Linear Accelerator Treatment Facilities
What Facilities are like
Cancer treatment facilities are often housed in large hospitals, but some are stand-alone cancer treatment centers. Those associated with hospitals are more likely to be non-profit, while those that stand alone are more likely to be for-profit organizations. Financial pressures are likely to be strong at both for-profit and not-for-profit organizations, but they will have slightly different regulatory structures.
During the time of Therac-25 (the mid 80s) a well equipped treatment facility might have 3 different machines. The machines would be capable of producing different kinds of radiation, different strengths of beam, and capable of different kinds of exposure to the patient. Each of these machines would cost, for the machine alone, between 1 and 2 million dollars. In addition, special housing for each machine is needed, with shielding in the walls, adequate power supply, video and intercom links, etc.
Operators would be needed to run each machine. For larger facilities, a supervisor of the operators, with more training and experience might be needed. In addition, at least one MD specialist in cancer radiation therapy (a Radiation Oncologist) would be required. Finally, a medical physicist would be needed to maintain and check the machines regularly. Some facilities contract out the services of a medical physicist. Finally, all the support personnel for these specialists (nurses, secretaries, administrative staff, people to handle billing and paperwork, janitorial staff, etc.) are required.
Machine Support and Maintenance
Medical Linear Accelerators do age over time, and older machines often produce more errors. Five to ten years is a reasonable life span for a machine. Thus, simply to maintain a set of three medical linear accelerators, an institution can expect to spend 1 to 2 million dollars every third year.
Sometimes errors can be resolved and machine kept longer using software upgrades or upgrades or retrofits of machine parts. The companies that sell linear accelerators charge maintenance contracts that can include different levels of support. Because of monetary constraints, sometimes facilities are forced to choose between software updates, manuals, and training for operators and physicists. All this is in addition to the price of the machine itself.
Production pressures are always present when an expensive medical technology is being used. These very expensive machines need to treat enough patients to pay for themselves over their lifetime. And in for-profit medical facilities the additional pressure of generating a profit is added to this production pressure. Another kind of production pressure is generated because of concern for the patient. Patients schedules require treatments on certain days and it disrupts the patients lives and slows down their treatment to have to reschedule them for another day while the machine is being checked out.
These production pressures generate the desire to "push patients through." If a machine gives only a portion of the prescribed dose, an operator will often repeat the treatment with enough radiation to add up to the total prescribed dose. Of course, because of liability issues and concerns for patient welfare, this can only be done when it is thought safe.
One of the advantages of the significant computerization of the Therac 25 machine was that setup for treatment could be done much more quickly. This allowed the operator more time to speak with the patient and interact with them about their health concerns. In addition, this increased efficiency allowed more patients to be scheduled during a day. Thus, more patients could be treated, but the atmosphere was not reduced to that of a factory.
Liability and Trust
Facilities that run medical linear accelerator are surely concerned about liability for injury to patients that might occur. Insurance, for medical providers, is quite expensive and errors in treatment can result in lawsuits, which in turn produce increases in insurance premiums. Standard practice in litigation is to "sue everyone with deep pockets." This means that even if an error is the result of poor design of a linear accelerator, the facility itself will be sued simply because they were involved: they have insurance and thus "deep pockets."
But it is in the interest of facilities to reduce errors without the threat of lawsuits. When a treatment must be restarted several times because of errors, it may reduce patient confidence in the facility. This can mean patients moving to another facility with which they are more comfortable.
Finally, medical professionals are in their business because they want to help people and have the knowledge and skill to do so. So a primary motivation of medical professionals is patient welfare.