A new microscopy technique that takes only a few seconds enables tissue to be viewed in 3D during lung cancer surgery, making it easier to assess whether the tissue is clear. This can cut down the operating time for patients and reduce complications and adverse effects.

09/24/2020 | 3:39 PM

This has been found in research by a multidisciplinary team of respiratory physicians, surgeons and pathologists from the Amsterdam Academic Medical Center led by the VU LaserLaB, which has recently been published in Translational Biophotonics. In current practice, surgeons have to wait for a histopathological analysis of dissected tissue, which can take over half an hour. The new microscopy technique generates images that can be displayed in the operating theatre within one to three seconds.

Real-time assessment of tumour tissue
The fact that the microscopy technique can provide live feedback to surgeons during an operation improves the quality of the surgery and enables healthy tissue to be left in situ. Rapid accurate diagnosis of lung tumour tissue is also vital when selecting treatments for patients. The actual impact of using this technique in the operating theatre is currently being examined.

The researchers used a compact mobile microscope based on second and third harmonic generation (SHG and THG) and two-photon excitation autofluorescence (2PEF) microscopy. The images generated by the microscope were compared with the corresponding standard histopathological images that surgeons normally have to wait for. The microscope provided relevant histopathological information on such things as cellular structures (e.g. tumour cells), collagen and elastin, enabling different types of lung tumour to be identified immediately.

Current techniques
The current techniques for taking lung tissue samples for diagnosis have limitations that often result in large numbers of biopsies being needed: this can make procedures prolonged, thus increasing the risk of complications and discomfort for patients. What is needed, then, is a technique to ascertain quickly whether sufficient lung tissue has been dissected. Also, during surgery to remove lung tumours there is a need for immediate feedback on the dissected tissue in order to decide whether more tissue needs to be dissected. At present, analysing frozen lung tissue is the only way of obtaining rapid feedback during surgery on the nature of the dissected tissue and the excision margins, but this usually takes at least twenty minutes.

Uses in other types of cancer
With this study, PhD student Laura van Huizen of Vrije Universiteit Amsterdam, the first author of the article, and the co-authors have shown that the new microscopy technique is a promising tool for the real-time assessment of lung tumour tissue. This finding is in line with the results of previous research into the use of this technique in the case of brain tumours. The research has been funded under the Dutch Research Council’s Instant Pathology project. The project was also awarded a grant under the European Horizon 2020 research and innovation programme. 

Image caption: Images generated by the microscope (left) compared with histopathology (right). The images show the transition area between remaining alveoli and the tumour core.