Stage 3 Prostate Cancer: A Guide to Diagnosis, Treatment, and Next Steps

This guide is designed to provide you with an overview of your diagnosis, potential treatment paths, and what to expect. It is meant to be an educational tool to facilitate a productive and informed conversation with your medical oncology team.

Understanding Stage 3 Prostate Cancer Staging and Gleason Score

Prostate adenocarcinoma is the most common type of prostate cancer, and adenocarcinoma simply means the cancer originated in the gland cells (the cells that normally produce the prostate fluid).

A diagnosis of stage 3 indicates that the cancer is locally advanced. This means the tumor is large enough to have grown through the prostate capsule and may have spread to nearby tissues, such as the seminal vesicles, but has not spread to distant parts of the body, known as metastasis.

The staging process relies on three key pieces of information, often summarized as the TNM system:

• T (Tumor): The size and extent of the primary tumor. In stage 3, this is classified as T3 or T4.
• N (Nodes): Whether the cancer has spread to nearby lymph nodes. For most Stage 3 classifications, this is N0 (no regional lymph node spread), though some T3 cases with N1 (spread to regional lymph nodes) may be grouped differently.
• M (Metastasis): Whether the cancer has spread to distant sites. For Stage 3, this is M0 (no distant metastasis).

Your Gleason score or Grade Group will also be crucial. These scores measure how aggressive the cancer cells appear under a microscope, influencing treatment choice and prognosis. A higher score (e.g., Gleason 4+3=7 or greater, or Grade Group 2 or higher) suggests a more aggressive tumor.

Diagnostic Tests: PSA, Biopsy, and Imaging for Localized Cancer

The process of diagnosis and staging involves several steps:

1. Biopsy: A procedure to remove small tissue samples from the prostate. This confirms the presence of adenocarcinoma and determines the Gleason Score.
2. Prostate-specific antigen (PSA) blood test: High PSA levels often correlate with larger or more advanced tumors, though PSA alone cannot determine the stage.
3. Imaging tests: These are essential for determining the extent of local spread and checking for distant metastasis:

• Magnetic resonance imaging (MRI): Often used to visualize the prostate gland, seminal vesicles, and nearby tissues, which is critical for Stage 3 assessment.

Multimodality Treatment Options for Locally Advanced Prostate Cancer

Because the cancer is locally advanced, the goal of treatment is typically to aggressively target the tumor while reducing the chance of local recurrence or distant spread.

Dr. Kai Tsao, system chief of solid tumor oncology, and he is also medical director of the R.J. Zuckerberg Cancer Center at Northwell Cancer Institute and director of Northwell's medical oncology prostate cancer program, explained in an interview with CURE that many advances have been made across prostate cancer treatment settings.

“From the localized disease side, we've made many advancements, particularly understanding who can be watched in a method called active surveillance and who should be treated,” Tsao said. “There is also currently molecular testing that's available to guide doctors and clinicians in how to approach a patient's prostate cancer. So certainly, that is a very personalized approach that patients can benefit from.”

Treatment is often a multimodality approach, meaning a combination of therapies.

Radiation Therapy (RT)

This is a common and highly effective primary treatment for patients with stage 3 disease. High-energy beams are used to kill cancer cells.

• External beam radiation therapy (EBRT): Delivers radiation from a machine outside the body. Modern techniques, like intensity-modulated radiation therapy (IMRT), aim to precisely shape the radiation dose to the tumor while sparing surrounding healthy tissue.
• Brachytherapy: Placing radioactive seeds directly into the prostate gland. This may be used alone for less aggressive T3 tumors or in combination with EBRT for a higher dose.

Hormone Therapy

Prostate cancer cells often rely on male hormones to grow. Androgen-deprivation therapy (ADT) works by lowering the level of these hormones in the body, which slows the growth of the cancer or causes it to shrink.

• Luteinizing hormone-releasing hormone (LHRH) agonists or antagonists: Medications that stop the testicles from producing testosterone.
• Duration: For stage 3 cancer, ADT is almost always used before, during, and after radiation therapy (neoadjuvant, concurrent, and adjuvant ADT), often lasting from 18 to 36 months, to increase the effectiveness of the radiation.

Radical Prostatectomy

Surgical removal of the entire prostate gland and seminal vesicles, and often some surrounding lymph nodes, may be an option, particularly for otherwise healthy men with T3a disease, which means the cancer is confined to the immediate surrounding tissue, not the seminal vesicles.

• Postsurgical treatment: Patients who undergo surgery for stage 3 cancer often require adjuvant, or postoperative radiation therapy, and/or ADT to minimize the risk of recurrence.

Clinical Trials

You may be eligible for clinical trials investigating new combinations of existing therapies or entirely new drugs. Discuss this option with your oncologist, as it can offer access to cutting-edge treatments.

Managing Side Effects: Radiation, Hormone Therapy, and Surgery

Treatment side effects vary based on the specific regimen. Open communication with your care team about managing these effects is vital.

The combination of radiation and ADT often amplifies some side effects, such as fatigue and ED. Your team can recommend specific medications or lifestyle changes to manage these.

Key Questions for Your Oncologist and Next Steps in Stage 3 Prostate Cancer

A diagnosis of stage 3 prostate adenocarcinoma is serious, but it is highly treatable. The combination of surgery, radiation, and hormone therapy has led to excellent long-term outcomes for many male patients.

Your next steps should focus on gathering information to make an informed treatment decision:

1. Consult with a multidisciplinary team: You should meet with a urologist and a radiation oncologist to discuss the pros and cons of surgery versus radiation-based treatment for your specific case.
2. Review your specific details: Ask your oncologist about your exact T-stage classification, Gleason Score/Grade Group, and initial PSA level. These factors will heavily influence the recommended treatment plan.
3. Discuss clinical trials: Ask if there are any suitable clinical trials available in your area.
4. Prioritize quality of life: Discuss potential side effects, especially erectile function and urinary control, with both your surgeon and radiation oncologist to understand how each treatment may impact your long-term quality of life.

This guide is designed to be a starting point. Your personal experience will be unique. By using this information as a foundation for your discussions, you can partner with your oncologist to make the best decisions for your health.

Editor's note: This article is for informational purposes only and is not a substitute for professional medical advice. Please contact your healthcare team with any questions or concerns.

References

1. “What Does a Stage 2 Prostate Cancer Diagnosis Mean for Me?” by Gina Mauro. CURE; Nov. 2, 2025. https://www.curetoday.com/view/what-does-a-stage-2-prostate-cancer-diagnosis-mean-for-me-
2. “Breaking Down the Prostate Cancer Treatment Renaissance,” by Kai Tsao. CURE; December 9, 2025. https://www.curetoday.com/view/breaking-down-the-prostate-cancer-treatment-renaissance

For more news on cancer updates, research and education, don’t forget to subscribe to CURE®’s newsletters here.