It is a mass of tissue which is abnormal in nature. A tumour is formed when the cell growth and division take place more than it should or when the cell does not seize to exist when it should. A tumour may or may not be benign.
INITIAL STAGES OF CANCER:
A tumour when found in a particular area in the body found to be cancer causing is not removed, the cancer can spread through different organs which can also be far from the origin of the tumour. This spread of cancer through the body is called – Metastasis. The onset of this process takes place when the cancer-causing tumour contaminates the normal tissues found in the body. this spread takes place through three means – Transcoelomic, Lymphatic and Hematogenous.
TRANSCOELOMIC – it spreads through the cells in the cavities of our bodies, known as Peritoneum.
HEMATOGENOUS – when the cancerous cells spread through blood vessels.
LYMPHATIC – when the cancer cells take over the lymph nodes of the body and travel via the lymphatic system of the body.
Through proliferation the cancer-causing cells form tumours known as micrometastases at new places and areas in the body. these tumours grown into becoming full sized tumours in the body. This completes the process of Metastasis.
SEED AND SOIL THEORY OF METASTASIS – the theory by the English Surgeon – Stephen Paget states that the cancer cells can easily die in the unfavourable microenvironments for the growth of these cells. Which makes them only metastasis in the location similar to their origination.
James Ewing, first professor of Pathology at Cornell University stated that the sight at which the metastasis takes place is down to the vascular and lymphatic channels.
Both the theories are said to carried truths that are important to the study of Spread of Cancer. The full truth though, compromised factors revolving around the properties of the cancer-causing cells, the immune systems and its effectiveness.
Although the whole truth is yet to be discovered behind metastases, but the study of advanced cancer and its cure can help build really effective answers in curing this disease.