Indication of extrahepatic bile duct resection for gallbladder cancer

Impact of longitudinal tumor location on postoperative outcomes in gallbladder cancer: Fundus and body vs. neck and cystic duct, a retrospective multicenter study

Backgrounds/Aims

Systematic investigations into the prognostic impact of the longitudinal tumor location in gallbladder cancer (GBC) remain insufficient. To address the limitations of our pilot study, we conducted a multicenter investigation to clarify the impact of the longitudinal tumor location on the oncological outcomes of GBC.

Methods

A retrospective multicenter study was conducted on 372 patients undergoing radical resections for GBC from January 2010 to December 2019 across seven hospitals that belong to the Daejeon-Chungcheong branch of the Korean Association of Hepato-Biliary-Pancreatic Surgery. Patients were divided into GBC in the fundus/body (FB-GBC) and GBC in the neck/cystic duct (NC-GBC) groups, based on the longitudinal tumor location.

Results

Of 372 patients, 282 had FB-GBC, while 90 had NC-GBC. NC-GBC was associated with more frequent elevation of preoperative carbohydrate antigen (CA) 19-9 levels, requirement for more extensive surgery, more advanced histologic grade and tumor stages, more frequent lymphovascular and perineural invasion, lower R0 resection rates, higher recurrence rates, and worse 5-year overall and disease-free survival rates. Propensity score matching analysis confirmed these findings, showing lower R0 resection rates, higher recurrence rates, and worse survival rates in the NC-GBC group. Multivariate analysis identified elevated preoperative CA 19-9 levels, lymph node metastasis, and non-R0 resection as independent prognostic factors, but not longitudinal tumor location.

Conclusions

NC-GBC exhibits more frequent elevation of preoperative CA 19-9 levels, more advanced histologic grade and tumor stages, lower R0 resection rates, and poorer overall and disease-free survival rates, compared to FB-GBC. However, the longitudinal tumor location was not analyzed as an independent prognostic factor.

Prognostic factors for resected cases with gallbladder carcinoma: a systematic review and meta-analysis

OBJECTIVE

Current meta-analysis was performed to systematically evaluate the potential prognostic factors for overall survival among resected cases with gallbladder carcinoma.

METHODS

PubMed, EMBASE, and the Cochrane Library were systematically retrieved and hazard ratio (HR) and its 95% confidence interval were directly extracted from the original study or roughly estimated via Tierney's method. Standard Parmar modifications were used to determine pooled HRs.

RESULTS

A total of 36 studies with 11 502 cases were identified. Pooled results of univariate analyses indicated that advanced age (HR=1.02, P =0.00020), concurrent gallstone disease (HR=1.22, P =0.00200), elevated preoperative CA199 level (HR=1.93, P <0.00001), advanced T stage (HR=3.09, P <0.00001), lymph node metastasis (HR=2.78, P <0.00001), peri-neural invasion (HR=2.20, P <0.00001), lymph-vascular invasion (HR=2.37, P <0.00001), vascular invasion (HR=2.28, P <0.00001), poorly differentiated tumor (HR=3.22, P <0.00001), hepatic side tumor (HR=1.85, P <0.00001), proximal tumor (neck/cystic duct) (HR=1.78, P <0.00001), combined bile duct resection (HR=1.45, P <0.00001), and positive surgical margin (HR=2.90, P <0.00001) were well-established prognostic factors. Pathological subtypes ( P =0.53000) and postoperative adjuvant chemotherapy ( P =0.70000) were not prognostic factors. Pooled results of multivariate analyses indicated that age, gallstone disease, preoperative CA199, T stage, lymph node metastasis, peri-neural invasion, lymph-vascular invasion, tumor differentiation status, tumor location (peritoneal side vs hepatic side), surgical margin, combined bile duct resection, and postoperative adjuvant chemotherapy were independent prognostic factors.

