ABSTRACT
Objectives:
To construct a
nomogram for prediction of
intrahepatic cholangiocarcinoma (ICC)
lymph node metastasis based on
inflammation-related markers,and to conduct its clinical verification.
Methods:
Clinical and pathological data of 858 ICC
patients who underwent radical resection were retrospectively collected
at 10 domestic
tertiary hospitals in
China from January 2010 to December 2018. Among the 508
patients who underwent
lymph node dissection,207 cases had complete variable clinical data for constructing the
nomogram,including 84
males,123
females,109
patients≥60 years old,98
patients<60 years old and 69
patients were pathologically diagnosed with positive
lymph nodes after
surgery.
Receiver operating characteristic curve was drawn to calculate the accuracy of preoperative imaging examinations to determine
lymph node status,and the difference in overall
survival time was compared by Log-rank test. Partial regression squares and statistically significant preoperative variables were screened by backward stepwise
regression analysis. R
software was applied to construct a
nomogram,clinical
decision curve and clinical influence curve,and Bootstrap
method was used for internal verification. Moreover,retrospectively collecting clinical information of 107 ICC
patients with intraoperative
lymph node dissection admitted to 9
tertiary hospitals in
China from January 2019 to June 2021 was for external verification to verify the accuracy of the
nomogram. 80
patients with complete clinical data but without
lymph node dissection were divided into
lymph node metastasis high-
risk group and low-
risk group according to the score of the
nomogram among the 858
patients. Log-rank test was used to compare the overall
survival of
patients with or without
lymph node metastasis diagnosed by
pathology.
Results:
The area under the curve of preoperative imaging examinations for
lymph node status assessment of 440
patients was 0.615,with a false negative rate of 62.8% (113/180) and a false positive rate of 14.2% (37/260). The median
survival time of 207
patients used to construct a
nomogram with positive or negative postoperative pathological
lymph node metastases was 18.5 months and 27.1 months,respectively (P<0.05). Five variables related to
lymph node metastasis were screened out by backward stepwise
regression analysis,which were combined
calculi,
neutrophil/
lymphocyte ratio,
albumin,
liver capsule invasion and systemic immune
inflammation index,according to which a
nomogram was constructed with concordance index(C-index) of 0.737 (95%CI 0.667 to 0.806). The C-index of external verification was 0.674 (95%CI0.569 to 0.779). The
calibration prediction curve was in good agreement with the reference curve. The results of the clinical
decision curve showed that when the
risk threshold of high
lymph node metastasis in the
nomogram was set to about 0.32,the maximum net benefit could be obtained by 0.11,and the
cost/benefit ratio was 1∶2. The results of clinical influence curve showed that when the
risk threshold of high
lymph node metastasis in the
nomogram was set to about 0.6,the
probability of correctly predicting
lymph node metastasis could reach more than 90%. There was no significant difference in overall
survival time between
patients with high/low
risk of
lymph node metastasis assessed by the
nomogram and those with pathologically confirmed
lymph node metastasis or without
lymph node metastasis (Log-rank testP=0.082 and 0.510,respectively).
Conclusion:
The prediction accuracy of preoperative
nomogram for ICC
lymph node metastasis based on
inflammation-related markers is satisfactory,which can be used as a supplementary
method for preoperative
diagnosis of
lymph node metastasis and is helpful for clinicians to make personalized
decision of
lymph node dissection for
patients with ICC.