Investigation of neoadjuvant gemcitabine plus cisplatin-based triplet regimens on biliary tract cancer with possible lymph node metastasis.

INTRODUCTION: Biliary tract cancer (BTC) is rare. The treatment outcomes in patients with lymph node (LN) metastasis diagnosed by FDG-PET or a biopsy-who are considered to be 'biologically borderline resectable'-are poor. However, perioperative treatment is still under development. Recently, gemcitabine plus cisplatin (GC)-based triplet regimens for unresectable BTC have been developed. We applied GC-based triplet therapy in BTC with LN metastasis.

METHODS: We administered GC plus S-1 therapy (GCS) or nab-paclitaxel therapy (GCnP) to 30 patients with LN metastasis diagnosed by FDG-PET or a biopsy (GC-based triplet group). A dataset of BTC with FDG-positive LNs, previously used for an analysis of the diagnosis and treatment outcomes according to FDG uptake, was used as a control (upfront surgery group, n = 19).

RESULTS: GCS and GCnP were used by 22 and 8 patients, respectively. The median treatment period was 79 days, the objective response rate was 47 %, the tumor control rate was 87 %, and 22 patients underwent R0 resection (73 %). The groups showed no significant differences with the exception of the FDG uptake by the main tumor. The three-year overall survival (OS) rates in the GC-based triplet and upfront surgery groups were 45.4 % and 15.8 %, respectively (P = 0.0052); there were no significant differences in progression-free or recurrence-free survival. A sub-analysis showed that normalized CA19-9 levels provided better survival than non-normalized CA19-9 levels.

CONCLUSION: Neoadjuvant GC-based triplet regimens could provide survival benefits in BTC with LN metastasis diagnosed by FGD-PET or a biopsy. CA19-9 normalization may be useful for indicating surgery.