Treatment outcomes of gemcitabine alone versus gemcitabine plus platinum for advanced biliary tract cancer: a Korean Cancer Study Group retrospective analysis

A Systematised Literature Review of Real-World Treatment Patterns and Outcomes in Unresectable Advanced or Metastatic Biliary Tract Cancer

BACKGROUND

Biliary tract cancers are rare aggressive malignancies typically diagnosed when the disease is metastatic or unresectable, precluding curative treatment.

OBJECTIVE

We aimed to identify treatment guidelines, real-world treatment patterns, and outcomes for unresectable advanced or metastatic biliary tract cancers in adult patients.

METHODS

Databases (MEDLINE, Embase, Cochrane Database of Systematic Reviews) were systematically searched between 1 January, 2000 and 25 November, 2021, and supplemented by hand searches. Eligible records were (1) treatment guidelines and (2) observational studies reporting real-world treatment outcomes, for unresectable advanced or metastatic biliary tract cancers. Only studies performed in the UK, Germany, France, Australia, Canada and South Korea were extracted, to moderate the number of records for synthesis while maintaining representation of a wide range of biliary tract cancer incidences.

RESULTS

A total of 66 relevant unique full-text records were extracted, including 16 treatment guidelines and 50 observational studies. Among guidelines, chemotherapies were most strongly recommended at first line (1L); the combination of gemcitabine and cisplatin (GEMCIS) was recommended as the standard of care in 1L. Recommendations for systemic chemotherapy in the second line (2L) conflicted because of uncertainties around survival benefit. Guidelines on further lines of treatment included a range of locoregional modalities and stenting or best supportive care without providing clear recommendations because of data paucity. Fifty observational studies reporting real-world treatment outcomes were extracted, of which 25 (50%) and 9 (18%) reported outcomes in 1L and 2L, respectively; 22 (44%) reported outcomes for treatments described as 'palliative'. In 1L, outcomes for systemic chemotherapy were most frequently described (23/25 studies), and GEMCIS was the most common systemic chemotherapy used (10/23 studies) in line with guidelines. Median overall survival with 1L systemic chemotherapy was < 12 months in most studies (16/23; range 4.7-22.3 months). Most 2L studies (10/11) described outcomes for systemic chemotherapy, most commonly for fluoropyrimidine-based regimen (5/10 studies). Median overall survival with 2L systemic chemotherapy was < 12 months in 5/10 studies (range 4.9-21.5 months). Median progression-free survival was reported more rarely than median overall survival. Some studies with small sample sizes or specifically selected patient populations (e.g. higher performance status, or patients who had already responded to treatment) achieved higher median overall survival.

CONCLUSIONS

At the time of this review, treatment options for unresectable advanced or metastatic biliary tract cancers confer poor real-world survival. For over a decade, GEMCIS remained the 1L standard of care, highlighting the lack of therapeutic innovation in this indication and the urgent unmet need for novel treatments with improved outcomes in this aggressive condition. Additional observational studies are needed to further understand the effectiveness of currently available treatments, as well as newly available therapies including the addition of immunotherapy in the evolving treatment landscape.

Efficacy and safety of chemotherapy with or without targeted therapy in biliary tract cancer: A meta-analysis of 7 randomized controlled trials

The systematic treatment based on gemcitabine plus cisplatin is recommended as the current standard chemotherapy for unresectable or metastatic biliary tract cancers. However, the exact benefits from the recognized regime are still dismal. We thus elicit this study in an attempt to analyze whether targeted therapy coupled with various chemotherapy could produce improvement of survival benefits. The clinical trials were searched electronically from databases till July 2016 published in English and Chinese. Nine hundred and sixty-four patients from 7 trials were identified in our analysis. The overall analysis achieved a significantly higher overall response rate (ORR) among the patients treated with targeted drugs plus chemotherapy than chemotherapy alone (OR=1.87; 95% CI: 1.37-2.57; P=0.000), but failed in the overall progression-free survival (PFS) [mean difference (MD)=0.63; 95% CI:-0.45-1.72; P=0.26] and overall survival (OS) (MD=-0.67; 95% CI:-2.54-1.20; P=0.49). In the sub analysis, better ORR was obtained with the addition of EGFR (OR=1.75; 95% CI: 1.20-2.56; P=0.004) and VEGFR (OR=2.5; 95% CI: 1.28-4.87; P=0.007) targeted therapy. Furthermore, the sub analysis of EGFR target showed an significant improvement on PFS (MD=1.36; 95% CI: 0.29-2.43; P=0.01). No significant differences were observed in the incidences of neutropenia (OR=1.37; 95% CI: 0.89-2.12), thrombocytopenia (OR=1.40; 95% CI: 0.83-2.39), anemia (OR=1.21; 95% CI: 0.62-2.38), peripheral neuropathy (OR=1.52; 95% CI: 0.81-2.88), increased AST/ALT (OR=1.40; 95% CI: 0.82-2.39) as well as fatigue (OR=1.65; 95% CI: 0.96-2.84) in either of the treatment groups. In conclusion, better ORR associated with chemotherapy combined with targeted therapy (both targeting EGFR and VEGF) is found in the present meta-analysis without the cost of increased unacceptable toxicities, but regretfully not for the OS. The sub-analysis of targeting EGFR instead of VEGF obtains a superior PFS. Otherwise, there is no statistically significant difference in the overall PFS between the combination regime and chemotherapy alone. Given the paucity of favorable data, we need further studies to characterize optimal targeted agents to confirm the potential value to biliary tract cancer.

