Enhancing the pathological diagnosis of oral cancers using broadband ultraviolet photoacoustic microscopy

Conventional histopathological diagnostic methods, such as hematoxylin-eosin (H&E) staining and immunohistochemistry (IHC), face significant challenges in intraoperatively diagnosing early-stage oral cancer and certain cancer types. To address this, we propose a novel pathological diagnostic method based on a broadband ultraviolet photoacoustic microscope (bUV-PAM). This method capitalizes on the unique optical absorption properties of nuclei and high-frequency photoacoustic spectral variations, enabling the simultaneous performance of photoacoustic morphological imaging (PAMI) and photoacoustic spectral analysis (PASA) within 20 minutes. As a result, photoacoustic images of normal and cancerous mouse tissues, including oral squamous cell carcinoma (OSCC) and adenoid cystic carcinoma (ACC), demonstrate strong consistency with their corresponding H&E images. Moreover, the photoacoustic spectral profiles of these tissues exhibit significant differences, validating the effectiveness of PASA in differentiating between normal and cancerous states. Furthermore, PASA rapidly identifies diseases that are challenging to diagnose with H&E staining, such as the transition from normal mouse mucosa tissue to OSCC and the differentiation between OSCC and ACC, as verified by the more time-consuming IHC method. Consequently, the photoacoustic pathological diagnosis method enhances current diagnostic practices, promising to offer crucial support for the rapid intraoperative identification of human early-stage oral cancers and various cancer types.