Clinicopathological significance of mucin production in patients with papillary cholangiocarcinoma

Utility of modified pancreaticoduodenectomy (Hi-cut PD) for middle-third cholangiocarcinoma: an alternative to hepatopancreaticoduodenectomy

BACKGROUND

The standard procedure for middle-third cholangiocarcinoma (MCC) is pancreaticoduodenectomy (PD); hepatopancreaticoduodenectomy (HPD) is often performed despite its high risk. There is no clear selection guidance for these procedures.

METHODS

Patients with MCC who underwent HPD or PD were retrospectively evaluated. The conventional PD was modified (mPD) to transect the bile duct beyond or close to the cranial level of the portal bifurcation.

RESULTS

The mPD group (n = 55) was characterized by older age, shorter operation time, less blood loss, and less frequent complications than were observed in the HPD group (n = 34). The median grossly tumor-free margin of the proximal bile duct (GM) was 13 mm vs 20 mm (P = 0.006). Overall survival did not differ significantly between groups (48% vs 53% at 5 years, P = 0.399). Multivariate analysis identified positive surgical margin as a sole independent prognostic factor (hazard ratio, 1.89; P = 0.043), which was statistically associated with GM length. Five-year survival for mPD patients with GM ≥15 mm was significantly better than that for those who had GM <15 mm (69% vs 33%, P = 0.011) and comparable to that of HPD patients (53%, P = 0.450).

CONCLUSION

The mPD may be recommended in patients with MCC, provided that GM ≥15 mm is expected from the preoperative radiological imaging. Otherwise, HPD should be considered.

A clinicopathological reappraisal of intraductal papillary neoplasm of the bile duct (IPNB): a continuous spectrum with papillary cholangiocarcinoma in 181 curatively resected cases

BACKGROUND

Intraductal papillary neoplasm of the bile-duct (IPNB) has recently been further subclassified into "so-called IPNBs" (Type-1) and "narrow-sense papillary cholangiocarcinomas" (Type-2), but their differential diagnosis is challenging. This study aimed to reevaluate Type-1 and Type-2 IPNBs.

METHODS

Consecutive patients who underwent papillary bile-duct tumor resection were included. Using six pathological features (location, mucin secretion, histological architecture, histological type, presence of a low/intermediate-dysplasia component, and proportion of the invasive component), all papillary tumors were scored. Tumors scoring 5-6 were classified as Type-1, 0-1 as Type-2, and 2-4 as Type-Unclassifiable.

RESULTS

The 181 papillary bile-duct tumor patients were divided into three groups, consisting of 12 Type-1, 46 Type-2, and 123 Type-Unclassifiable-gray-zone lesions between Type-1 and Type-2 that constituted the largest proportion of papillary tumors. Type-1 tumors were pathologically the least advanced, while the other types showed gradual advancement. The 5-year survival rate was better for patients with Type-1 tumors than for those with Type-Unclassifiable or Type-2 tumors.

CONCLUSION

The scoring system worked well to delineate a continuous spectrum of pathologic features ranging from Type-1, through Type-Unclassifiable, to Type-2, the latter two being challenging to differentially diagnose. Type-1 is regarded as an early neoplasm of Type-Unclassifiable and Type-2.

Reappraisal of pathological features of intraductal papillary neoplasm of bile duct with respect to the type 1 and 2 subclassifications

The pathological spectrum of intraductal papillary neoplasm of bile duct (IPNB) remains to be clarified. A total of 186 IPNBs were pathologically examined using the type 1 and 2 subclassifications proposed by Japanese and Korean biliary pathologists incorporating a two-tiered grading system (low-grade and high-grade dysplasia), with reference to four subtypes (intestinal [i], gastric [g], pancreatobiliary [pb], and concocytic [o] subtype). IPNBs were classifiable into type 1 composed of low-grade dysplasia and 'high-grade dysplasia with regular structures' (69 IPNBs), and type 2 of 'high grade dysplasia with irregular structures and complicated lesions' (117 IPNBs). Type 1 was more common in the intrahepatic bile duct (78%), whereas type 2 was frequently located in the extrahepatic bile duct (58%). Mucin hypersecretion was more common in type 1 (61%) than in type 2 (37%). IPNBs were classifiable into the four subtypes: 86 iPNBs, 40 gIPNBs, 31 pbIPNBs, and 29 oIPNBs. The four subtypes were histologically evaluable with reference to the type 1 and 2 subclassifications. iIPNB and pbIPNBs were frequently classified as type 2, whereas types 1 and 2 were observed at similar rates in gIPNB and oIPNB. Stromal invasion was almost absent in type 1, irrespective of subtype, but was found in 66 of 117 type 2 IPNBs (P < .01), and postoperative outcome was favorable in IPNBs without invasion compared with IPNBs with invasion (P < .05). The type 1 and 2 subclassifications with reference to the four subtypes may provide useful information for understanding IPNB.

