Certain cancers may be detected by routine self-examinations or screenings (for example, breast cancer, cervical cancer, skin cancer or prostate cancer); some may be discovered ‘accidentally’ when tests are performed for a different illness; or when certain symptoms persist, or the presence of a tumour is detected.
A diagnosis will usually begin with a thorough physical exam and medical history, and the healthcare provider will order blood tests. Establishing the presence of cancer will always involve testing tissue samples for the presence of abnormal cells that are taken with a biopsy and tested by a pathologist. We take a look at some of these cancer detection methods in more detail:
1. Needle biopsy
- A fine needle biopsy involves using a fine needle attached to a syringe to remove fluid and a small amount of tissue from a tumour. If the tumour is deep under the skin, the process is accompanied by an ultrasound or CT scan that allows the needle to be guided correctly.
- A core biopsy uses a slightly larger needle to remove a cylinder of tissue – this procedure is performed with a local anaesthetic.
2. Excisional or incisional biopsy
A surgeon removes the whole tumour (excisional) or a small part of the tumour (incisional). Either a local or general anaesthetic will be used for this procedure.
3. Endoscopic biopsy
An endoscope is a thin, flexible tube that has a light and lens on the end. There are different kinds of endoscopes depending on which part of the body is being examined. Endoscopes can explore the oesophagus, bronchi, lungs, colon and rectum.
4. Laparoscopy
A slightly different scope is used to look at the inside of the abdomen and to remove tissue samples for testing.
5. Laparotomy/thoracotomy
During a laparotomy, an incision is made in the abdomen to enable the surgeon to remove a sample of suspicious tissue. This is usually done when a needle biopsy or laparoscopy cannot be performed. When the same procedure is performed in the chest cavity, it is called a thoracotomy.
6. Skin biopsy
There are a number of skin biopsies that can be used, depending on the kind of tumour, for example, a shave biopsy, which takes a sample of the outer layers of the skin; but a punch or excisional biopsy may be necessary if melanoma is suspected. These can remove deeper layers of the skin and can also be used to find out how deeply a melanoma has gone into the skin.
7. Lymph node mapping
Using a slightly radioactive material and/or dye, a surgeon can establish which lymph nodes in the area of the cancer have been affected. If this so-called ‘sentinel’ node is detected, it is removed and tested.
8. Imaging studies
Imaging studies are also commonly used to help doctors to detect abnormalities that may be cancerous. X-rays, CT scans and MRI scans and ultrasounds are commonly used to assist in diagnosis.
Once a definitive diagnosis has been made, the stage of cancer is established in order to commence with the most appropriate treatment or combination of treatments such as surgery, chemotherapy and radiation.
For more information
CHOC Childhood Cancer Foundation SA: www.choc.org.za or call (011) 326-1717
The South African Childhood Cancer Study Group: www.saccsg.co.za
Cancer Association of South Africa: www.cansa.org.za (CANSA offers support to parents of children who have been diagnosed with cancer. Email [email protected] to find out more about their TLC Support Groups.)