Preoperative evaluation of the longitudinal spread of extrahepatic bile duct cancer using multidetector computed tomography

Practice guidelines for managing extrahepatic biliary tract cancers

Backgrounds/Aims

Reported incidence of extrahepatic bile duct cancer is higher in Asians than in Western populations. Korea, in particular, is one of the countries with the highest incidence rates of extrahepatic bile duct cancer in the world. Although research and innovative therapeutic modalities for extrahepatic bile duct cancer are emerging, clinical guidelines are currently unavailable in Korea. The Korean Society of Hepato-Biliary-Pancreatic Surgery in collaboration with related societies (Korean Pancreatic and Biliary Surgery Society, Korean Society of Abdominal Radiology, Korean Society of Medical Oncology, Korean Society of Radiation Oncology, Korean Society of Pathologists, and Korean Society of Nuclear Medicine) decided to establish clinical guideline for extrahepatic bile duct cancer in June 2021.

Methods

Contents of the guidelines were developed through subgroup meetings for each key question and a preliminary draft was finalized through a Clinical Guidelines Committee workshop.

Results

In November 2021, the finalized draft was presented for public scrutiny during a formal hearing.

Conclusions

The extrahepatic guideline committee believed that this guideline could be helpful in the treatment of patients.

Accuracy and limitations of preoperative assessment of longitudinal spread of perihilar cholangiocarcinoma

OBJECTIVE

Although surgical resection offers the only chance of cure of perihilar cholangiocarcinoma and R1 resection has a poor prognosis, there is no consensus on optimal preoperative assessment of its longitudinal spread. We aimed to establish the optimal means of achieving this goal.

METHODS

This was a retrospective, single-center study of 61 patients who had undergone multi-detector row computed tomography, endoscopic retrograde cholangiography, intraductal ultrasonography, and mapping biopsy prior to resection of perihilar cholangiocarcinomas in our institute from January 2010 and December 2021.

RESULTS

The most accurate single methods for assessing longitudinal spread were intraductal ultrasonography and mapping biopsy (both 72.1%). A combination of all four assessment methods was accurate in 51 (83.6%) of our patients. Independent risk factors for inaccuracy were Bismuth-Corlette Type IV and high histologic-grade tumors. The R0 resection rate was higher with accurate than inaccurate assessments (90.2% vs. 30.0%, P < 0.001). R0 resection was associated with significantly better relapse-free survival than R1 resection (P = 0.006). However, overall survival did not differ between these groups.

CONCLUSION

Preoperative assessment of longitudinal spread of perihilar cholangiocarcinomas by four different modalities is optimal, achieving 83.6% accuracy and a 90.2% R0 resection rate.

Current Status and Recent Update of Imaging Evaluation for Peri-Hilar Cholangiocarcinoma

간문주변부의 해부학적 복잡성으로 인해 간문주변부 담관암은 그 진단과 치료가 어려운 질환으로 알려져 있다. 간문주변부 담관암이 의심되는 환자에 있어서, 영상 검사는 이상 소견의 발견 및 감별 진단, 종양의 종축 침범 부위의 파악, 인접 혈관 침범과 원격 전이 유무의 파악, 그리고 최종적으로 수술적 절제 가능 유무의 평가에 있어 핵심적인 역할을 하고 있다. 이 종설에서는 간문주변부 담관암의 분류 및 종양의 평가를 위해 권고되는 표준 영상 검사의 기법과 간문주변부 담관암의 전형적인 영상 소견에 대해 기술할 예정이다. 종축 방향의 종양 침범 파악, 인접 혈관 침범 및 원격 전이 유무의 평가에 있어서 각 영상 검사 소견과 그 진단능에 대해 논의할 예정이다. 이후 전통적인 절제 가능성 평가의 개념에 대해 고찰하고, 최근의 경향을 소개한다.

Radiologic Evaluation and Structured Reporting Form for Extrahepatic Bile Duct Cancer: 2019 Consensus Recommendations from the Korean Society of Abdominal Radiology

Radiologic imaging is important for evaluating extrahepatic bile duct (EHD) cancers; it is used for staging tumors and evaluating the suitability of surgical resection, as surgery may be contraindicated in some cases regardless of tumor stage. However, the published general recommendations for EHD cancer and recommendations guided by the perspectives of radiologists are limited. The Korean Society of Abdominal Radiology (KSAR) study group for EHD cancer developed key questions and corresponding recommendations for the radiologic evaluation of EHD cancer and organized them into 4 sections: nomenclature and definition, imaging technique, cancer evaluation, and tumor response. A structured reporting form was also developed to allow the progressive accumulation of standardized data, which will facilitate multicenter studies and contribute more evidence for the development of recommendations.

The Likely Sites of Nodal Metastasis Differs According to the Tumor Extent in Distal Bile Duct Cancer

BACKGROUND

In the revised Japanese and Worldwide TNM classification of distal bile duct cancer, the lymph node status is defined as N0 or N1 without reference to the tumor location or extent, according to the presence/absence of metastasis to the regional lymph nodes.

METHODS

Data of 94 patients with distal bile duct cancer who had undergone pancreaticoduodenectomy were reviewed retrospectively. In formalin-fixed specimens, we measured the longitudinal lengths from the papilla to the lower and upper margins of the tumor, in order to investigate the correlation of the tumor extent with the likely sites of nodal metastasis.

