Failure patterns after curative resection for intrahepatic cholangiocarcinoma: possible implications for postoperative radiotherapy

Nodal recurrence mapping and clinical target volumes after resection of intrahepatic cholangiocarcinoma or combined hepatocellular-cholangiocarcinoma

Background

Scarce evidence exists for clinical target volume (CTV) definitions of regional lymph nodes (LNs) in intrahepatic cholangiocarcinoma (iCCA) or combined hepatocellular-cholangiocarcinoma (cHCC-CCA). We investigated the mapping pattern of nodal recurrence after surgery for iCCA and cHCC-CCA and provided evidence for the nodal CTV definition.

Methods

We retrospectively reviewed the medical records of patients with iCCA or cHCC-CCA who underwent surgery between 2010 and 2020. Eligibility criteria included patients pathologically diagnosed with iCCA or cHCC-CCA after surgery and a first recurrent event in regional LNs during follow-up. All recurrent LNs were registered onto reference computed tomography images based on the vascular structures to reconstruct the node mapping. Fifty-three patients were eligible. LN regions were classified into four risk groups.

Results

Hepatic hilar and portal vein-vena cava were the most common recurrent regions, with recurrence rates of 62.3 % and 39.6 % (high-risk regions), respectively. Recurrence rates in the left gastric, diaphragmatic, common hepatic, superior mesenteric vessels, celiac trunk, and paracardial regions ranged from 15.1 % to 30.2 % (intermediate-risk regions). There were fewer recurrences in the para-aortic (16a1, a2, b1) and splenic artery and hilum regions, with rates <10 % (low-risk regions). No LN recurrence was observed in the para-oesophageal or para-aortic region (16b2) (very low-risk regions). Based on node mapping, the CTV should include high- and intermediate-risk regions for pathologically negative LN patients during postoperative radiotherapy. Low-risk regions should be included for pathologically positive LN patients.

Conclusion

We provide evidence for CTV delineation in patients with iCCA and cHCC-CCA based on recurrent LN mapping.

Mechanism of postoperative recurrence and metastasis of intrahepatic cholangiocellular carcinoma and clinical prevention and treatment strategy

Intrahepatic cholangiocellular carcinoma is a primary adenocarcinoma originating from intrahepatic bile duct epithelial cells. The tumor has no capsule. At the early stage of the tumor, there are infiltration and metastasis along the lymphatic vessels, blood vessels, perineural space, and loose fibrous connective tissue, which are characterized by lymph node metastasis. Due to the absence of characteristic clinical manifestations and the lack of specific molecular markers for early diagnosis, the surgical resection rate is low and the postoperative tumor recurrence and metastasis rate is high. Low efficacy of chemoradiotherapy, molecular targeted drugs, and immunotherapy results in the poor prognosis. Further research of molecular pathology, gene function, and imaging technology can help elucidate the occurrence, recurrence, and metastasis mechanism of intrahepatic cholangiocellular carcinoma to improve its early diagnosis rate and precise clinical staging. Individualized precision treatment and prevention for the risk factors to reduce the recurrence and metastasis rate postoperatively are key to improving the patient prognosis.

Correlation Between Adjuvant Chemotherapy Regimen, Recurrence Pattern and Prognosis of Cholangiocarcinoma After Radical Surgery

Background and Purpose

About 70% of patients with radical surgery Cholangiocarcinoma (CCA) have recurrence and metastasis. There are few studies on the relationship between CCA adjuvant chemotherapy (mono or combined therapy), recurrence pattern (local, regional, distant recurrence) and prognosis [(Disease free survival, DFS), (Overall survival, OS)] after radical surgery. This study focuses on the correlation between CCA adjuvant chemotherapy, recurrence pattern and prognosis.

Methods

The study involved retrospective analysis of data: preoperative hematology, clinical pathology, adjuvant chemotherapy regimens, recurrence pattern, DFS and OS, of 207 patients with CCA. Chi-square test was used to analyze the correlation between related factors and postoperative recurrence. Survival curves were plotted by Kaplan-Meier method, P-values were calculated by Log-rank for univariate analysis, multivariate COX regression method for multivariate analysis.

Results

Using chi-square test, there were correlations between high carbohydrate antigen 19-9 level(CA19-9≥35), vascular invasion, single-agent adjuvant chemotherapy and postoperative recurrences (p=0.04, p=0.04, p=0.02), COX multivariate regression analysis showed that adjuvant chemotherapy (single vs. doublet drug regimen) was an independent prognostic factor for DFS (11.0 vs. 24.6 months, HR=2.88, P=0.01), whereas recurrence pattern (local vs. distant; regional vs. distant) was an independent prognostic factor for OS (31.2 months vs. 20.4 months, HR=0.58, p=0.01; 32.0 months vs. 20.4 months, HR=0.51, p=0.01).

Conclusion

Adjuvant chemotherapy regimen was an independent prognostic factor of DFS, whereas recurrence patterns were independent prognostic factors for OS. adjuvant chemotherapy with doublet drug regimen was correlated with longer DFS, and different recurrence modes affect OS.