Advances of Microneedles for Cancer Diagnosis and Therapy

As the global incidence of cancer continues to rise, the need for innovative and precisive alternatives to conventional diagnostic and therapeutic methods has become increasingly urgent. Microneedles (MNs), comprising arrays of micron-scale projections, have emerged as a platform that provides a painless and minimally invasive system for interstitial fluid analysis and transdermal drug delivery. This technology demonstrates potential in cancer diagnostics through continuous biomarker monitoring using integrated biosensors, while enabling controlled release of chemotherapeutics, photothermal/photodynamic, and immunotherapeutic agents. Over the past decades, significant advancements in technology, materials, and medical applications have been achieved in the MN field, which have attracted increasing attention of reseachers. Currently, several MN-based strategies registered on ClinicalTrials.gov are actively investigating their applications in medince, positioning them as a promising new tool for cancer treatment and diagnosis. This review offers a comprehensive summary of the classification, design, fabrication materials, and techniques of MNs, along with their medical applications in cancer diagnosis, therapy, and the management of cancer-associated pain and hair loss. Furthermore, this review summarized ongoing clinical trials in investigating MN-based therapies for cancer patients. And challenges, future perspectives of applying MNs in cancer theranostics are also presented.