CONCLUSION

Various prognostic factors have been identified beyond the 8th AJCC staging system. By incorporating these factors into a prognostic model, a more individualized prognostication and treatment regime would be developed. Upcoming multinational studies are required for the further refine and validation.

Clinical significance of extrahepatic bile duct resection for T2 gallbladder cancer using data from the Japanese Biliary Tract Cancer Registry between 2014 and 2018

PURPOSE

The present study aimed to determine whether concomitant extrahepatic bile duct resection (EHBDR) improves the prognosis of patients with T2 gallbladder cancer (GBC).

METHODS

Between 2014 and 2018, 4947 patients with GBC were registered in the National Biliary Tract Cancer Registry in Japan. This included 3804 patients (76.9%) who underwent curative-intent surgical resection; 1609 of these patients had pT2 GBC with no distant metastasis. Of the 1609 patients with GBC, 520 underwent EHBDR and 1089 did not. We compared the patients' backgrounds and disease-specific survival rates between the groups.

RESULTS

The frequency of lymph node metastasis was significantly higher in the EHBDR group than in the non-EHBDR group (38.2% vs. 20.7%, p < .001). In the entire cohort, however, there was no significant difference in disease-specific survival between the two groups (76% vs. 79%, p = .410). The EHBDR group had a significantly higher incidence of postoperative complications (Clavien-Dindo classification grade = 3) (32.4% vs. 11.7%, p < .001). When we focused on the survival of only T2N1 patients who underwent gallbladder bed resection, the prognosis was significantly improved for the EHBDR group (5-year survival rate: 64% vs. 54%, p = .017). The non-EHBDR group was subcategorized into two groups: D2 dissection and D1 dissection or sampling, and survival curves were compared between these subgroups. Although the EHBDR group tended to have a favorable prognosis compared to the D2 group, this difference was not significant (p = .167). However, the EHBDR group had a significantly greater prognosis than the D1 dissection or sampling group (5 year-survival rate: 64 vs. 49%, p = .027).

CONCLUSIONS

The EHBDR may improve the prognosis of patients with T2 gall bladder cancer with lymph node metastases; however, its indication should be carefully determined because of the increased risk of postoperative complications.

Effects of Cystic Duct Margin Involvement on the Survival Rates of Patients With Gallbladder Cancer: A Propensity Score-Matched Case-Control Study

Background In gallbladder cancer (GBC), extrahepatic bile duct (EHBD) resection is selectively performed if gross direct extension or microscopic involvement of the cystic duct margin (CDM) is detected. Although CDM is usually sent for frozen biopsy intraoperatively in most centers, there are no studies regarding the routine use of CDM frozen biopsy irrespective of the tumor location and paucity of literature regarding the impact of CDM status on recurrence-free and overall survival in GBC. The presence of obstructive jaundice in GBC usually indicates the involvement of EHBD or cystic duct-bile duct junction. The present study aimed to analyze the necessity of routine CDM frozen biopsy in patients with resectable GBC without jaundice, regardless of the tumor location. The impact of positive CDM on survival was also evaluated. Methods This retrospective observational case-control study was conducted from May 2009 to March 2021 and included 105 patients with resectable GBC without macroscopic EHBD infiltration and jaundice. Patients were divided into CDM-negative (n=91) and CDM-positive (n=14) groups. Propensity score matching was performed for variables such as performance status, tumor size, tumor-node-metastasis (TNM) stage, and adjuvant chemotherapy. After propensity score matching, 27 patients (CDM-negative=13, CDM-positive=14) were included. The primary outcome was to analyze the role of routine CDM frozen biopsy regardless of tumor location, and secondary outcomes were to study the impact of positive CDM status on survival and evaluate predictive factors for CDM positivity. A subgroup analysis was conducted to assess clinicopathologic characteristics and outcomes of the anatomical location of the tumor. Results Of 105 patients, 91 had negative CDM, and 14 had positive CDM. Among 14 patients with positive CDM, only one patient had a tumor in the fundus/body, and the remaining had a tumor involving the neck. All CDM-positive patients underwent bile duct excision with hepaticojejunostomy. Common bile duct (CBD) involvement was present in 50% of patients with positive CDM in the final histopathological examination. In the matched population, patients with positive CDM had a significantly higher rate of neck tumors (p=0.001). Recurrence-free survival (24 vs. 12 months, p=0.30) and overall survival (24.5 vs. 20 months, p=0.417) were comparable between CDM-negative and CDM-positive groups, respectively. On multivariate analysis, preoperative and intraoperative tumor location were independent predictive factors for CDM positivity. On subgroup analysis, 30 patients had tumor involving the neck of the gallbladder, and the remaining 75 had at the fundus and body of the gallbladder. Neck tumors had inferior recurrence-free survival (17 vs. 30 months, p=0.012) and overall survival (24 vs. 36 months, p=0.048) compared to non-neck tumors. Conclusions Routine use of CDM frozen analysis in patients with resectable GBC without jaundice, regardless of tumor location, can be avoided. It can be selectively preferred in patients with GBC involving the neck since tumor location is found to be an independent predictive factor for CDM positivity. Positive CDM has comparable survival outcomes to negative CDM, providing a similar R0 resection rate and tumor stage. However, neck tumors have a worse prognosis than non-neck tumors.

