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Brachytherapy is also termed short

Defreezing also has a special importance, i. Natural, especially peritoneal cavities, can be used by surgical route for the purpose of visualization, but also in order to sample material for microscopic examination. The manipulation of the tumor mass during the operation will be minimized, in order not to facilitate the diffusion of malignant cells in adjacent tissues. During thawing, arterioles and venules contract immediately and resume a reduced blood flow with the almost instantaneous and continuous production of thrombi.

Stasis starts from the venous part, the capillary flow is diminished and consequently, the arteriolar flow is slowed down. Nerve and muscle cells are relatively radioresistant, since they do not divide, while bone marrow, intestinal and skin cells are radiosensitive, as they normally have a higher mitotic index. Cell structures are not lost and the effects of severely damaged electrolyte concentrations and pH changes do not manifest.

Cells from other areas, especially from the slow freezing region, freeze more slowly, thaw more rapidly and have a better chance of survival. Infiltration anesthesia is recommended in the intervention area. This review, therefore, focuses on a discussion of current thinking in biomarker assay validation.

The distance between

In this way, metastases and some complications can be avoided. Here occurs the most rapid heat loss. Consequently, combined therapy radiation, chemotherapy and hyperthermia is recommended in order to reduce the heterogeneity of tumor response. The therapy of cancer disease recognizes that surgical intervention is the most effective and practical method, which requires an adequate control of the technique specific for each case.

Endoscopic techniques, such as gastroscopy, colonoscopy and laparoscopy can avoid the performance of laparotomy. Incisional biopsy provides material for microscopic diagnosis, without the complete removal of the tumor. Multiple, successive freezings in the same location will interfere with the blood flow, inducing a decrease in the heat flow from the ice ball. It should be mentioned that surgery is local therapy in a disease that is essentially systemic. Normal tissue can be maintained because the extension of the ice ball can be controlled.

An increased radiosensitivity have lymphomas, testicular seminomas, carcinomas, while malignant connective tumors sarcomas are much less sensitive. Cicatrization occurs by granulation tissue. Slow thawing allows the recrystallization of small ice crystals into large crystals, stimulating the tissue fragmenting effect of ice. Although frozen, after thawing the main blood vessels will continue to supply with blood the tissues incorporated in the ice block, while arterioles, venules and capillaries are seriously affected.

The distance between the radiation source and skin, as well as the distance between the source and the tumor are elements that will be defined before the initiation of treatment. Brachytherapy is also termed short direct radiotherapy or curitherapy. The radiosensitivity of a normal tissue is proportional to the mitotic index. Rapid freezing does not allow the time needed for the increase of large crystals or the loss of compartmentalization, small ice crystals being thus formed all through the system. Radiotherapy can be administered using extremely varied equipment.

Each unit is characterized by the type and energy of radiation produced, the difference consisting in the penetrability and absorption of the different tissue radiations. The tolerance of normal tissues varies considerably, being influenced by the tissue type, the intensity and duration of treatment, the fractioning of radiation and other local and general situations. The most effective techniques for the rapid freezing of neoplasms will include all areas, even the deepest ones. In addition, advanced age makes the veterinary doctor delay surgery. Preventive surgery can be applied by the excision of the benign, premalignant or in situ tumor, which prevents the possible onset of invasive malignancy.