How radiation therapy works
Effects of radiation
Radiation therapy works by directing radiation at DNA, the genetic information contained within a cell's nucleus, which controls both structure and functioning of the human body. The cells of most tissues in the human body are constantly undergoing cell divisions. Before a cell goes through this process, the DNA inside the nucleus has to be duplicated. This is necessary in order to ensure that the entire genetic code is passed to the newly developing cell.
High-energy radiation can cause changes in a cell's DNA and can thus disrupt how information is transmitted. Such disruption can cause a cell to die or it may lose the ability to undergo cell division, causing the cell to age prematurely and leading to the premature death of the tissue or tumour. Once dead, the tumour tissue is broken down by the body's own enzymes, leaving only the cell's building blocks. Naturally, the DNA of healthy cells is not immune to radiation damage. However, normally functioning cells have a number of processes at their disposal to detect and repair such damage.
While tumour cells can cell damage repairs take much longer than is the case in normal tissue. The healthy cells' ability to recover more quickly from radiation damage can be exploited during treatment by ensuring radiation therapy is delivered in small daily radiation doses, spread over a number of weeks.
Modern radiotherapy, which combines the use of powerful modern radiation equipment with computer technology, is capable of delivering high energy radiation to tumour tissue whilst minimising the radiation exposure of surrounding healthy tissue. This is achieved by firing radiation beams at the tumour from different directions, ensuring that the maximum dose is delivered at the point inside the tumour where the different beams meet.
Receiving radiotherapy - first consultation
Most patients who are referred to us have already been diagnosed as having malignant tumours, however, we do receive referrals for patients with benign disorders. In order to be able to determine whether radiation therapy is necessary in your case, you will need to bring your medical notes, detailing any previous findings. It is of particular importance that these notes include histology findings, operative reports, reports on investigations such as ultrasound or bone scans, as well as any images obtained by X-ray, CT or MRI. This will allow the doctor to get a complete picture of your illness and symptoms before making appropriate decisions regarding a treatment plan.
Your doctor will discuss with you in detail what type of radiotherapy treatment will be necessary in your case and how this treatment will be delivered. You will also have a physical examination to allow the doctor to adequately assess your general health.
You will also be told in detail about any potential side effects of the treatment and any preventative measures as well as being given advice on skin care during and after radiation therapy. At the end of your first consultation you will be given an information sheet which will outline the most important potential side effects. This is for you to take home and read at your leisure. If you agree to the treatment, please sign the form and bring this with you to your next appointment. At this next appointment, please also feel free to ask the doctor about anything that you are unsure about.
Treatment is possible on an inpatient or outpatient basis but the decision on which of these approaches is suitable in your case will depend on your general health, how far away you live and what type of treatment may be involved. For instance, in some cancers radiation is administered twice a day, with a minimum break of six hours between doses. Other disorders may require radiotherapy to be complemented by simultaneous chemotherapy. As a result, cases such as these will require a stay in hospital.
While radiation sickness used to be an unwelcome side effect of radiation therapy this only occurs nowadays in cases of treatment over very large areas, e.g. when treating cancer of the lymph nodes, or as a result of total body irradiation. Thanks to the use of high energy photon beams and multiple field radiotherapy, radiation "burns" are now a rare occurrence. Naturally, in cases of tumour infiltration of the skin or superficially placed tumours, the skin may need to be exposed to the full dose of radiation and more severe skin reactions can occur. However, with appropriate topical treatment these will usually heal within two to three weeks. Skin within the radiation field may be washed with water but soap should be avoided. Other irritants such as cold temperatures, heat treatment, deodorants and, in particular, exposure to the sun, must be avoided. Radiation-induced mucositis (inflammation of the mucous membranes) is a common side effect in the treatment of head and neck cancers. This is something that is unfortunately unavoidable as there will always be mucous membranes inside the radiation field. As a result, standard preventative measures include aggressive oral hygiene and the avoidance of additional irritants such as alcohol or nicotine. Possible inflammation of the jaw and associated tooth decay can be prevented by undergoing dental treatment prior to radiotherapy and applying intensive fluoride treatment for an extended period of time.
Before beginning radiotherapy, radiation fields must be accurately determined by a simulator, a special type of X-ray machine that emulates the movements of the radiotherapy machine. The machine rotates around a central axis, which means that images can be produced from any angle. The patient will be positioned horizontally on the scanner table and asked to find as comfortable a resting position as possible. A variety of different types of equipment are available to ensure that a comfortable position can be found and maintained, including knee cushions, arm rests and neck supports.
For head and neck radiotherapy it is also necessary to immobilise the head to ensure precise positioning. In order to achieve this, a special mask has to be made, which is moulded to the individual patient's head. To make a mask, a thin plastic mesh is mounted on a frame and heated to make it mouldable. This mouldable mesh is places over the patient's face and is moulded to the exact contours of the patient's nose, chin and forehead. It is then left to harden for between 5 and 10 minutes.
