What types of cancer are there?
There are more than a hundred different types of cancer. Each one has its own causes and symptoms and requires its own unique treatment. The cancer is usually named after the body part where it originated, such as breast cancer. In South Africa, the National Cancer Registry (NCR) – which is kept by the National Health Laboratory Service (LHLS) – has collected information on cancer diagnoses since 1986. The 2000–2001 NCR Report indicates that prostate cancer is the most commonly diagnosed cancer amongst males, followed by lung, oesophagus, colon/rectum and bladder cancers. In women, breast cancer is the most prominent, followed by cancers of the cervix, uterus, colon/rectum and oesophagus.
What is Brachytherapy?
Brachytherapy places the radiation source as close as possible to the cancer cells, thus treatment is given over a short distance. Instead of using a large radiation machine, the radioactive material – sealed in a thin wire, catheter, or tube (implant) – is placed directly into the affected tissue. This method of treatment concentrates the radiation on the cancer cells and lessens radiation damage to some of the normal tissues (organs at risk) near the cancer. In remote brachytherapy, a computer sends the radioactive source through a tube to a catheter that has been placed at the required site by the patient’s doctor. The brachytherapy team watches the patient on closed-circuit television and directs the procedure. The radioactivity remains at the treatment site for only a few minutes. In some cases, several remote treatments may be required and the catheter may stay in place between treatments. Because no radioactive material is left in the body, the patient can return home after the treatment. For prostate cancer, the radioactive seeds implanted into the prostate stay in permanently. The patient goes home the following day because of the properties of these radioactive seeds (very low in activity and energy). Remote brachytherapy has been used to treat cancers of the cervix, breast, lung, pancreas, prostate and oesophagus. The side effects of remote brachytherapy depend on the area being treated. You are not likely to have severe pain or feel ill during or after this procedure. A Bebic Gynae Source high dose rate brachytherapy unit and 3D planning is available at our Rondebosch and Port Elizabeth units for the internal treatment of gynaecological cancers. Cancercare is one of the leaders in the field of prostate brachytherapy and has been involved with this procedure since 2003.
What equipment is used in radiotheraphy (radiation therapy)?
Equra Health is the provider of Cancercare’s radiation therapy equipment. Cancercare therefore has access to state-of-the-art digital linear accelerators which are dual energy (photons and electrons) treatment units, giving maximum flexibility in optimal treatment delivery. It generates both low (6MV) and high-energy (15MV) photon beams and a range of electron energies (4 to 18MeV), enabling the delivery of optimal doses of radiation to both superficial and deeper-seated tumours. Multi leaf collimators allow for the delivery of complex shaped 3D and IMRT treatment plans. Cone beam CT and Electronic Portal Imaging provide for fast image acquisition for verification. Due to the highly specialised nature of these treatment machines, routine structured equipment maintenance and replacement is done by in-house service engineers. This, together with routine quality control procedures, ensures that the equipment is in top condition. Cancercare’s record and verify systems are sophisticated computer software programmes used to record all treatments and check the correct set-up of the treatment units prior to each treatment. It ensures patients’ peace of mind as it prohibits treatment unless all set-parameters are correct. Treatment Planning Systems (CMS XiO) are used for 3D treatment planning and inverse planning for IMRT. These planning systems are linked to CT, MRI and PET imaging facilities to provide for accurate delineation of tumour volumes through the highest quality diagnostic imaging available. Cancercare has a well-established centralised planning centre in Cape Town which ensures that throughout the organisation, the highest quality and standard of planning based on international standards is achieved for all patients. Highly specialised stereotactic radiosurgery and radiotherapy is offered at our Rondebosch branch, where the Brainlab planning software is used for the treatment plans. A frameless mask system is used to deliver high doses of radiation to small cranial lesions on the linear accelerator.
What happens in the treatment process?
