User:SydneyFlatt/sandbox

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 * Note: Please use your sandbox to submit assignment # 3 by pasting it below. When uploading your improvements to the article talk page please share your exact proposed edit (not the full assignment 3).


 * Talk Page Template: CARL Medical Editing Initiative/Fall 2019/Talk Page Template

== Hereditary Nonpolyposis Colorectal Cancer. ==

Assignment #2
Wikipedia Assignment Part 2:  Sydney Flatt – 10193512

1) How you searched for a source (search strategy – where you went to find it).

Source:

Giardiello, F.M., Allen, J.I., Axilbund, J.E., Boland, C.R., Burke, C.A., Burt, R.W., Church, J.M., Dominitz, J.A., Johnson, D.A., Kaltenbach, T., et al. (2014). Guidelines on Genetic Evaluation and Management of Lynch Syndrome: A Consensus Statement by the US Multi-Society Task Force on Colorectal Cancer. Gastroenterology 147, 502-526.

Search Strategy : Searched “lynch syndrome diagnosis guideline” on the TRIP database. This source came up as the second hit under “All Secondary Evidence” as a USA Guideline.

2) What potential sources were identified and considered (give examples of 1 or 2).

One identified source was the UpToDate® webpage titled “Lynch syndrome (hereditary nonpolyposis colorectal cancer): Clinical manifestations and diagnosis”.

3) Why the source was chosen (what made it better than other choices).

The source was chosen over the UpToDate® webpage because I did not believe that the information from this tertiary source would be as reliable, due to the fact that UpToDate® information is not strictly evidence based. Authors use a combination of selected literature (not a systematic review of literature) and expert opinions to form the articles. In addition, UpToDate does not share how it performs literature searches, thus it is unknown whether important studies have been missed or overlooked1. In contrast, the article chosen outlines exactly how their literature search was conducted, while using the GRADE and the National Cancer Institute systems to rate the evidence associated with the recommendations made.

4) List at least three reasons why the source that was selected meets Wikipedia’s reliable medical sources (MEDRS) criteria.

-       It is a secondary source of information

-       It is a guideline from a national expert body created by conducting a literature search

-       It is recently published (2014) and up to date

5) How do you plan to use the source for improving the article?

I would firstly like to add a fundamental piece of information, based on what actually classifies an individual as having the diagnosis of Lynch Syndrome (LS). That is that a diagnosis of LS is applied to patients where there is a germline mutation in one of the DNA MMR genes or the EPCAM gene. I think that this needs to be explicitly said in the diagnosis section. Furthermore, I would like to add under what conditions as individual should undergo germline testing, such as all individuals with colorectal cancer, and with abnormal tumor IHC or MSI.

References:

1          Garrison, J. A. UpToDate. J Med Libr Assoc 91, 97-97 (2003).

Proposed Changes:
Diagnosis Section:

A diagnosis of Lynch Syndrome is applied to people with a germline DNA mutation in one of the MMR genes (MLH1, MSH2, MSH6, and PMS2) or the EPCAM gene, identified by genetic testing. Candidates for germline genetic testing can be identified by clinical criteria such as the Amsterdam Clinical Criteria and Bethesda Guidelines, or through tumor analysis by immunohistochemistry (IHC), or microsatellite instability (MSI) testing.

Traditionally, the Amsterdam Clinical Criteria was used to identify candidates for genetic testing to make a diagnosis of Lynch syndrome, however, 2014 guidelines recommend genetic testing for all newly diagnosed cases of colorectal cancer after initial analysis by immunohistochemistry (IHC), or microsatellite instability (MSI) testing.

-It is very true that this basic definition has not been stated in the article. I guess this is a statement as to how much work needs to be done on this page! - I worry that the word 'germline' won't be understood by the non-medical people reading this. It might be better to say something like "Lynch Syndrome is diagnosed when a mutation in one of the MMR genes occurs in all of your cells". I read one good plain language description: "Most people are born with two working copies of the genes responsible for the mismatch repair system, but some people inherit a faulty (mutated) copy of one of the genes. As they have only one working copy they are more likely to lose the function in the mismatch repair system and subsequently develop cancer. This leads to patterns of cancer in a family, which is known as Lynch syndrome." Something along these lines could be considered. - Sentence 2: I would keep this sentence even more general without referencing the 2014 guidelines in particular as this is just one guideline. There are others that say different things. This statement may tie in to Alexa's discussing age-based vs. universal screening.Grnnbearit (talk) 02:47, 21 November 2019 (UTC)Grnnbearit

Sentence 1:
In the Wikipedia article it is unclear what aspect of germline testing specifically classifies an individual as having the diagnosis of Lynch Syndrome. I believe that it is an important fundamental piece of information for readers to tie together the information from the genetics section of the article, and the diagnosis, as this information was not explicitly stated before.

I agree!Grnnbearit (talk) 02:47, 21 November 2019 (UTC)Grnnbearit

Sentence 2:
This sentence was written in order to update outdated information on who is selected for genetic testing. While previously this was based on selection using the Amsterdam clinical criteria, evidence suggests that the Amsterdam II criteria only has a 22% sensitivity, and thus misses a large percentage of individuals with Lynch Syndrome .. This helped form the basis for current guideline suggestions from the US Multi-Society Task Force on Colorectal Cancer to recommend universal genetic testing to identify patients with Lynch Syndrome.

Source:
The following source was used to support the content for both added sentences:

Giardiello, F.M., Allen, J.I., Axilbund, J.E., Boland, C.R., Burke, C.A., Burt, R.W., Church, J.M., Dominitz, J.A., Johnson, D.A., Kaltenbach, T., et al. (2014). Guidelines on Genetic Evaluation and Management of Lynch Syndrome: A Consensus Statement by the US Multi-Society Task Force on Colorectal Cancer. Gastroenterology 147, 502-526.

Sentence 1:
No ambiguity or controversy.

Sentence 2:
Most experts recommend routine tumor-based testing on all colorectal cancers with IHC followed by BRAF testing, or MSI testing before germline testing. However, this standard requires sufficient infrastructure to deal with the genetic results, which are not set in place everywhere. Thus, these guidelines may not always be followed in practice. Nonetheless, these are the current recommendations to be followed where resources exist.

True - many experts and guidelines recommend universal testing but there are still some guidelines advocating for age-based testing due to resources. There are some guidelines, including what is advocated in Ontario, that tumours in patients <70 years be tested. As you rightly state, the optimal universal testing requires sufficient resources and infrastructure. Grnnbearit (talk) 02:52, 21 November 2019 (UTC)Grnnbearit

Critique of Source:
The source used was a very high-quality guideline from a national expert body, the US Multi-Society Task Force on Colorectal Cancer, published in the journal Gastroenterology, with an impact factor of 20.9. This source conducted a systematic search, detailing their search strategy, and used GRADE and the National Cancer Institute systems to rate and evaluate the evidence associated with the recommendations made. This gave me trust in the source being of very high quality and validity. Furthermore, the information included from this source in the Wikipedia article was a strong recommendation with evidence level III and GRADE moderate-quality evidence, thus the evidence was obtained from well-designed and well-conducted cohort or case-control studies.

One weakness of the source was that the article did not explicitly outline how differences regarding inclusions among reviewers were resolved. It was mentioned that they were resolved by “consensus”, but it is not clear exactly what this means. I see this as a potential source of bias, as there is the opportunity for persuasion, coercion, or group-think mentalities to occur here. This may have impacted the recommendations made in this guideline, however I do believe that it was a well-conducted analysis with excellent credentials, thus making me accept and include the information.