Advanced biliary tract cancer: clinical outcomes with ABC-02 regimen and analysis of prognostic factors in a tertiary care center in the United States

BACKGROUND

Gemcitabine plus cisplatin (GC) is currently the standard regimen for advanced biliary tract cancers (BTC) based on the outcomes in ABC-02 trial. Multiple factors can affect outcomes in these patients. This retrospective review evaluates the University of Cincinnati experience with GC in advanced intrahepatic (IHC)/extrahepatic cholangiocarcinoma (EHC) and gall bladder carcinoma (GBC).

METHODS

In this study approved by University of Cincinnati IRB, retrospective analysis of advanced BTC patients seen between 01/2008 and 01/2015 was done. Kaplan Meyer method was used to calculate progression free survival (PFS), and overall survival (OS). Cox model was used to test the association between baseline variables and OS/PFS, adjusting for gender and age at diagnosis. Patients were identified using ICD code for BT tumors, 26 patients met inclusion criteria: histologically proven advanced BTC that received GC as their initial chemotherapy. GC was given as per ABC-02 protocol with appropriate modifications until disease progression or unacceptable toxicities.

RESULTS

Median age at diagnosis was 62 years (range, 31-81 years). Eighteen (69%) were IHC, 5 EHC, 3 GBC, 61% male, 73% whites. Performance status (PS): 0-1: 69%, PS 2: 31%. Baseline CA19-9 data was available for 21 patients, (range 1 to 69,543), and abnormal CA19-9 was seen in 14 patients (54%). PFS was 4.5 months (95% CI: 3.1-8.9 months) and OS was 10.5 months (95% CI: 7.9-18.8 months). OS at 6 and 12 months was 69% (18/26) and 42% (11/26). Thirty-eight percent (10/26) received 2nd line chemotherapy, of these 9/10 received 5FU based chemotherapy. Eleven percent (3/26) received 3rd line chemotherapy. Increase in baseline carcinoembryonic antigen (CEA), alanine aminotransferase, alkaline phosphatase (ALP) and total bilirubin was associated with increased risk of death while increase in baseline CEA and ALP was associated with increased risk of progression (P valve <0.05). In the group of patients who had all three major risk factors (PS ≥2, CEA >3, and stage IVb), the median survival was 2.9 months (95% CI: 2.6-9.3 months), which was significantly worse compared to rest of the population [median 18 months (95% CI: 5.4-19.5 months), P<0.01].

CONCLUSIONS

Our data supports the use of GC as a first line regimen for advance BTC in a non-clinical trial setting. Results are comparable to those reported in ABC-02 trial, despite inclusion of PS 2 patients whom constituted 31% of our population. In the patient population studied, baseline CEA and liver function test appeared able to predict response to GC in advanced BTC. Patients with all three high risk factors (PS ≥2, CEA >3, and stage IVb) did poorly and may need careful selection prior to initiating chemotherapy.

ABT737 enhances cholangiocarcinoma sensitivity to cisplatin through regulation of mitochondrial dynamics

Cholangiocarcinoma responses weakly to cisplatin. Mitochondrial dynamics participate in the response to various stresses, and mainly involve mitophagy and mitochondrial fusion and fission. Bcl-2 family proteins play critical roles in orchestrating mitochondrial dynamics, and are involved in the resistance to cisplatin. Here we reported that ABT737, combined with cisplatin, can promote cholangiocarcinoma cells to undergo apoptosis. We found that the combined treatment decreased the Mcl-1 pro-survival form and increased Bak. Cells undergoing cisplatin treatment showed hyperfused mitochondria, whereas fragmentation was dominant in the mitochondria of cells exposed to the combined treatment, with higher Fis1 levels, decreased Mfn2 and OPA1 levels, increased ratio of Drp1 60kD to 80kD form, and more Drp1 located on mitochondria. More p62 aggregates were observed in cells with fragmented mitochondria, and they gradually translocated to mitochondria. Mitophagy was induced by the combined treatment. Knockdown p62 decreased the Drp1 ratio, increased Tom20, and increased cell viability. Our data indicated that mitochondrial dynamics play an important role in the response of cholangiocarcinoma to cisplatin. ABT737 might enhance cholangiocarcinoma sensitivity to cisplatin through regulation of mitochondrial dynamics and the balance within Bcl-2 family proteins. Furthermore, p62 seems to be critical in the regulation of mitochondrial dynamics.