Clinicopathological features of long-term survivors for advanced biliary tract cancer and impact of the number of lymph nodes involved

Revisiting resectability of biliary tract cancers, in the triplet drug therapy era with immune checkpoint inhibitors

Biliary tract cancers (BTCs) include intrahepatic, perihilar, distal cholangiocarcinoma, gallbladder cancer, and sometimes papillary Vater cancer. The incidence of BTCs varies worldwide (0.3-85.0/100,000 population). In Japan, the incidence is lowest, but it is increasing (22,000 cases/ year). The 5-year overall survival (OS) in patients with localized BTC is approximately 60%, which is better than that in liver or pancreatic cancer, but is < 5% in patients with metastatic cancers. Surgery requires liver and pancreas surgery with vascular reconstruction, and is associated with a high perioperative mortality rate (> 2%) relative to other cancer surgeries (< 1%). As an adjuvant therapy, fluorouracil prodrugs are effective for improving OS (hazard ratio [HR] 0.69-0.81); however, in patients who receive major hepatectomy, the completion rate is reportedly low (60%). Since 2010, gemcitabine + cisplatin (GC) has become the first-line therapy for unresectable lesions. Subsequently, in 2023-2024 three triplet regimens were reported: GC + S-1(tegafur-gimeracil-oteracil), GC + durvalumab (an anti-PD-L1 antibody), and GC + pembrolizumab (an anti-PD-1 antibody). HRs for OS were 0.79-0.83, objective response rates were 27-42% (GC, 15-29%), and tumor control rates were 75-85% (GC, 62-83%) with small increases in adverse events. In this review, considering the eligibility criteria of currently ongoing neoadjuvant studies, we report two borderline resectable cases with a discussion on resectability. Owing to the high-risk nature of the surgery and to avoid early recurrence due to subclinical metastasis during postoperative recovery, these three triplet regimens for unresectable tumors may change the concept of resectability in BTC.

Invasion category-oriented lymph node metastases of cholangiocarcinoma and the prognostic impact

PURPOSE

It was speculated that intrahepatic cholangiocarcinoma (ICC) invasion would influence cancer progression, such as lymph node (LN) metastasis, and the efficacy of LN dissection (LND). The purpose of this study is to evaluate the LN metastatic pattern of intrahepatic cholangiocarcinoma, including the invasion category and prognosis after surgical resection, in order to explore effective LND.

METHODS

We analyzed a prospectively collected cohort for ICC with a previously reported invasion category: hilar type, showing invasion to the main or first branch of Glisson; peripheral type, showing no invasion to less than the third branch; and intermediate type, for all others.

RESULTS

Data from a total of 180 patients who underwent surgical resection were analyzed (LN dissection in 142 (79%)). In single ICC, hilar type had a higher LN metastatic rate than the others (hilar; 23/45 (51%), intermediate; 7/25 (28%), peripheral; 1/34 (3%)). Although the survival with LN metastasis (LN+) was worse, single and hilar/intermediate ICC LN+ had a better survival than peripheral type LN+ (3-year OS: hilar/intermediate 30-37%, peripheral 0%). The most frequent LN metastatic region was the hepatico-duodenal ligament for all invasion categories, and the LN metastatic region was not related to the survival. In peripheral ICC, LND did not affect the survival. By contrast, hilar/intermediate ICC LN+ had a better survival than did peripheral ICC LN+, and the 3-year OS was ≥ 20%.

CONCLUSION

LN metastasis depended on the ICC invasion category in addition to the tumor number, which affected patients' survival and the need for LND. In hilar-type disease, LN dissection may contribute to the survival.

Laparoscopic Hilar Lymph Node Sampling in Patients With Biliary Tract Cancers That are Rarely Associated With Nodal Metastasis

PURPOSE

Among the various types of biliary tract cancer, patients with single, small (<5 cm), peripheral intrahepatic cholangiocarcinoma (ICC), or small (<2 cm) gallbladder tumors (GBTs) rarely develop lymph node (LN) metastasis. We investigated a laparoscopic approach for hilar LN sampling in such cases.

METHODS

Among the 176 patients with biliary tract cancer who were treated from January 2012 to March 2017, 21 (ICC, n=4; GBT, n=17) met the above indications.

RESULTS

All patients were treated by a laparoscopic approach with R0 resection. After determining the pathologic diagnosis, 9 patients with GBT and all 4 patients with ICC underwent laparoscopic LN sampling; the mean numbers of sampled LNs were 2.6 and 7.3, respectively; no patients had metastasis. The mean operating times for GBT and ICC were 223 and 379 minutes, respectively; the mean blood loss was 23 mL and 171 mL. With the exception of 1 patient who developed intrahepatic metastasis of ICC at the opposite liver lobe, all of the patients were recurrence free.

