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Prostate cancer: Difference between revisions
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(Created page with "<section begin="pathology" /><section begin="oncology" />'''Prostate cancer''' is the most common form of cancer in men, accounting for around 25% of cases. However, it causes only 9% of all cancer deaths, which shows that it has a low mortality. This is owed mostly to regular screening of PSA levels and digital rectal examination. Prostate cancer is mostly a disease of elderly. About 1 in 8 men will be diagnosed with prostate cancer at some point of their lives, but aut...") |
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<section begin="pathology" /><section begin="oncology" />'''Prostate cancer''' is the most common form of cancer in men, accounting for around 25% of cases. However, it causes only 9% of all cancer deaths, which shows that it has a low mortality. This is owed mostly to regular screening of PSA levels and digital rectal examination. Prostate cancer is mostly a disease of elderly. About 1 in 8 men will be diagnosed with prostate cancer at some point of their lives, but autopsy studies have shown that many more than this actually develop prostate cancer, but that it remains too small to be significant. | <section begin="urology" /><section begin="pathology" /><section begin="oncology" />'''Prostate cancer''' is the most common form of cancer in men, accounting for around 25% of cases. However, it causes only 9% of all cancer deaths, which shows that it has a low mortality. This is owed mostly to regular screening of PSA levels and digital rectal examination and that we have relatively effective treatment. Prostate cancer is mostly a disease of elderly. About 1 in 8 men will be diagnosed with prostate cancer at some point of their lives, but autopsy studies have shown that many more than this actually develop prostate cancer, but that it remains too small to be significant. | ||
Management may involve local radiotherapy, radical prostatectomy, or "active surveillance" (giving no treatment but monitoring closely for progression). Prostate cancer is usually not aggressive and has a good prognosis, which allows for the watchful waiting approach. A commonly known saying is that "more men die with prostate cancer than because of it". | Management may involve local radiotherapy, radical prostatectomy, or "active surveillance" (giving no treatment but monitoring closely for progression). Prostate cancer is usually not aggressive and has a good prognosis, which allows for the watchful waiting approach. A commonly known saying is that "more men die with prostate cancer than because of it". | ||
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* Age > 50 years | * Age > 50 years | ||
* Positive family history | * Positive family history | ||
* African-American | * African-American ethnicity | ||
* Scandinavian | * Scandinavian ethnicity | ||
* Obesity | * Obesity | ||
* Diet high in animal fat | * Diet high in animal fat | ||
Benign prostatic hyperplasia is ''not'' a risk factor for prostate cancer. | |||
Importantly, because the peripheral zone is not removed during simple prostatectomy or TUR-P, prostate cancer can still develop after these procedures (which are used for BPH). | |||
== Pathology == | == Pathology == | ||
95% of prostate cancers are acinar adenocarcinomas. The cells of the cancerous prostatic glands have prominent nucleoli and show atypia. These glands are small and are also not surrounded by basal cells, unlike the healthy prostatic glands. Prostate cancer has a long doubling time.<section end="oncology" /> | 95% of prostate cancers are acinar adenocarcinomas, the remaining neuroendocrine tumours and sarcomas. Adenocarcinomas develop from the peripheral zone. The cells of the cancerous prostatic glands have prominent nucleoli and show atypia. These glands are small and are also not surrounded by basal cells, unlike the healthy prostatic glands. Prostate cancer has a long doubling time.<section end="oncology" /> | ||
Prostate cancer, like BPH, depends heavily on androgens. Most cases of prostate cancer regress temporarily after anti-androgen therapy. This often leads to the cancer developing a mutation that allows it to function even in the absence of androgens. | Prostate cancer, like BPH, depends heavily on androgens. Most cases of prostate cancer regress temporarily after anti-androgen therapy. This often leads to the cancer developing a mutation that allows it to function even in the absence of androgens.<section end="urology" /> | ||
Fusion of the genes TMPRSS2 and ETS occurs in 50% of prostate cancers. Inactivating mutations of the tumor suppressor PTEN is also frequent. | Fusion of the genes TMPRSS2 and ETS occurs in 50% of prostate cancers. Inactivating mutations of the tumor suppressor PTEN is also frequent.<section begin="oncology" /><section begin="urology" /> | ||
<section begin="oncology" /> | |||
=== Metastasis === | === Metastasis === | ||
Prostate cancer is relatively indolent, generally not metastasising often. When it does, metastasis to bone and liver are most common. | Prostate cancer is relatively indolent, generally not metastasising often. When it does, metastasis to bone and liver are most common. | ||
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<section begin="oncology" /> | <section begin="oncology" /> | ||
