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Managing side effects of treatment

Stomach and oesophageal cancers and their treatment can cause many side effects. Some of these side effects are permanent and may affect your ability to eat, digest foods and absorb essential nutrients. This page explains common side effects and how to manage them.

During and after treatment, it’s important to make sure you are eating and drinking enough to maintain your weight and avoid malnutrition or dehydration. If you are eating less than usual it is often recommended that you choose high energy, high protein foods and relax healthy eating guidelines. You may need a feeding tube during or after treatment if you are unable to eat and drink enough to meet your nutritional needs. Ask your doctor for a referral to a dietitian with experience in cancer care.

After treatment, some foods you used to eat may cause digestive problems. You will need to try different foods and ways of eating to find out what works for you. You may need to change your eating habits, such as eating smaller meals more often throughout the day.

Some people find it difficult to cope emotionally with the changes to how and what they can eat. You may feel self-conscious or worry about eating in public or with friends. These reactions are natural. It may help to talk about how you feel with your family and friends, or to speak with a counsellor or someone who has been through a similar experience. They may be able to give you advice on how to adjust. It may take time and support to adapt to your new way of eating.

After surgery, you may have a poor appetite caused by changes to your digestive system. Your stomach will be smaller (or completely removed) and you will feel full more quickly. You may not feel like eating or you may have lost your sense of taste. It is important to maintain your weight. Even a small drop in your weight (e.g. 3–4 kg), particularly over a short period of time, may put you at risk of malnutrition and affect your recovery.

Chemotherapy and radiation therapy can also affect your appetite, due to nausea, irritation to the oesophagus or a sore mouth. If your oesophagus is very sore from radiation therapy, talk to your doctor about pain-relieving medicines and a referral to a dietitian.

How to prevent unplanned weight loss

  • Snack during the day – eat 5–6 small meals rather than three large ones each day.
  • Keep a selection of snacks handy, e.g. in your bag or car.
  • Make the most of the times you feel hungry or crave certain foods. Eat slowly and stop and rest when you are full.
  • Ensure you have room for nourishing food – avoid filling up on liquids at mealtimes, unless it’s a hearty soup.
  • Prevent dehydration by drinking between meals (30– 60 minutes before or after meals).
  • Test your ability to eat different foods. Your taste and tolerance for some foods may change.
  • Ask your dietitian how you can increase your energy and protein intake.
  • Don’t eat late at night. It may make you uncomfortable, bring on reflux and disturb your sleep.

You may have difficulty swallowing (dysphagia) before, during or after treatment. This may be because of where the tumour is located or a side effect of treatment. Signs that swallowing is difficult include taking longer to chew and swallow, coughing or choking while eating or drinking, or food sticking in your mouth or throat like a ball. Some people find that food and fluid goes into the windpipe instead of the food pipe. This is called aspiration and it can block the airways and cause difficulty breathing.

It is important to change your diet so that you can still get enough nutrition, and to prevent losing weight and strength. A speech pathologist can give you strategies to help you eat and drink safely.

How to manage swallowing difficulties

  • Change the consistency of your food by chopping, mincing or pureeing.
  • Make food softer, e.g. mash your food or use a slow cooker to keep food moist.
  • Snack on soft foods between meals, such as avocado, yoghurt, ice-cream, diced tinned fruit and milkshakes.
  • Chew carefully and slowly, sitting still and upright. Try to avoid talking while eating.
  • Avoid dry foods – add extra gravy or sauce to your meals.
  • Wash food down with small sips of fluid.
  • Talk to your doctor or dietitian if you are losing weight, or if you have pain or discomfort when swallowing.
  • Think about adding nutritional supplement drinks to your diet to help maintain your strength. Examples include Sustagen, Resource and Ensure.

Many people experience reflux after surgery for oesophageal cancer. This can cause heartburn, chest discomfort, or your stomach contents to flow up your oesophagus, particularly when lying flat or bending over. Taking medicines to reduce stomach acid generally helps. It is important to avoid eating or drinking before going to bed at night.

After surgery or radiation therapy for oesophageal cancer, scar tissue may cause choking or swallowing problems while eating or drinking. See your doctor if this continues. After an oesophagectomy, the stomach can take longer to empty. You may feel full more quickly or be more likely to vomit after eating.

