Prostate Cancer Diagnosis
The prostate cancer diagnosis is based on the triptych:
- PSA – that is the Prostate Specific AntigenProstate cancer καρκίνος προστάτη and is used for the dection of disorders at the prostate gland. Prostate Specific Antigen consists a glycoprotein that serves semen liquidation. PSA is secreted from all prostate cells, both hyperplastic and malignant. In malignant prostate cells, PSA is produced in a triple to normal quantity. Thus, in prostate tumor, PSA is increased. It should be emphasized that increased PSA levels does not always mean that the patient has prostate cancer. At the same time, normal PSA levels do not ensure normal prostate state. In all cases, there are some types of prostate gland’s cancer cells that do not elevate PSA secretion. Therefore, it prostate cancer is very difficult detected at early stages.
- Prostate rectal exam – consists an integral part of prostate cancer diagnosis after any suspicious finding regardless PSA levels.
- Biopsy – biopsy is performed under sedation and local anesthesia in order to be painless. If an abnormal area is detected during transrectal ultrasound, biopsy sample will be taken from this area. If no pathological indication is found, 10 to 12 biopsy samples will be taken from different prostate areas. Very large in size prostate may require more than 12 biopsy samples in order to provide an adequate randomized clinical image and allow correct cancer exclusion. After biopsy procedure, the patient may experience a little blood in the urine, semen or faeces.
Biopsy results may be:
- Negative – i.e. no sign of cancer;
- Prostatic intraepithelial neoplasia presence – PIN;
- Positive – i.e. cancer existence.
High PIN, coexists with prostate cancer at a rate ranging from 50% to 85%, while the low PIN levels indicate a 20% prostate cancer incidence.
In case of a positive biopsy, further information will be rquired regarding the exact type, character and the “severity” of cancer:
The percentage of cancer is calculated within the microporous rolls received from the biopsy sample. The steps that direct the specialized urologist to further examining steps is the malignancy degree. Malignancy degree is expressed in Gleason units and is classified into units (score) ranging from 2 to 10.
Thus, Gleason score in relation to PSA levels consist the key elements that determine the prognosis of prostate cancer. The Gleason score of >6 is usually considered as a mild degree of cancer malignancy, with optimistic perspective. Gleason score of 7 or more indicates aggressive prostate cancer.
If a prostate biopsy confirms the cancer existence, the next step is to determine malignancy degree or cancer aggressiveness. In other words, we estimate how fast cancer may expand.
Tumor cells may vary in shape and size. Some cells may be aggressive, but others may not. Biopathologist will determine the two greatest lesions that contain tumor cells. In these regions most aggressive forms of cancer cells will provide the degree of prostate cancer grade. The most common malignancy grade of prostate cancer cells ranges between 1 and 5, i.e. 1 is the least aggressive cancer.
Gleason score may also help determine the best form of therapy for each patient.