Diagnostic pathways and therapeutic targets of tumours in humans are constantly evolving. Advances in molecular sciences offer new opportunities to clinicians working in this field. Digestive system cancers are common worldwide.

Treatments are more effective when the cancer is detected at an early stage. It can be more of a challenge when the cancer is detected later on. When digestive system cancers are diagnosed, many patients are faced with the question of how long they will survive with this condition and how and how fast they have to be treated. Clinical and pathological examinations help to differentiate tumours in terms of their degree of aggressiveness. This may help to make a treatment decision after a tumour diagnosis and to estimate cancer-specific survival. However, individual risk stratification is also subject to some challenges. A genetic evaluation may be able to answer these clinical questions. Various methodologies can be used for this purpose. These investigations may involve working with tumour tissue, adjacent stroma tissue, and urine or blood samples.

The aim of this Special Issue is to bring together original research articles and review articles that provide new insights into digestive system cancers. Submissions can include current and novel methodologies for prognosis, diagnosis and/or treatments.

Potential topics include but are not limited to the following:

• Molecular pathology and signalling pathways in digestive system cancers
• Tumour microenvironment of digestive system cancers
• Treatment responses and prognosis in digestive system cancers
• Target discovery for digestive system cancers
• Efficacy of drug design and prevention of drug resistance for digestive system cancers
• Targeted therapy for digestive system cancers
• Precision medicine for digestive system cancers
• High-throughput technologies such as omics technologies (genomics, epigenomics, proteomics, metabolomics), microarray and next-generation sequencing for digestive system cancers
• Application of genomic and proteomic databases to improve prognosis, diagnosis and treatments in digestive system cancers