What Are the Different Stages of Prostate Cancer?
The growth and spread of cancer are two important factors in deciding the most appropriate treatment options for prostate cancer. The growth of cancer decides the prognosis of the person. Staging is the term used to describe the location, growth, and spread of a cancer. It is based on a number of diagnostic tests, including the biopsy. The cancer may grow within the prostate gland for years and then gradually spread to other organs in the body.
The spread of cancer may happen in different ways, such:
- Invasion of the neighboring tissues of prostate gland
- Spread of cancer through the lymphatic system
- Metastasis through the blood to distant organs of the body
Different diagnostic tests, like biopsy, a digital rectal exam, ultrasound, MRI, CT scan of the abdomen, and MRI of the skeleton, may all help to derive the stage of the prostate gland.
Stage of a cancer is described by the TNM system that describes the three different aspects of cancerous growth – the tumor, nodes, and metastasis. ‘T’, or tumor, gives the size of the cancer, ‘N’, or nodes, describe the extent of spread of the cancer, and ‘M’ gives the spread of cancer to distant organs like liver and bone. In some cases, the TNM system of classification is combined with other systems like, Gleason score, to describe the stage of prostate cancer.
- Stage I – This is the microscopic form of prostate cancer and may not be visible in the digital exams of the rectum or the usual prostate scans. It is usually found incidentally during a test for benign prostatic hyperplasia. It is restricted to the prostate gland, and has not spread to the nearby lymph nodes or to any other organs of the body.
- Stage II – The tumor in the prostate gland is still small and may be or may not be seen in the imaging tests. However, the size of the tumor is bigger, and can be often felt during the digital rectal examination. The cancer has not spread beyond the gland. The cells of the tumor are abnormal. Cancer at this stage has not spread to any other organs in the body.
- Stage III – Cancer at this stage has spread to the nearby tissues just outside the prostate gland. It often spreads to the seminal vesicles, but not to the lymph nodes or any other part of the body.
- Stage IV – This stage describes the cancer that has spread to other parts of the body, like the bladder, liver, lungs, lymph nodes, or the rectum.
Identifying the correct stage of cancer is very important to decide the best treatment options. One may need to go through the different diagnostic tests to identify his stage of cancer.
