How To Diagnose Prostate Cancer?

Symptom

What does a prostate cancer patient feel?


Prostate cancer patients may have a range of symptoms – from none in early disease to multiple symptoms in advanced disease. An outline is given below


  • No symptoms at all
  • Urinary symptoms such as difficult urination, slow stream, blood in urine,
  • Bone pains , low back ache
  • Loss of appetite , weight

There are a range of other uncommon presentations of this cancer.


Clinical Examination

Examination of prostate gland through back passage by an expert UroOncologist is extremely useful in suspecting the cancer as well as helping in targeting the biopsy later.


Blood Test

Prostate specific antigen (PSA) is a blood test , available widely in India in almost every diagnostic lab. There are age specific values , above which the suspicion of cancer increases.

PSA is bound in the blood with protein particles. Assessing the ratio of free (F) to total (T) PSA in the blood helps us to judge the likely hood of diagnosing cancer. In addition to prostate cancer, other issues that could cause elevation of PSA includes


  • Benign enlargement of prostate
  • Infection
  • Recent sexual activity
  • Bicycle use
  • Instrumentation

Imaging

MRI is the most important test in the diagnosis of prostate cancer. Especially Multiparametric MRI of the prostate gland has increased the accuracy of the diagnosis of the cancer. It helps us to identify areas where subsequent biopsy could be targeted. It also gives us information about the nodes in the pelvis and the imaged bones. However the suspicion on MRI should be further confirmed with biopsy of the prostate gland. Currently, MRI is done before the biopsy in order to improve the accuracy of the biopsy. MRI also gives us information about the extent of the disease in the prostate, its surrounding tissues especially the vas , seminal vesicles and rectum. When PSA level is high and / or suspicion of high risk/ high grade prostate cancer , a bone scan is done to assess the spread to bones. This could be done using Diffusion weighted MRI ( DW MRI) or Nuclear medicine technique ( Tc99 Bone scan ) Nuclear medicine bone scan is done by a whole body scan 3 hours after an injection of a radionuclide. Abnormal uptake of the radionuclide increases the diagnosis of spread of prostate cancer to bones. PSMA PET CT with MRI fusion is not the most popular method of imaging the prostate cancer patients. It gives information both from local extent of the cancer as well as distant spread. This test is widely available in India. Transrectal Ultrasound scan ( TRUS) is useful assessing the size of the prostate size, presence of middle lobe of prostate and taking systematic as well as targeted biopsy.


Biopsy of the Prostate Gland

Biopsy is done using along trucut needle and TRUS guidance as a day care procedure. As described before, it could be standard systematic biopsy covering all parts of the prostate gland especially the peripheral aspect where cancer happens commonly. Additional biopsy is done on targeted areas identified on MPMRI or in the transition zones or seminal vesicles depending on the clinical situation. The procedure is done normally under local anaesthesia and rarely under general anaesthesia. An antibiotic dose is given before and a course is given after the procedure. After the procedure, it is common to notice some blood in the urination, back passage and in the semen lasting for a few days and rarely few weeks. Two important side effects of the procedure ( even though uncommon) are Infection ( as evidence by high temperature , shivering , unwell) and urinary retention ( as evidence by inability to pass urine). Both of these side effects need immediate hospitalisation. The tissue thus taken is sent for pathological examination. Transperineal prostate biopsy is slowsly becoming popular replacing the transrectal route