Long-term responders to palliative chemotherapy for advanced biliary tract cancer.

Abstract

391 Background: Standard palliative chemotherapy (PC) in patients (pts) with Advanced Biliary Tract Cancer (ABTC) since publication of ABC-02 study in 2010 is cisplatin/gemcitabine (cis/gem), with median overall survival (OS) of 11.7 months. Prior to this, institutional standard was gemcitabine/fluoropyrimidine combination. From the ABC-02 study, 8 cycles of PC is standard. Some pts benefit from continuing PC longer than 8 cycles. Methods: Pts treated for ABTC in Princess Margaret Cancer Centre between 06/1987 and 09/2015, receiving > 8 cycles of PC were included for analysis. Data was collected on demographics, clinicopathologic features, PC regimen, toxicities, and survival. Results: Of 553 pts who received PC, 119 pts met inclusion criteria of PC > 8 cycles. Median age was 60 (range 27-80). Site of tumour was ampullary in 11, distal bile duct in 14, gallbladder in 28, intrahepatic in 37, perihilar in 26, and unspecified in 3 pts. 61 (51%) required biliary stenting. 30 (25%) had definitive surgical resection at diagnosis, while 89 (75%) presented with ABTC. First-line PC regimens were cis/gem in 44 and gemcitabine/capecitabine in 62. Other regimens included gemcitabine and 5-fluorouracil alone or combined. Median time on first line PC was 10 months, with median of 12 cycles (range 9-47). 22 pts (19%) had treatment breaks > 8 weeks then restarted same PC. Any tumour shrinkage was seen in 73 pts (61%). The majority of pts discontinued PC due to disease progression (69), however 16 stopped due to toxicity such as thrombocytopenia, neutropenia, fatigue and neuropathy. At time of analysis, 103 pts had progressive disease, with median progression free survival of 11.8 months. 51 and 21 pts received second and third line chemotherapy, respectively. 27 pts are alive; median OS for the whole group was 22 months (95%CI 18.7-27.3 months). Conclusions: A cohort of ABTC pts continued to derive benefit from chemotherapy beyond 8 cycles, with median OS considerably greater than that seen in clinical trials. Toxicities were mostly manageable, with treatment breaks from PC for relief of side-effects observed. Further exploration of factors prognostic and predictive for continued benefit from PC will be explored and updated at presentation.