CONCLUSIONS

A laparoscopic approach could be safely applied under our indications.

BRCA/Fanconi anemia pathway implicates chemoresistance to gemcitabine in biliary tract cancer

The BRCA/Fanconi anemia (FA) pathway plays a key role in the repair of DNA double strand breaks. We focused on this pathway to clarify chemoresistance mechanisms in biliary tract cancer (BTC). We also investigated changes in the CD24⁺/44⁺ population that may be involved in chemoresistance, as this population likely includes cancer stem cells. We used three BTC cell lines to establish gemcitabine (GEM)-resistant (GR) cells and evaluated the expression of BRCA/FA pathway components, chemoresistance, and the effect of BRCA/FA pathway inhibition on the CD24⁺/44⁺ population. FANCD2 and CD24 expression were evaluated in 108 resected BTC specimens. GR cells highly expressed the BRCA/FA components. The BRCA/FA pathway was upregulated by GEM and cisplatin (CDDP) exposure. Inhibition using siRNA and RAD51 inhibitor sensitized GR cells to GEM or CDDP. The CD24⁺/44⁺ population was increased in GR and parent BTC cells treated with GEM or CDDP and highly expressed BRCA/FA genes. FANCD2 was related to CD24 expression in resected BTC specimens. Inhibition of the BRCA/FA pathway under GEM reduced the CD24⁺/44⁺ population in MzChA1-GR cells. Thus, high expression of the BRCA/FA pathway is one mechanism of chemoresistance against GEM and/or CDDP and is related to the CD24⁺/44⁺ population in BTC.

Prognostic impact of tumoral and/or peri-tumoral stromal SPARC expressions after surgery in patients with biliary tract cancer

BACKGROUND AND OBJECTIVE

SPARC (secreted protein acidic and rich in cysteine) is a matricellular glycoprotein that modulates interactions between tumoral cells and the peri-tumoralstroma. SPARC induces proliferation and invasion in vitro, and is a poor prognostic factor in several gastrointestinal cancers. Herein, we evaluated the prognostic value of tumoral and stromal SPARC expression in patients with biliary tract cancer (BTC) after surgery.

METHODS

We examined immunohistochemical patterns of SPARC expression in 110 resected BTC specimens and evaluated the prognostic value using prospectively collected data.

RESULTS

SPARC was expressed in tumoral cells in 46 samples (42%) and inperi-tumoralstromain 65 samples (59%). Tumoral SPARC expression was not related to major patient characteristics. Stromal SPARC expression was related to lymph node metastasis, stage, margin status, and tumor location. Overall survival at 5 years after surgery was 34.2%. Stromal SPARC (P < 0.001) and tumoral SPARC (P = 0.048) were associated with poor prognosis. Multivariate analysis revealed invasion into lymphatic system, residual tumor, and stromal SPARC as independent prognostic factors. The hazard ratio for patients with positive stromal SPARC was 3.20 (P < 0.001).

CONCLUSION

SPARC expression inperi-tumoralstroma predicts a poor prognosis for patients with BTC after surgery.

Prognostic significance of the highest peripancreatic lymph node in biliary tract adenocarcinoma

BACKGROUND

Patients with biliary tract adenocarcinoma with nodal involvement have a poor prognosis. There is currently no standardized method for intraoperative lymph node assessment. The current study aimed to determine the prognostic significance of the highest peripancreatic lymph node (HPLN) in biliary tract malignancy.

METHODS

This was a retrospective study of patients undergoing potential curative resection of biliary tract adenocarcinoma from January 1995 through December 2010 who prospectively had intraoperative sampling of the HPLN. The median follow-up was 72.8 months. The primary end points were recurrence-free survival (RFS) and disease-specific survival (DSS).

RESULTS

The rate of HPLN positivity in 110 patients undergoing exploration for potential curative resection was 30 % and did not vary with histologic subtype (gallbladder vs. cholangiocarcinoma). Eighty-five patients underwent complete gross resection. In this subset, median RFS and DSS were 34.3 months (95 % confidence interval [CI] 23.6-not reached [NR]) and 62.4 months (95 % CI 40.8-NR) for HPLN-negative patients, and 9.6 months (95 % CI 4.76-NR) and 20.5 months (95 % CI 7.4-NR) for HPLN-positive patients (p < 0.01), respectively. Median DSS was 14.6 months (95 % CI 9.6-25.4) for patients with unresectable disease. On multivariate analysis, HPLN status was an independent predictor of RFS (hazard ratio 3.73, 95 % CI 1.86-7.45; p < 0.01) and DSS (hazard ratio 3.98, 95 % CI 1.89-8.38; p < 0.01).

CONCLUSIONS

HPLN status is prognostic of RFS and DSS in biliary tract adenocarcinoma. Intraoperative nodal staging by HPLN sampling warrants further investigation in a prospective trial.