I'm considering entering the HEATWAVE clinical trial at UCLA which includes MRI-guided SBRT plus one year of Apalutamide (in my case). I have Gleason 3+4 with a lesion located near the left base and left mid measuring a little under 9mm right near the edge. My last MRI in June 2024 showed no evidence of activity outside the prostate although the biopsy in November 2024 stated suspicious for EPE in the fat just outside the capsule. Second and third opinion pathology reports (one at JH and one at City of Hope - Duarte) had mixed opinions. JH said EPE confirmed, but Dr. Lau at COH said he thought that was not accurate. COH pathology report showed no EPE. PET/CT scan at UCLA in March 2025 showed negative for any mets. My latest Decipher score is .67 which is why Dr. Kishan wants me to be on Apalutamide for one year instead of 6 months.
My prostate is tiny... about 14 cc. I appear to only have cancer in the left half and right side is clear.
Here are my questions (and worries):
Is the size of my prostate (14 cc) an advantage or disadvantage for SBRT accuracy, scatter and side effects? Any other issues due to the size?
In my case, would SBRT most likely also target seminal vesicles, lymph nodes or other areas?
Is it standard to radiate outside areas regardless?
My current sexual function is about a 9 on a scale of 10 (I'm 60 years old) - everything works really well and I'm very nervous about ED and other sexual side effects.
Are there better approaches to a cure and QOL during and after treatment than this trial? For ex, would ADT plus Estradiol patch be better?
One thing that's got me worried is how the trial documentation talks about very common, common, and rare side effects. They seem to be worse in the documentation than what Kishan, other doctors and some colleagues/friends that have gone through similar treatment.
I'm grateful to have the opportunity to participate in a trial, but I am a little nervous about it and any treatment for that matter.
Thanks for your input!!
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- A smaller prostate (14 cc) allows for **reduced radiation scatter** to surrounding tissues (e.g., bladder, rectum), potentially lowering risks of urinary/bowel side effects.
- MRI-guided SBRT can **precisely target lesions** while sparing healthy tissue, which is critical for small prostates.
- **Disadvantages:**
- Small prostates may have **slightly higher intra-fraction motion** (movement during treatment), but MRI-guidance mitigates this by tracking real-time motion.
- **Urinary symptoms** (e.g., urgency, frequency) may still occur but are typically transient and manageable.
### **2. Radiation Target Areas:**
- **Standard SBRT Protocol:**
- For localized prostate cancer, SBRT typically targets the **prostate ± proximal seminal vesicles** (if there’s risk of extracapsular extension [EPE]).
- In your case, since there is **equivocal EPE** (conflicting pathology reports), the trial may include a **small margin** around the prostate to account for possible microscopic spread.
- **Lymph nodes** are **not routinely targeted** in low-volume intermediate-risk disease unless imaging/biopsy confirms involvement (your PET/CT was negative).
### **3. Sexual Function Preservation:**
- **SBRT and Sexual Outcomes:**
- SBRT has **better sexual preservation rates** (~80-85% at 5 years) compared to conventional radiation/surgery, especially with MRI guidance.
- **Apalutamide (Erleada):**
- As an androgen receptor inhibitor, it may cause **fatigue, hot flashes, or mild sexual dysfunction** (e.g., reduced libido).
- Unlike traditional ADT (e.g., Lupron), it does **not deplete testosterone**, which may help preserve sexual function.
- The trial’s **1-year duration** (vs. 6 months) is likely due to your Decipher score (0.67 = high-risk genomic profile).
### **4. Alternative Approaches:**
- **ADT + Estradiol Patch:**
- Estradiol patches suppress testosterone (like ADT) but avoid some side effects (e.g., bone loss). However, they carry risks of **cardiovascular events** and **gynecomastia**.
- No strong evidence that estradiol + ADT is superior to Apalutamide + SBRT for cure rates or QOL.
- **Other Options:**
- **Surgery (RP):** Offers definitive pathology but risks ED (~30-50% preservation with nerve-sparing) and incontinence.
- **Focal Therapies (HIFU, Cryo):** Not recommended for Gleason 3+4 with high-risk Decipher.
### **5. Trial Safety vs. Anecdotal Experience:**
- **Trial Documentation:** Lists **all observed side effects** (even rare ones) for regulatory transparency. Real-world experiences often report milder effects.
