Utilization behaviour is thought to occur because an action is initiated when an object is seen, but patients with DES lack the central executive control to inhibit acting it out at inappropriate times.Perseveration is also often seen in patients with DES. Perseveration is the repetition of thoughts, behaviours, or actions after they have already been completed. For instance, continually blowing out a match, after it is no longer lit is an example of perseveration behaviour. There are three types of perseveration: continuous perseveration, stuck-in-set perseveration, and recurrent perseveration. Stuck-in-set perseveration is most often seen in dysexecutive syndrome. This type of perseveration refers to when a patient cannot get out of a specific frame of mind, such as when asked to name animals they can only name one. If you ask them to then name colours, they may still give you animals. Perseveration may explain why some patients appear to have obsessive-compulsive disorder. Comorbid disorders
DES often occurs with other disorders, which is known as comorbidity. Many studies have examined the presence of DES in patients with schizophrenia. Results of schizophrenic patients on the Behavioural Assessment of the Dysexecutive Syndrome (BADS) test (discussed below) are comparable to brain injured patients. Further, results of BADS have been shown to correlate with phases of schizophrenia. Patients in the chronic phase of the disorder have significantly lower scores than those who are acute. This is logical due to the similarities in executive disruptions that make everyday life difficult for those with  schizophrenia and symptoms that form DES.
In particular, HER2 is overexpressed in 13–22% of patients with gastric cancer. Of note, HER2 overexpression in gastric neoplasia is heterogeneous and comprises a minority of tumor cells (less than 10% of gastric cancers overexpress HER2 in more than 5% of tumor cells). Hence, this heterogeneous expression should be taken into account for HER2 testing, particularly in small samples such as biopsies, requiring the evaluation of more than one bioptic sample. Radiation
Radiation therapy (also called radiotherapy) may be used to treat stomach cancer, often as an adjuvant to chemotherapy and/or surgery. Lymphoma
MALT lymphomas can often be fully treated by treating an underlying H. pylori infection. This results in remission in about 80% of cases. Prognosis
The prognosis of stomach cancer is generally poor, because the tumor has often metastasized by the time of discovery, and most people with the condition are elderly (median age is between 70 and 75 years) at presentation. The average life expectancy after being diagnosed is around 24 months, and the five-year survival rate for stomach cancer is less than 10%.Almost 300 genes are related to outcomes in stomach cancer, with both unfavorable genes where high expression is related to poor survival and favorable genes where high expression is associated with longer survival times. Examples of poor prognosis genes include ITGAV, DUSP1 and P2RX7. Epidemiology
Worldwide, stomach cancer is the fifth most-common cancer with 952,000 cases diagnosed in 2012. It is more common both in men and in developing countries.