Review for 10.1186/s12876-024-03241-8 (2024)

Title: Outcome of patients with perihilar cholangiocarcinoma and previous biliary
instrumentation: An observational study
Version: 2 Date: 28 Dec 2023
Reviewer's report:
This study collected data from 106 patients with perihilar cholangiocarcinoma (PHC) treated at
a single center between 2013 and 2017. The article indicates that trans-papillary biliary drainage
(TPBD) for perihilar cholangiocarcinoma carries a risk of cholangitis and should be avoided,
especially without appropriate indication. Additionally, pre-existing TPBD was associated
with treatment delay and poorer overall survival. When biliary drainage is necessary, targeted
percutaneous stent placement is less likely to cause treatment delay or require additional biliary
intervention compared to endoscopic stenting. The authors highlight that clinical and imaging
findings of PHC should prompt evaluation at a cancer referral center before any intervention,
providing meaningful guidance for preoperative biliary drainage in clinical practice.
The following are the reviewer’s comments on certain issues in the article:
1.There are some abbreviations used without their full notations, such as ‘IR’ in Table 1, ‘OR,’
‘NR,’ etc. in the text. Please provide the full expansions of these abbreviations and review for
similar instances throughout the entire manuscript.
2.The surgery, as an undeniable significant influencing factor for the prognosis and survival of
patients with PHC, requires further subgroup analysis to discuss the impact of biliary drainage
on prognosis in the surgery and non-surgery groups. This is because the selected patient cohort
includes both surgical and non-surgical patients, and thus, it would be beneficial to explicitly
clarify the effect of biliary drainage on the prognosis within these subgroups.
3.In clinical settings, PHC patients with biliary obstruction can present with longlasting
cholestasis, acute cholangitis, coagulopathy, or malnutrition, and others require neoadjuvant
therapy or further assessment of comorbidities. Furthermore, scheduling issues due to limited
capacities of operation suites are often a problem in Asia. Given that all these circumstances
preclude early surgery, we are compelled to determine the effectiveness and applicability of
preoperative biliary drainage. Indeed, hyperbilirubinemia is an important cause of mortality
in PHC patients. Therefore, it is necessary to discuss the clinical management strategies and
approaches for this subset of PHC patients in cancer referral centers.
4.The relative effectiveness of percutaneous and endoscopic techniques is an ongoing area of
study and debate. According to the Clinical practice guidelines for the management of biliary
tract cancers of The Japanese Society of Hepato-Biliary-Pancreatic Surgery#endoscopic biliary
drainage #EBD#is the most appropriate procedure with a low risk of complications. Although
EBD is specifically associated with pancreatitis and tube-related cholangitis. This study lacks
relevant clinical data on the survival benefits and clinical complications of EBD and PTBD in
patients with PHC. The conclusions and discussions in this aspect may require additional support
from clinical data.