Clinical Examination of Prostate Cancer - Case Study Example

 A 67 years old male complained of severe back pain of one week duration and increased frequency of urination and pain while urinating, of 2 weeks duration. Family history: his father is deceased, and had prostate cancer. Investigations: biopsy showed a well differentiated prostate adenocarcinoma. Computerized tomography showed an increased size of the prostate. There is a heterogeneous density and a small hypodense area, correspond to interior necrosis. Examination: blood pressure- 120/80; CVS: Clear S1, S2; Abdomen: Soft, nontender, nondistended, nontender, bowel sounds present; Back: Limited range of movement; Rectal exam: the sphincter tone is decreased, no blood. The prostate is enlarged and hard to palpation. Clinical diagnosis Whenever a prostate cancer is suspected, the clinical examination and tests may include: urine analysis for the presence of any blood or infection, a digital rectal examination, and blood test to measure the level of prostate-specific antigen (PSA). At times, especially when the results of the PSA are suspicious, the level of prostatic acid phosphatase (PAP) may also have to be checked (UCSF Medical Center 2007.) Anatomy From: Malecare. http://www.malecare.com/prostate-cancer_42.htm The prostate is an exocrine gland of the male reproductive system, which stores and secretes a slightly alkaline fluid, milky white in appearance. The gland is placed immediately below the internal urethral orifice and around the beginning of the urethra. The apex of the prostate is situated at the urogenital diaphragm while the base is situated at the bladder neck. The prostate is comprised of various zones, the peripheral zone, the central zone, and the transition zone. The central zone is a cone-shaped area, wherein the apex of the cone is at the meeting points of the ejaculatory ducts and the prostatic urethra at the verumontanum (Hammerich et al n.d.). The peripheral zone includes all prostatic tissue at the apex along with the tissue located posteriorly near the capsule. The transition zone includes prostatic tissue lateral to the urethra in the middle of the gland (Hammerich et al n.d.). The convexity of the anterior external surface is formed by the anterior fibromuscular stroma and has striated muscle at the apical half, with smooth muscle cells towards the base (Hammerich et al n.d.). The prostatic capsule is made up of fibrous tissue surrounding the gland. The seminal vesicles are located superior to the base of the prostate. Each seminal vesicle joins with the vas deferens on each side to form the ejaculatory ducts. The histology of the prostate shows it to be a branched duct gland (Hammerich et al n.d.) MRI & CT images of normal prostate and prostatic cancer MRI of normal prostate. MRSI of prostate cancer From:RadiologyInfo From: ucsf. www.ucsf.edu/multimedia/photography/details/67/ http://www.radiologyinfo.org/en/info.cfm?pg=mr_prostate CT image of normal prostate (p). CT Prostate cancer. From:Radiographics From: Radiology www. radiographics.rsnajnls.org/.../full/23/4/951/F3A www. radiology.rsnajnls.org/.../full/243/1/28/F4 Pathology Prostate cancer invading soft tissue around the prostate gland. From: BCM http://www.bcm.edu/pathology/labs/Ittmann/overview.htm After the initial transformation, prostate cancer develops due to further mutations of numerous genes (including genes for p53 and retinoblastoma). Ultimately, tumor progression and metastasis occurs (Theodorescu and Krupski 2009). The majority of prostate cancers (95%) are adenocarcinomas, while the morphology of approximately 4% of prostate cancers is of the transitional cell type (arising from the urothelial lining of the prostatic urethra). About 1 % has a neuroendocrine morphology, arising from the neuroendocrine stem cells normally present in the prostate or from aberrant differentiation (Theodorescu and Krupski 2009). Location wise, 70% of prostate cancers arise in the peripheral zone, 15-20% in the central zone, and 10-15% in the transitional zone. They can be locally invasive, and spread to the ejaculatory ducts, bladder neck and seminal vesicles. Later, they can penetrate through the prostatic capsule and along the perineural or vascular spaces. Early metastasis to the bone can occur. Distant metastases to the liver, lungs, and adrenal glands etc can also occur (Theodorescu and Krupski 2009.) Role of imaging modalities in the diagnosis Transrectal Ultrasound (TRUS)-involves the transmission of ultrasound by a probe inserted into the rectum. These waves bounce off the prostate and the echoes are received by a computer to create a sonogram (UCSF Medical Center 2007), which can be used to detect abnormal areas in the prostate or