What are the Causes, Symptoms, Prevention types, diagnostics and Treatments of Small intestine cancer?
Small intestine cancer is rare and usually gives nonspecific symptoms.
Small intestine cancer is a disease in which malignant cells form in the different sections of the small intestine: duodenum, jejunum and ileum. These tumours are sporadic and usually give nonspecific symptoms; therefore, it is usual for the diagnosis to be made when they are pretty advanced.
Prevalence and incidence
These tumours represent around 3% of all cancers of the digestive tract (including those of the colon, stomach, and oesophagus) and barely 0.6% of all cancers. It is estimated that its incidence is 14.9 cases per 100,000 inhabitants per year.
This cancer’s cause is unknown, but some risk factors can influence, among which some hereditary syndromes stand out. For example, people with the following diseases have a greater predisposition:
- HNPCC (hereditary non-polyposis colon cancer).
- Peutz-Jeghers syndrome .
- Lynch syndrome.
Other diseases increase the risk of colon and small intestine cancer, such as:
- Crohn’s disease.
- Celiac disease (when it is not controlled and has a long evolution).
- Cystic Fibrosis.
Some risk factors related to lifestyle also contribute to raising the risk. Still, their influence would be less than in colon cancer: poor diet (excess of refined sugars, red meat, etc.), alcohol consumption, and being a smoker. Also, as in other tumours, a healthy lifestyle (with physical exercise and high consumption of fruits and vegetables) plays a protective role.
The signs that show the presence of a small intestine tumour are not transparent or specific, and, in addition, they usually appear in a phase in which the disease is in an advanced state.
The most frequent are:
- Pain in the abdomen is the most frequent and is a cramp-type or intense pain that comes and goes.
- Weight loss.
- Blood in stool.
- When the tumour has grown a lot, it generates intestinal obstruction, which can cause vomiting and diarrhoea to a much lesser extent.
Prevention is fundamentally based on a healthy lifestyle: a healthy diet, not smoking, not drinking alcohol, and exercising.
In addition, if one of the hereditary conditions is mentioned above, although there is no established official protocol, it is advisable to carry out periodic check-ups with specialists.
We can find different types of tumours in the small intestine:
- Adenocarcinoma of the small intestine occurs in the many layers (the most superficial) of the intestine. The most persistent location is in the duodenum; in more than half of the cases, there is a hereditary predisposition. These tumours represent less than half of small intestine cancers, while approximately 98% of colon cancers are adenocarcinomas.
- Carcinoids: are malignant tumours derived from a type of isolated cells of neuroendocrine origin. They are usually found located in the ileum.
- Sarcomas are tumours that affect the submucosal or muscular layer, among them leiomyosarcomas.
- Lymphomas are malignant tumours that affect the small intestine’s lymphocytes (cells that are part of the immune system). The small intestine is the area of the body with the most lymphatic tissue.
This type of disease is usually detected when it is already quite advanced. In case of suspicion, the doctor will perform a complete medical history, physical examination, and a faecal occult blood test. Laboratory studies should include comprehensive basic biochemistry, blood count and liver profile.
There is no ideal diagnostic method for the small intestine, but some of the most effective imaging tests are:
- Upper gastrointestinal endoscopy: allows visualisation of the duodenum.
- Digestive transit is a radiological procedure that allows seeing abnormalities in the intestinal wall by inserting a barium contrast through the patient mouth, which passes through all parts of the intestine.
- Computed tomography (CT) of the abdomen: lesions from 0.5 to 1 cm can be seen in any organ by allowing the entire stomach to be observed.
- Chest CT: Used to check for lung metastases.
- Abdominal MRI.
- PET-CT: marked glucose is subjected to the blood, so the cells in the process of dividing capture more glucose than the rest and, therefore, are more visible on the CT. This increased cellular activity may indicate the presence of tumour cells.
The treatment of this cancer depends on the type of tumour and the stage of the disease:
- In stages I, II and III of adenocarcinomas: surgical treatment (removal or resection of the tumour) is the most used option.
- In stage III tumours (positive nodes): specialists recommend complementing surgical treatment with chemotherapy.
- In stage IV (advanced) tumours, chemotherapy is the standard therapeutic option.
- Small intestine lymphomas are always treated with chemotherapy, just like blood lymphomas.
- The treatment of choice for neuroendocrine tumours and sarcomas is usually surgical.
When treatment ends, regular check-ups are necessary to monitor the patient.
The possibility of the disease recurring is higher during the first few years. In the first three, it is recommended to carry out exams every few months and, from the fourth and fifth year, they could be spaced a little more.
Follow-up tests are usually the following:
- Complete analytics.
- Abdominal ultrasound.
- Chest x-ray.
- CT chest/abdominal.
- Digestive transit.
- Oral endoscopy.
The prognosis of small intestine tumours depends mainly on the type of tumour. Neuroendocrine tumours generally have a very sluggish behaviour, with little local growth. They can metastasise but rarely do so; instead, they are surgically removed as a precaution.
The prognosis for adenocarcinomas is generally worse than when they occur in the colon. However, it may be due to factors intrinsic to this location and because the diagnosis of small intestine tumours is usually later.