If a tumour is clearly visible on an X-ray, the radiation fields can be determined directly based on this, including the size of the area to be irradiated, the angle at which radiation beams have to be fired and the depth they have to be delivered to. The area of the radiation field is then outlined on the skin (or mask) using a marker pen and X-Rays will be taken of the tissue region that is to be irradiated. Depending on the type of disorder being treated this simulation process will take between 10 and 45 minutes. The most important way to assist this process is to try and find a position which is comfortable and which allows you to lie still.
If a tumour is not clearly visible on an X-ray or is situated too close to a radiation-sensitive organ, a CT-scan will be performed prior to the simulation procedure being carried out. For the CT-scan, the patient will need to lie in the exact position they will be required to adopt during radiation therapy treatment.
Individual CT-images can be viewed on a computer and the doctor can determine the exact location of the area to be irradiated. To achieve this, the doctor will mark the target area to be irradiated on each of the scan images and highlight any radiation-sensitive organs. A medical physicist then calculates the exact treatment depth, angle and radiation dose before a simulation is carried out exactly according to these instructions. As described above, the simulation process produces X-rays of each area to be irradiated, with the radiation field being marked on the skin (or mask). In addition, certain areas of the body will be marked to ensure that the exact positioning of the patient can be reproduced each time radiation is administered.
As most tumours are irregular in shape, heavy metal blocks are used to adjust the normally rectangular radiation field to the shape of the tumour (conformal therapy).
External beam irradiation will be performed with one of our two linear accelerators. Prior to the initial treatment session all parameters of the treatment plan will be checked by a radiologist's assistant, referred to as an MTRA ("medical technical radiology assistant"), a medical physicist and a doctor. In addition, test images for verification of the radiation field placement are taken. All this preparatory work means that the first treatment session will take longer than subsequent treatments.
You will be on your own in the treatment room, while the actual radiotherapy treatment is administered. However, via a video installed inside the treatment room the MTRA will be able to see you from the control room. In addition, the MTRA will be able to talk to you via an intercom. Irradiation usually takes between 20 and 100 seconds per radiation field. Taking into account the time for correct positioning and adjustment of radiation fields, this means that patients will have to remain on the scanner table for between 5 and 15 minutes.
After your first treatment the MTRA will let you know the dates and times of your subsequent treatments. Treatments usually take place on weekdays only. Depending on the type and severity of disease, the total number of treatments required is usually between 10 and 39.
Our modern computer-assisted verification systems allow exact data about radiation fields to be stored and overall doses to be tracked, and therefore radiotherapy errors have become extremely rare. In addition, our modern digital imaging techniques make it possible to control and adjust the radiation field during the process of irradiation. The process is comparable to the use of X-rays during simulation (Portal Imaging System).
If you feel any discomfort during your treatment, or if you have any questions, please speak to your MTRA, who will be able to refer your query to the doctor. After your final treatment you will have another meeting with your doctor who can advise you on any skin care that might be necessary as well as advising you on anything else you may need to do. We will usually want to arrange a follow-up appointment to check on your progress and to ascertain if there have been any side effects. You will also be able to discuss any further follow-up care, which will usually be carried out by the referring general or specialist practitioner.
During your final consultation appointment your doctor will give precise instructions on what you need to do over the next few weeks and the doctor may prescribe some medicines or skin care products. After this meeting you will be referred back to your general or specialist practitioner. Your general practitioner will work in close contact with us and from time to time you will be asked to return to the unit so that overall progress can be assessed. This will allow us to check how successful your treatment has been, and give us the opportunity to identify any potential side effects early and, if necessary, decide on appropriate treatment.
Your first follow-up appointment will be about three months after the end of your treatment. Further follow-up appointments will then be either every three months or every 12 months, depending on the nature of your progress. Should you have any questions regarding your illness or its treatment, please feel free to contact the doctor responsible for your follow-up care for advice at any time. If there is anything you are concerned about or if you notice anything unusual, please ask your doctor to refer you to back the radiotherapy clinic.
Some types of cancer, mostly uterine cancers but also some cancers of the oesophagus and the major bronchi, are best treated by a source of radiation from within the direct vicinity of the tumour. This is done by placing an applicator directly inside the affected organ and close to the tumour. In women who have had surgery for gynaecological cancers, vaginal brachytherapy is possible without a general anaesthetic.
Using a remote-controlled system, the source of radiation (usually Iridium-192) can be placed via guide tubes directly from a shielded safe into the applicator. A 3D treatment plan makes it possible to calculate and target exact radiation doses. In other types of cancer, e.g. prostate cancer, a general anaesthetic will be required as hollow needles need to be inserted directly inside the tumour before the radioactive source is then introduced directly into the needles.
An advantage of this therapy is the close proximity between the source of the radiation and the tumour, which leaves the surrounding tissue - even as close as 1cm away - virtually unaffected by the radiation. Consequently, high doses can be applied to the tumour and negative effects on the surrounding tissue can be minimised. However, this method is only suitable for the treatment of small volume tumours. In addition, brachytherapy often needs to be combined with external beam radiation in order to ensure targeted treatment of the tumour on the one hand, and simultaneous treatment of the surrounding lymph nodes on the other.