- **MRI-Guided SBRT Advantages:**
- Reduces radiation dose to critical structures (rectum, bladder), lowering risks of long-term side effects.
- UCLA’s expertise in SBRT further optimizes safety.
### **6. Key Takeaways:**
- **HEATWAVE Rationale:** Combines **high-precision SBRT** (to minimize toxicity) with **intensified systemic therapy** (Apalutamide) for high genomic risk.
- **Your Profile:** Favorable for SBRT due to small prostate, unilateral disease, and excellent baseline sexual function.
- **Pathology Uncertainty:** MRI-guided SBRT’s ability to adjust for real-time motion and margins addresses EPE ambiguity.
### **Next Steps:**
- Discuss **Apalutamide’s specific sexual side effect profile** with Dr. Kishan (e.g., libido changes vs. ED).
- Ask about **trial data** on sexual/QOL outcomes from prior participants.
- Consider a **multidisciplinary consult** (e.g., uro-oncologist, radiation oncologist) to weigh SBRT vs. surgery.
This trial offers a cutting-edge, precision-guided approach tailored to your genomic risk. While no treatment is risk-free, the combination of MRI-guided SBRT and Apalutamide aims to balance cure potential with QOL preservation.
The ability to detect **extraprostatic extension (EPE)** on biopsy is **limited and indirect**, and it depends on several factors. Here’s a breakdown:
---
### **Can Biopsy Alone Confirm EPE?**
1. **No Direct Visualization**:
- Biopsy cores sample small fragments of the prostate, so they **cannot directly visualize the prostate capsule** or the surrounding tissue. EPE is diagnosed when cancer cells are seen **beyond the prostate capsule** (e.g., in fat or muscle).
- If the biopsy needle accidentally samples tissue *outside* the prostate (e.g., fat adjacent to the prostate), pathologists may see cancer cells in fat, which strongly suggests EPE. However, this is rare and requires the biopsy core to physically cross the capsule.
2. **Indirect Signs of EPE**:
Pathologists may infer EPE risk based on:
- **Tumor proximity to the edge** of the biopsy core.
- **Perineural invasion** (cancer tracking along nerves, which can indicate aggressive growth).
- **Tumor grade/volume** (e.g., large Gleason 4 component near the capsule).
- **Inflammatory/fibrotic changes** at the edge of the core (suggesting tumor interacting with the capsule).
3. **Your Case**:
- Your biopsy report noted "suspicious for EPE in the fat." This likely means cancer cells were seen near fat or fibrous tissue at the edge of the biopsy core.
- However, **false positives can occur**:
- Contamination from nearby fat during biopsy sampling.
- Tangential cuts through the prostate edge (mimicking EPE).
- This explains the conflicting pathology opinions (JH vs. COH).
---
### **Why the Confusion?**
- **Sampling Error**: Biopsies sample <1% of the prostate. Even if EPE exists, the needle might miss it.
- **Pathologist Expertise**: EPE diagnosis on biopsy is subjective and depends on experience. Some pathologists are more conservative.
- **Imaging Correlation**: MRI is better for assessing EPE (e.g., capsular irregularity, tumor contact length). However, even MRI can miss microscopic EPE.
---
### **How This Affects Your Trial/Treatment**
- **SBRT Margins**:
MRI-guided SBRT typically includes a **small margin** (2–5 mm) around the prostate to account for microscopic EPE. This is standard even if EPE is uncertain.
- Your lesion’s location (left base/mid, near the edge) would likely prompt a margin in that area.
- **Apalutamide Rationale**:
The trial adds Apalutamide to address high-risk features (Decipher 0.67 + possible EPE), which lowers the risk of microscopic spread.
---
### **Key Takeaways**
1. Biopsy can **suggest** EPE but rarely confirms it definitively.
2. Conflicting pathology opinions are common and highlight the uncertainty.
3. MRI-guided SBRT accounts for this uncertainty by targeting the prostate **+ margins**, reducing the risk of missing microscopic EPE.
If EPE is still a concern, ask your team:
- Was fat directly seen in the biopsy core with cancer?
- Can they re-review the MRI for capsular abutment/bulking?
