Daniel A. Hamstra, MD
Dean A. Shumway MD
Steven Eric Finkelstein, MD
Felix Feng, MD
Why is this article contemporary?
The options and alternatives for managing prostate cancer with radiation continue to expand. Herein, Heath et al provide a contemporary discussion of factors influencing patient reported rectal toxicity following external beam radiation therapy for prostate cancer.
In our current health climate, posttreatment health-related quality of life (HRQOL) is emerging as a main concern of patients. Measuring patient-reported HRQOL using validated survey instruments suggests these measures are more sensitive compared to physician-reported toxicity guidelines as counterparts.
Patient-reported HRQOL following radiation therapy remains strongly dependent on the technique, the total radiation dose delivered, and dosevolume relationships with different portions of the rectum. Imageguided radiation therapy and pelvic tissue spacers are 2 recent technical advancements that have facilitated limitation of untoward rectal toxicity.
Counseling is key with patient education focused that rectal HRQOL is dependent on individualized baseline function and treatment option selected. To minimize toxicity with respect to radiation induced rectal side effects, consideration should be given to dose received not only by the whole rectum but particularly by the inferior rectum.
Heath et al suggests that rectal doses both greater than and less than 70 Gy may influence bowel QOL with stronger associations with higher doses. Indeed, a number of DVH constraints have been suggested by single institutions; with the exception of the rectal V70<25%, these largely await validation in multi-institutional studies.
Thus, to increase contemporary patient satisfaction following prostate cancer treatment future multiinstitutionally validated predictive guidelines should be advanced that permit for better communication of expectation for rectal HRQOL changes following treatment.
The high incidence and relatively low mortality rate associated with prostate cancer, in combination with a lack of clearly demonstrated survival benefit among numerous treatment options, has resulted in post-treatment health-related quality of life (HRQOL) emerging as a primary concern of patients. Measuring patient-reported HRQOL using validated survey instruments has shown that these measures are more sensitive and reliable compared to physician-reported toxicity guidelines, which have been traditionally utilized. Dose-volume histogram (DVH) guidelines for limiting rectal toxicity and improving patient-reported HRQOL have been established in numerous single-institution studies yet await multi-institutional validation. Limiting dose to the inferior rectum in particular has been shown to limit rectal toxicity and improve patient-reported rectal HRQOL in a subset of patients undergoing intensity-modulated radiation therapy (IMRT). Image-guided radiation therapy (IGRT) and pelvic spacers are 2 recent advancements that have also helped to limit rectal toxicity. Developing and validating a predictive model for patient-reported HRQOL remains an elusive target, and one that has great potential to further improve satisfaction with outcome following prostate cancer treatment in a great number of prostate cancer survivors.
Approximately one in 7 men living in the United States will be diagnosed with prostate cancer in their lifetime. However, it is estimated that as few as one in 38 men will die from this disease due in part to the natural history of the disease, as well as improved screening measures and treatment options.1
The 3 most common treatments for prostate cancer—radical prostatectomy (RP), brachytherapy (BT), and external beam radiation therapy (EBRT)—have all been shown to offer similar survival benefit and each has its own uniquely associated HRQOL implications following treatment.2
Due to the fact that most prostate cancer survivors do not die as a direct result of their disease, and over 94% of patients will live more than 15 years following diagnosis, HRQOL is often a primary concern for patients and physicians when determining a treatment plan.1,3
Offering patients concise predictive information on post-treatment HRQOL can be difficult due to the rapidly evolving technology used to treat prostate cancer in combination with patients and physicians often emphasizing different HRQOL outcomes.4
Due to the sensitivity of the rectum to radiation, efforts to reduce the dose to this area in the pelvis are often associated with improved patient-reported HRQOL as well as physician-scored toxicity.