LAUSR

Flexible electronics has a strong potential to revolutionize the health care sector. Until now, numerous flexible diagnostic or therapeutic devices have been successfully developed. However, tumor treatment remains rather unexplored in the field of flexible electronics. Herein, the electrical and mechanical properties of highly compliant electronics that are advantageous for targeting tumor sites in internal organs are demonstrated. This kind of electronics can be implanted to heat and thereby render the treated tissue susceptible to chemotherapy, radiation, or other available treatments. The proposed device consists of a 6 μm‐thick polymeric foil hosting a heating unit and temperature sensor, capped with a 5 μm‐thick encapsulation layer. Due to its ultrathin nature, it seamlessly conforms to the very soft liver tissue and allows for precisely controlled thermal treatment and remarkable mechanical compliance. Measurements in murine cancer models exhibit a temperature accuracy of 0.1 °C even at a bending radius of 2.5 mm, characteristic of the markedly curved mouse liver tissues. The presented highly compliant device paves the way for handling of exophytic (located at the organ surface) tumor nodules via thermal destruction of tissue, targeted drug release, or enhancement of antitumor immune responses.