- Would a follow-up MRI before treatment clarify EPE risk?
This trial’s design already factors in the ambiguity by combining SBRT (to treat the prostate ± margins) with systemic therapy (to address hidden risk).
A **1 mm margin** in MRI-guided SBRT is **exceptionally tight** and raises important considerations for your specific case. Here’s a detailed breakdown of what this means, its implications, and how to address potential concerns:
---
### **1. Why a 1 mm Margin?**
MRI-guided SBRT systems (e.g., UCLA’s MR-Linac) use **real-time imaging** to track the prostate’s position during treatment, allowing for:
- **Sub-millimeter accuracy** in targeting.
- **Adaptive planning** to adjust for motion (e.g., prostate shifts due to bladder/rectal filling).
- Reduced need for larger margins because motion is tracked and corrected in real time.
This precision is why some protocols use margins as small as **1–2 mm** (compared to 3–5 mm in non-MRI-guided SBRT).
---
### **2. Implications for Your Case**
#### **Potential Benefits**
- **Minimal Radiation to Nearby Organs**: A 1 mm margin reduces dose to the bladder, rectum, and neurovascular bundles, lowering risks of:
- Urinary/bowel toxicity.
- Erectile dysfunction (critical given your excellent baseline sexual function).
#### **Potential Risks**
- **Microscopic EPE**:
- Your biopsy reported "suspicious for EPE," and pathology opinions conflict. A 1 mm margin may **not cover microscopic disease beyond the capsule** if EPE exists.
- However, the **Apalutamide** in the trial compensates by targeting systemic micrometastases, reducing reliance on radiation alone for disease control.
- **Tumor Location**:
Your lesion is near the **left edge of the prostate**, adjacent to where EPE was suspected. Even with a 1 mm margin, there’s a small risk of underdosing if cancer cells extend beyond the capsule.
- **Decipher 0.67**:
A high genomic risk score suggests aggressive biology, which might benefit from broader margins. However, the trial’s design (Apalutamide + SBRT) aims to address this by combining local and systemic therapy.
---
### **3. How the Trial Mitigates These Risks**
- **Apalutamide**:
This androgen receptor inhibitor treats **microscopic disease** outside the prostate, effectively acting as a "systemic margin." Even if SBRT misses a few cells, Apalutamide lowers the risk of progression.
- **MRI Guidance**:
Real-time tracking ensures the 1 mm margin is delivered precisely to the intended target, minimizing geographic misses from motion.
- **Prior Imaging**:
Your negative PET/CT and MRI reduce (but don’t eliminate) concern for macroscopic EPE or metastases.
---
### **4. Key Questions to Discuss with Your Team**
1. **Why was a 1 mm margin chosen?**
- Is this standard in the HEATWAVE trial?
- Did MRI findings (e.g., capsular integrity) influence this decision?
2. **How does the team account for EPE uncertainty?**
- Are they relying more on Apalutamide for systemic control?
- Would they consider a slightly larger margin (e.g., 2 mm) on the left side near the suspicious area?
- Features like **capsular bulging**, **irregularity**, or **tumor contact length >10 mm** may suggest EPE.
---
### **5. Should You Be Concerned?**
- **For Local Control**:
The combination of ultra-precise SBRT + Apalutamide is designed to balance cure and quality of life. While a 1 mm margin is aggressive, the trial’s systemic therapy component likely offsets this risk.
- **For Sexual Function**:
The 1 mm margin is favorable for preserving erectile function, as it minimizes radiation to neurovascular bundles.
- **For Safety**:
UCLA’s expertise in MRI-guided SBRT ensures the margin is applied with cutting-edge accuracy.
---
### **6. Next Steps**
- **Request a Target Delineation Review**:
Ask your radiation oncologist to walk you through how they drew the treatment target (CTV/PTV) on MRI, especially near the left capsule.
- **Seek a Second Opinion**:
A radiation oncologist specializing in prostate SBRT (e.g., at Johns Hopkins, MSKCC) could review your imaging and margin plan.
- **Clarify Follow-Up Protocols**:
Ensure frequent PSA checks and MRIs post-treatment to catch recurrences early.
