Photoacoustic tomography for assessment and quantification of cutaneous and metastatic malignant melanoma - A systematic review

Background: Photoacoustic tomography (PAT) is an emerging noninvasive imaging technique combining high sensitivity optical absorption contrast, such as melanin, with high-resolution ultrasound for deep tissue imaging. The ability of PAT to provide real-time images of skin structures at depth has been studied for diagnosis of primary and metastatic malignant melanoma (MM). Objective: To provide an overview of the rapidly expanding clinical use of PAT for determination of melanoma thickness and architecture, visualization of metastases in lymph nodes and detection of circulating melanoma cells. Methods: Medline, PubMed, EMBASE, Web of Science, Google Scholar, and Cochrane Library were searched for papers using PAT to assess cutaneous malignant melanoma and melanoma metastases in humans or human specimens. Results: The research resulted in 14 articles which met the search criteria. Conclusions: Results from current studies suggest that PAT is a promising tool for assessing both primary and metastatic malignant melanoma in the clinic. The potential of PAT to noninvasively visualize tumour boundaries, as well as assist in the evaluation of metastatic status, could facilitate more effective treatment, resulting in better clearance and reducing the need for additional biopsies. However, larger and methodologically sound studies are warranted.