Adenocarcinoma of the prostate is histologically the commonest form of prostate malignancy. It is often asymptomatic until advanced or metastatic disease leads to symptoms of obstructive uropathy or bone pain respectively. Diagnosis depends upon digital rectal palpation, levels of prostate-specific antigen and prostate biopsy.
Presentation
Prostate cancer ranks the fifth in the list of the common causes of death in men suffering from cancer [1] [2]. The most prevalent histological form of prostate malignancy is an adenocarcinoma [3] [4]. Although widespread globally, it's incidence is high among the males of African descent in the United States [5].
Screening tests currently help to diagnose adenocarcinoma of the prostate before the onset of symptoms [6]. In addition, it is often asymptomatic as it grows slowly. Symptoms typically appear in advanced stages either due to urinary obstruction or metastasis. The main symptoms include increased frequency of urination, urinary hesitancy, weak urine stream, nocturia, urinary urgency, and hematuria. Renal dysfunction secondary to urinary obstruction or enlarged retroperitoneal lymph nodes may also be a presenting manifestation.
Symptoms like anorexia, loss of weight, backache, pain in the lower limbs, pain in the bones, and pathological bone fractures may be seen in some cases due to bone metastasis.
Workup
The workup of adenocarcinoma of the prostate commences with a detailed history and a digital rectal examination (DRE). Palpation of nodules or induration on DRE could indicate malignancy or prostatitis with seminal vesicle induration and restricted mobility of the prostate being suggestive of advanced prostate malignancy.
Laboratory tests like a complete blood count, renal function tests, acid phosphatase levels and prostate-specific antigen (PSA) levels are performed in all patients. PSA is a tumor marker [7] [8] [9] [10] [11] [12] [13] and high baseline levels are suggestive of a current or future likelihood of metastasis but it does not predict the risk of the disease. Elevated acid phosphatase levels are an indicator of poor prognosis although its levels could also be elevated after a prostate massage, in benign prostate hypertrophy (BPH) and some other disorders.
Confirmation of the diagnosis requires a biopsy with histology. The biopsy is typically obtained through an ultrasound directed transrectal approach. Multiple biopsies are taken from different sites and this helps to detect malignancy in patients with an elevated PSA level [6]. An ultrasound guided transperineal biopsy is preferred in patients in whom transrectal biopsy is likely to be associated with complications [14]. The Gleason score is used to define the histological differentiation of the tumor in the biopsy specimen [15] and is an indicator of tumor aggressiveness [16]. Well-differentiated tumors usually have a score less than or equal to six; moderately differentiated tumors have a score of 7 while poorly differentiated tumors are scored 8 -10.
Imaging studies like transrectal ultrasonography (TRUS), computed tomography (CT) scan, magnetic resonance imaging (MRI) and bone scan are used to detect local and distant spread and for staging adenocarcinoma of the prostate. Indium-111 capromab pendetide scanning and reverse transcriptase - polymerase chain reaction (PCR) assays for circulating prostate cancer cells are being studied as potential tools for staging and prognosis.
Treatment
Treatment options for adenocarcinoma of the prostate depend on the stage and grade of the cancer, as well as the patient's overall health and preferences. Options may include active surveillance for low-risk cases, surgery (prostatectomy), radiation therapy, hormone therapy, chemotherapy, and newer treatments like immunotherapy. Each treatment has its own risks and benefits, which should be discussed thoroughly with the patient.
Prognosis
The prognosis for prostate cancer varies widely based on the stage at diagnosis and the cancer's aggressiveness. Early-stage prostate cancer has a very high survival rate, with many patients living for many years after diagnosis. Advanced prostate cancer, which has spread beyond the prostate, has a less favorable prognosis but can often be managed with treatment to improve quality of life and extend survival.
Etiology
The exact cause of prostate cancer is not known, but several risk factors have been identified. These include age (most common in men over 65), family history of prostate cancer, race (more common in African American men), and certain genetic mutations. Lifestyle factors such as diet and obesity may also play a role.
Epidemiology
Prostate cancer is one of the most common cancers in men worldwide. It is particularly prevalent in Western countries, with varying incidence rates across different regions. The risk of developing prostate cancer increases with age, and it is more common in African American men compared to men of other races.
Pathophysiology
Adenocarcinoma of the prostate develops when the glandular cells of the prostate undergo genetic mutations that lead to uncontrolled cell growth. These cancerous cells can invade nearby tissues and spread to other parts of the body, such as the bones and lymph nodes, through a process called metastasis.
Prevention
While there is no sure way to prevent prostate cancer, certain lifestyle changes may reduce the risk. These include maintaining a healthy diet rich in fruits and vegetables, regular physical activity, and maintaining a healthy weight. Some studies suggest that certain medications may lower the risk, but these should only be considered after discussing with a healthcare provider.
Summary
Adenocarcinoma of the prostate is a common type of cancer in men, characterized by the uncontrolled growth of glandular cells in the prostate. Early detection through screening can lead to effective management and a favorable prognosis. Treatment options vary based on the stage and aggressiveness of the cancer, and lifestyle changes may help reduce the risk.
Patient Information
If you or someone you know is experiencing symptoms such as difficulty urinating or persistent pain in the pelvic area, it is important to consult a healthcare provider. Early detection of prostate cancer can significantly improve treatment outcomes. Regular check-ups and discussions about prostate health with your doctor are key components of maintaining overall well-being.
References
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