O. Kutlu1, K. Staveley-O’Carroll1, E. R. Camp1, E. Kimchi1 1Medical University Of South Carolina,Division Of Surgical Oncology,Charleston, Sc, USA
Introduction:
Lymph node metastasis (LNM) is one of the strongest prognostic indicators of survival in intrahepatic cholangiocarcinoma (IHCC). Despite the improvements in imaging modalities, sensitivity of CT scan assessment for LNM still is low. The value of regional lymph node dissection for IHCC is an area of debate. Routine nodal dissection has been investigated to aid in prognostication and as a possible preventive measure for disease recurrence. In this study we investigate the incidence of LNM and factors affecting metastasis in a large epidemiological database.
Methods:
A SEER (Survival Epidemiology and End Results) case listing was acquired for histologically proven IHCC diagnosed between 1988-2011. Patients over 18 years of age, who underwent surgical therapy with known tumor size, T-stage, number of lymph nodes dissected, lymph node positivity, location of lymph nodes, M status, type of surgery performed, tumor grade, disease extension and vascular invasion status were selected for analyses. For patients with positive lymph a binary logistic regression analysis was performed with SPSS 21 and factors affecting lymph node positivity were analyzed.
Results:
Of the 9846 patients, 569 fit our criteria of whom 53.6% were female. Mean age was 62.9 years (21-85), mean tumor size was 5.9 cm (0.3-19), and lymph nodes were sampled in 261(45.8%) patients (mean 4.5 nodes, n=1-32). Among the patients who underwent lymph node sampling, 115 (44%) had nodal disease (hepatoduodenal n=110, inferior phrenic n=1, unspecified n=3, combined n=1). Binary regression analysis showed tumor grade, T stage (vascular invasion, extension of the tumor to extrahepatic bile ducts) to be significant factors associated lymph node positivity. The number of lesions, patient age, tumor size, involvement of contiguous sites, presence of metastatic disease and sex were found to be insignificant.
Conclusion:
The number of LNM in this patient cohort was similar to other reports where findings of routine nodal dissections are published. Identification of patients with high risk features such as high grade tumors, vascular invasion and extension to extrahepatic bile ducts may aid in selection of patients for lymph node dissection. Performed at experienced institutions, lymph node dissection may aid in staging of IHCC, however further studies are needed to confirm our findings.