Know Your Options

Radiation oncology is a unique medical specialty - not only because it harnesses the powers of radiation in a way unlike anything else in medicine, but also because it is rarely part of the undergraduate medical curriculum. Only those doctors who train to become radiation oncologists after graduation from medical school spend enough time with the discipline to understand it. With every respect for their knowledge, your family doctor, internist, surgeon, or even your medical oncologist will not likely have seen enough of radiation oncology to give you accurate information about what will happen when you attend for radiation therapy. They do not "order" radiation therapy as they would a diagnostic x-ray; rather, they refer you to a radiation oncologist as another member of the cancer management team, for an opinion on what would best help in your care.

The concept of a team in cancer management is essential to your receiving the best possible care. As recently as the 1970s much of cancer care was territorial - the surgeon or the radiation oncologist would feel that no other services were necessary to give a patient the best possibility for controlling or curing their cancer. Much has changed in the past 30 years: the development of effective chemotherapy, giving us a third approach for caring for and curing cancer patients; new technologies for prevention and early diagnosis that rolled back the boundaries of what we could cure; and the adoption of a comprehensive approach to cancer management that recognizes clear evidence that patients are cared for better when all the disciplines that can influence a patient’s well-being and outcome - surgery; radiation oncology; medical oncology (chemotherapy and biological therapies), primary care; psychiatry, psychology, and social work for supporting patients and family members; integrate their efforts according to rigorously-tested evidence that maps the road to the best outcomes. In the year 2000 and beyond the best care unifies all these professionals in a cooperative effort to support and care for their patients through treatments that have been rigorously tested and shown to be effective.

Cancer treatment requires that everything that can be known about the disease and the patient should be known - what kind of cancer, exactly where it can be shown to be, and the risks it may present for hidden involvement in other areas.  It also requires that each professional discipline contributes in a way that is effective against the cancer, preserves normal function as much as possible, anticipates and deals with other health problems the patient may have, supports that patient and his family emotionally, and respects the patient's needs, wishes, and values. This is the comprehensive approach to which all contemporary cancer care - and we - subscribe. In radiation oncology practice, this means applying and staying current with the ever-growing body of knowledge the exact dose to be given, over what period of time, to how large a volume of the body, how that dose should be integrated with chemotherapy and surgery, and how to reduce or mitigate the risks of aggressive treatment. Not meeting these objectives reduces the treatment effectiveness.

For patients coming to radiation therapy for symptom control and enhancement of quality of life in the face of incurable disease (referred to as "palliation") the treatment alternatives for radiation therapy are much broader and can be closely individualized to the needs and frailties of the individual patient. Palliative radiation generally means shorter courses of treatment, lower doses and correspondingly less risk of side effects and complications.

About Your Consultation

Your first visit to a radiation oncology center will likely be for a detailed consultation with a radiation oncologist. Any recommendation for radiation therapy must be based on a detailed evaluation of the patient - the individual circumstances, the nature and extent of the disease, the general state of health, and patient beliefs and values. Frequently this involves an assessment of other medical problems and risks, family dynamics, and choosing the best of several alternative approaches within the bounds of what is practical and compassionate for the patient.

The purpose of this consultation, then, is for the radiation oncologist to assess the patient, the disease, and to develop an understanding of what can and should be done for the patient's best interests; and for the patient and his family to understand what is being offered and what alternatives might exist. Using a conventional history and physical examination, laboratory studies, and a great reliance on imaging to define exactly what is and what is not involved with the cancer, the radiation oncologist develops a comprehensive plan for the treatment. This plan should consider:

• Exactly what needs to be included in the treated area - the detectable tumor and areas at risk for spread;

• What normal tissues and organs are in or near the area to be treated, how much radiation they can tolerate and still recover, and how best to exclude or protect them;

• The total radiation dose that will be needed to create the effect desired;

• How much of that dose should be given and how often - to treat the tumor adequately, to spare the normal tissues and reduce the risk of problems during (side effects) and after (complications) the course of therapy, and to integrate the radiation process into other treatments the patient may be receiving.

The radiation oncologist will define a comprehensive treatment plan, disclose any issues to the patient and allow the patient to make an informed decision about proceeding. This last point is paramount. Each patient is in control; the best any physician can offer is well-developed recommendations - the final decision rests with the patient.

About Treatment Planning and Simulation

Once the consultation has been completed, the radiation oncologist has formulated the treatment plan, the patient agrees and the referring doctors are informed, it's time to move ahead with putting the plan into action. The plan and its execution remain under the direction of the radiation oncologist - but at this point other professionals join in to ensure that the treatment is accurately delivered.

The first step after the consultation is treatment planning. The purpose of any radiation therapy program is to deliver a lethal amount of radiation to the cancer - but from the beginning we must consider how this can be done safely. We must avoid delivering equally high doses to normal tissues next to or intimately involved with the tumor. External beam radiation therapy treats a deep-seated tumor from outside the body, and radiation beams pass through normal structures enroute to the tumor. It is usual to treat the tumor from two or more entry points with radiation beams that meet and "crossfire" the target volume deep within the patient’s body; this limits the radiation dose to the organs and tissues passed through to a safe level.

Often the radiation oncologist will request specialized imaging studies - most often CT or MRI imaging of the area of the body to be treated with the patient in the same position as will be used for treatment - to allow computerized mapping of the dose to be delivered into the tumor volume and adjacent organs as seen on the scan. This ensures that the entire tumor will be treated to a uniform and sufficiently high dose in a way that spares as much of the normal tissues and organs nearby as possible. It is usual to plan for the total area being treated to be reduced periodically during the course of therapy, and to move the entry points of the radiation beams, so that by the end of the whole program the highest radiation dose has been delivered to the smallest volume with the greatest concentration of cancer cells. By using shrinking fields and changing the treatment plan to bring the treatment beams through different areas of normal tissue on their way to the target, more and more of the nearby normal tissues can be excluded from receiving radiation. The treatment as planned should be precise, repeatable, comprehensive, and effective.

The next step is a simulation. This is a "dry run" of the proposed treatment, guided by the radiation oncologist's understanding of the disease and planning already performed. Using a diagnostic x-ray/fluoroscopy unit that exactly parallels the functions of the external beam radiation treatment machine (the simulator), the planned treatment portals - the points of entry for the radiation beams - are drawn on the patient. X-rays are taken to verify that the plan does in fact treat the necessary regions of the body, and that the portals can be set precisely and reliably day after day through the course of treatment. The patient 's skin will be marked to guide the treatment setup from day to day, and measurements will be taken of the patient's body to reconfirm the computer plan and to allow final computerized calculations of radiation dose.

At this time custom treatment devices will be made for most patients. Some of these - face masks, foam plastic cushions - form to the shape of the patient's body to ensure that all treatments are accurately targeted at the same point. Others - lead alloy blocks - are shaped to exclude as much normal tissue in and near the portals as possible to ensure that radiation is delivered only to the tissue that must be treated. Through all this process the radiation oncologist is supported by therapists who make the devices and will deliver the treatment as prescribed, and a staff of radiation physicists and dosimetrists who develop the details of the treatment plan, confirm the accuracy of dose delivery, and help to monitor the precision of the daily treatments. Once the treatment is planned, the simulation competed, the devices fabricated, and the calculations completed, the patient is ready to start treatment.