The Significance of Tumor Locations in Patients with Gallbladder Carcinoma After Curative-Intent Resection

OBJECTIVE

To evaluate the significance of tumor locations in patients with resected gallbladder carcinoma (GBC) and to supply the indication of extra-hepatic bile duct resection (EHBDR) according to tumor locations.

METHODS

Patients with resected GBC from 2010 to 2020 in our hospital were retrospectively analyzed. Comparative analyses and a meta-analysis were performed according to different tumor locations (body/fundus/neck/cystic duct).

RESULTS

Article: A total of 259 patients were identified (neck: 71; cystic: 29; body: 51; fundus: 108). Patients with proximal tumors (neck/cystic duct) were often in a more advanced stage and had more aggressive tumor biological features as well as a worse prognosis compared with those with distal tumors (fundus/body). Moreover, the observation was even more obvious between cystic duct and non-cystic duct tumors. Cystic duct tumor was an independent prognostic factor for overall survival (P = 0.01). EHBDR provided no survival advantage even in those with cystic duct tumor.

META-ANALYSIS

With our own cohort incorporated, five studies with 204 patients with proximal tumors and 5167 patients with distal tumors were identified. Pooled results revealed that proximal tumors indicated worse tumor biological features and prognosis versus distal tumors.

CONCLUSION

Proximal GBC had more aggressive tumor biological features, and a worse prognosis versus distal GBC and cystic duct tumor can be regarded as an independent prognostic factor. EHBDR had no obvious survival advantage even in those with cystic duct tumor and was even harmful in those with distal tumors. Upcoming more powerful well-designed studies are required for further validation.

Heterogeneity of management practices surrounding operable gallbladder cancer - results of the OMEGA-S international HPB surgical survey

BACKGROUND

Gallbladder cancer (GBC) is an aggressive, uncommon malignancy, with variation in operative approaches adopted across centres and few large-scale studies to guide practice. We aimed to identify the extent of heterogeneity in GBC internationally to better inform the need for future multicentre studies.

METHODS

A 34-question online survey was disseminated to members of the European-African Hepatopancreatobiliary Association (EAHPBA), American Hepatopancreatobiliary Association (AHPBA) and Asia-Pacific Hepatopancreatobiliary Association (A-PHPBA) regarding practices around diagnostic workup, operative approach, utilization of neoadjuvant and adjuvant therapies and surveillance strategies.

RESULTS

Two hundred and three surgeons responded from 51 countries. High liver resection volume units (>50 resections/year) organised HPB multidisciplinary team discussion of GBCs more commonly than those with low volumes (p < 0.0001). Management practices exhibited areas of heterogeneity, particularly around operative extent. Contrary to consensus guidelines, anatomical liver resections were favoured over non-anatomical resections for T3 tumours and above, lymphadenectomy extent was lower than recommended, and a minority of respondents still routinely excised the common bile duct or port sites.