The treatment process involves: A highly-qualified radiation therapist delivers the daily radiation treatment using specialised treatment machines called linear accelerators. The treatment is delivered as prescribed from Monday to Friday and can range from one to 37 treatments, depending on the site and stage of the disease. Computerised record and verify systems are part of the stringent quality assurance systems used in treatment delivery, and ensure that all treatment parameters are met before the beam is switched on. It also keeps a daily record of all treatment delivered for each patient. The routine use of Electronic Portal Imaging allows visual and digital verification of the treatment area. Images are taken in the treatment position prior to the start of treatment and weekly thereafter as part of the quality control procedures. This ensures compliance to the treatment plan and allows for the correction of any treatment variations which may occur due to internal or external movement between treatments. Dose verification is done by means of in-vivo dosimetry at the start of treatment to ensure that the planned dose is delivered for each patient. This is done by placing a small monitor on the centre of the beam to measure the dose output of the linear accelerator. Doses to sensitive structures such as eyes can also be measured in this manner.
What does the planning process for treatment involve?
When radiation treatment is prescribed, the area of interest is usually determined by doing a planning CT scan. This is different from a diagnostic CT scan as it is done in the treatment position. Special immobilisation devices are used to ensure accurate daily set up in the same position. Other imaging modalities such as MRI and PET-CT scans can be done in certain cases, and matched/fused with the planning CT scan, to aid delineation of the tumour volume. Once the planning scans have been done, the tumour volume is delineated by the oncologist and surrounding normal tissue by the radiation therapist. This is done on a specialised treatment planning system capable of planning 3D conformal radiation therapy as well as highly specialised intensity modulated radiation therapy (IMRT). All treatment plans are done with the input of the radiation oncologists, radiation therapists and medical radiation physicists to ensure that the highest quality plan is achieved as prescribed. All planning is done in accordance with international prescribing norms and standards.
What is volumetric modulated arc therapy (VMAT)?
Volumetric modulated arc therapy (VMAT) is an advanced radiation technique determined as a treatment option by your oncologist depending on the size, location and type of the tumour. VMAT can achieve highly conformal dose distributions on tumour volume coverage while sparing normal tissues. Should you have this form of treatment, you will notice that the head of the machine (called the gantry) rotates around you. During treatment, the gantry speed and beam intensity also change. VMAT has the added advantage of reduced delivery/treatment time of radiation compared to conventional intensity modulated radiation therapy (IMRT).
What is intensity modulated radiation therapy (IMRT)?
Intensity modulated radiation therapy is an advanced way of delivering the radiation dose to the tumour with different intensity levels. This treatment option is determined by your oncologist depending on the size, location and type of tumour. Some tumours wrap around sensitive structures – for example, the spinal cord – and to administer an adequate dose to the tumour can be very difficult. This technique however, can control the intensity of the radiation beam by using multiple fields coming from different directions. In certain cases, IMRT also allows radiation doses to challenging areas that need re-treatment. Treatment planning is done by using 3D computed tomography (CT) and/or magnetic resonance images (MRI).
What is stereotactic body radiation therapy (SBRT)?
The principles of cranial SRS – where delivery is accurate to within one to two millimetres – are now being applied to the treatment of body tumours with a procedure known as stereotactic body radiation therapy (SBRT). This procedure is also available at some of our practices. SBRT is used in the body and common disease sites include the lungs, liver, abdomen and spine. SRS and SBRT are usually performed on an outpatient basis. The immobilisation, imaging and planning process is very different to the conventional planning process. SRS and SBRT are important alternatives to invasive surgery, especially for patients who are unable to undergo surgery, as well as for tumours and abnormalities in challenging positions – those located close to vital organs/anatomic regions, or those subject to movement within the body. 4D CT scanning (gated) is used to assist with this movement in the body.
Can I recover from cancer?