How to relieve reflux and choking

  • Limit spicy foods, fatty foods, fizzy drinks, alcohol and citrus fruits to prevent reflux.
  • Take small sips of liquid to reduce coughing or choking.
  • Chew foods well, eat slowly, and avoid talking while eating.
  • To help food digest, sit up straight when eating and for at least another 30 minutes.
  • Consider eating your main meal earlier in the day and having a small snack in the evening.
  • After an oesophagectomy, you should remain upright for four hours after eating. Eat your evening meal more than four hours before going to bed.
  • Avoid bending over too far.
  • Keep your chest higher than your stomach when sleeping by lifting the head end of your bed with blocks about the thickness of a house brick. The whole bed should be tilted slightly.
  • Don’t overexert yourself, as this can cause reflux.

If surgery has changed the normal structure of your stomach, partially digested food and/or fluid containing high amounts of simple sugar, such as cordial, can go into the small bowel too quickly. This may cause cramps, nausea, racing heart, sweating, bloating, diarrhoea or dizziness. This is called dumping syndrome. Symptoms usually begin 15–30 minutes after eating.

Sometimes symptoms occur 1–2 hours after a meal. These are called late symptoms, which tend to cause weakness, light-headedness and sweating, and are usually worse after eating foods high in sugar.

How to manage dumping syndrome

  • Eat small meals throughout the day.
  • Chew your food well.
  • Eat slowly so your body can sense when it is full.
  • Surgery may have affected your ability to tolerate certain foods. Keep a record of foods that cause problems and talk to a dietitian for help changing your meals to reduce the symptoms.
  • Avoid eating highly processed food and eat plenty of fresh, unprocessed food.
  • Avoid foods and drinks high in sugar, e.g. cordial, soft drinks, cakes and biscuits, as eating large amounts of these foods can lead to diarrhoea and pain.
  • Eat meals high in protein, e.g. lean meats and poultry, fish, eggs, milk, yoghurt, nuts, seeds, and legumes/beans.
  • Eat starchy food, e.g. pasta, rice or potato.
  • Drink liquids between meals rather than at mealtimes.

Symptoms usually improve over time. If they don’t, ask your doctor for advice about medicines that may help.

Surgery to the stomach may reduce your ability to absorb some vitamins and minerals from food. This may lead to low levels of:

  • calcium – Over time, your bones may become weak and brittle, and break more easily (osteoporosis), which may cause pain. Talk to your doctor and dietitian about ways to look out for and treat osteoporosis.
  • vitamin B12 – This can cause a condition called pernicious anaemia. The most common early symptom of anaemia is tiredness. Your skin will look pale and you may feel breathless, get headaches, have a racing heart and lose your appetite. You will need regular vitamin B12 injections.
  • iron – This can cause iron deficiency anaemia. You may need iron supplements, which are usually given as a tablet or liquid you swallow.

Tips for managing anaemia

  • Talk to your doctor if you have symptoms of anaemia.
  • Find out what kind of anaemia you have and how to treat it.
  • Rest when you need to and don’t overexert yourself.
  • Limit tea and coffee, as these can prevent iron absorption.
  • Ask your GP or dietitian if you need iron or other supplements, and whether certain foods can help.
  • Eat foods rich in iron, such as meat, eggs and softened dark green leafy vegetables.
  • Eat foods high in vitamin C (e.g. red or orange fruits and vegetables) in the same meal as iron-rich foods. Vitamin C helps the body absorb iron.
  • If you smoke, talk to your GP about quitting or call the Quitline on 13 7848 for support and information. Tobacco can worsen your symptoms.

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This information is reviewed by

This information was last reviewed October 2019 by the following expert content reviewers: Prof David Watson, Senior Consultant Surgeon, Oesophago-gastric Surgery Unit, Flinders Medical Centre, and Matthew Flinders Distinguished Professor of Surgery, Flinders University, SA; Kate Barber, 13 11 20 Consultant, Cancer Council Victoria; Katie Benton, Advanced Dietitian, Cancer Care, Sunshine Coast Hospital and Health Service, QLD; Alana Fitzgibbon, Clinical Nurse Consultant, Gastrointestinal Cancers, Royal Hobart Hospital, TAS; Christine Froude, Consumer; Dr Andrew Oar, Radiation Oncologist, Icon Cancer Centre, Gold Coast University Hospital, QLD; Dr Spiro Raftopoulos, Interventional Endoscopist and Consultant Gastroenterologist, Sir Charles Gairdner Hospital, WA; Grant Wilson, Consumer; Prof Desmond Yip, Clinical Director, Department of Medical Oncology, The Canberra Hospital, ACT.