CONCLUSION

Our findings suggest some similarities in the management of GBC internationally, but also specific areas of practice which differed from published guidelines. Transcontinental collaborative studies on GBC are necessary to establish evidence-based practice to minimise variation and optimise outcomes.

The role of extra-hepatic bile duct resection in the surgical management of gallbladder carcinoma. A first meta-analysis

OBJECTIVE

To systematically evaluate the clinicopathological and prognostic value of extra-hepatic bile duct resection (EHBDR) in the surgical management of patients with gallbladder carcinoma (GBC), especially in non-jaundiced patients.

METHODS

PubMed, EMBASE and the Cochrane Library were searched up to March 1st 2021 for comparative studies between bile duct resected and non-resected groups. RevMan5.3 and Stata 13.0 software were used for the statistical analyses.

RESULTS

EHBDR did not correlate with a better overall survival (OS) (P = 0.17) or disease-free survival (P = 0.27). No survival benefit was also observed in patients with T2N1 (P = 0.4), T3N0 (P = 0.14) disease and node-positive patients (P = 0.75), rather, EHBDR was even harmful for patients with T2N0 (P = 0.01) and node-negative disease (P = 0.02). Significantly higher incidences of recurrent disease (P = 0.0007), postoperative complications (P < 0.00001) and positive margins (P = 0.02) were detected in the bile duct-resected group. The duration of postoperative hospital stay between the two groups was comparable (P = 0.58). Selection bias was also detected in our analysis that a significantly higher proportion of advanced lesions with T3-4 or III-IV disease was observed in the bile duct-resected group (P < 0.00001). EHBDR only contributed to a greater lymph yield (P = 0.01).

CONCLUSION

EHBDR has no survival advantage for patients with GBC, especially for those with non-jaundiced disease. Considering the unfairness of comparing OS between jaundiced patients receiving EHBDR with non-jaundiced patients without EHBDR, we could only conclude that routine EHBDR in non-jaundiced patients is not recommended and future well-designed studies with more specific subgroup analyses are required for further validation.

Revision Surgery for Incidental Gallbladder Cancer-Challenging the Dogma: Ideal Timing and Real-World Applicability

BACKGROUND

There is a lack of consensus on the ideal time interval and therapeutic value of revision surgery in patients with incidental gallbladder cancer (iGBC) in the context of multimodality management.

PATIENTS AND METHODS

Retrospective analysis of an institutional database of patients with iGBC who underwent surgery from January 2010 to December 2019 was performed. Patients who underwent upfront surgery were divided into four time interval groups: A, B, C, and D (< 6 weeks, 6-10 weeks, 10-14 weeks, and > 14 weeks, respectively).

RESULTS

A cohort of 517 patients planned for revision surgery was analyzed. Overall, 382 (73.9%) patients underwent upfront surgery while 135 (26.1%) were given neoadjuvant treatment. With median follow-up of 18 months, 2-year overall survival (OS) was 66% and disease-free survival (DFS) was 52.6%, with inferior survival outcomes observed with advancing stage and presence of residual disease on final histopathology. Propensity score-matched analysis after matching for pT stage of cholecystectomy specimen suggested a survival benefit for patients operated between 10 and 14 weeks in terms of OS (p = 0.049) and DFS (p = 0.006). Patients with locally advanced iGBC at presentation had superior OS when operated after neoadjuvant therapy [3-year estimated OS of 59.9% vs 32.3%, respectively (p = 0.001)].

CONCLUSIONS

Revision surgery is at best the most accurate staging procedure guiding timely initiation of systemic therapy. Patients with iGBC operated between 10 and 14 weeks after initial cholecystectomy tend to have favorable survival outcomes, although this depends on final disease stage. Revision surgery should also be offered to all patients presenting at any later point of time, if deemed operable.

