A collaboration between Portuguese and Italian scientists has discovered new subgroups of stomach cancer patients with different disease's characteristics, an information that is hoped will help improving the clinical management of a disease that still kills a dismaying 3 out of 4 patients.
The study by Giovanni Corso and Joana Carvalho from Carla Oliveiras' team and colleagues searched for somatic (acquired after birth) abnormalities in the molecule E-cadherin (an important tumour suppressor), linking these to the patients' disease history. The results led to the identification of several GC groups with different disease characteristics and even survival chances, including one with the worst prognoses of all. This new information is hoped to be the first step towards better therapeutic decisions to improve the patients' quality of life and maybe even their survival. The study comes from the Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP), Portugal and the University of Siena, Italy and will be published in the March edition of the Journal of Clinical Oncology.
Stomach/gastric cancer (GC) is the second deadliest of all cancers, killing 3 quarters of the patients - almost a million people a year. The problem is that the disease not only tends to show no symptoms until is too late, but is also very heterogeneous. What this means is that apparently similar patients can have very different outcomes, making GC not only very lethal but also of difficult clinical management. And even if researchers have discovered much about the disease's triggers and molecular abnormalities, the information often has not been linked to the clinical side of GC, giving it limited value for patient's everyday care.
In an attempt to address these problems, the study by Corso and Carvalho searched for somatic abnormalities in E-cadherin, but correlating these with the patients' disease history. Somatic abnormalities refer to genetic changes that occur after birth, in opposition to inherited abnormalities, which are present at birth. Inherited abnormalities in E-cadherin are the most important cause of hereditary GC, thus the choice of this molecule for the new study.
The work used patients with no inherited E-cadherin abnormalities and from all types of GC.
In fact, GC can be classified according to cancer morphology, behaviour, inheritance and disease manifestation. So, we can have intestinal gastric cancer (when cancer masses develop in the stomach) versus diffuse GC (when there are, instead, invading individual cancerous cells, a type that normally carries worse diagnosis). In terms of occurrence, the disease can be sporadic (when there is no other cases in the family), hereditary (when it exists in the family and the reason is inherited) or familial (if it runs in the family due to some degree of susceptibility combined with non-genetic causes, like for example, eating habits).