Upper gastrointestinal malignancies in 2017: current perspectives and future approaches

The advent of immune checkpoint inhibitors (PD-1, PD-L1 and CTLA-4) has resulted in unprecedented long-term remissions of unresectable cancers. The efficacy of checkpoint inhibitors was recently demonstrated in gastrointestinal malignancies with mismatch repair deficiencies (dMMR). Pembrolizumab became the first tissue-agnostic US FDA-approved drug based on the presence of the predictive biomarker dMMR. In addition, the FDA in 2017 approved pembrolizumab for PD-L1-positive advanced gastric cancer in third-line and second-line hepatocellular therapy. Novel treatment strategies such as using anti-carcinoembryonic antigen (CEA) bispecific T cells have led to remarkable responses in microsatellite instability-low colorectal cancer. Other major breakthroughs in treating upper gastrointestinal malignancies in 2017 are discussed.

Second-line therapy in advanced biliary tract cancer: what should be the standard?

Biliary tract cancer is a rare malignant tumor. Accordingly, to perform prospective and randomized trials is difficult and the knowledge of its natural history and optimal management remains limited. Chemotherapy is commonly used to improve the outcome and to delay tumor progression in advanced disease. Only recently, cisplatin-gemcitabine combination was identified as the new standard first-line therapy. Despite the outcome improvement, disease progression is a constant and approximately half of patients failing upfront treatment maintain a good performance status and are willing to undergo further treatment. No standard salvage chemotherapy regimen has been identified yet. Experiences of salvage therapy in advanced biliary tract cancer are sparse and yielded disappointing results. Well designed multi-institutional randomized trials are warranted to clarify the role and the activity of a second-line therapy.

[Chemotherapy in gallbladder carcinoma]

Gallbladder cancer is an aggressive tumor. Its incidence varies according to geography. Surgery is the standard treatment for localized stage but there is no standard treatment in metastatic or locally advanced disease. Because of the rarity of bile tract cancer (BTC) and gallblader carcinoma (GBC), most studies have grouped all BTC and GBC together, and there are very few GBC-specific studies. In addition, there is a paucity of randomized controlled studies in this disease with small numbers of patients and inclusion bias. One randomized trial ABC-02 was well conducted and showed a survival benefit in favor of gemcitabine (GEM)+cisplatin (CDDP), which can be regarded as the standard in locally advanced BTC. Adjuvant therapy after surgical resection is not validated. Understanding the molecular mechanisms of carcinogenesis of GBC has opened the way for the use of targeted therapies. This new treatment would improve survival and quality of life of our patients.