Radiotherapy for Prostate Cancer: What Approach Works Best?

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The Latest on Radiotherapy for Prostate Cancer

New Meta-Analysis Sheds Light on Optimal Treatment Approaches

By IPCSG Medical News Team - April 2025

A comprehensive new meta-analysis has provided important insights into the effectiveness and side effects of different radiotherapy approaches for prostate cancer treatment. This research could help patients and their doctors make more informed decisions about radiation treatment options.

Key Findings

Moderately hypofractionated radiotherapy, both isodose and dose-escalated, showed progression-free survival outcomes similar to conventionally fractionated radiotherapy in patients with prostate cancer. However, the dose-escalated hypofractionated regimen was associated with an increased risk of toxicities compared to the conventional approach.

The study, led by Dr. Amar U. Kishan from UCLA and Dr. Yilun Sun from University Hospitals Seidman Cancer Center in Cleveland, analyzed data from seven Phase 3 trials involving 5,880 prostate cancer patients. These patients received either conventionally fractionated radiotherapy or moderately hypofractionated radiotherapy.

Understanding the Radiotherapy Options

For those unfamiliar with these terms:

• Conventionally fractionated radiotherapy: Traditional approach delivering smaller radiation doses (typically 1.8-2 Gy) daily over a longer period (often 8-9 weeks)
• Moderately hypofractionated radiotherapy: Delivers higher doses per treatment (2.5-4 Gy) over fewer sessions (typically 4-5 weeks)
  • Isodose: Maintains the same overall biological effect as conventional treatment
  • Dose-escalated: Increases the overall biological effect compared to conventional treatment

Effectiveness vs. Side Effects

The meta-analysis found that progression-free survival was not significantly different between patients who received either form of moderately hypofractionated radiotherapy compared to conventionally fractionated radiotherapy. Overall survival rates were also similar between the approaches.

However, the side effect profiles differed:

When comparing conventional radiotherapy to isodose moderately hypofractionated radiotherapy, there was no significant increase in late genitourinary toxicities (urinary problems) or gastrointestinal toxicities (bowel problems) in the hypofractionated group.

In contrast, dose-escalated moderately hypofractionated radiotherapy was associated with significantly higher odds of experiencing late gastrointestinal toxicities. Patients receiving this treatment were also more likely to experience a decrease in bowel-related quality of life.

Why This Matters for Patients

This research provides the strongest evidence to date suggesting that the isodose hypofractionated regimen could be the preferred approach for all risk groups of prostate cancer. It offers similar cancer control to conventional radiotherapy without significantly increasing side effects, while reducing the overall treatment time from about 8-9 weeks to 4-5 weeks.

This shorter treatment schedule can be particularly beneficial for:

• Patients who live far from treatment centers
• Those who find it difficult to attend frequent appointments
• Reducing the overall burden on healthcare systems

Expert Perspective

The study authors concluded that the isodose regimen could be the preferred hypofractionated approach for all risk groups. However, in an accompanying editorial, other experts questioned whether these conclusions about dose-escalated moderately hypofractionated radiotherapy would "hold true in an era of focal boosting and [stereotactic body radiotherapy]."

The Bigger Picture

This meta-analysis fits into a broader trend in prostate cancer treatment. Research indicates that hypofractionated approaches can be both cost-effective and patient-friendly, particularly in areas where healthcare resources are limited.

As noted by Florida Cancer Specialists & Research Institute, hypofractionated radiotherapy "shortens the overall duration of radiation therapy by delivering fewer treatments but with a higher dose of radiation per daily treatment resulting in similar positive outcomes with no additional side effects."

What This Means for You

If you're considering radiotherapy for prostate cancer, discuss these findings with your healthcare team. The isodose moderately hypofractionated approach may offer similar cancer control to conventional approaches with the benefit of a shorter treatment schedule.

Remember that treatment decisions should be individualized based on your specific cancer characteristics, overall health, and personal preferences.