The significance of anatomic tumor location in gallbladder cancer

BACKGROUND AND OBJECTIVES

Current management guidelines recognize the impact of hepatic versus peritoneal sided gallbladder cancers (GBC) on survival. However, no data exist regarding the significance of anatomic tumor location within the gallbladder.

METHODS

We retrospectively analyzed all GBC that underwent surgical resection with curative intent in our health system from 2007 to 2017. We evaluated the effect of anatomic pathologic tumor location (fundus/body, neck, and multifocal) on clinicopathologic, perioperative, and oncologic outcomes.

RESULTS

About 97 patients met criteria; 63% fundus/body, 22% multifocal, and 15% neck. Compared with fundus/body, neck tumors more frequently presented with preoperative jaundice (53% vs. 13%, p < .001), were smaller (20 mm vs. 30 mm, p = .068) and had significantly more biliary tree invasion (33% vs. 13%, p = .030) on histopathology. Although tumor characteristics (pTNM stage, liver invasion, lymphovascular invasion, prognostic nutritional index, and grade) were similar, neck tumors had significantly higher rates of R0 resection (53% vs. 11%, p < .001). Rates of adjuvant therapy were similar. Median PFS was similar between cohorts (p = .356). However, median overall survival (OS) was significantly shorter in neck (21 months) than fundus/body tumors (NR > 109 months), p = .015.

CONCLUSIONS

Neck tumors were rare, small and more likely to result in jaundice secondary to biliary tree invasion. Despite higher R0 resection rates, these tumors had significantly worse OS.

Causes of misdiagnosis and missed diagnosis and therapeutic and preventive strategies for unexpected gallbladder carcinoma

Laparoscopic cholecystectomy (LC) has been widely used in the treatment of gallbladder diseases. Since the indications for operation are constantly expanding, the intraoperative or postoperative incidence of unexpected gallbladder carcinoma (UGC) is gradually increasing. The incidence of UGC in LC and open cholecystectomy is 2.09% and 0.91%, respectively. Because gallbladder carcinoma is often accompanied by gallstones or inflammation and lacks specific clinical manifestations, imaging features, and specific serum tumor markers, the preoperative diagnostic rate of gallbladder carcinoma is only 30%, and 30% of cases of gallbladder carcinoma are diagnosed intraoperatively or postoperatively. Pathological T stage, lymph node metastasis, and gallbladder rupture are independent risk factors for the prognosis of patients with UGC. Preoperative imaging combined with serological tumor markers, intraoperative careful exploration, and rapid pathological examination are important measures to reduce the misdiagnosis and missed diagnosis of UGC. For patients with benign gallbladder diseases with a high potential of canceration, performing cholecystectomy in time and strictly grasping the indications for preserving gallbladder for benign gallbladder diseases are important preventive measures to reduce the incidence of UGC.

Scoring System to Predict pt2 in Gallbladder Cancer Based on Carcinoembryonic Antigen and Tumor Diameter

BACKGROUND AND AIMS

T2 gallbladder cancer requires lymph node dissection for curative resection, whereas simple cholecystectomy is adequate to treat T1 gallbladder cancer. Hence, this study aimed to develop an accurate scoring system to preoperatively predict pT2 in gallbladder cancer.

MATERIAL AND METHODS

We retrospectively assessed data from 57 patients with suspected gallbladder cancer who underwent curative resection between September 2003 and May 2017. Six with apparent invasion of adjacent organs on preoperative images were excluded. We evaluated preoperative computed tomography, magnetic resonance and endoscopic ultrasonographic images, blood biochemistry, and the maximum standard uptake value in fluorodeoxyglucose-positron emission tomography images. We analyzed whether correlations between preoperative findings and the depth of tumor invasion could predict pT2.

