Review for 10.1186/s12876-022-02424-5 (2022)

Title: Risk factors and predictive nomograms for early death of patients with advanced
hepatocellular carcinoma: a large retrospective study based on the SEER database
Version: 3 Date: 01 Apr 2022
Reviewer's report:
The authors performed a retrospective study on the SEER database with the aim of finding risk
factors and creating predictive normograms for early death in patients with HCC.
The study idea is good, however the manuscript needs substantial revisions. Review of language
and structure are extremely necessary for the viability of the publication.
Here are my comments/suggestions/questions:
1. My main suggestion is to completely revise the language of the manuscript. Sentences are
constructed in a confusing way and with grammatical errors. I will punctuate some of the phrases
that caught my attention below, but I recommend a general review.
2. In the background section, results subsection, I suggest exchanging some words that are
misused in the context. "Strict screening conditions" can be replaced by "application of selection
criteria". "Finally" can be removed each time it has been used.
3. In the same subsection mentioned above, please include statistical data (such as C index and
AUC, for example) and the risk factors found.
4. In the background section the phrase "which leads to the five-year survival rate of advanced
HCC is only 8.1%" is constructed in a confusing way.
5. In the background section, in the phrase "have the opportunity to perform surgical resections,
most commonly including liver transplantation, surgical resection, and radiofrequency ablation",
the word surgical resections is being used twice with different meanings.
6. In the background section the authors cite that "according to the data, which was collected
from the SEER database, the 1-year survival rate of patients with stage IV HCC was merely
15.6%, and approximately 57% of patients died within 3 months, which was defined as early
death." I suggest looking for references to these numbers or citing them only in results.
Furthermore, the definition of early death must be placed only in methodology and not in
background.
7. In the background section, please include the primary objective of the study in the last
paragraph. In addition, the paragraph describing the SEER database should be included in the
discussion.
8. In methodology, please include the word "patients" in the exclusion criteria, which do not
have a defined subject.
9. In the methodology, acronyms are used that should be expanded (such as AFP). Also please
reference the TNM system for the staging.
10. In the methodology section, the authors mention that "Main results: patients with stage IV
HCC often live for less than 3 months.". In this session, the objective is to describe the variables
collected and not to describe the results found. Please rephrase.
11. In the statistical analysis session, the phrase "The variables selected from the multivariate
logistic regression analysis were considered to have odds ratio (OR) with 95% confidence
interval (CI) and have p-values." is constructed in a confusing way.
12. In statistical analysis, as patients are divided into groups, I suggest performing statistical
analysis together with descriptive analysis (such as chi-square and t-test or its non-parametrics).
13. The authors cite the use of R software for the analyses, however they do not clarify the
libraries used. In order to allow replicability this information must be added. In addition, it is
possible to have different data packages in SEER, authors should clarify which package they
had access to.
14. Throughout the manuscript the authors do not represent the thousands separator consistently
(the comma is used sometimes and sometimes not).
15. In the results session the terms "rigorous screening process" and "screened out" should
be changed. I suggest using "selection criteria" and "selected". I also suggest again not using
"finally".
16. In the results section the phrase "3271 (62.8%) patients in stage IVB occurred early death"
is poorly constructed and confusing.
17. Authors report results using the word "about". These results are exact numbers and this word
should not be used, as the numbers displayed should be the exact numbers found.
18. For the results session, I suggest following the latest guidelines and reporting races with the
first letter in capital.
19. In the results section, the authors mention that "Patients with tumors larger than 50mm were
more than twice as likely as those with tumors larger than 50mm". The unit of comparison is
not mentioned.
20. In the results section avoid using terms like "some of them had bone metastasis". The
objective in this session is to present the exact results and without interpretations.
21. In the results session, the phrase "It has been reported that the division of young liver cancer
was bounded by <40 years old, which is why we chose 40 years old as the age cut-off point"
should be included in the methodology and not in results.
22. In the results session, the phrase "It has been reported that the division of young liver cancer
was bounded by <40 years old, which is why we chose 40 years old as the age cut-off point"
should be included in the methodology and not in results.
23. In the results section, in sentences like "Tables 2 and 3 described" I suggest using the terms
in the present tense and not in the past tense.
24. In the results section in the sentence "the net benefit rate was 1.0%~78%; in stage IVB
patients, it was 1.0%~85%." the authors mean that the range goes from 1 to 78/80%? I believe
there is an error.
25. In the discussion, in the sentence "The brain was one of the most likely sites for metastasis
in patients with advanced HCC" the term "was" should be replaced by "is".
26. The tables have several variables with NA. Please include in the discussion session
information about why this occurred and what its implications are for the study.
27. In the discussion, include the novelty of the study and its impacts on clinical practice (such
as describing the application and use of normograms by oncologists).