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Irradiator Commissioning and Dosimetry for Assessment of LQ α and β Parameters, Radiation Dosing Schema, and in vivo Dose Deposition
Published on: March 11, 2021
Radiation dose-volume effects and the penile bulb
Mack Roach1, Jiho Nam, Giovanna Gagliardi
1Department of Radiation Oncology, University of California-San Francisco, San Francisco, CA 94143-1708, USA. mroach@radonc.ucsf.edu
International Journal of Radiation Oncology, Biology, Physics
|February 23, 2010
Summary
External-beam radiotherapy for penile cancer may cause impotence. Keeping radiation dose to the penile bulb below 50 Gy may reduce this risk, but preserving tumor coverage is essential.
Area of Science:
- Radiation Oncology
- Urology
- Medical Physics
Background:
- Penile cancer treatment often involves external-beam radiotherapy (EBRT).
- Erectile dysfunction (ED) is a significant side effect of penile cancer treatment.
- The penile bulb's role in erectile function and its response to radiation is not fully understood.
Purpose of the Study:
- To review dose, volume, and clinical outcome data for the penile bulb in patients treated with EBRT.
- To identify dosimetric and clinical factors associated with post-treatment impotence.
- To provide recommendations for radiation dose constraints to the penile bulb.
Main Methods:
- Systematic review of published studies on EBRT for penile cancer.
- Analysis of dosimetric parameters (e.g., mean dose, D70, D90) and clinical factors (age, comorbidities).
- Correlation of radiation parameters with reported rates of impotence.
Main Results:
- Most studies indicate a link between radiation dose to the penile bulb and impotence.
- Age and comorbid diseases are also associated with increased risk of ED.
- Recommended mean dose to 95% of the penile bulb volume should be <50 Gy.
- Limiting D70 to 70 Gy and D90 to 50 Gy may be beneficial, without compromising target volume coverage.
Conclusions:
- The penile bulb may serve as a surrogate for critical erectile structures.
- Adhering to specific dose constraints for the penile bulb may mitigate the risk of radiation-induced impotence.
- Further research is needed to identify the precise critical structures for erectile function.
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