Brachytherapy places the radiation source as close as possible to the cancer cells, thus treatment is given over a short distance. Instead of using a large radiation machine, the radioactive material – sealed in a thin wire, catheter, or tube (implant) – is placed directly into the affected tissue. This method of treatment concentrates the radiation on the cancer cells and lessens radiation damage to some of the normal tissues (organs at risk) near the cancer. In remote brachytherapy, a computer sends the radioactive source through a tube to a catheter that has been placed at the required site by the patient’s doctor. The brachytherapy team watches the patient on closed-circuit television and directs the procedure. The radioactivity remains at the treatment site for only a few minutes. In some cases, several remote treatments may be required and the catheter may stay in place between treatments. Because no radioactive material is left in the body, the patient can return home after the treatment. For prostate cancer, the radioactive seeds implanted into the prostate stay in permanently. The patient goes home the following day because of the properties of these radioactive seeds (very low in activity and energy). Remote brachytherapy has been used to treat cancers of the cervix, breast, lung, pancreas, prostate and oesophagus. The side effects of remote brachytherapy depend on the area being treated. You are not likely to have severe pain or feel ill during or after this procedure. A Bebic Gynae Source high dose rate brachytherapy unit and 3D planning is available at our Rondebosch and Port Elizabeth units for the internal treatment of gynaecological cancers. Cancercare is one of the leaders in the field of prostate brachytherapy and has been involved with this procedure since 2003.
What is stereotactic radiosurgery (SRS)?
Stereotactic radiosurgery (SRS) is a non-surgical procedure. It was initially developed to treat small brain tumours and functional abnormalities of the brain. SRS is a highly precise form of radiation therapy using the linear accelerator. With this treatment, precisely-targeted radiation can be delivered at much higher doses while minimising the dose to the surrounding healthy tissue. This can be achieved in a single treatment or over a few treatments. The radiation oncologist determines the choice of the fractionation scheme. This treatment is only indicated for certain benign and malignant tumours depending on the size, number, site and type of tumours.
What is Cancer?
Cancer is a disease where some of the body’s cells begin to divide without stopping and spread into surrounding tissues. Our bodies are made up of trillions of cells. Normally, human cells grow and divide to form new cells as the body needs them. When cells grow old or become damaged, they die and new cells take their place. When cancer develops, however, this orderly process breaks down. As cells become more and more abnormal, old or damaged cells survive when they should die, and new cells form when they are not needed. These extra cells can divide without stopping and may form growths, called tumours. Many cancers form solid tumours, which are masses of tissue. Cancers of the blood, such as leukaemias, generally do not form solid tumours. Cancer can affect men, women and children, young and old, rich and poor. You cannot catch cancer from someone else, nor give it to others. With new methods of treatment eminent, many people recover from cancer.
Can children get cancer?
According to Cansa, between 800 and 1 000 South African children under the age of 15 are diagnosed with cancer each year. If detected early, most children can be treated successfully. Children with cancer need to receive the right treatment and preferably this should be done in a pediatric oncology unit.
Warning signs for childhood cancer:
- Continued, unexplained weight loss
- Headaches with vomiting in the morning
- Increased swelling or persistent pain in bones or joints, sometimes accompanied by limping
- Lump or mass in abdomen, neck, or elsewhere
- Development of a whitish appearance in the pupil of the eye or sudden changes in vision
- Recurrent fevers not caused by infections
- Excessive bruising or bleeding (often sudden)
- Noticeable paleness or prolonged tiredness
How do I know if I may have cancer?
Although some cancer-related symptoms may be caused by another health problem, it is important to remember that should one or more of these symptoms persist, you have to consult your doctor immediately. Warning signs for adult cancer:
- change in a wart or a mole
- any continued fever
- nagging cough or continued hoarseness
- chronic pain in bones or any other area of the body
- enduring fatigue, nausea or vomiting
- repeated infection and/or inflammation
- change in bowel or bladder habits (pain, difficulty urinating, blood)
- a sore that does not heal
- unusual discharge or abnormal bleeding
- thickening or lump in the breast, testicles or elsewhere
- indigestion or difficulty in swallowing
- obvious change in the size, colour, shape or thickness of a wart, mole or mouth sore
- noticeable weight loss and loss of appetite
What is external beam radiation therapy?
A linear accelerator machine is used to deliver external beam radiation therapy. This machine can generate high energy x-rays or electrons outside the body which are then targeted at the tumour site. The ionising radiation is deposited into the body to kill malignant cells.
How does radiation therapy work?
