Pernicious cachexia: a different view of cancer.
Кључне речи
Апстрактан
Despite intensive effort to cure breast cancer, treatment generally fails, as evidenced by the age adjusted mortality from breast cancer. For 60 years, breast cancer mortality remained virtually constant. As treatment failed to improve the life prospect of the average patient, it is based on false premises, e.g., Halsted's hypothesis, according to which the tumor is the only threat to the patient. Yet there is more to cancer than just the tumor. Two hallmarks of cancer, cachexia, and paraneoplasia, are usually ignored, since it is assumed that they are caused by the tumor. But, what if it is the other way around, and cancer is first of all a cachexia accompanied by a tumor? At least this could explain why in most cancers treatment fails. Cancer is a chronic systemic disease with local manifestations. Like arteriosclerosis, that is also systemic and manifested solely by its local manifestations, e.g., stroke and myocardial infarction. In the same way as treatment of an ailing heart does not cure the underlying arteriosclerosis, tumor removal does not cure cancer, since being "metabolically" systemic. It is proposed here that carcinogens deplete a vital substance and induce a metabolic deficiency that ends in cachexia. In order to survive, the organism grows a protective organ, the tumor, that replenishes the missing substance. During pre-clinical phase of cancer, deficiency is slight and compensated even by a minute tumor. With time it gets worse and the tumor has to grow more and more in order to make up for the loss, causing pain and secondary damage to vital functions. The patient seeks help and the disease starts its clinical course. When deficiency worsens, the patient becomes cachectic and dies. Such a metabolic relationship exists in pernicious anemia, that illustrates how a tumor might be protective. Cancer is viewed here as pernicious cachexia induced by the loss of a vital metabolite and compensated by the tumor. Until the discovery of the missing substance, treatment ought to preserve the tumor and alleviate its secondary manifestations.