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Sources:

1. "Radiotherapy for Prostate Cancer: What Approach Works Best?" Medscape, edited by Gargi Mukherjee. Link to Medscape
2. "Are we ready for a paradigm shift from high-dose conventional to moderate hypofractionated radiotherapy in intermediate-high risk prostate cancer?" ScienceDirect. Link
3. "Conventional versus hypofractionated high-dose intensity-modulated radiotherapy for prostate cancer: 5-year outcomes of the randomised, non-inferiority, phase 3 CHHiP trial." PMC. Link
4. "Rationale, conduct, and outcome using hypofractionated radiotherapy in prostate cancer." PMC. Link
5. "Practical considerations for prostate hypofractionation in the developing world." Nature Reviews Urology. Link
6. "Hypofractionation Radiotherapy For Prostate Cancer." Florida Cancer Specialists & Research Institute. Link
7. "Moderate hypofractionated radiotherapy vs conventional fractionated radiotherapy in localized prostate cancer: a systemic review and meta-analysis from Phase III randomized trials." PMC. Link
8. "Rectal/urinary toxicity after hypofractionated vs conventional radiotherapy in low/intermediate risk localized prostate cancer: systematic review and meta analysis." PubMed. Link

Radiotherapy for Prostate Cancer: What Approach Works Best?

medscape.com

Edited by Gargi Mukherjee

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TOPLINE:

Moderately hypofractionated radiotherapy, both isodose and dose-escalated, led to progression-free survival outcomes similar to that achieved with conventionally fractionated radiotherapy in patients with prostate cancer, but the dose-escalated regimen came with an increased risk for toxicities compared with the conventional approach, according to findings from a recent meta-analysis.

METHODOLOGY:

• Moderately hypofractionated radiotherapy is now the preferred standard for treating localized prostate cancer, but the optimal regimen remains uncertain.
• Researchers conducted a meta-analysis of seven phase 3 trials, which included 5880 patients with prostate cancer who received either conventionally fractionated radiotherapy or moderately hypofractionated radiotherapy.
• Three trials (n = 3454) compared conventionally fractionated radiotherapy with isodose moderately hypofractionated radiotherapy, and four trials (n = 2426) compared the conventional approach with dose-escalated hypofractionated approach. The median follow-up durations were 5.4 and 7.1 years, respectively.
• The meta-analysis included three separate assessments: Efficacy, physician-scored late toxicity, and patient-reported outcomes. The primary endpoint for efficacy was progression-free survival; overall survival was the secondary endpoint. The late toxicity analysis evaluated the incidence of late grade ≥ 2 genitourinary and gastrointestinal toxic effects as co-primary endpoints, with late grade ≥ 3 toxicity as secondary endpoints. The patient-reported outcomes were clinically important declines in urinary or bowel scores.

TAKEAWAY:

• Progression-free survival was not significantly different between patients who received isodose or dose-escalated moderately hypofractionated radiotherapy vs conventionally fractionated radiotherapy (hazard ratio [HR], 0.92 for isodose; P = .21; HR, 0.94 for dose-escalated; P = .43).
• Overall survival was also similar when comparing the hypofractionated treatments to the conventional approach (HR, 0.83 for isodose; P = .06, and HR, 0.92; P = .39 for dose-escalated).
• Compared with the conventional approach, isodose moderately hypofractionated radiotherapy was not associated with a greater likelihood of late grade ≥ 2 (odds ratio [OR], 1.16; P = .32) or grade ≥ 3 genitourinary toxicities (OR, 1.15; P = .27) as well as grade ≥ 2 (OR, 1.20; P = .51) or grade ≥ 3 (OR, 0.89; P = .76) gastrointestinal toxicities.
• Dose-escalated moderately hypofractionated radiotherapy, however, was associated with significantly higher odds of experiencing late grade ≥ 2 (OR, 1.48) and late grade ≥ 3 (OR, 1.80) gastrointestinal toxicities. Patients who received the dose-escalated regimen were also more likely to experience a decrease in bowel quality of life (OR, 1.68).

IN PRACTICE:

This meta-analysis provides the strongest evidence to date suggesting an isodose regimen could be the preferred hypofractionated regimen for all risk groups, the authors concluded.

However, whether the authors’ conclusions concerning dose-escalated moderately hypofractionated radiotherapy “hold true in an era of focal boosting and [stereotactic body radiotherapy] is a matter of constructive debate,” authors of an accompanying editorial wrote.

SOURCE:

This study, led by Amar U. Kishan, MD, Department of Radiation Oncology, University of California Los Angeles, and Yilun Sun, PhD, Department of Radiation Oncology, University Hospitals Seidman Cancer Center, Cleveland, was published online in The Lancet Oncology.

LIMITATIONS:

Differences in trial definitions for progression-free survival and toxicity required data harmonization. Patient-reported outcomes were not available for three trials, limiting the robustness of these analyses. The median follow-up was relatively short, and very late differences in toxicity and efficacy might manifest with extended follow-up. Time-to-toxicity data were not available, and therefore, physician-scored toxic effect data were evaluated as binary events rather than time-based incidences.

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DISCLOSURES:

This study did not receive any specific funding. Several authors reported receiving personal fees or grants and having other ties with various sources.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.