Cancer. Oncological diseases are manifested in malignant tumors arising from epithelial cells in various organs and tissues of the organism. Oncological diseases develop when normal cells degenerate to the tumor ones.
Oncological diseases include the following forms: cancer, sarcoma. This is a malignant tumor that most often grows in the bone, muscle or brain tissues. Lymphoma and leukemia. These are the malignant diseases of blood system when white blood cells degenerate. Main factors that provoke the development of cancer diseases are as follows:
smoking, both active and passive; excessive alcohol consumption; polluted habitat; influence of toxic substances on the organism; hormonal disorders; prolonged exposure to ultraviolet light (sunlight); injuries of skin lesions.
Oncological diseases develop in the human body for decades, frequently with no symptoms at all. People often confuse the first manifestations of cancer with the symptoms of other less dangerous diseases that makes the diagnostics more complicated.