Adverse events are an important clinical outcome in cancer treatment. This is to our knowledge the first analysis of RP using EORTC QLQ-PRT20 in a population from Latin America who underwent pelvic radiation therapy. This study provides an analysis of patients’ RP symptoms after pelvic radiotherapy. Overall, no significant differences were found in global QoL of patients when assessed using the EORTC QLQ-C30 questionnaire. This is an important endpoint and may reflect advances in the radiation therapy techniques resulting in more tolerable treatments. IMRT and 3DCRT decrease the rates of gastrointestinal toxicity (11) and IMRT is associated with lower deterioration of health-related QoL (12).
The assessment of QoL related to RP through EORTC QLQ-PRT20 questionnaire identified a statistically significant worsening of pain and bowel control after treatment with radiotherapy. In addition, the average number of daily bowel movements increased from 2.3 to 3.4 after radiotherapy, representing a significant 47% increase in bowel movement. This change was also found in the diarrhea scale of the EORTC QLQ-C30 questionnaire, where there was statistically significant increase in scores.
After treatment with radiotherapy, mean scores of pain had increased in 417.74%. Pain may be related to reduced QoL and difficulty performing daily activities. Dabrowska et al. assessed QoL in 83 patients in treatment for prostate cancer using EORTC QLQ-C30 questionnaire. They have reported that 33.7% of patients had pain that hampered performing daily activities and it was strongly correlated with patients' perception of QoL. Fatigue and the need to have a rest during the day was reported in 61.4% of patients, and that was also associated with poorer QoL (13).
Symptoms such as diarrhea, increased number of bowel movements, fecal urgency and anal incontinence were evaluated in the present study using the EORTC QLQ-PRT20 questionnaire. These are symptoms related to specific anorectal disorders that can be a result of pelvic radiotherapy. Decreased rest and squeeze pressures of anal sphincters and impaired rectal distensibility are associated with clinical presentation of urgency and anal incontinence. Impaired rectal capacity is also related to the increase in number of daily bowel movements (14).
In our study, patients had worsening of bowel control scores and increased symptoms related to leakage after radiotherapy treatment of the pelvis. Bowel control was addressed with questions that describe fecal urgency and tenesmus. Fecal urgency has an important impact on patients' QoL. It is one of the most evaluated symptoms in late anorectal changes after radiotherapy, but it is usually not accessed through QoL questionnaires, as shown by Bonet et al. in 2018. They assessed the QoL of 75 patients undergoing pelvic radiotherapy for prostate cancer using two questionnaires, EPIC (Expanded Prostate Cancer Index Composite) and LENT / SOMA (Late Effects of Normal Tissue/Subjective, Objective, Management, Analytic), and included two questions about fecal urgency. Symptoms of fecal urgency increased significantly after treatment, but only the additional questions were able to identify this change. (15).
In the present study, patients who received doses of up to 45 Gy were at increased risk of developing leakage when compared to patients who received doses greater than 60 Gy. This finding is contrary to data found in literature, in which increased doses are associated to increased risk of RP (2). This discrepancy can be attributed to the sample size, especially in the group that received lower doses (4 patients). In addition, dose fractioning and biological equivalence were not evaluated, factors that may influence in intestinal toxicity (11, 16).
Fatigue is a prevalent symptom associated with cancer or cancer treatment and has an impact on emotional, cognitive and physical distress, impairing patients' QoL (17). Patients evaluated in our study had a significant increase in fatigue scores after radiotherapy. Jakobsson et al. evaluated the linkage between fatigue and intestinal injury during radiotherapy in patients with anal e uterine cancer. The authors identified the association between fatigue and intestinal radiation lesions In addition, there was an association between fatigue scores and increase in diarrhea and in EORTC QLQ-C30 diarrhea scores (18). The association between fatigue and diarrhea was also found by Gonzalez et al. in a study that evaluated 102 patients undergoing cancer treatment (19).
In our study, clinical features analyzed did not impact in RP-related QoL, although some patients’ risk factors, such as diabetes and smoking, are known to increase radiation toxicity (20, 21). Akthar et al. found that age older than 63 years, BMI over 29 and current tobacco use were associated with worse bowel function and total dose and higher BMI was associated with late gastrointestinal toxicity (grade 2 or more on Radiation Therapy Oncology Group/Common Toxicity Criteria for Adverse Events scale) (22).
EORTC QLQ-PRT20 questionnaire, unlike the specific pathology modules of the EORTC, is focused on QoL related to side effects and is effective in detecting intestinal symptoms related to radiotherapy. In addition, it is able to identify changes in the symptoms of patients, proving to be adequate in the evaluation of acute changes after pelvic radiotherapy (9). This study was able to detect worsening of symptoms of fecal urgency and leakage, data that are usually underestimated in the assessment of quality of life.
Despite the changes found in the patients' symptoms, it was not possible to identify decrease of the overall QoL in this analysis. Hinz et al. assessed the QoL of 2059 cancer patients using the EORTC QLQ-C30 questionnaire. The overall QoL of patients was similar to that found in the general population when compared by age and sex, although the specific scores related to function and symptoms demonstrate a significant decrease in QoL. These findings may be related to the hypothesis that people who are experiencing difficult circumstances tend to report states of greater well-being. The explanations found can be defense and adaptation mechanisms, which are more related to global aspects of QoL (6).
This study has several limitations. First, we have analyzed a small sample size. Second, the heterogeneity of the sample, with a predominance of male participants and diagnosis of prostate cancer, may interfere with the analysis of the results. Finally, although the EORTC QLQ-PRT20 questionnaire is provided with the translation into Portuguese (Brazil) by EORTC-QLG, validation in Portuguese was not performed in the phase IV study published in 2018. Failure to perform cross-cultural adaptation and validation of the questionnaire for the Portuguese language (Brazil) can influence the interpretation of the questions by the study participants, impacting in quality of life scores.