Review for 10.1186/1471-230X-14-76 (2014)

Reviewer's report
Title:Factors Associated with Mortality Risk for Malignant Colonic Obstruction in
Elderly Patients
Version:1Date:23 December 2013
Reviewer: Preet Paul Singh
Reviewer's report:
Tha authors submit a revised manuscript and report that they have addressed all
the points raised by the reviewers. Some changes have been made, and this has
made the manuscript more clear. Unfortunately, they have answered some
issues only in the answers to reviewer comment, but not reflected those changes
in the manuscript. Also - with no highlights of where the changes were made, its
difficult to even track what changes they have made.
Major issues remain -
1. They have clarified that all patients had CRC. Its still not clear whether patients
were metastatic CRC were excluded or included. Also, if metastatic patients were
excluded, how many of these patients did not carry a diagnosis but presented
with colonic obstruction - and subsequently (on surgery) found to have CRC
(newly diagnosed CRC).
2. Table 4 - what is p-vale of '0'? Please report actual p-value. Its unclear what is
the reference category for the multivariate odds ratio? This needs to be clearly
reported. Also the odds ratio for peritonitis is less than 1 which means having
peritonitis is protective in terms of mortality, which is clearly a mistake.
3. As all patients failed conservative management - I do not think "emergent"
surgical intervention is still correct. Clearly the patients who developed peritonitis
went onto emergent surgery, but not ones who were otherwise stable and did not
have resolution of bowel obstruction at 72 hrs. Also what happened to patients
who presented with signs of peritonitis - were they also conservatively managed
or taken directly to surgery? Patient selection is very confusing. It may be better
to say, that this study looks at subset of patients who underwent urgent surgery
for failure of medical management of bowel obstruction.
4. Methods section should contain how they defined peritonitis. They say
clinically in the answers to reviewers but please make that clear in the
manuscript for the readers too.
5. Com-morbidity and morbidity after operation is confusing. Changing post-op
morbidity to post-op complications has been suggested by both reviewers - and
the authors say they have done it - but this has not been done.
6. Suffocation should be combined with pulmonary complications.
7. Also, please provide some discussion and guidance as to how patients with
left sided obstruction were selected to get SEMS or surgery. These patient
populations may be very different - that is why the earlier suggestion, that a small
table with some comparison of these groups may be important.
8. I would also question the authors' conclusions from this study.
They report- "In order to prevent high mortality, it should be emphasized that in
elderly patients who require operation for colorectal cancer, the operation should
be performed as soon as conditions are optimized and should not be postponed.
When malignant colonic obstruction occurs, identifying these high-risk patients
and treating them promptly rather than delaying or denying surgery is the best
option."
In my opinion. With high 30-day operative mortality (esp with high ASA grade,
peritonitis and Duke stage), it should be discussed with patients an families - and
possibility of palliative care/comfort care should be considered - as "emergent"
surgery for these patients is associated with high mortality. They may have to
rethink the conclusions from the results.
would request the authors to take time and properly revise the article and
understand the reasons why these points are important. Also, when you submit
the revised manuscript - please highlight what changes have been made, so that
it is possible to track those changes. Also, just clarifying some of the reviewer
queries may not be enough - usually if these points are raised by the reviewer,
these clarifications should be added to the manuscript, as readers would likely
need those clarifications too.
Level of interest: An article whose findings are important to those with closely
related research interests
Quality of written English: Acceptable
Statistical review: Yes, and I have assessed the statistics in my report.
Declaration of competing interests:
'I declare that I have no competing interests'