The 2019 WHO classification of tumours of the digestive system

The WHO classification of digestive system tumours presented in the first volume of the WHO classification of tumours series, 5th edition, reflects important advancements in our understanding of tumours of the digestive system (Table 1). For the first time, certain tumour types are defined as much by their molecular phenotype as their histological characteristics; however, in most instances histopathological classification remains the gold...