Research – clinical trials
Research into new ways of treating bone cancer is going on all the time. When a new treatment is being developed, it goes through various stages of research. To begin with it will be looked at in the laboratory, and sometimes tested on cancer cells in a test tube. If the treatment seems as though it might be useful in treating cancer, it is then given to patients in research studies (clinical trials). As a first step, these aim to find a safe dose, see what side effects the therapy may cause, and decide which cancers it might be used to treat. These early studies are known as phase 1 trials.
CancerBACUP can give you information about current trials and can advise you how to contact the appropriate organisation or doctor.
If these early studies suggest that the new treatment may be both safe and effective, further trials are done to find out whether it is better than existing treatments, or has extra benefit when given together with these treatments. These trials (phases 2 and 3) compare the new treatment to the current best standard treatments.
So clinical trials are very necessary to work out how useful any possible new treatment might be, and whether it could be better than existing treatments. Because this must be done carefully and thoroughly, it usually means that it takes some years from the time when a new treatment is first discovered (often with a lot of publicity in the papers and on TV) until the time when its true value is established.
You may be asked to take part in a trial. There can be many benefits to doing so. You will be helping to improve knowledge about cancer and the development of new treatments and you will be carefully monitored during and after the study.
As bone cancers are very rare, trials are usually organised by specialists from many countries working together and may take years to complete. Clinical trials for osteosarcoma and Ewing’s sarcoma are especially important so that more people can be cured. Currently there is a trial called EURAMOS1 for osteosarcoma. The Euro-Ewing 99 trial is for Ewing’s sarcoma.
CancerBACUP has a section on clinical trials, which explains clinical trials in more detail.
I am going to have a course of radiotherapy to treat my cancer. The doctors took a blood test today and when I asked about this they said it was important to make sure I wasn’t anaemic before I had the treatment? Why is this?
Radiotherapy uses a type of radiation, called ionising radiation, to destroy cancer cells. There are several types of ionising radiation including x-rays, gamma rays and beta rays. Most radiotherapy treatment for cancer use x-rays.
Ionising radiation works by releasing chemicals in the nucleus of cells. These chemicals, called free radicals, damage the DNA, the genetic material that is vital for the cell to multiply. If the DNA is sufficiently damaged by the radiation then it will not be able to divide and will die off.
In order for the radiotherapy to release the free radicals that damage the DNA there needs to be a good supply of oxygen in the cells. If the cells are starved of oxygen then this actually protects them against the effects of the x-rays and makes treatment less effective.
Oxygen is carried to the tissues and cells in our bodies by the haemoglobin in the red blood cells. If we are anaemic then the haemoglobin level in the blood is low, and so the amount of oxygen carried by the blood to our cells is reduced.
So in order to get the best results from a course of radiotherapy it is important to be sure that you are not very anaemic before you start treatment.
If you are anaemic then your doctors may well suggest a blood transfusion before you start your treatment. This will boost your haemoglobin level and will increase the oxygen in your blood, which will increase the chances of success from your radiotherapy treatment.
I have recently finished treatment for a cancer. My doctors have given me the all clear but how can I be sure I am cured and the cancer won’t come back?
Very often when a cancer is treated the treatment will take away all evidence of that cancer: symptoms will disappear, physical examination and special tests (like blood tests and scans) will all go back to normal. All the appearances will suggest that the problem has been cured.
But sometimes there will be microscopic traces of the cancer left behind. Because they are so tiny these traces will not cause any symptoms and they will be too small to show up on even the most careful of examinations and most sensitive of special tests. These tiny clusters of cancer cells may lie dormant for months or years but may eventually grow and the cancer may come back.
Since these minute cells that might have been left behind cannot be detected in any way it is impossible to give an absolute guarantee that a cancer has been cured after treatment.
Having said this, very many people are cured of their cancer by modern day treatment. The chances of getting a cure depend on the type of cancer that someone has, how advanced (how large it was and how far it had spread) at the time it was first discovered (this is sometimes known as the ‘stage’ of the cancer) and how well that cancer responds to treatment.
There are now masses of statistics which doctors can use as a guide to predicting the chances of a cure for any particular cancer at any particular stage. These show that for some of the more curable types of cancer the chances of the cancer coming back after treatment are very small indeed, particularly if it was discovered at an early stage. Whereas for other types or cancers diagnosed when they were more advanced, the outcome is likely to be poorer.
