Laser-induced breakdown spectroscopy for cancer diagnosis and intraoperative feedback

Abstract

Laser-induced breakdown spectroscopy (LIBS) has emerged as a distinctive analytical option in oncologic research because it provides rapid, label-free, minimally destructive, and spatially resolved elemental information from tissues and biofluids with limited sample preparation. In cancer diagnosis, its main attraction does not lie in replacing histopathology with another optical signal, but in adding a chemically informative layer that can be obtained within seconds and can therefore support time-critical decisions. This review focuses on two closely connected directions with the strongest translational relevance, namely cancer diagnosis and intraoperative feedback. First, the analytical basis of oncologic LIBS is examined from the perspective of elemental dysregulation in tumor biology, sample state and analytical window, spectral-variable construction and classification strategy, and the unresolved problems of sensitivity, repeatability, and standardization. Second, representative evidence is assessed across tumor-tissue discrimination, delineation of infiltrative borders and surgical margins, blood-based and fluid-based analysis, and elemental imaging with histopathologic correlation. Third, the review discusses the requirements for clinical implementation, including fiber-integrated and miniaturized instrumentation, real-time feedback and closed-loop control, multimodal integration, and the evidence hierarchy needed for clinical adoption. The published literature shows that LIBS is already capable of distinguishing malignant from non-malignant tissue in several organ systems, identifying clinically relevant gradients at infiltrative margins, and extracting diagnostically useful patterns from serum, plasma, whole blood, bile, and other complex matrices when appropriate preprocessing and modeling are used. At the same time, most studies remain single-center, analytically heterogeneous, and only partially aligned with clinical validation standards. The most realistic near-term role of LIBS is therefore as a rapid adjunct for tissue attribution and margin orientation rather than as a stand-alone replacement for pathology or molecular diagnostics. Progress toward routine use will depend on harmonized sample handling, quantitative and matrix-aware signal correction, patient-level external validation, device miniaturization, and workflow integration in pathology suites and operating rooms.