Medicine is both the beneficiary and victim of traditions.
The benefit comes from the credibility afforded to medicine, translated into the respect afforded doctors. There is a tradition of professional excellence, enforced by a licensing mechanism and a legal system that monitors quality.
Traditional forces are conservative, They encourage the continuation of "standard practice." Usually that is a good thing. Standard practice is usually the best available course. But the tradition is a force that retards change, and sometimes change means improvement.
All traditions, medical or otherwise, are the products of history, and as such, preserve a wisdom and perpetuate myths.
A core tradition in medical oncology is that more toxic treatment is more effective treatment. This stems form the history of the field ( see: The Emperor of all Maladies) . The first successes in treatment of cancer were seen when therapy was brought to an intensity that carried a significant chance of toxic death, death from the treatment itself ( not the disease). That tradition carries through to the present. When cancer cases are discussed in conference, the question of dose is always raised.
But the notion that higher dose yields better results, has often not been tested in most circumstances. The dosage of drugs is established in Phase I clinical trials, These trials include desperate, heavily pre-treated patients with clearly heterogeneous primary and secondary problems. These trials usually assume the optimal dose is at or near the maximum tolerated dose . Once that dose is established, it becomes cowardly to reduce the dose, unless forced to do so by toxicity. I am not sure that the approach is globally valid.
The classification and treatment of cancers based upon microscpic appearance, That is a tradition. The appearance of cells in the microscope and the impression of analogy to aberrant normal tissue dates from Virchow (1821-1902). This approach organizes the treatment of cancer, but it has other consequences.
There is currently a battle between the microscope and molecular biology for the orimacy in diagnosis. The molecular biology sometimes identifies mutations that may be fundamental to the cancer process and these mutated gene products can be the targets of therapy. Frequently, neither of these happens. The mutations are of unknown significance and the targeted agents work poorly, or not at all ( at $10,000 per month). But even when clear targets emerge, they struggle against the tradition of the microscope for recognition.
Sometimes, treatment does not change despite a better understanding of the disease process. Lymphocyte predominant Hodgkin disease is an example. Hodgkin Diseases is a set of lymphomas that are caused by a very distinctive appearing cell: the Reed Sternberg cell. Cells with a similar appearance are characteristic of a disease called Lymphocyte Predominance Hodgkin Disease, but it has been known for 30 years that this is a non-Hodgkin lymphoma.
The traditional treatment for Hodgkin is ABVD, a mixture of toxic medicines that can damage the heart, lungs, nerves and immune system. This combination is not standard for Non Hodgkin lymphoma....except for lymphocyte predominant Hodgkin Disease, because that is the tradition. ( I do not follow this tradition). Continuing to use a regimen that has worked in the past is a very reasonable approach, but the Hodgkin Disease regimen has considerable long term toxicity.
Tradition is a reasonable fall back position, especially when it has a good track record. It should not stand in the way of progress. There is value in tracing how we come to treat certain diseases in certain ways. Often, there is no basis at all.
Tradition has a role, but it must be subject to scrutiny.
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