RESULTS

The pathological diagnosis was gallbladder cancer in 30 (58.8%) patients, of whom 21 (69.9%) had pT2 or worse. Multivariate analyses selected carcinoembryonic antigen and tumor diameter as independent predictors of pT2 or worse (odds ratios = 1.741 and 1.098, respectively; 95% confidence intervals = 1.004-3.020 and 1.008-1.197, respectively). A regression formula was created using carcinoembryonic antigen and tumor diameter to calculate pT2 predictive scores. The area under the receiver operating characteristics curve of the pT2 predictive score was 0.873.

CONCLUSION

We created a scoring system to predict pT2 in gallbladder cancer using carcinoembryonic antigen and tumor diameter. The present findings suggested that carcinoembryonic antigen is important for the preoperative evaluation of gallbladder cancer.

BRAZILIAN CONSENSUS ON INCIDENTAL GALLBLADDER CARCINOMA

BACKGROUND

Incidental gallbladder cancer is defined as a cancer discovered by histological examination after cholecystectomy. It is a potentially curable disease. However, some questions related to their management remain controversial and a defined strategy is associated with better prognosis.

AIM

To develop the first evidence-based consensus for management of patients with incidental gallbladder cancer in Brazil.

METHODS

Sixteen questions were selected, and 36 Brazilian and International members were included to the answer them. The statements were based on current evident literature. The final report was sent to the members of the panel for agreement assessment.

RESULTS

Intraoperative evaluation of the specimen, use of retrieval bags and routine histopathology is recommended. Complete preoperative evaluation is necessary and the reoperation should be performed once final staging is available. Evaluation of the cystic duct margin and routine 16b1 lymph node biopsy is recommended. Chemotherapy should be considered and chemoradiation therapy if microscopically positive surgical margins. Port site should be resected exceptionally. Staging laparoscopy before reoperation is recommended, but minimally invasive radical approach only in specialized minimally invasive hepatopancreatobiliary centers. The extent of liver resection is acceptable if R0 resection is achieved. Standard lymph node dissection is required for T2 tumors and above, but common bile duct resection is not recommended routinely.

CONCLUSIONS

It was possible to prepare safe recommendations as guidance for incidental gallbladder carcinoma, addressing the most frequent topics of everyday work of digestive and general surgeons.

Landscape of distant metastasis mode and current chemotherapy efficacy of the advanced biliary tract cancer in the United States, 2010-2016

BACKGROUND

The distant metastasis (DM) mode and treatment efficacies in the advanced biliary tract cancer (BTC) were obscure, and a credible evaluation is urgently needed.

METHOD

A total of 6348 advanced BTC patients (ICC, intrahepatic cholangiocarcinoma, n = 1762; PHCC, perihilar cholangiocarcinoma, n = 1103; GBC, gallbladder cancer, n = 2580; DCC, distal cholangiocarcinoma, n = 538; AVC, carcinoma of Vater ampulla, n = 365) were enrolled from the Surveillance, Epidemiology, and End Results (SEER) database. Propensity score matching (PSM) process was carried out for less bias.

RESULT

The proportion of M1 patients in each subtype at first diagnosis was 26.4% (ICC), 37.2% (PHCC), 41. 0% (GBC), 24.5% (DCC), and 12.7% (AVC), and the constitution of DM sites in different subtypes varied apparently. Moreover, the survival of metastasis sites was different (P < .05 in all the subtypes) where the multi-metastasis and distant lymph node (dLN) only always indicated the worst and best prognosis, respectively. Chemotherapy presented the most significant survival impact with the lowest hazard ratio by multivariate cox model and still provided a survival improvement after PSM (all P < .001) in all subtypes. However, the median months manifested different between patients with and without chemotherapy among the subtypes (ICC, from 5 to 9; PHCC, from 6 to 10; AVC, from 4 to 9; GBC, from 6 to 7; DCC from 6 to 8).

CONCLUSION

We provided a landscape about the detailed DM mode of the advanced BTC in a large population, found the survival differences among DM sites, and revealed the different chemotherapy efficacies in the BTC subtypes.