Radiation therapy is one of the most common cancer treatments and can be prescribed for a range of different diagnoses. Although targeted at abnormal cells, radiation also affects normal cells, but they can recover more quickly than the abnormal ones. Generally, treatment is given five (5) times a week to allow normal cells to recover over the weekend, though treatment does not need to start on a Monday and therefore does not necessarily need to be consecutive. Treatment intent can be either curative or palliative. Curative treatment aims to eradicate the cancer completely whereas palliative treatment aims to improve quality of life by treating the symptoms by decreasing tumour bulk. The radiation oncologist decides on treatment intent. It is likely you will meet other patients during the course of your treatment who compare your treatment and diagnoses to theirs. It is important to keep in mind that your treatment was designed specifically for you and may be completely different to theirs. Not everyone will experience the same symptoms or side effects of treatment. Radiation therapy may be administered alone, or in combination with chemotherapy or surgery as part of a multidisciplinary approach. Some chemotherapy drugs are administered as a radiation therapy sensitiser to make cancer cells more responsive to radiation. Radiation therapy includes different ways of administration which may be used in combination for a single patient. Cancercare’s practices apply the following treatment techniques
- external beam radiation therapy
- stereotactic radiosurgery (SRS)
- stereotactic body radiation therapy (SBRT)
- intensity modulated radiation therapy (IMRT)
- volumetric modulated arc therapy (VMAT)
- brachytherapy
Some specialised techniques are only available at certain practices.
Why is cell division important to understand?
Before understanding how radiation therapy works, it is important to understand the normal mechanism of cell division. Normal cells reproduce and differentiate in an extremely controlled manner. Cells begin to grow abnormally when this process is disturbed and becomes uncontrolled. Abnormal growth continues in an uncontrolled and disorganised manner until cells infiltrate and damage surrounding tissues.
What is radiation therapy?
Radiation therapy is a therapeutic treatment that uses ionising radiation to eradicate or damage cancer cells. High energy x-rays or electron beams of varying energies are used in accordance with the doctor’s prescription.
How are cancer drugs administered?
Drugs are given in different ways. The four most common methods are
- intravenous (IV)
- by mouth
- intramuscular and
- intrathecal
The chosen method of administration is based on diagnosis and the drug`s characteristics. Some medications are taken by mouth in the form of a pill, capsule or liquid. The term intramuscular means that the drug is injected into the muscle, usually in the arm, thigh or buttock. Some drugs may be injected into the tissue under the skin rather than into the muscle. This is referred to as a subcutaneous injection. Giving medicine intravenously or directly into a vein is a very common method. Medication flows from a plastic bag, through tubing, into the bloodstream. Sometimes a syringe is used to push the drugs through the tubing. Certain types of leukaemia and lymphoma tend to spread to the nervous system. To prevent or to treat this, a physician may perform a spinal tap and inject chemotherapy into the spinal fluid to destroy cancer cells. This is known as intrathecal delivery.
How are cancer drugs administered?
Drugs are given in different ways. The four most common methods are
- intravenous (IV)
- by mouth
- intramuscular and
- intrathecal
The chosen method of administration is based on diagnosis and the drug`s characteristics. Some medications are taken by mouth in the form of a pill, capsule or liquid. The term intramuscular means that the drug is injected into the muscle, usually in the arm, thigh or buttock. Some drugs may be injected into the tissue under the skin rather than into the muscle. This is referred to as a subcutaneous injection. Giving medicine intravenously or directly into a vein is a very common method. Medication flows from a plastic bag, through tubing, into the bloodstream. Sometimes a syringe is used to push the drugs through the tubing. Certain types of leukaemia and lymphoma tend to spread to the nervous system. To prevent or to treat this, a physician may perform a spinal tap and inject chemotherapy into the spinal fluid to destroy cancer cells. This is known as intrathecal delivery.
When is chemotherapy used as a treatment?
In definitive therapy when the best chance of cure is with chemotherapy. In neo–adjuvant therapy prior to surgery or radiation to reduce tumour burden prior to definitive therapy with either modality. In combination therapy with radiotherapy, either sequentially or concurrently, to enhance the effects of radiation (chemo radiation). In secondary therapy to try to cure metastatic disease. In palliative therapy to improve specific symptoms and enhance the quality of life.
