Cancer cells
Cancer is an ‘abnormal growth of cells’. The cancer cells continuously multiply in spite of lack of ‘space’ and ‘nutrition’. Cancer cells can be differentiated from the other healthy cells in being different in shape, improper function and the capacity to spread to other parts of the body. The study of cancer and tumors is called as ‘Oncology’. Cancer is not a single disease but is a group of diseases.
Tumors can be benign or malignant.
Benign tumors grow slowly and do not spread. When tumors are malignant,
they are termed as ‘cancer’ and can cause harm including “death”. The
‘malignant’ nature of cancer is due to its locally invasive nature
(tumor invading the surrounding cells) and metastatic nature (tumor
invading the other tissues in the body).
The original tumor is called as the
primary tumor. The cells of the primary tumor travel through the
circulatory system and lymphatic system to form new tumors called as
secondary tumors in other organs.
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