Prostate Cancer

Overview and Pathophysiology of Prostate Cancer

• General Statistics and Impact:

  • Cancer is identified as the second leading cause of death among men.

  • Incidence is primarily noted in men older than $65\,\text{years old}$.

  • Survival Rate: Even when the cancer has metastasized (spread), $98\%$ of patients are alive after $5\,\text{years}$.

• Anatomy and Cell Composition:

  • The prostate consists primarily of glandular epithelial cells.

  • Androgens: These male hormones are believed to have a significant role in the development/progression of prostate cancer.

  • Adenocarcinomas: This is the primary classification for most prostate cancers.

• Tumor Progression and Anatomical Barriers:

  • Metastasis Barrier: Despite the prostate's proximity to the rectum, metastasis to the bowel is uncommon because the "rectoprostatic fascia" acts as an effective physical barrier.

  • Urethral Compression: As the tumor enlarges, it may compress the urethra, resulting in the obstruction of urinary flow.

Etiology and Genetic Factors

• Basic Etiology: The cancer originates from changes in the DNA of a normal prostate cell.

• Genetic Risk Factors: Men possessing specific genes have an increased risk of developing prostate cancer. These include:

  • RNASFL

  • BRCA 1

  • BRCA 2

  • MS2

  • MLH1

  • HOXB13

Risk Factors and Prevention

• Core Risk Factors:

  • Age: Specifically men who are $70\,\text{years old}$ and older.

  • Race: Higher incidence in African American men.

  • Diet: Factors include diets high in dairy food, processed meat, animal fat, and excessive supplemental Vitamin A.

  • Obesity.

  • Occupation: Firefighters are cited as a specific high-risk group.

  • Heredity: Genetic/familial factors.

  • Vasectomy: Identified as a factor because it prevents ejaculation.

• Preventative Pharmaceutical Interventions:

  • Drugs: Dutasteride and Finasteride involve reducing the amount of male hormones.

  • Side Effects of Prevention Drugs: These medications may cause decreased libido and ejaculation issues.

Screening Guidelines

Screening involves informed decision-making based on risk levels and life expectancy (minimum $10\,\text{years}$ required for screening to be initiated):

• Average Risk: Screening should initiate at $50\,\text{years old}$.

• High Risk: This group includes African American men and those with a close relative diagnosed; screening should begin at $45\,\text{years old}$.

• Even Higher Risk: This group includes men who have several close relatives diagnosed with prostate cancer at an early age; screening should begin at $40\,\text{years old}$.

Clinical Manifestations and Symptomatology

• Early Stage: Characterized by showing no clinical manifestations whatsoever.

• Initial Signs of Metastasis: Pain resulting from metastasis to the bones is often the initial symptom noted.

• Urinary Symptoms:

  • Urgency.

  • Frequency.

  • Dysuria (painful urination).

  • Nocturia (frequent nighttime urination).

  • Hesitancy: Defined as delay, slowness, or difficulty in starting the action of urination.

  • Hematuria (blood in the urine) and blood.

• Pain Locations and Bone Involvement:

  • Cancer metastasizing to bones causes bone or joint pain specifically in the hips, thighs, or shoulders.

  • Back pain.

  • Pathological Fracture: Fractures caused by disease/weakening of the bone rather than trauma.

Diagnostic Procedures

• Definitive Diagnosis: Obtained through a biopsy of the prostate tissue.

• Digital Rectal Exam (DRE):

  • The examiner feels the prostate for abnormalities.

  • If cancer is present, the prostate may feel nodular (lumpy) and fixed.

• Prostate-Specific Antigen (PSA) Test:

  • Function: Used for screening and monitoring the response to treatment.

  • Levels and Age: PSA levels generally increase as a man ages because the prostate naturally enlarges.

  • Thresholds: While higher levels are concerning, some men with prostate cancer still have PSA levels below $4.0\,ng/mL$.

  • False Elevations: High PSA results can be caused by prostatitis, urinary tract infections (UTIs), certain medications, or herbal supplements.

