Early Prostate Cancer Detection
According to the latest statistics reported by American Cancer Society (1), prostate cancer is the second most frequently reported malignancy in males. However, with early detection and prompt treatment, most cases can be resolved completely without affecting the overall survival rate and life span of the patient. The 5-year survival rate of prostate cancer is almost 100%; the 10-year and 15-year survival rate is 99% and 94% respectively (suggesting that a high percentage of patients survive if prompt measures are taken)Based on the latest data, there are over 2 million prostate cancer survivors in United States alone.
What Should You Know About Prostate Cancer?
Malignant transformation of the glandular matrix of prostate gland in males is referred to as prostate cancer. Normal gland is about the size of a walnut and is responsible for the secretion of prostatic fluid (or semen along with seminal gland secretions). According to latest projections, it is expected that 233,000 new cases of prostate cancer cases will be diagnosed in 2014. Likewise, mortality due to this malignancy may exceed 29,480 victims in 2014.Most cancers of prostate gland are adenocarcinomas (malignancy of glandular tissue); but other frequently reported varieties are small cell carcinoma, transitional carcinoma and sarcoma.Some signs and symptoms that may indicate prostate cancer are:
- Inability or difficulty in passing urine
- Hematuria (appearance of blood in the urine)
- Dull aching pain in the flanks, hip or pelvic region
- In advanced cases, the patient may also experience spinal pain, paresthesia, paralysis, bowel dysfunction, urinary issues, weight loss etc. due to distant metastasis.
Why Is It Important to Detect Early Prostate Cancers?
It has been observed that most cases of prostate cancer are preceded by Prostatic intraepithelial neoplasia (an early pre-cancerous condition) that may not result in full blown malignancy if detected and managed early.Periodic screening and assessment of prostate gland is advised by healthcare providers in order to:
- Detect pre-cancerous lesions
- Follow-up high- risk patients to advise preventive and therapeutic advise
- Detect and treat malignant lesions to prevent metastasis
According to the recommendations of American Cancer Society, every adult male should be screen for prostate cancer at the age of 50 years. Screening should be commenced early (at 45 years) in males who are at high risk of developing this malignancy; such as:
- Individuals who have a history of prostate malignancy in index degree relatives
- African-American ethnicity
- Individuals who have a history of PSA levels higher than 2.5 ng/dL at a previous occasion
How Can You Detect Prostate Cancer Early?
There are a number of sophisticated diagnostic modalities with high sensitivity and specificity.Digital rectal examination:Digital rectal examination is a preliminary screening test that is usually performed in high risk males who are manifesting some signs of prostate enlargement. The test involves insertion of a clean, gloved and lubricated finger inside the rectal lumen to feel the borders of prostate gland. Enlarged, rough or uneven borders suggests a malignancy.The benefit of conducting digital rectal examination is to detect lesions in individuals with normal serological investigations.PSA Tests:
Prostate- specific antigen is a special set of serological investigations that is performed in high risk patients who are manifesting signs of malignancy. Other indications of PSA tests is to determine if additional investigations are needed (such as prostate biopsy) to confirm diagnosis. There are several parameters that are assessed such as the Density of PSA, Age –specific range, Velocity of PSA etc.Few limitations of PSA test are:
- The PSA levels are very sensitive to certain drugs. Individuals who consume certain medications (such as herbal mixtures, statins, aspirin, diuretics and anti-hypertensive medications) may interfere with the accuracy of PSA test.
- Obese males tend to have lower levels of PSA despite an ongoing pathology.
- Certain urological procedures, physical activities (bicycling), prostatitis and recent ejaculation may also affect PSA levels.
- More than 15% individuals with normal PSA levels have active malignancy (on histological examination).
Biopsy of Prostate Gland:Individuals who have enlarged prostate gland on digital rectal examination and have abnormal PSA levels in serum are candidates of prostate biopsy (which is also the confirmatory test for prostate cancer). The procedure involves collection of a tissue sample from the gland and examination under a microscope to visualize malignant cells.This procedure is often preceded or followed by Transrectal ultrasound (TRUS).Other popular tests that are also used in the screening or detection of prostate cancer are; ProstaScintTM scan, CT scan, MRI and lymph node biopsy.References:
- Heidenreich, A., Bellmunt, J., Bolla, M., Joniau, S., Mason, M., Matveev, V., ... & Zattoni, F. (2011). EAU guidelines on prostate cancer. Part 1: screening, diagnosis, and treatment of clinically localised disease. European urology, 59(1), 61-71.
- Grimm, P., Billiet, I., Bostwick, D., Dicker, A. P., Frank, S., Immerzeel, J., ... & Langley, S. (2012). Comparative analysis of prostate‐specific antigen free survival outcomes for patients with low, intermediate and high risk prostate cancer treatment by radical therapy. Results from the Prostate Cancer Results Study Group. BJU international, 109(s1), 22-29.