Next Generation Digital Pathology: Emerging Trends and Measurement Challenges for Molecular Pathology

Round 1

Reviewer 1 Report

This is an excellent review and introduction to this topic and there is little to change in the manuscript and it could be accepted in its present form. My suggestion below is thematic and I think could put a broader perspective on the field and the importance of "classic" optical microscopy.

The missing piece in my assessment is on the integration of new modalities with "classic" modalities. For instance, most molecular pathology is, at a minimum, informed by classical histological stains, especially as the technology emerges. Virtually all published MSI manuscripts have corresponding microscopy at least for qualitative comparison, technologies like NanoString for spatially targeted -omics use a microscope image to guide acquisition directly, etc. I think it is safe to say that optical techniques remain the fundamental link in the spatial domain for many emerging molecular pathology technologies but also the fundamental link to historical evidence. This is  a valuable point for this manuscript to emphasize.

Author Response

Rebuttal: We thank the reviewer for their supportive comments and helpful feedback. We have added a section highlighting the benefits of integrating molecular pathology with classical histology (outlined below)

Integration of molecular pathology with classical histopathology

Molecular pathology can offer many benefits over existing methods such as improved diagnostic accuracy or insight into disease. This does not replace the need for classical histopathology, however. Many of the methods still make use of histological examination either to make comparisons of molecular information to morphological features⁷⁶, or to select the regions for examination⁸⁵. Much, if not all, of the evaluation of the diagnostic accuracy of emerging molecular pathology modalities is based upon a comparison with histology, and there is a wealth of information from historical studies and samples using these methods. Integrating these new technologies, with histology, and bringing together practitioners of molecular pathology with pathologists is a vital step in realising the full potential of these methods in a clinical setting.

Reviewer 2 Report

The paper is focused on relevant topic. The manuscript is clear and presented in a well structured manner. The study is well designed. Results are reported clearly and appropriate. The discussion is adequate with current citations. The conclusions are consistent with the evidence. 

Would recommend to state as a limitation the type of review used as this seems a narrative vs systematic.

Author Response

Rebuttal: We thank the reviewer for their positive feedback. We have altered the description in the abstract to convey that this review is narrative rather than systematic.

Reviewer 3 Report

This paper is a review of digital and molecular pathology (as well as a bit of proteomics and other aspects of specimen analysis). There is no clear message or goal.

It is not clear if the authors meant this to be a “dictionary” but that is more or less what it seems – the authors try to define each aspect of these areas of pathology in three to five sentences.  Many of the sections are simplified to the extreme. There is much emphasis of artefacts but this is true of every biomedical procedure and analysis and is hardly unique to either digital or molecular pathology. Table 1 is confusing as it encompasses many different modalities that area not actually “molecular pathology”. The figures are not helpful.

Author Response

We thank the reviewer for their feedback and criticisms. Our motivation is to introduce the capability of molecular pathology to new users, and the initial abstract has been altered to reflect this. We note that reviewers 1 and 2 both found the review to be useful.

“This narrative review aims to introduce the field of molecular pathology providing a high-level overview of many different methods.”

Since this is aimed at providing a high level-introduction to the methods for new users, an in-depth review of every technique would not be beneficial. However, this review highlights other review articles for each technique that the reader can review in detail.

Round 2

Reviewer 3 Report

None