Indications for extrahepatic bile duct resection due to perineural invasion in patients with gallbladder cancer

Background

The indications for extrahepatic bile duct (EHBD) resection remain a major controversy in the surgical management of patients with gallbladder cancer. On the other hand, perineural invasion (PNI) was reported as an important factor in patients with gallbladder cancer because gallbladder cancer cells frequently spread to the tissues surrounding the EHBD via perineural routes. We assessed the correlation of PNI with clinicopathological factors in patients with gallbladder cancer to elucidate EHBD resection indications specifically in patients with PNI.

Methods

This retrospective study assessed the PNI status of 50 patients with gallbladder cancer who underwent curative resection and examined the correlation between the presence of PNI and clinicopathological factors.

Results

Thirteen patients (26%) were PNI positive. PNI was significantly correlated with male sex, proximal-type tumor, lymphatic and vascular invasion, and advanced T stage. Multivariate analysis found that PNI positivity (p < 0.001), lymphatic invasion (p = 0.007), and nodal stage (p < 0.001) were independent prognostic factors. PNI was never observed in patients with stage T1 cancer. Conversely, PNI was detected rarely in distal-type tumors, all of whom developed various types of recurrences.

Conclusions

These results clearly demonstrated the prognostic impact of PNI in patients with gallbladder cancer. We suggest that EHBD resection in combination with cholecystectomy may not be useful for distal-type tumors from a perspective of PNI.

Essential updates to the surgical treatment of biliary tract cancer

Biliary tract cancer, which includes intrahepatic cholangiocarcinoma, extrahepatic bile duct cancer, gallbladder cancer, and ampullary cancer, is an intractable disease with a dismal prognosis. Prognosis is particularly poor in cases involving vessels or lymph nodes. Hepatobiliary pancreatic surgeons worldwide have consistently focused on improving surgical treatment, perioperative management, and chemotherapy to improve the outcomes of these diseases. There has been significant progress even in the last 2 years (2017 and 2018), such as promising findings reported by studies on the optimal extent of surgical treatment and multi-institutional randomized controlled trials on adjuvant chemotherapy. We overview the current trends and advancements made in surgical treatment in 2017 and 2018.

Pattern of distant metastases in primary extrahepatic bile-duct cancer: A SEER-based study

Extrahepatic bile duct cancer (EBDC) is a combined type of malignancy mainly consisting of extrahepatic cholangiocarcinoma and gallbladder cancer. Clinically, it is featured with latent symptoms and early metastasis, leading to a poor prognosis. Therefore, this cohort study aimed to depict the possible metastatic patterns of EBDC of diverse sub-types and evaluate the prognostic significance of diverse metastatic destinations with data from the clinical database. Relevant data of total 4061 confirmed EBDC patients diagnosed between 2010 and 2013 from the Surveillance, Epidemiology and End Results (SEER) database was obtained. We applied t test to describe the baseline data of patients included and used chi-square test to compare the distribution of distant metastatic sites. We further adopted odds ratio assess the combined metastatic patterns and compared survival difference of patients with different distal metastasis organ by Kaplan-Meier analysis. We identified totally 4061 patients over 18 years old diagnosed with extrahepatic bile tract malignancies between 2010 and 2013, with clear metastatic status and follow-up data, without primary malignancies. Liver and distant lymph (DL) are the two most common sites as a single metastasis organ. In combined metastasis patterns, bi-organ is more frequent than the other types. Lung is the organ preferentially for bi-organ metastasis, while bone and distant lymph similarly intend to co-metastasize with brain. Distal metastasis in EBDC patients indicates an extremely poor prognosis. According to the final analysis results, malignancies in extrahepatic bile duct exhibit similar metastatic patterns, suggesting that we can regard them as a unity to assess its development. Profound differences exist in distribution of distant extrahepatic metastatic sites and their combinations. Results from our studies would provide some information for follow-up strategies and future studies.