== Clinical features == | == Clinical features == | ||
Prostate cancer usually | Prostate cancer usually does not cause symptoms in the early stages. As most (70 – 80%) prostate cancer grows in the peripheral zone of the prostate, lower urinary tract symptoms are rarely seen until the later stages, when the cancer has grown. Advanced-stage prostate cancer may present with general cancer symptoms like fatigue and loss of appetite. | ||
Prostate cancer most frequently metastasizes into the spine, especially the lumbosacral part, causing lower back pain. It also metastasizes to parailiac lymph nodes. | Prostate cancer most frequently metastasizes into the spine, especially the lumbosacral part, causing lower back pain. It also metastasizes to parailiac lymph nodes. | ||
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Multiparametric [[MRI]] (mp-MRI) is a form of MRI which combines multiple MRI modalities to assess the prostate for cancer better than a "regular" MRI can. | Multiparametric [[MRI]] (mp-MRI) is a form of MRI which combines multiple MRI modalities to assess the prostate for cancer better than a "regular" MRI can. | ||
Transrectal ultrasound may be used in the evaluation of prostate cancer. | Transrectal ultrasound may be used in the evaluation of prostate cancer to calculate the prostate volume and to guide biopsy.<section begin="pathology" /> | ||
<section begin="pathology" /> | |||
=== PSA === | === PSA === | ||
''Main article:'' [[PSA]] | ''Main article:'' [[PSA]] | ||
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In addition to measuring the total level of PSA, one can also measure other parametres such as free PSA, PSA density, PSA velocity, complexed PSA, and percentage of [-2]proPSA (a precursor of PSA). While decreased free PSA is known to be more specific for prostate cancer than total PSA, the clinical utility of the other parametres is not yet established and so they're not much used. | In addition to measuring the total level of PSA, one can also measure other parametres such as free PSA, PSA density, PSA velocity, complexed PSA, and percentage of [-2]proPSA (a precursor of PSA). While decreased free PSA is known to be more specific for prostate cancer than total PSA, the clinical utility of the other parametres is not yet established and so they're not much used. | ||
=== Staging === | |||
* T1 – incidental finding | |||
** Not palpable or visible on imaging | |||
** Present biochemically (as elevated PSA) | |||
* T2 – localized cancer | |||
** Localized to prostate | |||
* T3, T4 – locally advanced cancer | |||
* N+ or M+ – metastatic cancer | |||
<section end="urology" /><section begin="urology treatment" /> | |||
== Treatment == | == Treatment == | ||
In many cases of prostate cancer an “active surveillance” approach might be safer than outright treating the tumor. This is especially true for elderly people with comorbidities or people with a less than 10-year life expectancy, as the treatment might be worse than the disease. | In many cases of prostate cancer an “active surveillance” approach might be safer than outright treating the tumor. This is especially true for elderly people with comorbidities or people with a less than 10-year life expectancy, as the treatment might be worse than the disease. | ||
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The efficacy of screening for prostate cancer is debated. The reason for this is that not all cases of prostate cancer are aggressive and fatal; many cases follow a very indolent course with few clinical symptoms. Screening (especially with PSA) can’t differentiate between prostate cancers that would become aggressive and those that wouldn’t, and so many people who would develop clinically indolent prostate cancer undergoes potentially life-changing treatment which may be worse than the symptoms of the cancer would have been. Indeed, prostate cancer is often found incidentally on autopsy, and more people die with prostate cancer than of prostate cancer. | The efficacy of screening for prostate cancer is debated. The reason for this is that not all cases of prostate cancer are aggressive and fatal; many cases follow a very indolent course with few clinical symptoms. Screening (especially with PSA) can’t differentiate between prostate cancers that would become aggressive and those that wouldn’t, and so many people who would develop clinically indolent prostate cancer undergoes potentially life-changing treatment which may be worse than the symptoms of the cancer would have been. Indeed, prostate cancer is often found incidentally on autopsy, and more people die with prostate cancer than of prostate cancer. | ||
In Norway, there is no national screening programme for prostate cancer. In Hungary, the lecture recommends annual DRE and PSA measurement for men older than 50, but there is no national screening programme (as far as I can see).<section end="oncology" /> | In Norway, there is no national screening programme for prostate cancer. In Hungary, the lecture recommends annual DRE and PSA measurement for men older than 50, but there is no national screening programme (as far as I can see).<section end="oncology" /><section end="urology treatment" /> | ||
[[Category:Oncology]] | [[Category:Oncology]] | ||
[[Category:Urology]] | [[Category:Urology]] | ||