RESULTS

The frequencies of metastasis to the posterior pancreaticoduodenal nodes (7.1 %) and superior mesenteric artery nodes (0.0 %) were significantly lower in the cases in which the length from the papilla to the lower margin of the tumor was ≥30 mm. The frequencies of nodal metastasis to the common hepatic artery nodes (0.0 %) and hepatoduodenal ligament nodes (6.7 %) were significantly lower in the cases in which the length from the papilla to the upper margin was <40 mm.

CONCLUSION

The likely sites of nodal metastasis differ according to the extent of the tumor in cases of bile duct cancer.

A Longitudinal Computed Tomography Imaging in the Diagnosis of Gallbladder Cancer

Background/Aim. To assess whether the diagnostic power of longitudinal multiplanar reformat (MPR) images is superior to that of conventional horizontal images for gallbladder cancer (GBC). Methods. Between 2006 and 2010, a total of 54 consecutive patients with preoperatively diagnosed gallbladder neoplasms located in gallbladder bed were analyzed. These patients underwent cholecystectomy with resection of the adjacent liver parenchyma. The patients were divided into the GBC group (n = 30) and the benign group (n = 24). MPR images obtained by preoperative multidetector row CT (MDCT) were assessed. Results. Mucosal line was more significantly disrupted in GBC group than that in benign group (93% [28/30 patients] versus 13% [3/24], p < 0.001). Maximum (9.3 [4.2-24.8] versus 7.0 mm [2.4-22.6], p = 0.29) and minimum (1.2 [1.0-2.4] versus 1.3 mm [1.0-2.6], p = 0.23) wall thicknesses on a single MPR plane did not differ significantly; however, the wall thickness ratio (max/min) differed significantly (6.8 [1.92-14.0] versus 5.83 [2.3-8.69], p = 0.04). Partial liver enhancement adjacent to tumor on longitudinal images was more common in GBC (40.0% [12/30 patients] versus 12.5% [3/24], p = 0.03). Mucosal line disruption was the most reliable independent predictor of diagnosis (odds ratio, 8.5; 95% CI, 5.99-28.1, p < 0.001). Conclusion. Longitudinal MPR images are more useful than horizontal images for the diagnosis of GBC.

Surgical strategy for bile duct cancer: Advances and current limitations

The aim of this review is to describe recent advances and topics in the surgical management of bile duct cancer. Radical resection with a microscopically negative margin (R0) is the only way to cure cholangiocarcinoma and is associated with marked survival advantages compared to margin-positive resections. Complete resection of the tumor is the surgeon’s ultimate aim, and several advances in the surgical treatment for bile duct cancer have been made within the last two decades. Multidetector row computed tomography has emerged as an indispensable diagnostic modality for the precise preoperative evaluation of bile duct cancer, in terms of both longitudinal and vertical tumor invasion. Many meticulous operative procedures have been established, especially extended hepatectomy for hilar cholangiocarcinoma, to achieve a negative resection margin, which is the only prognostic factor under the control of the surgeon. A complete caudate lobectomy and resection of the inferior part of Couinaud’s segment IV coupled with right or left hemihepatectomy has become the standard surgical procedure for hilar cholangiocarcinoma, and pylorus-preserving pancreaticoduodenectomy is the first choice for distal bile duct cancer. Limited resection for middle bile duct cancer is indicated for only strictly selected cases. Preoperative treatments including biliary drainage and portal vein embolization are also indicated for only selected patients, especially jaundiced patients anticipating major hepatectomy. Liver transplantation seems ideal for complete resection of bile duct cancer, but the high recurrence rate and decreased patient survival after liver transplant preclude it from being considered standard treatment. Adjuvant chemotherapy and radiotherapy have a potentially crucial role in prolonging survival and controlling local recurrence, but no definite regimen has been established to date. Further evidence is needed to fully define the role of liver transplantation and adjuvant chemo-radiotherapy.

Diagnostic accuracy of multidetector-row computed tomography for hilar cholangiocarcinoma

BACKGROUND AND AIM

The aim of this study was to investigate the diagnostic reliability of multidetector-row computed tomography (MDCT) for the evaluation of tumor spread in hilar cholangiocarcinoma.

METHODS

Images obtained from a 16-detector row scanner of 22 patients were interpreted. The diagnostic accuracy of longitudinal ductal spread, vertical invasion (including hepatic parenchyma), and lymph node metastasis was assessed with reference to histopathological findings.

RESULTS

The location of the tumor was correctly diagnosed in 95% of cases (21/22), but in five of these cases, the cut end of the intrahepatic bile duct was positive, resulting in 77% diagnostic accuracy for longitudinal spread. Among the patients with a negative bile duct surgical margin, there was a significant difference in the measurement of tumor spread between MDCT and microscopic investigation (P < 0.001). For vertical invasion, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of MDCT were 69%, 100%, 100%, and 69% for the liver parenchyma, respectively. The sensitivity, specificity, PPV, and NPV of MDCT for lymph node metastasis were 50%, 75%, 43%, and 80%, respectively.

CONCLUSIONS

The diagnostic accuracy of MDCT for tumor location and vertical invasion was satisfactory, but ductal spread was underestimated in comparison with microscopic measurements.