• Definitions and Other Exams:

  • Prostatitis: Defined as inflammation of the prostate.

  • Transrectal Ultrasonography (TRUS): Used when the DRE is abnormal or the PSA is elevated. A probe is inserted into the rectum to create images and help guide the needle biopsy.

  • Imaging and Analysis: Urinalysis, Cystoscopy, Bone scan, MRI, and CT scan.

  • Purpose of Imaging: Specifically used to determine whether the cancer has metastasized.

Grading and Staging

• Grade: Describes the level of differentiation in the cancer cells.

• Stage: Describes the extent of cancer spread and is the primary tool for guiding treatment decisions.

• Stage I:

  • The cancer is confined within the prostate.

  • Nonpalpable (cannot be felt during a DRE).

  • Involves a small, localized area.

  • Well-differentiated cells.

• Stage II:

  • Still confined to the prostate.

  • Palpable (can be felt during a DRE).

  • Involves one or both lobes of the prostate.

  • More poorly differentiated cells.

• Stage III:

  • The cancer has extended outside the prostate capsule.

  • May involve the seminal vesicles.

• Stage IV:

  • The cancer has spread into surrounding tissues.

  • May involve regional lymph nodes.

  • May have distant metastases, most commonly to the bone.

Surgical Treatments

• TURP (Transurethral Resection of the Prostate):

  • Part of the prostate is removed through the urethra using an instrument inserted via the penis.

  • May cure very early prostate cancer in some older men.

  • Note: TURP is not typically given for advanced disease.

• Radical Prostatectomy:

  • Full removal of the prostate gland, prostate capsule, seminal vesicles, and part of the bladder neck.

  • Possible Complications: Erectile dysfunction, urinary incontinence, urethral stricture, fistula, and rectal injury.

• Laparoscopic Radical Prostatectomy:

  • A minimally invasive version of the radical prostatectomy.

  • Conducted through small abdominal incisions using a laparoscope.

• Retropubic Prostatectomy:

  • A surgical approach through the lower abdomen.

  • Advantages: Better control of bleeding, clear visualization of the prostate bed/bladder neck, and easy access to pelvic lymph nodes.

  • Status: Generally the most commonly favored surgical approach.

• Perineal Prostatectomy:

  • Approach through the perineum (area between the scrotum and anus).

  • Preferred for older adults or poor surgical candidates.

  • Requires less surgical time and causes less bleeding.

• Suprapubic Prostatectomy:

  • Approach through the bladder. Rarely used.

  • May be chosen if specific bladder problems are expected.

  • Disadvantage: Bleeding is more difficult to control.

• Surgery Eligibility and Considerations:

  • Surgery is not ideal for Stage III because of the likelihood of hidden lymph nodes and metastasis.

Artificial Urinary Sphincter

• This device is surgically implanted to manage incontinence.

• Patient Eligibility Requirements:

  • The patient must possess the manual dexterity to manipulate the pump located in the scrotum.

  • The patient must have adequate cognitive function to understand device operation and recognize problems.

Radiation Therapy

• Can be used as a primary treatment.

• Carries a lower risk of long-term impotence and urinary incontinence compared to surgery.

• External-beam radiation therapy (EBRT): Radiation is directed at the prostate from outside the body.

• Brachytherapy: Implantation of radioactive seeds directly into the prostate (also called interstitial radiation).

  • Contains a lower risk of rectal damage and impotence compared to EBRT.

• Palliative Therapy: Radiation used for metastatic cancer to reduce bone metastasis size, control pain, and improve functions like continence.

Vitamin Supplements and Clinical Research

• General Warning: Natural and over-the-counter supplements are not inherently safe.

• SELECT Study Findings:

  • Selenium and Vitamin E supplements did not reduce the risk of prostate cancer.

  • Vitamin E Danger: Vitamin E supplements were actually associated with an increased risk of developing prostate cancer.

• Ongoing Research: Scientists are currently studying whether soy proteins may help reduce cancer risk.

• Nursing Role: Nurses must assess patients' use of all supplements and nonprescription therapies. Patients must consult providers before starting any complementary therapy.