Therapeutic possibilities of techniques of extracorporeal blood circulation in oncology

Malignant tumors in an advanced phase of diffusion have a very poor prognosis. However, there are conditions in the body which may impede, even if only partially, further spread of the disease. In addition to currently available treatments, other favorable conditions can help to improve the prognosis, even if only relatively, such as the presence of inhibitors of metalloproteinases, antiangiogenic factors, the absence of particular proteins that favor tumor development, and the possibility of positively activating the immune system. The authors believe that in cases where such conditions are concurrent, the addition of a new favorable condition could be very useful. On the other hand, cases of total spontaneous regression of malignancies, even if in metastatic diffusion, are well known. It was recently emphasized that the spread of metastasis of renal cell carcinoma, arising in patients on hemodialysis for a long time, is considerably reduced at the post-mortem examination compared to patients with renal cell carcinoma and not on hemodialysis. This may suggest a positive effect exerted by the dialytic membrane on metastatic spread. The authors hypothesize that extracorporeal circulation of the blood, used mainly for cardiovascular interventions and hemodialysis, could be used by applying filters suitable for cancer treatments, similar to those used in hemodialysis, even if without accomplishing the hemodialytic function, provided there are no objections to their biocompatibility. In this case, the block of metastatic cells could lead to a relative increase in the cellular elements of the immune system (NK cells and T lymphocytes) compared to cancer cells, or rather to the relative reduction in the number of cancer cells compared to NK cells and T lymphocytes. Such a block would prevent any feedback reactions, so frequent and damaging to the prognosis when using overall medical stimulation for the immune system.