This is the normal body of the individual who has the cancer. Sounds inappropriate in some ways but that is the way it is used. The patient's immune system is working properly. They are capable of fighting off environmental invaders like infection normally. A biopsy in which only a part of the suspect abnormality is removed.
Classic technique involves open surgery and removing part of the lesion.
Infrequently done by classic technique today unless sampling error is likely by other incisional techniques. Other techniques are various types of needle biopsy. The ability for the malignant cells to invade normal tissue, thus compromising the functional status of the tissue invaded. Invasion may be direct or indirect. Our concerns are the same.