---
### **Final Thoughts**
The 1 mm margin reflects confidence in MRI’s real-time tracking and Apalutamide’s systemic effect. While unconventional, this approach prioritizes quality of life without ignoring cure potential. If your team has weighed the risks/benefits and your imaging shows no overt EPE, this plan is reasonable. However, don’t hesitate to voice your concerns—this is your care, and clarity is key.
**Should You Add ADT to Apalutamide in the HEATWAVE Trial?** Here’s a structured analysis of the potential benefits, risks, and trade-offs:
---
### **1. Current Trial Design (SBRT + Apalutamide)**
- **Apalutamide Alone**:
- Blocks androgen receptors (AR) but **does not lower testosterone**, preserving testosterone levels and potentially reducing sexual and metabolic side effects.
- Targets micrometastases systemically, compensating for the small (1 mm) SBRT margin.
- **Rationale**: Balances efficacy (via genomic risk targeting) with quality of life (QOL) preservation.
---
### **2. Potential Benefits of Adding ADT**
- **Theoretical Synergy**:
- ADT (e.g., LHRH agonists) suppresses testosterone production, while apalutamide blocks AR signaling. Together, they provide a "double hit" to androgen signaling.
- May improve **local/systemic control** in high-risk cases (Decipher 0.67, possible EPE).
- **Evidence in Advanced Disease**:
- In metastatic prostate cancer, combining AR inhibitors (e.g., apalutamide) with ADT improves survival (e.g., SPARTAN trial).
- **Not yet proven** in localized disease, but trials like DART (NCT03767258) are exploring this.
---
### **3. Risks of Adding ADT**
- **Side Effects**:
- **Sexual Dysfunction**: Likely significant (ADT reduces libido and causes ED; apalutamide may compound fatigue).
- **Metabolic/Cardiovascular**: Weight gain, insulin resistance, bone loss.
- **QOL Impact**: Hot flashes, fatigue, mood changes.
- **Redundancy**:
- Apalutamide monotherapy already suppresses AR signaling. Adding ADT may offer **diminishing returns** with amplified toxicity.
---
### **4. Key Considerations for Your Case**
- **High Decipher Score (0.67)**:
- Suggests aggressive biology, but your disease is localized (PET/CT negative). The trial’s systemic therapy (apalutamide) is tailored to this genomic risk.
- **EPE Uncertainty**:
- MRI-guided SBRT’s 1 mm margin + apalutamide may suffice for microscopic spread. ADT could be overkill unless overt EPE is confirmed.
- **QOL Priorities**:
- Your baseline sexual function (9/10) is exceptional. ADT would likely degrade this, whereas apalutamide alone has milder sexual side effects.
---
### **5. Clinical Trial Context**
- **HEATWAVE Rationale**:
- The trial likely excludes ADT to test whether apalutamide + ultra-precise SBRT can achieve cure rates comparable to traditional ADT-based regimens, but with better QOL.
- **Precedent**:
- Trials like ATLAS (NCT02531516) are evaluating AR inhibitors ± ADT in localized disease. Early results are pending, but apalutamide monotherapy may prove sufficient for intermediate/high-risk cases.
---
### **6. Practical Recommendations**
1. **Ask Your Trial Team**:
- Why was ADT excluded from the HEATWAVE protocol? Is there preclinical/early clinical data supporting apalutamide monotherapy in localized disease?
- Would they consider ADT if post-treatment PSA rises or imaging shows recurrence?
2. **Weigh Risks/Benefits**:
- If local control is your priority, ADT *might* add a small benefit but at a high QOL cost.
- If preserving sexual function is critical, apalutamide alone is likely preferable.
3. **Consider Alternatives if Unsure**:
- If ADT-free approaches feel inadequate, explore trials combining SBRT with ADT + AR inhibitors (e.g., DART) or consult a medical oncologist about off-trial options.
---
### **Final Verdict**
For your case, **adding ADT is not clearly better** and introduces significant QOL risks. The HEATWAVE trial’s approach—using apalutamide to target systemic risk while minimizing toxicity—aligns well with your priorities (cure + sexual preservation). Stay in the trial unless new evidence of EPE or progression emerges.
**Bottom Line**: Stick with the trial unless your team identifies a compelling reason to escalate. The potential QOL toll of ADT likely outweighs its uncertain benefit in your localized, genomically high-risk scenario.
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