Review for 10.1186/1471-230X-13-9 (2013)

Reviewer's report
Title:Diabetes mellitus impacts risk of macrovascular invasion in patients
undergoing transplantation for hepatocellular carcinoma
Version: 1Date:19 February 2012
Reviewer: Abid Suddle
Reviewer's report:
This is an interesting study based upon a retrospective analysis of a
poespectively collected database. As outlined by the authors, there is
epidemiological data indicating an inceased incidence of Hepaticellular
Carcinoma in diabetic patients and worse outcomes in this patient group.
The diagnosis of diabetes at the time of transplant is not quite as tight as it may
have been if the study had been conducted prospectively. The authors allude to
this point. The study populations appear relatively well matched, although
diabetic patients were older at the time of transplant. This may have implications
for the stage of disease at the time of diagnosis/ transplant.
The radiologic staging at the time of transplant is similar for both groups.
Transplant wait-list times seem reasonably short, although standard deviations
are not given for this parameter. Bridging loco-regional therapy is used with
similar frequency in both groups. Serum AFP is similar for both groups.
My major critisicm of the study relates to pathologic analysis of explanted livers.
We are told that the number of tumours and size of the dominant tumour nodules
is similar for both groups. Size of tumours is known to be a suurogate marker for
the risk of vascular invasion. However, no details are provided regarding the
histologic staging of tumours; ie whether tumours are well, moderately or poorly
differentiated, associated with potential sattelite nodules of associated with
divergent differentiation. These factors are potentially associated with vascular
invasion and /or a higher risk of tumour recurrence.
Allowing for this, the authors have shown a higher risk of macrovascular invasion
in daibetic patients. The risk with daibetes is, perhaps suprisingly, higher than for
total tumour diameter. Post-transplant HCC recurrence was not higher in the
diabetic group, but overall survival was poorer.
In the discussion, the authors outline potential reasons why daibetes would be
associated with macrovascular invasion. Molecular profilling of explanted livers,
in order to determine if diabetes is associated with a different gene signature
profile, would have been interesting. The authors also outline potential limitations
of the study.
Overall, I think the conclusions from the study provide an interesting and
potentially clinically important obsevation which warrants further study for
validation and to provide insight into potential mechanisms.
1. I do not feel the study requires major compulsory revisions.
2. Discretionary reviews. The conclusions from the study may be further
validated if details relating to the full pathologic analysis of explanted livers, as
outlined above, are included.
Level of interest: An article of importance in its field
Quality of written English: Acceptable
Statistical review: Yes, but I do not feel adequately qualified to assess the
statistics.
Declaration of competing interests:
I declare that I have no competing interests