PSA Levels and Testing Explained

Prostate-specific antigen (PSA)

这prostate glandis commonly described as “walnut-shaped,” and is located behind the bladder and in front of the rectum. It surrounds the urethra, the tube which passes urine and semen out of the body.

这prostate gland makes a protein called prostate-specific antigen, or PSA. A healthy person’s prostate should circulate a small amount of PSA in their blood.

Factors affecting PSA

与前列腺有关的几个健康因素和条件可能导致腺体产生更多的PSA。

这se include:

• 前列腺炎。这是指的 inflammation and swelling 在腺体和周边地区，往往是由于细菌感染。前列腺炎可能非常痛苦。
• 良性前列腺增生症。一种lso called prostate enlargement, this condition can cause frequent and strained urination, and increased urination at night, among other symptoms. It is 不癌变 。
• 前列腺癌。This occurs when malignant cells 不可控制地生长 in the prostate’s tissues. The gland swells, and isn’t able to function properly. In rare instances, prostate cancer can spread elsewhere in the body. In general, a higher PSA level indicates 更高的机会 前列腺癌。
• Urinary tract infection (UTI).Most尿路感染是由细菌引起的。他们可以在前列腺中的其他健康问题旁边发生。发现了2020年的研究 34.6 percent 前列腺癌患者经历过utis。

某些药物实际上可以降低PSA作为副作用。这可能会干扰前列腺癌筛查和PSA水平测试的准确性。

一种2010 study成立nonsteroidal anti-inflammatory drugs(such as Aleve and Advil),statins(drugs that lower cholesterol) andthiazide diuretics(which treat high blood pressure) had a statistically significant impact on PSA levels when taken long term.

Finasterideanddutasteride，常用药物治疗男性模式脱发和扩大前列腺的药物， also cause reduction in PSA levels.

PSA level test

这level of PSA in your blood can be checked with a simple blood test. A nurse or healthcare worker will draw blood, usually from a vein in your arm, using a needle. The blood is then sent to a lab for analysis.

PSA测试只有一个工具决定是否需要进一步测试。只有A.组织活组织检查可以明确地诊断癌症。

诊断前列腺癌

如果您的医生认为您的PSA测试结果需要进一步调查，它们可能会使前列腺组织活检作为下一步。

During this biopsy, your doctor will use a thin needle to take a small sample of tissue from your prostate to be analyzed. This can show the presence of malignant cells.UltrasoundandMRItechnology may be used to guide a biopsy.

Learn more about the process of getting a prostate biopsy

高psa水平是什么意思？

这re is no universal scale for judging PSA levels. Results are usually given in nanograms of PSA per milliliter of blood (ng/mL). According to 这National Cancer Institute 那a measurement of 4 ng/mL or below used to be marked “normal.” A higher PSA result was seen as irregular, indicating need for prostate biopsy.

However, scientists found this method wasn’t totally reliable. Some men with higher PSA levels have healthy prostates, and some with regular PSA levels can have cancer. This is why PSA level testing is not a perfect method for detecting and diagnosing prostate cancer. But it is an important tool.

Checking PSA levels regularly can help establish a personal baseline. If levels rise over time, this can indicate need for further screening. Repeat testing may also be done if prostatitis is suspected.

If you’re already diagnosed with prostate cancer, regular PSA level testing can track your disease progression, and response to treatment.

Staging prostate cancer

将前列腺癌组织成阶段进行，以传达沿着疾病的程度，并帮助计划治疗。阶段的范围为1至4，具有较高的数字，表明疾病更高。

Prostate cancer, like many other cancers, is described based on the一种merican Joint Committee on Cancer'TMN（肿瘤，转移，节点）分期系统。该分期系统基于肿瘤的大小或程度，所涉及的淋巴结的数量，以及癌症是否已经向远处部位或器官传播或转移。

这cancer’s stage is further determined based on two additional factors: the PSA level andthe Gleason scale。

这role of PSA in staging

Prostate cancer causes cells to become malignant and multiply uncontrollably. This can lead to overproduction of PSA, and higher levels of PSA in the bloodstream.

However, some men who have prostate cancer do not exhibit elevated PSA levels. And certain noncancerous conditions, like a prostate infection or benign enlargement, can also cause high PSA levels.

PSA levels are just one factor used in determining the stage of prostate cancer. Another diagnostic tool is called the Gleason scale. This rates the extent of abnormality in your prostate cells after biopsy.

一种t a certain point in prostate cancer’s late-stage progression, Gleason and PSA become less useful. When a tumor is large enough, doctors no longer need these numbers to predict its growth or malignancy.

Overview of stages

以下是每种前列腺癌症阶段的崩溃 AJCC的系统 。This table shows common symptoms at each stage 那and what PSA levels are typically identified:

Treatment

你的医生将重量 multiple factors 考虑到前列腺癌的任何给定治疗是您的最佳选择。

这se include:

• cancer severity
• 预期寿命
• impacts on your quality of life
• 您的整体功能，以及任何共存健康状况
• whether other treatments have been or should be tried first

如果癌症相对局部（限于前​​列腺的一个区域），可以用：

• 观察和监测
• 前列腺切除术（移除of partor所有的前列腺的）
• radiation therapy(using special X-rays to kill cancer cells 的）
• 其他药物治疗症状

Should your prostate cancer become more widespread, your doctor may also recommend hormone treatment. This is also calledandrogen deprivation therapy (ADT)。

一种DT can be very effective at slowing or stopping cancer growth, but it can cause side effects including较低的性欲那勃起功能障碍（ED）和疲劳。此外，一些癌症不要回应ADT。

Patients who are generally in good health and expected to be functional post-treatment will likely be offered surgery. However, if disease is widespread, extending past the prostate to other tissues and organs, surgery may no longer be an option.

Who should get screened for prostate cancer?

PSA水平测试有时可以导致前列腺癌的“假阳性”。这可能导致不必要的侵入性程序，并在低风险中产生对癌症的压力。

这2018U.S. Preventive Services Task Force得出以下结论：

• Men aged 55 to 69 should decide for themselves whether to undergo a PSA level blood test, after talking it over with their doctor.
• For men over age 70, the potential risks of PSA screening outweigh the benefits.
• 这re isn’t conclusive evidence yet that PSA screening prevents prostate cancer deaths.

这 CDC explains that older men, Black men, and men with a history of prostate cancer in their family are most at risk of developing it.这majority of cases are diagnosed in men 超过65岁 。

Outlook

Prostate cancer is one of the most common types of cancer. Statistics from 2016-2018 show that around 12.5％的美国人 将在终生中诊断出来。

多种诊断工具一起用于筛选和诊断前列腺癌。这包括PSA水平测试，前列腺组织活检和成像。这些工具还用于监测疾病进展，以及如何响应治疗。

前列腺癌有一个非常积极的前景，特别是在最后阶段之前捕获。治疗方案迅速进行，所有类型的前列腺癌的五年生存率是 97.5％ 。

Talk to your doctor about your risk factors, and to learn more about the pros and cons of PSA level testing.