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- Exploring cancer care
- Conditions we treat
- Gastrointestinal Cancer
- Small Bowel Cancer
What is small bowel cancer?
Chapter 01
What is small bowel cancer?
The small bowel, which is also called the small intestine, is part of the body’s digestive system. It is a long tube that carries digested food between your stomach and your large intestine (colon).
The small bowel is responsible for:
- digesting and absorbing nutrients from the foods you eat
- producing hormones that help with digestion
- has a role in your body’s germ-fighting immune system, as it contains cells that fight bacteria and viruses that enter your body through your mouth.
Like other cancers, small bowel cancer starts with uncontrolled growth and multiplication of abnormal cells. Over time, these abnormal cells develop into a progressively larger mass which starts to block the small bowel.
What is small bowel cancer
Small bowel cancer (also called small intestine cancer) is an uncommon type of cancer that occurs when cells in the small bowel become abnormal and keep growing and form a mass or lump called a tumour. The type is defined by the cells that are affected.
The most common types of small bowel cancer are:
- Adenocarcinoma – this type of tumour starts in epithelial cells – the mucous-releasing cells that line the inside of the small intestine, often in the duodenum.
- Sarcoma – this type of tumour starts in connective tissue (which support and connect all the organs and structures of the body). Gastro-intestinal stromal tumours (GIST) start in nerve cells anywhere in the small intestine. Leiomyosarcoma starts in muscle tissues in the wall of the small intestine, often in the ileum.
- Neuroendocrine tumours (NETs) – form in neuroendocrine cells inside the small bowel, often in the ileum. The neuroendocrine system is a network of glands and nerve cells that make hormones and release them into the bloodstream to help control normal body functions.
- Lymphoma – form in lymph tissue (part of the immune system which protects the body) in the small intestine, often in the jejunum. Non-Hodgkin lymphoma starts in lymphocytes, a type of white blood cell.
Causes of small bowel cancer
The cause of small bowel cancer is not known in most cases. However, there are several factors that may increase the risk including:
- Genetic factors – some rare, inherited diseases can put people more at risk of small intestine cancer. Examples include Lynch syndrome, familial adenomatous polyposis (FAP) and Peutz-Jeghers syndrome.2,3
- Other factors:
- some small intestine cancers may be linked to Crohn’s disease and coeliac disease2,3
- eating large amounts of animal fat and protein, especially processed meat and red meat2,3
- smoking2,3
- older age – most people diagnosed with small intestine cancer are over 60 years.2
- Weakened immune system. If your immune system is weakened, you may have an increased risk of small bowel cancer. E.g. HIV infection and those who take anti-rejection medicine after an organ transplant.2,3
Symptoms of small bowel cancer
Early stages of small bowel cancer can often present with no symptoms or non-specific symptoms, which can also be commonly found in other illnesses. This can make it difficult to diagnose.2,3
Most small bowel cancers are diagnosed late at more advanced stages of the disease.2,3
Symptoms may include:2,3
- Blood in stool or on the toilet paper
- Unexplained weight loss
- A lump in the abdomen
- Pain, cramps or swelling in the middle of the abdomen
- Nausea and vomiting
- Change in bowel habit including diarrhoea, constipation, or the feeling of incomplete emptying
- Tiredness and weakness, caused by a low red blood cell count (anaemia)
- Yellowing of the skin and eyes (jaundice).
If you experience any of these symptoms or have concerns, please contact your general practitioner (GP).
Diagnosing your small bowel cancer
Chapter 2
Diagnosing your small bowel cancer
Your doctor will discuss your specific symptoms with you.
There are many different types of diagnostic imaging and pathology tests used to accurately diagnose and stage small bowel cancer. The purpose of these tests is to identify the type of cancer you have and to identify the size or stage of your cancer.2,3
Blood tests – to check if there are any signs that you are losing blood in your stools, and to check for red blood cell count (low red cell count is common in people with colorectal cancer).
Capsule endoscopy – you will be asked to swallow a capsule that takes pictures of your digestive tract. These are then transmitted to a recorder you wear around your waist. The capsule is passed out in your stools, within about 24 hours.
CT scan – takes three-dimensional pictures of several organs at the same time, and can help doctors plan surgery, if required. It can also see if the cancer has spread.
MRI scan – produces detailed cross-sectional pictures of the body and can show the extent of any tumours.
PET scan – produces three-dimensional colour images that show where any cancers are in the body.
Biopsy – if your doctor sees anything unusual or abnormal, they may remove a small sample for closer examination
Barium X-ray – you ill be given a chalky barium liquid to drink which coats the inside of the bowel and can show any signs of abnormality when and X-ray is taken.
Treatments
Chapter 3
Treatments
Treatment for small bowel cancer will depend on the location and extent of the cancer, whether the cancer can be removed with surgery, likely side effects of treatment and your overall health. Your doctors will discuss the treatment options with you. They may include:2,3
- Surgery
- Chemotherapy
- Radiation therapy
- Immunotherapies
Radiation therapy for small bowel cancer
Radiation destroys lesions and tumours in a targeted site in your body. Treatment is carefully planned, and with the developments in technology, very little harm is done to normal body tissue surrounding the tumour.4
You may have internal radiation therapy (brachytherapy) or external radiation, beamed from outside the body.