What is the goal of chemotherapy?
To destroy cancer cells. To shrink a tumour before other treatments. To destroy cancer cells after other treatments. To enhance the sensitivity of cells to radiation
What is chemotherapy?
Chemotherapy is the treatment of cancer with chemical drugs that are designed to destroy cancer cells. Although such treatment potentially also affects normal cells; these have the ability to repair themselves, whilst damage to cancer cells is usually of a more permanent nature. Combination chemotherapy forms the basis of most chemotherapy treatment. The goal is for different drugs to be used that complement each other in their destructive effects on cancer cells whilst reducing side effects and toxic effects on normal cells. The combination of drugs also reduces the chance of cancer becoming resistant to the treatment. This can be achieved because of their different mechanisms of action and side effect profiles.
How is cancer treated using surgery?
A cancer tumour that has not spread can be removed. This is done by a surgeon during an operation. The tumour – and sometimes some more tissue – is taken out. Sometimes it is followed by chemotherapy and/ or radiation therapy (see below). Not all cancers can be removed in this way; sometimes the doctors use medicines like chemotherapy to shrink and control the cancer. A multidisciplinary team works together to determine which treatment you need. This team consists of a surgeon, radiation oncologist and medical oncologist – as well as radiation therapists and nurses. Your diagnoses and general health conditions will determine your treatment. Feel free to ask any questions throughout your treatment process. The therapy team is especially trained to assist you in any way possible, and this includes referring you to counsellors, dieticians and social workers.
How is cancer treated using surgery?
A cancer tumour that has not spread can be removed. This is done by a surgeon during an operation. The tumour – and sometimes some more tissue – is taken out. Sometimes it is followed by chemotherapy and/ or radiation therapy (see below). Not all cancers can be removed in this way; sometimes the doctors use medicines like chemotherapy to shrink and control the cancer. A multidisciplinary team works together to determine which treatment you need. This team consists of a surgeon, radiation oncologist and medical oncologist – as well as radiation therapists and nurses. Your diagnoses and general health conditions will determine your treatment. Feel free to ask any questions throughout your treatment process. The therapy team is especially trained to assist you in any way possible, and this includes referring you to counsellors, dieticians and social workers.
What treatments are there for cancer?
The most common treatments for cancer are surgery, chemotherapy, radiation therapy and brachytherapy. These may be applied on their own or in combination with one other.
What are the risk factors for cancer?
- smoking cigarettes or using tobacco products like snuff, pipe or chewing tobacco.
- having been sunburned often
- some viruses: HIV, HPV and Hepatitis B virus
- unhealthy lifestyle: being overweight, limited physical exercise, too much alcohol, too many sugars and too much red meat, not enough vegetables and fruit
- genetic: a family history of cancer (some of your close relatives – father, mother, brothers or sisters – have had breast, bowel, melanoma or ovarian cancers)
- pollution and toxins in the environment (dirty air and water, smoke and chemicals that we breathe)
How does the doctor determine if I have cancer?
First the doctor [your general practitioner] will listen to your story and do a physical examination. Should he/she find something, there are several ways to find out if it is cancer or not, namely:
- Biopsy. A small piece of the tumour is cut out and looked at under a microscope to determine the type of cancer.
- Endoscopy. This is a medical procedure where a doctor puts a tube-like instrument into the body to look inside. There are many types of endoscopy, each of which is designed for looking at a certain part of the body e.g. gastroscopy for the stomach and cystoscopy for the bladder.
- CT scan or MRI scan. The machine takes many pictures (x-rays) of the body taken from different angles. These are then combined to give a detailed picture of internal organs. Doctors are then able to look for tumours. The CT and MRI scans are painless.
- Mammogram. This is a special type of low dose x-ray used to detect breast cancer. The breast is compressed (squeezed by a machine) during the procedure and so it may be slightly uncomfortable.
- Bloods. Sometimes cancer cells give off substances that can be detected in the blood. This tells the doctor that there is cancer somewhere in the body. They are called blood markers.