate cancer. But while breast exams and digital rectal exams have proven to be reliable methods of detection, they are subjective in nature. By capturing and quantifying the sense of touch into reproducible, objective data, however, capacitive tactile sensor solutions hold the potential to revolutionize cancer detection.
Much to the physical discomfort of women everywhere, mammography has served as the screening standard for breast cancer detection since the 1970s. But the tide appears to be turning as the practice of routine mammograms has drawn increasing fire in recent years from critics claiming that the risks and drawbacks outweigh the benefits.
“Despite substantial increases in the number of cases of early-stage breast cancer detected, screening mammography has only marginally reduced the rate at which women present with advanced cancer,” according to a study published in the November 22, 2012, issue of the New England Journal of Medicine. “Although it is not certain which women have been affected, the imbalance suggests that there is substantial over-diagnosis, accounting for nearly a third of all newly diagnosed breast cancers, and that screening is having, at best, only a small effect on the rate of death from breast cancer.”
Critics of mammography further question the counterintuitive use of radiation to screen for cancer. And the amount of radiation to which patients are subjected during a mammogram is also often downplayed. In fact, the dosage of radiation absorption from one mammogram is 20 times that from a chest x-ray.
Luckily, mammograms are only one component of an early detection plan. Because cancer cells are harder than normal tissue, clinical and breast self-exams effectively rely on the sense of touch to identify abnormal lumps in breast tissue. And while subjective in nature, self-exams are credited with identifying 70% of breast abnormalities, according to the National Breast Cancer Foundation.
The success of palpation in cancer detection, coupled with the waning enthusiasm for routine mammograms, has prompted the development of a tactile sensor-based solution that captures the sense of touch and translates it into a digital, reproducible, 3-D image. And enabling this unique touch-based solution is Pressure Profile Systems’ TactArray sensor technology.
Designed to be a pain- and radiation-free screening alternative, the SureTouch visual mapping system features a small, handheld probe outfitted with a high-resolution array of miniature pressure sensors. As the clinician runs the SureTouch probe across an uncompressed breast, the tactile pressure sensors convert the measurement of tissue elasticity into an electronic signal, which, in turn, generates a 3-D digital map of lesions within the breast.
If a lump is detected using the SureTouch probe, the system will estimate the size, shape, hardness, and location of the mass. Clinical data indicate that the system is up to four times as sensitive as human palpation in addition to being comparable to ultrasound. Initial studies indicate that the technology may also be more effective than mammography when using pathology as the gold standard.
But breast cancer screening isn’t the only area benefitting from tactile sensor technology. This concept of quantifying the sense of touch through tactile sensing is also making its mark on prostate cancer screening.
As is the case with breast cancer, prostate cancer is frequently first identified because the associated tumors are often hard masses that can be felt when physicians perform routine screening exams. But, in addition to lacking scientific data, the digital rectal exams conducted to check for prostate cancer are often a source of discomfort and embarrassment for patients.
Efforts to replicate the tactile nature of this exam while minimizing patient discomfort and providing an accurate way to characterize the problem have yielded the ProUroScan system. In lieu of the dreaded gloved digit, for example, the system uses a rectal probe equipped with a tactile pressure-sensor array from PPS to palpate the prostate. These tactile sensors serve to measure temporal and spatial changes in the stress pattern that is created when the probe is pressed against the prostate through the rectal wall. These data shed light on the elastic structure of the prostate and generate a digital image of the prostate anatomy in real time to aid in identifying abnormalities in the tissue.
Both the ProUroScan and SureTouch systems capitalize on PPS’s tactile sensor technology with the intention of capturing the power of touch for early detection of certain types of cancer. And thanks to the conformable and flexible attributes of the company’s tactile sensing technology, the manufacturers of the ProUroScan and SureTouch systems were able to develop devices that improved the patient experience while providing a unique solution to cancer screening procedures.