for guiding transrectal biopsy (Taneja 2004.) Color Flow Doppler/Power Doppler- theoretically, when compared to grayscale ultrasound, color flow Doppler can identify isoechoic cancers. It can also show the blood flow characteristics, which allows to distinguish malignant from benign lesions within hypoechoic areas. Power Doppler is 3 to 4 times more sensitive than color Doppler for areas of increased flow (Taneja 2004.) MRI-MRI (magnetic resonance imaging) is a procedure for obtaining a series of detailed images of the body using a magnet, radio waves, and a computer (National Cancer Institute n.d). A better visualization of the zonal anatomy of prostate, as well as the location and extent of tumor can be obtained by the use of an endorectal coil (magnetic coil placed directly into the rectum ) MRI. Magnetic Resonance Spectroscopy (MRSI) “is an MRI technique that attempts to identify cancer through the assessment of tissue metabolites” (Taneja 2004). By using a strong magnetic field, MRSI obtains metabolic information (spectra). This helps to identify the relative concentrations of various metabolites in the cell cytoplasm and the extracellular space. This technique can identify metabolic differences in prostate tissue (BPH, prostate cancer, and normal prostate tissue) (Carroll et al 2006) Imaging for the staging of prostate cancer-some imaging modalities are used in the staging of prostate cancer. An accurate staging helps to maximize treatment efficacy (Taneja 2004). Staging can be divided into local staging, in order to identify extracapsular extension, and distant staging, in order to identify metastases to lymph nodes and bone (Taneja 2004.) 1. Distant staging a. Radionuclide bone scan-involves the injection of a radioactive material in to the blood, which is then detected in the bone with a scanner (National Cancer Institute n.d). The usual isotope, which is used is Technetium 99m (99mT)-labeled diphosphonate (Taneja 2004.) b. Computerized tomography (CT)-this involves taking a series of pictures from different angles of the body, which is interpreted by a computer to produce an image. CT scan is used in prostate cancer to identify abnormally enlarged lymph nodes. In order to define larger foci of metastatic disease in the lymph nodes, a 3-D MRI reconstructed T1-weighted images can be used (Taneja 2004.) 2. Local Staging- Imaging utilized for pre-operative assessment of disease stage include: TRUS and MRI/MRSI (Taneja 2004.) Treatment 1. Surgery: a. Pelvic lymphadenectomy: this surgery involves the removal of pelvic lymph nodes, and visualization of the nodes under a microscope by the pathologist for malignant cells. If the lymph nodes are negative for malignant cells, the prostate is not removed and other treatment modalities are used (National Cancer Institute n.d) b. Radical prostatectomy: this surgery involves the removal of the prostate, surrounding tissue, and seminal vesicles. Two types of radical prostatectomy may be done: retropubic prostatectomy, in which the prostate is removed through an abdominal wall incision along with removal of adjacent lymph nodes (National Cancer Institute n.d), and perineal prostatectomy, which involves the removal of the prostate through an incision in the perineum along with removal of adjacent lymph nodes (National Cancer Institute n.d). c. Transurethral resection of the prostate (TURP): this surgery involves the removal of the prostate with a resectoscope inserted through the urethra (National Cancer Institute n.d) 2. Radiation therapy-here, high-energy x-rays are used to destroy the malignant cells. Radiation therapy is of two types: external radiation therapy and internal radiation therapy. External radiation therapy involves the use of a machine external to the body, to send radiation toward the cancer. In internal radiation therapy, needles, seeds, wires, or catheters containing a radioactive substance, is directly placed into or near the cancer (National Cancer Institute n.d). For low, intermediate, and high-risk patients, low-dose rate brachytherapy can be used. High-dose-rate brachytherapy, used alone or in combination with external-beam radiotherapy can be beneficial in patients with localized prostate cancer (Koukourakis et al 2009). 