At GenesisCare you are getting the latest-generation SBRT technology, including systems to improve image-guided radiation therapy, and surface-guided radiation therapy technologies.
Stereotactic body radiation therapy (SBRT) is an advanced, high precision radiation therapy technique that delivers ablative radiation doses while minimising the dose to normal tissues.4
Radiation therapy can be delivered independently or alongside chemotherapy, targeted therapies, or surgery. Your doctor will discuss your specific treatment plan with you.
Chemotherapy for small bowel cancer
Chemotherapy is medication that treats your cancer by disrupting the cell cycle. The drugs kill cancer cells, preventing them from dividing and spreading further.
Your treatment with GenesisCare
Chapter 4
Your treatment with GenesisCare
A cancer diagnosis is life changing. Even before your initial encounter with us you will experience a wave of emotions. It’s natural to feel disbelief, anxiety, sadness, anger, and loneliness. At GenesisCare we understand these emotions and strive to strengthen your confidence, settle your emotions, and create care experiences for the best possible outcomes.
Our care team know your name and get to know who you are as a person. We don’t want you to feel alone when you’re at GenesisCare. Your nursing team and oncology team are here to support you before, during and after your cancer treatment. We are here to guide you to get the support you need which may include a psychologist, exercise physiologist, physiotherapist, and dietitian.
Please contact your local GenesisCare centre for more details on services available. View a list of our centres here.
Side effects
Chapter 5
Side effects
Radiation therapy
General side effects:5
- Headache and/or dizziness immediately following the treatment
- Soreness and swelling around the treatment area
- Tiredness and lethargy for a few weeks after you finish treatment.
Specific side effects (depending on the area being treated):
- Digestive issues – reduced appetite, pain, discomfort, or bloating
- Change in bowel habits
- Raised temperature
- Nausea or vomiting.
Most of these side effects will ease shortly after treatment is finished. Your team will discuss any long-term considerations with you depending on the tumour type.
Chemotherapy
Side effects6
Whether you experience side effects and how severe they are, depends on the type and dose of drugs you are given and your reaction from one treatment cycle to the next.
- Most side-effects are short-term and can be managed.
- They tend to gradually improve once treatment stops and the normal, healthy cells recover.
You may worry about the side effects of chemotherapy. If you feel upset or anxious about how long treatment is taking or the impact of side effects, let your doctor or nurse know.
What can I do to help my treatment go smoothly?
- Get as much rest as possible
- Eat a wholefood, varied diet
- Appetite changes are common, and you may experience taste changes or nausea – help manage this by eating small, frequent snacks, avoiding smells that make you feel nauseous, eating foods that interest you rather than what you think you ‘should’ eat
- Keep up your water intake
- Reach out to support groups and others who have had
- Ask your team about topical treatments for skin if you are getting irritation or pain
- Stay out of the sun as much as possible throughout your treatment
- Record your side effects in a diary or journal
- Take some gentle exercise, such as walking, if you feel up to it. Light to moderate exercise can reduce treatment-related fatigue and improve mood.
- It is important to acknowledge when you are fatigued, and rest when you need to. Plan your exercise for times in the day when you know you have more energy
- Ask for, and accept, help from family, friends and neighbours
- Be open with employers about your treatment and discuss flexible working options where need.
Helpful services
Chapter 6
Helpful services
Other bowel cancer information, resources and support services are available to assist you during your cancer journey. These include:
Cancer Council
T: 13 11 20
cancer.org.au
GI Cancer Institute
T: 1300 666769
gicancer.org.au
Australian Cancer Research Foundation
T: 02 9223 7833
acrf.com.au
References
- Australian Government. AIHW. Cancer in Australia. 2019. Available at: aihw.gov.au/getmedia/8c9fcf52-0055-41a0-96d9-f81b0feb98cf/aihw-can-123.pdf.aspx?inline=true. Accessed on: 29/09/21.
- Cancer Council. Small bowel cancer. Available at: cancer.org.au/cancer-information/types-of-cancer/rare-cancers/small-bowel-cancer. Accessed on: 29/09/21.
- GI Cancer Institute. Small bowel cancer. Available at: org.au/cancer/small-bowel-cancer/. Accessed on: 29/09/21.
- Li D, et al. Cancer Biol Med2014; 11(4):217-236.
- Cancer Council Australia. Radiation therapy. Available at: https://www.cancer.org.au/cancer-information/treatment/radiation-therapy. Accessed on: 29/09/21.
- Cancer Council Victoria. Chemotherapy side effects. Available at: https://www.cancervic.org.au/cancer-information/treatments/treatments-types/chemotherapy/side_effects_of_chemotherapy.html. Accessed on: 29/09/21.
Disclaimer
Any procedure including treatments involving radiation carry risks, including skin irritation and associated pain. Before proceeding with a referral for treatment, patients should be advised to seek a second opinion from an appropriately qualified health practitioner. As in any medical procedure, patient experiences and outcomes will vary.
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