What is Radioiodine Therapy?
For approximately 60 years now, Radioiodine Therapy has been known as an effective treatment method with very few side-effects. This therapy method can be used in a targeted manner to treat overactive sections of the thyroid, whilst sections that function normally, are preserved.
Treatment uses the radioactive form of iodine, an element that is well-known as a naturally-occurring component of our food.
What happens during treatment?
You will be asked to take a small capsule containing radioactive iodine. The radioactive iodine will reach your bloodstream from where it will be absorbed by the overactive parts of the thyroid gland.
In over 90 % of cases, this treatment can cure an overactive thyroid. There is no need to worry about any negative effect as there are no known significant side effects.
Due to German as well as European regulations on radiation safety it will be necessary for you to remain in the hospital as an inpatient for the duration of your treatment. The reasons for this are:
- Firstly, a small amount of the total radiation received will be measurable outside the body (gamma radiation)
- Secondly, the radioactive iodine absorbed by the thyroid is later excreted via urine and faeces. All bodily wastes are collected via a special collection system and disposed of once radiation levels have reached acceptable levels.
What you need to know:
Please note that it will not be possible for you to receive visitors while you are staying with us.
All our rooms are
very pleasant and are equipped with:
- Adjustable beds
- Telephone (charges applicable)
- Washing facilities
Smoking is not allowed during your stay.
Please remember to bring things that will help make your stay more pleasant, e.g. magazines, books, a radio with headphones, laptop, and mobile telephone.
Admission to hospital
08:30 - 09:00
Please bring the following with you:
- Your referral letter
- Health insurance card
- Sour lemon sweets
- Any medicines you are currently taking and that you will need during your stay (for example heart or blood sugar medicines and, if applicable, insulin, and any devices you may need to measure your blood sugar or blood pressure).
- Nicotine patches (if applicable)
Our 21-bed Ward (ST 01), located in Building F, is available should have difficulties getting to the unit for treatment, either because you live too far away, because you are in too much pain or because you have been told to observe strict bed rest. The Ward is also always available to you when you are not in active radiotherapy treatment, e.g. when you are in pain or when you have unexplained symptoms that need to be assessed. We also have patients staying with us who are receiving chemotherapy treatment. Usually, chemotherapy is administered as part of a combined radio-chemotherapy approach, which, if timed correctly, can increase the effectiveness of radiotherapy in some cancers.
A number of new concepts have been developed, which use radiotherapy and chemotherapy in combination, not only simultaneously but also in a sequential or alternating format.
You will be well cared-for throughout your stay, with your medical needs being managed by specialist doctors and your nursing care in the hands of staff with special training in cancer care.
In addition, our Social Services Team will be available to answer common care-related questions on issues such as financial problems and care following discharge (beds, care aids, wheelchairs, rehabilitation, etc.).
Die Fachkompetenz unserer Klinik fließt außerdem in folgende interdisziplinär arbeitenden und zertifizierten Zentren ein:
- Brustzentrum Ludwigshafen
- Darmzentrum Rheinpfalz
- Darmkrebszentrum am Diakoniekrankenhaus Mannheim
- Hauttumorzentrum Rheinpfalz
- Onkologisches Zentrum Ludwigshafen
- Pankreaskarzinomzentrum Rheinpfalz
- Prostatakarzinomzentrum Rheinpfalz
Nuclear medicine services for our patients are provided by the Nuclear Medicine Unit, which is led by Dr. Bernd Sattler, and is located within the Hospital grounds.
Nuclear Medicine Unit
Nuclear medicine is a branch of medical imaging that uses radioactive isotopes or small amounts of radioactive materials, called radiopharmaceuticals, to analyse molecular activity within organs and tissues. Nuclear imaging scans are also referred to as scintigraphy images and are taken using gamma cameras.
The Nuclear Medicine Unit is led by Dr Bernd Sattler and supplies the various specialist units of the hospital with the full range of functional diagnostics and testing methods on offer. Dr Sattler is also responsible for the Radioiodine Therapy of benign and malignant thyroid disorders on Therapy Ward ST02.
The unit also specialises in the treatment of joint diseases (Radiosynoviorthesis/RSO).
Range of service offered:
- Nuclear thyroid scans
- Follow-up treatment for thyroid disorders
- Cardiac diagnostic procedures (known as "gated SPECT myocardial scintigraphy")
- Nuclear bone scans
- Nuclear lung scans (ventilation and perfusion)
- Nuclear renal scans
- Nuclear brain imaging
- Tumour diagnostic procedures
- Radioiodine Therapy
- Therapy of joint diseases (RSO/Radiosynoviorthesis)
- Systemic therapy for painful bone metastases
Praxis für Nuklearmedizin
German Society for Radiation Oncology
For further information please click here.