(209) Risk Factors for Primary Refractory Disease in Patients with Advanced Biliary Tract Cancer Treated with First Line Chemotherapy

Poster Abstract:

Background:
Biliary tract cancers include cholangiocarcinoma and gallbladder carcinoma, which are both rare and aggressive diseases associated with poor prognosis. Cholangiocarcinoma is further classified based on tumor location as intrahepatic, perihilar, and distal. Although surgery offers a potential cure, disease recurrence rate is high, and most diagnoses occur in later stages where the tumor is unresectable. Chemotherapy remains a major treatment modality. First line chemotherapy for advanced biliary cancers is cisplatin-based chemotherapy but response rate is typically low. Prognosis is poor after first line treatment, and subsequent optimal therapy is unclear. Evaluating risk factors for lack of response to first line chemotherapy may better guide treatment options and understand potential pathogenesis of primary refractory disease.

Objective:
The purpose of our study is to analyze risk factors for primary refractory disease in advanced biliary tract cancer patients treated with first line cisplatin-based chemotherapy to better guide treatment options and understand potential pathogenesis of primary refractory disease.

Methods:
This single-center, retrospective study included adult patients with a diagnosis of advanced, unresectable cholangiocarcinoma or gallbladder carcinoma who have received first line therapy with gemcitabine/cisplatin, gemcitabine/cisplatin/durvalumab or gemcitabine/cisplatin/nab-paclitaxel between January 1, 2018, to August 1, 2023, at University of California, San Francisco. Patients were excluded if they were less than 18 years old, have history of prior malignancies excluding excised non-melanoma and melanoma in situ, have incomplete data and missing documentation, or were enrolled in clinical trials during first line cisplatin-based chemotherapy. Primary refractory disease was defined as patients with disease progression based on first imaging post-chemotherapy initiation. Risk factors reviewed were host-related factors (age, sex, liver function, ethnicity, ECOG status), tumor-related (tumor type, tumor size, tumor differentiation grade, metastases), mutations and biomarkers, lifestyle factors, comorbidities, and early treatment discontinuation due to toxicities. Mann-Whitney U test, Fisher’s exact test, and multivariable regression analysis were performed as statistical analysis for all independent risk factors.

Results:
Results are pending.

Conclusion:
Conclusions are pending.

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2. Rizvi S. et al. Cholangiocarcinoma - evolving concepts and therapeutic strategies. Nat Rev Clin Oncol. 2018 Feb;15(2):95-111. doi: 10.1038/nrclinonc.2017.157. Epub 2017 Oct 10. PMID: 28994423; PMCID: PMC5819599.

3. Wang C, Pang S, Si-Ma H, Yang N, Zhang H, Fu Y, Yang G. Specific risk factors contributing to early and late recurrences of intrahepatic cholangiocarcinoma after curative resection. World J Surg Oncol. 2019 Jan 3;17(1):2. doi: 10.1186/s12957-018-1540-1

4. Jiang, Y. et al. The epidemiological trends of biliary tract cancers in the United States of America. BMC Gastroenterol 22, 546 (2022). https://doi.org/10.1186/s12876-022-02637-8