Intraductal Papillary Neoplasm of Bile Duct: Updated Clinicopathological Characteristics and Molecular and Genetic Alterations

Intraductal papillary neoplasm of the bile duct (IPNB), a pre-invasive neoplasm of the bile duct, is being established pathologically as a precursor lesion of invasive cholangiocarcinoma (CCA), and at the time of surgical resection, approximately half of IPNBs show stromal invasion (IPNB associated with invasive carcinoma). IPNB can involve any part of the biliary tree. IPNB shows grossly visible, exophytic growth in a dilated bile duct lumen, with histologically villous/papillary neoplastic epithelia with tubular components covering fine fibrovascular stalks. Interestingly, IPNB can be classified into four subtypes (intestinal, gastric, pancreatobiliary and oncocytic), similar to intraductal papillary mucinous neoplasm of the pancreas (IPMN). IPNBs are classified into low-grade and high-grade based on lining epithelial features. The new subclassification of IPNB into types 1 (low-grade dysplasia and high-grade dysplasia with regular architecture) and 2 (high-grade dysplasia with irregular architecture) proposed by the Japan–Korea pathologist group may be useful in the clinical field. The outcome of post-operative IPNBs is more favorable in type 1 than type 2. Recent genetic studies using next-generation sequencing have demonstrated the existence of several groups of mutations of genes: (i) IPNB showing mutations in KRAS, GNAS and RNF43 belonged to type 1, particularly the intestinal subtype, similar to the mutation patterns of IPMN; (ii) IPNB showing mutations in CTNNB1 and lacking mutations in KRAS, GNAS and RNF43 belonged to the pancreatobiliary subtype but differed from IPMN. IPNB showing mutation of TP53, SMAD4 and PIK3CA might reflect complicated and other features characterizing type 2. The recent recognition of IPNBs may facilitate further clinical and basic studies of CCA with respect to the pre-invasive and early invasive stages.

Expression and Serum Levels of Mucin 5AC (MUC5AC) as a Biomarker for Cholangiocarcinoma: a Meta-analysis

AIM

The potential of biomarkers in detecting early cholangiocarcinoma (CCA) is facilitated by examining CCA-associated proteins from primary studies. One such protein is mucin 5AC (MUC5AC) but inconsistency of reported associations between its expression/serum levels and CCA prompts a meta-analysis to obtain more precise estimates.

METHODS

A literature search yielded 17 included articles where multiple data in some raised the number of studies to 22. We calculated pooled odds ratios (OR) and 95% confidence intervals from negative and positive readings of MUC5AC levels. Data were subgrouped by ethnicity, detection method, sample source, and cancer type.

RESULTS

Outcome in the overall analysis was non-significant but those in the subgroups were. Thus, significant associations (P < 0.001) indicating high MUC5AC levels were found in three subgroups: (i) Thai (OR 8.32) and (ii) serum (OR 4.52). Heterogeneity of these two outcomes (I² = 90-93%) was erased with outlier treatment (I² = 0%) which also modulated the pooled effects (OR 2.48-2.59). (iii) Immunoblot (OR 2.61) had low initial heterogeneity (I² = 2%). Robustness and significant tests for interaction (P_interaction = 0.01-0.02) improved MUC5AC associations with CCA in the Thai population.

CONCLUSIONS

Our pooled effect findings target the biomarker potential of MUC5AC to the Thai population.

Human primary liver cancer organoids reveal intratumor and interpatient drug response heterogeneity

Liver cancer is the fourth leading cause of cancer-related mortality and is distinguished by a relative paucity of chemotherapy options. It has been hypothesized that intratumor genetic heterogeneity may contribute to the high failure rate of chemotherapy. Here, we evaluated functional heterogeneity in a cohort of primary human liver cancer organoid lines. Each primary human liver cancer surgical specimen was used to generate multiple cancer organoid lines, obtained from distinct regions of the tumor. A total of 27 liver cancer lines were established and tested with 129 cancer drugs, generating 3,483 cell survival data points. We found a rich intratumor, functional (drug response) heterogeneity in our liver cancer patients. Furthermore, we established that the majority of drugs were either ineffective, or effective only in select organoid lines. In contrast, we found that a subset of drugs appeared pan-effective, displaying at least moderate activity in the majority of these cancer organoid lines. These drugs, which are FDA approved for indications other than liver cancers, deserve further consideration as either systemic or local therapeutics. Of note, molecular profiles, obtained for a reduced sample set, did not correlate with the drug response heterogeneity of liver cancer organoid lines. Taken together, these findings lay the foundation for in-depth studies of pan-effective drugs, as well as for functional personalized oncology approaches. Lastly, these functional studies demonstrate the utility of cancer organoid drug testing as part of a drug discovery pipeline.

Occult mucin-producing cholangiocarcinoma in situ: a rare clinical case with difficult tumour staging

Background

Mucin-producing cholangiocarcinoma (MPCC) is an uncommon tumour that is clinically characterized by mucin-hypersecretion. Because the initial symptoms of MPCC may be attributed to the viscus mucobilia, the primary tumour mass may potentially be unrecognizable. We report an interesting case of curatively resected occult MPCC in situ.

Case presentation

A 70-year-old man was referred to our hospital with increased levels of biliary enzymes. Multidetector row computed tomography (MDCT) demonstrated a diffuse dilatation of the entire biliary system without evidence of tumour mass. Additionally, there were numerous variably sized cysts throughout the liver. The cyst of S4 was the largest, followed by that of S1, which connected with the right hepatic duct. Endoscopic retrograde cholangiography showed intrabiliary mucus, predominantly in the left hepatic duct, but failed to show a communication of both cysts with the bile duct. We clinically suspected that minute MPCC was present within the S1 cyst and performed left hepatectomy, caudate lobectomy, and resection of the extrahepatic bile duct. Macroscopically, papillary adenocarcinoma in situ was present in the S1 cyst, and a final diagnosis of MPCC originating from the bile duct of the caudate lobe was made.

Conclusions

For MPCC, in practice, we should consider the possibility that this tumour can be occult. In this complicated setting, demonstrating the communication to the responsible dilated duct is a clue to the diagnosis. Multidirectional MDCT images succeeded in specifically demonstrating this communication, which is insensitive to the presence of excessive mucobilia.