Trastuzumab Plus Gemcitabine-Cisplatin for Treatment-Naïve Human Epidermal Growth Factor Receptor 2-Positive Biliary Tract Adenocarcinoma: A Multicenter, Open-Label, Phase II Study (TAB)

PURPOSE

Human epidermal growth factor receptor 2 (HER2) overexpression is seen in 4%-16% of biliary tract cancers (BTCs). We aimed to evaluate the clinical activity of gemcitabine-cisplatin (GC) plus anti-HER2 antibody trastuzumab as initial treatment in HER2-positive BTCs.

METHODS

This study was an investigator-initiated, open-label, single-arm, multi-institutional, phase II trial in adult patients with HER2-positive (defined as immunohistochemistry [IHC] 3+ or IHC 2+ and fluorescent in situ hybridization-positive), treatment-naïve BTCs. The primary end point of the study was 6-month progression-free survival (PFS). Next-generation sequencing was performed on tissue samples to evaluate mutational status.

RESULTS

From March 2020 to August 2022, of the 876 screened patients, 118 (13.4%) were found to have HER2-positive status, of whom 90 were enrolled in the study. Most patients had GBC (n = 96; 96%) with two or more sites of metastatic disease (n = 70; 78%). With a median follow-up of 17.3 (95% CI, 15.22 to 19.32) months, 72 patients had disease progression with a median PFS of 7 (95% CI, 6.2 to 7.8) months. The diagnosis to event 6-month PFS rate was 75.6% (95% CI, 66.6 to 84.6). A complete or partial response was seen in 50 (55.5%) patients and 22 (24.4%) patients had stable disease as the best response to treatment, for an overall disease control rate of 80%. The presence of isolated TP53 mutations was associated with inferior PFS compared with other mutations (TERT promoter, HER2, PIK3CA, etc) or no detected mutations (6.51 v 12.02 v 10.58 months; P < .001).

CONCLUSION

The combination of GC and trastuzumab achieved its primary end point of improving PFS compared with historical data in the treatment-naïve HER2-positive BTC. Evaluating additional mutations such as TP53 and PIK3CA along with HER2 testing may help to preferentially select patients for anti-HER2 therapy in the future (Clinical Trial Registry India number: CTRI/2019/11/021955).

Perioperative Modified FLOT Versus EOX in Locally Advanced Resectable Gastric and Gastro-Oesophageal Junction Adenocarcinoma: Results of a Matched-Pair Analysis

BACKGROUND AND OBJECTIVES

There is limited real-world data on the efficacy of 2-weekly cycles of docetaxel, oxaliplatin, leucovorin, and fluorouracil (FLOT) compared to epirubicin, oxaliplatin, and capecitabine (EOX) as perioperative therapy in esophagogastric adenocarcinomas (EGAC).

METHODS

The data of 611 patients with EGAC treated with perioperative chemotherapy and planned for curative resection between January 2013 and December 2019 were retrieved. Patients receiving EOX and a dose-modified version of FLOT (mFLOT) were evaluated. A 1:1 matching, using age, tumour location, signet ring histology, and Eastern Cooperative Oncology Group performance status, without replacement was performed by using nearest neighbour matching method. The primary endpoint of the study was 3-year event-free survival (EFS).

RESULTS

A total of 593 patients (261 with EOX and 332 with mFLOT) were matched. One hundred and nighty-eight patients (76%) and 285 patients (86%) in the EOX and mFLOT cohorts underwent curative resection, respectively (p = 0.002). With a median follow-up of 35 and 53 months, respectively, the primary outcome of 3-year EFS was statistically superior in patients receiving mFLOT as compared to the EOX regimen (60% vs. 39%; p < 0.001). There was a greater incidence of grade 3 and grade 4 neutropenia (neoadjuvant: 18% vs. 2%; p < 0.001, adjuvant: 18% vs. 1%; p = 0.001) and febrile neutropenia (neoadjuvant: 8% vs. 1.1%; p < 0.001, adjuvant: 6% vs. 0; p = 0.001) with mFLOT.

INTERPRETATION AND CONCLUSION

mFLOT is associated with improved resection rates and survival in comparison to EOX as perioperative therapy in gastric adenocarcinomas in this large real-world cohort, with manageable increase in clinically relevant toxicities such as grade 3 and grade 4 febrile neutropenia and neutropenia.

Gemcitabine, Cisplatin, and Nab-Paclitaxel as a First-Line Therapy for Advanced Biliary Tract Cancers

INTRODUCTION

Locally advanced, inoperable, or metastatic gallbladder cancers (GBC) are treated with either gemcitabine-platinum combinations or gemcitabine alone based on physician discretion. However, the combination of gemcitabine, cisplatin, and nab-paclitaxel (GCNP) has shown increased response rates and prolonged survival in a phase II trial of biliary tract patients.

MATERIALS AND METHODS

Consecutive series of patients diagnosed with locally advanced (liver infiltration > 5 cm, large nodes at porta, abutting duodenum), inoperable, and metastatic biliary tract patients between January 2018 and August 2022 were evaluated for first-line chemotherapy GCNP, in the multidisciplinary joint clinic (MDJC). The primary endpoint was ORR, and the major secondary endpoint was event-free survival (EFS).

RESULTS

A total of 142 patients received GCNP during the specified time period. The median age of the cohort was 52 years (range: 21-79), the majority were females (61.3%), and the majority were GB (81.7%). Response rates were available in 137 patients. Complete response, partial response, and stable disease were seen in 9 (6.3%), 87 (61.3%), and 24 (16.9%), respectively, for an ORR of 67.6% and a clinical benefit rate of 84.5%. The median EFS was 9.92 (95% CI, 7.69-12.14) months. Of the 52 patients in whom GCNP was given with NACT intent for locally advanced GBC, 17 patients underwent surgery (34%).

CONCLUSION

Our study indicates that GCNP leads to improved response rates, increased chances of resectability, and possibly better survival in patients with GBC.