Although finding cures or methods to reverse disease progression are incredibly critical breakthroughs, diagnostic tools can be just as important. That's why researchers at ETH Zurich have developed an implantable sensor to indicate the presence of certain types of cancer by measuring levels of Ca2+ levels in blood. The calcium concentrations allow the sensor to detect hypercalcemia and react by subcutaneously accumulating melanin pigments to for a tattoo (similar in appearance to a large mole). Since many forms of cancer can lead to rising calcium levels in blood, including breast cancers colon cancer, prostate cancer, and lung cancer, the tattoo would just serve as an indication of early stage development of some type of cancer. Additional diagnostic measures would be needed to pinpoint what type of cancer. It doesn't, however, eliminate the need for repeated screenings as it provides a system of continuous monitoring. However, the current prototypes only have an operational lifetime of 1 year before the sensor needs to be replaced.
Though this system has a long way to go before clinical trials in humans would begin, it's exciting to see the new innovative approaches scientists are taking to tackle early detection hurdles. This concept can hopefully also be applied to many other diseases, such as neurodegenerative and hormonal disorders.
Blood calcium concentrations are elevated in several types of cancer, in addition to other diseases. Here, Tastanova et al. used synthetic biology and cell engineering to develop a sensor that detects hypercalcemia. Their implantable sensor consists of cells that express the calcium-sensing receptor and produce melanin in response to sustained elevated calcium in the blood.