These figures are only ‘statistics’ which means they cannot absolutely predict what will happen to an individual but they do give a good idea of the ‘chances’ of whether, or not, someone will be cured. So doctors rely on these figures for deciding what the likely outcome is for each person at the end of their treatment.
These days many many people are cured of their cancers. So if your doctors have given you the ‘all clear’, although there is no absolute way of proving they are right and guaranteeing you are cured, they obviously think your chances of success are excellent and you should look forward to the future with confidence.
My mother is having treatment for a cancer. The doctors have said she cannot be cured but have told her that because of treatment her condition is now stable. What does this mean?
Despite the advances that have been made in the treatment of cancer there are still many tumours that cannot be cured. In these situations it often possible for different treatments to stop the growth and spread of the cancer, or even to shrink it for a period of time.
Depending on the type of cancer and treatment which has been given this period of time when the tumour is no longer growing may last from a few weeks to a number of years.During this time the tumour is said to be under control or ‘stable’.
Other phrases which are sometimes used to describe this situation are ‘static disease’ and ‘ISQ’ (in status quo). If the cancer has shrunk by at least 50% before the period of ‘stabilisation’ this may be referred to as a ‘partial remission’ or ‘partial regression’ or ‘partial response’ (all three terms mean the same thing).
Small changes in tumour size, either recorded by direct measurement or by looking at images on x-rays or scans are difficult to assess precisely. Therefore there is general agreement among cancer specialists that in order for a cancer to show signs of progression, or a relapse, there must be a greater than 25% change in the measurements that have been used to assess it. So provided that any change is less then this level, and assuming there has been no other evidence to suggest the disease is becoming active again), then the condition will still recorded as being ‘stable’.
I have cancer and have been told I will need radiotherapy. I am so frightened that the radiotherapy will burn me. I have heard such a lot of stories about this. What can I do?
In the early days of radiotherapy treatment, skin burns during treatment and sometimes permanent damage or scarring of the skin, was common.
This changed during the late 1950s and 1960s as two new types of
machine were introduced to give the radiotherapy treatment. These are
called Linear Accelerators and Cobalt Units. These machines produce
irradiating rays of a much greater energy than the previous machines.
This higher energy of the rays give the treatments greater accuracy and
greater penetration of the tissues (allowing treatment of cancers deep
inside the body and also reduce skin damage. This is because the high
energy rays pass through the first centimetre or two of the first tissue
they meet, before they actually begin to give out any radiation.
Skin problems are uncommon with modern radiotherapy treatment. Occasionally skin problems can occur because of the location of the cancer and the area of the body treated. Usually this will cause no more than some temporary pinkness or redness of the skin for a week or two after treatment. If any soreness does develop it will only last a short time and can usually be eased with creams or lotions, which you will be given at the hospital. Severe or permanent skin damage is rare indeed.
The fact that skin damage was common forty or fifty years ago means that people can remember friends or relatives who had bad experiences with their radiotherapy treatments which probably account for the stories you have heard. Nowadays the situation is very different and things have improved enormously.
I am about to have a course of radiotherapy following an operation for cancer. If I go on holiday in a few months from now, will I be able to go out in the sun?
Radiotherapy is almost always a local treatment, limited to a particular part of the body. Only the skin in that area will be irradiated and the skin elsewhere will not be affected.
The doses of radiotherapy used can vary but even with quite high doses modern radiotherapy machines usually cause a little skin irritation. Even so this does mean that the skin which has been irradiated will be more sensitive to sunlight than your normal skin.
The degree of sensitivity will vary from person to person. The increased sensitivity also reduces gradually with time but probably never disappears completely.
Having had radiotherapy does not mean you must avoid the sun completely but you should take care over exposing the treated skin. It is very important to cover the treated area for at least the first year after radiotherapy. Wear clothing made of cotton or natural fibres which have a closer weave and offer more protection against the sun. Even after this time the area treated will be more delicate, so extra care should be given. You should also use a high factor sunscreen (of at least factor 15). Remember, too much sunbathing does carry the risk of leading to skin cancer and should be avoided.
Very occasionally radiotherapy is given to the whole body. In this situation the doses are normally quite low but you should still take precautions in exposure to strong sunlight. Seek advice from your doctors if you are having this type of treatment.