3. Hormone therapy-male sex hormones produced normally by the body can make the prostate cancer grow. Hormone therapy thus involves the use of drugs (ketoconazole, aminoglutethimide, and antiandrogens- flutamide and nilutamide), surgery (orchiectomy), or other hormones (luteinizing hormone-releasing hormone agonists-leuprolide, goserelin, estrogens) to either block the male sex hormones or reduce their production (National Cancer Institute n.d) 4. New types of treatment a. Cryosurgery-Cryosurgery or cryotherapy is the use of an instrument to freeze and destroy prostate cancer cells (National Cancer Institute n.d). Cryotherapy is a potential alternative to standard therapies for the primary treatment of localized prostate cancer (Shelley et al 2007.) b. Chemotherapy-this type of treatment uses drugs, which either kills the cancer cells or stops them from dividing, and therefore, stops the growth of cancer cells (National Cancer Institute n.d) c. Biologic therapy- also known as biotherapy or immunotherapy, involves the use of the patient’s own immune system with either substances made by the body or made in a laboratory to fight cancer (National Cancer Institute n.d) d. High-intensity focused ultrasound-this type of treatment uses ultrasound (high-energy sound waves) to destroy cancer cells. In prostate cancer, the sound waves are created by an endorectal probe (National Cancer Institute n.d) Prognosis of prostate cancer In general, the prognosis for the majority of patients with prostate cancer (localized or regional) is very good. Depending on their age and comorbidities, the life expectancy for elderly men with prostate cancer varies. A long-term local control, or even cure, is possible in many patients but depends on the staging and grade of the tumor (The Merck Manuals, 2009.) If treatment is delayed, a poor prognosis is given for patients with high-grade, poorly differentiated cancer. The response to conventional therapy is poor in undifferentiated prostate cancer, squamous cell carcinoma, and ductal transitional carcinoma. There is no cure for metastatic cancer, and the median life expectancy with metastatic disease is 1 to 3 years (The Merck Manuals, 2009.) Conclusion The clinical examination and tests for a patient with prostate cancer includes: urinalysis, digital rectal examination, and measurement of blood prostate-specific antigen (PSA) levels. The majority of prostate cancers (95%) are adenocarcinomas and about 70% of prostate cancers arise in the peripheral zone. They can be locally invasive, and early metastasis to the bone and distant metastases to the liver, lungs, and adrenal glands etc can occur. The imaging modalities employed in the diagnosis of prostate cancer includes the use of transrectal ultrasound (TRUS), color flow Doppler, power Doppler, MRI and MRSI. Some imaging modalities are used in the staging of prostate cancer, and these include: radionuclide bone scan, computerized tomography (CT), TRUS and MRI/MRSI. The surgical treatment for prostate cancer includes: pelvic lymphadenectomy, radical prostatectomy, and transurethral resection of the prostate (TURP). The other treatment modalities used are radiation therapy and hormone therapy. The newer types of treatment for prostate cancer includes: cryosurgery, chemotherapy, biologic therapy, and high-intensity focused ultrasound. In general, the prognosis for the majority of patients with prostate cancer is very good. There is no cure for metastatic cancer. References BCM. Prostate cancer and fibroblast growth factors. http://www.bcm.edu/pathology/labs/Ittmann/overview.htm Carroll, PR, Coakley, FV and J. Kurhanewicz 2006. Magnetic Resonance Imaging and Spectroscopy of Prostate Cancer. Rev Urol. 8(Suppl 1): S4–S10. Hammerich, KH, Ayala, GE and TM. Wheeler, n.d. Anatomy of the prostate gland and surgical pathology of prostate cancer. Cambridge University Press. www.cambridge.org. Koukourakis G, Kelekis N, Armonis V and V. Kouloulias. 2009. Brachytherapy for prostate cancer: a systematic review. Adv Urol. Malecare. Prostate. http://www.malecare.com/prostate-cancer_42.htm National Cancer Institute n.d. Prostate cancer treatment. http://www.cancer.gov/cancertopics/pdq/treatment/prostate/Patient/page2. Radiology. CT prostate cancer. www. radiology.rsnajnls.org/.../full/243/1/28/F4 RadiologyInfo. MRI of prostate. http://www.radiologyinfo.org/en/info.cfm?pg=mr_prostate Radiographics. Anatomy of prostate. www. radiographics.rsnajnls.org/.../full/23/4/951/F3A Shelley M, Wilt TJ, Coles B and M.D. Mason. 2007. Cryotherapy for localised prostate cancer. Cochrane Database Syst Rev. Taneja, SS. 2004. Imaging in the Diagnosis and Management of Prostate Cancer. Rev Urol. 6(3): 101–113. Theodorescu, D and T.L. Krupski. 2009. Prostate Cancer - Biology, Diagnosis, Pathology, Staging, and Natural History. Emedicine. http://emedicine.medscape.com/article/458011-overview. The Merck Manuals. 2009. Prostate cancer. http://www.merck.com/mmpe/sec17/ch241/ch241e.html UCSF Medical Center. 2007. Prostate cancer. http://www.ucsfhealth.org/adult/medical_services/cancer/urologic/conditions/prostate/diagnosis.html. UCSF Medical Center. 2007. MRI prostate cancer. www.ucsf.edu/multimedia/photography/details/67/ Read More