Gastric cancer (or stomach cancer) occurs when the growth of a tumor arises in the inner lining of the stomach. It is not a particularly common form of cancer; however, the danger of this form is in its vague initial symptoms that often lead to the misdiagnosis of it as less severe conditions. For example, late stage cancer can often present with symptoms which indicate
peptic ulcer disease – a condition characterized by pain in the upper abdomen provoked by factors such as indigestion.
Due to this conundrum, patients often present with advanced disease at the time of diagnosis, and their prognosis remains poor despite improvements in treatment. The unfortunate fact is that initial confirmation via diagnosis often faces great delays because up to 80% of patients present as asymptomatic during the early stages of the cancer.
The symptoms of gastric carcinoma include:
Persistent indigestion and heartburn
Persistent stomach pain
Nausea and vomiting
When advanced, the symptoms can also include:
Bloody or black stool
Vomiting of meals or blood (larger tumors can inflict varying degrees of obstruction within the digestive tract)
Recognizably enlarged stomach
A double-contrast barium swallow test is a readily available, economical, and non-invasive study which may be carried out at an early stage to determine whether a gastric lesion is present and its malignant status. This gastric study has a specificity of more than 95% in ruling out gastric cancer when an ulcer is found without any malignant characteristics. However, should results be indeterminate – there may be both malignant and benign characteristics - further diagnostic evaluation is deemed necessary.
An upper endoscopy (or esophagogastroduodenoscopy - EGD) is the main diagnostic procedure for those presenting with the aforementioned symptoms in addition to those with multiple risk factors. This involves visualizing the esophagus and stomach lining with the use of an inserted specialized tube equipped with a camera.
This allows instruments to be passed down the endoscope to biopsy any detected abnormalities. Following detection of a suspected tumor through this upper endoscopy, a biopsy may be necessary.
Further evaluation will consist of physical examination to detect enlargement of lymph nodes and/or liver and fluid accumulation in the abdomen (ascites). Additionally, routine blood work, chest X-rays, and an abdominal CT scan are included. Female patients are also encouraged to have a pelvic CT scan.
Genetic predisposition - familial adenomatous polyposis is a definite risk factor.
Age – there is a positive correlation with age.
Gender - twice as many men are affected than women. The rate of mortality is also approximately double in men than women.
Geographical location - the incidence is highest in eastern Asia, eastern Europe, and South America.
Race – the incidence is highest in American blacks and Asians.
Lifestyle and diet appear to have an impact –
High alcohol intake
Excess dietary salt
Inadequate fresh fruit and vegetable consumption
Nitroso compounds (nitrites and nitrates), which are present in food substances and preservatives appear to have an effect.
Other conditions –
Helicobacter pylori infection may result in gastric cancer – it is characterized by inflammation, which causes cellular alterations in the stomach lining.