Prostate cancer

What it is

Prostate cancer is a cancer of the prostate gland, and about 95% of cases are adenocarcinomas. The prostate is a small gland below the bladder that helps make semen. Most prostate cancers grow from the gland-forming cells of the prostate, which is why they are called adenocarcinomas. A key fact for patients is that many prostate cancers grow slowly, but some are aggressive and can spread, especially to lymph nodes and bone.

Prostate cancer is one of the most common cancers in men worldwide. Risk rises strongly with age, and many people have no symptoms in the early stages. When symptoms do occur, they can overlap with common non-cancer conditions such as benign prostatic hyperplasia, so testing is needed to tell the difference. In India, awareness is increasing as life expectancy rises and more men undergo PSA testing and specialist evaluation, but screening and treatment decisions are still individualised rather than one-size-fits-all.

A simple way to think about prostate cancer is by risk group and stage:

Feature	What it means
Localised	Cancer appears confined to the prostate
Locally advanced	Cancer has grown just outside the prostate or into nearby structures
Metastatic	Cancer has spread to distant sites, commonly bone
Low-risk	Usually slower-growing disease, often suitable for active surveillance
Intermediate/high-risk	Higher chance of growth or spread, often needs active treatment

How it works

Prostate cancer starts when prostate cells develop DNA changes that let them grow and survive when they should not. Over time, these abnormal cells can form a tumour, invade nearby tissue, and in some cases spread through lymphatic channels or the bloodstream.

Hormone signaling is central to this cancer. Many prostate cancer cells depend on androgens, especially testosterone and dihydrotestosterone, to grow. That is why androgen deprivation therapy, which lowers androgen levels or blocks androgen signaling, is a major treatment for advanced disease.

Doctors also describe prostate cancer by grade. On biopsy, the pathologist looks at how abnormal the cancer cells appear and how they are arranged. This is summarised in the Gleason score or Grade Group system. In general, a higher grade means the cancer is more likely to grow and spread.

Important factors that influence behavior include:

1. PSA level: Higher levels can suggest more cancer activity, though PSA is not specific for cancer.
2. Grade Group/Gleason score: Higher grade usually means more aggressive disease.
3. Tumour stage: Whether the cancer is confined to the prostate or has spread.
4. Genetics: Some inherited mutations, including BRCA-related changes, can increase risk and affect treatment choices.

Diagnosis / how it's measured

Diagnosis usually begins with a history, physical examination, PSA blood test, and often a digital rectal exam. PSA, or prostate-specific antigen, is a protein made by prostate tissue. PSA can be raised by cancer, but also by benign enlargement, inflammation, infection, ejaculation, or recent instrumentation. Because of this, PSA alone cannot diagnose prostate cancer.

If concern remains, imaging and biopsy are used. Multiparametric MRI is now commonly used before biopsy in many centres because it can help identify suspicious areas and reduce unnecessary biopsies. The diagnosis is confirmed by prostate biopsy, often done with ultrasound guidance and sometimes targeted to MRI-visible lesions.

Common parts of the work-up include:

Test	Purpose
PSA blood test	Helps estimate risk and monitor over time
Digital rectal exam	Checks for nodules or hard areas
Multiparametric MRI	Looks for suspicious lesions and local extent
Prostate biopsy	Confirms cancer and provides grade
PSMA PET/CT or bone scan/CT	Used in selected patients to look for spread

After diagnosis, staging combines PSA, biopsy grade, imaging, and exam findings. This helps classify the cancer as low, intermediate, or high risk, and guides treatment choices.

Evidence and uses

Treatment depends on stage, grade, symptoms, age, general health, and patient preferences. Not every prostate cancer needs immediate treatment. For carefully selected men with low-risk localised disease, active surveillance is an evidence-based option. This means close monitoring with repeat PSA tests, exams, imaging, and sometimes repeat biopsy, with treatment started only if the cancer shows signs of progression.

Main treatment approaches include:

1. Active surveillance: Often used for low-risk localised cancer.
2. Surgery: Radical prostatectomy removes the prostate and sometimes nearby lymph nodes.
3. Radiation therapy: External beam radiation or brachytherapy can treat localised disease.
4. Hormone therapy: Used for recurrent, locally advanced, or metastatic disease.
5. Chemotherapy: Often used in advanced or castration-resistant disease.
6. Targeted or precision treatments: Used in selected patients based on tumour genetics or imaging findings.

For metastatic disease, treatment has improved in recent years with combinations of androgen deprivation therapy and newer hormonal agents, chemotherapy, or other systemic treatments. Some patients may also receive bone-directed treatment if cancer has spread to bone.

Survival varies widely by stage. Localised prostate cancer often has a very good outlook, while metastatic disease is more serious and usually treated as a long-term controllable illness rather than a curable one. Early-stage disease may cause no symptoms, but advanced disease can lead to urinary obstruction, bone pain, weight loss, fatigue, or kidney problems.

In India, treatment is available across tertiary cancer centres, urology departments, and radiation oncology units. Access to MRI, PSMA PET imaging, robotic surgery, and genomic testing may vary by city and hospital. Cost, travel, and follow-up capacity often influence whether active surveillance, surgery, or radiation is the most practical option.

When to see a clinician

See a clinician if you have urinary symptoms that are new, persistent, or worsening, especially difficulty urinating, weak stream, blood in urine or semen, or pain with urination. These symptoms are not specific for cancer, but they should be assessed.

Urgent review is important if there is severe back pain, new leg weakness, loss of bladder or bowel control, or unexplained bone pain, because advanced prostate cancer can spread to the spine or bones. Men with a strong family history of prostate cancer, breast cancer, ovarian cancer, pancreatic cancer, or known BRCA-related mutations should ask whether earlier risk assessment or genetic counseling is appropriate.

Screening is a shared decision rather than an automatic test for everyone. The balance of benefit and harm depends on age, life expectancy, family history, and personal values. A urologist or oncologist can explain whether PSA testing, MRI, biopsy, or surveillance makes sense in a specific situation.

Limitations and open questions

A major challenge in prostate cancer is overdiagnosis and overtreatment. Some cancers found on screening would never have caused symptoms, yet treatment can lead to urinary incontinence, erectile dysfunction, and bowel side effects. This is why risk stratification and active surveillance are important.

Another limitation is that PSA is useful but imperfect. It can miss some cancers and can also be elevated for non-cancer reasons. MRI and newer imaging such as PSMA PET have improved detection and staging, but they are not equally available everywhere and do not remove the need for careful clinical judgment.

Research is ongoing on who benefits most from screening, how to reduce unnecessary biopsy and treatment, and how best to use genomic tests and newer systemic therapies. Evidence is also evolving on the best treatment combinations for advanced disease and on how inherited mutations should change screening and treatment pathways.