Inconsistencies in assessment of pain endpoints in radiotherapy for painful tumors: Analysis of original articles in the Green and Red Journals.

BACKGROUND AND PURPOSE: Consistent assessment of the pain response is essential for adequately comparing treatment efficacy between studies. We studied the assessment of pain endpoints in radiotherapy for painful bone metastases (PBMs) and painful non-bone-metastasis tumors (PNTs). MATERIAL AND METHODS: We performed a literature search in the Green (Radiotherapy and Oncology) and Red (International Journal of Radiation Oncology * Biology * Physics) Journals for full-length original articles published between 2009 and 2018. We only included articles that assessed palliation of tumor-related pain after radiotherapy. The data obtained included the definitions of pain response and assessment of non-index pain (pain other than that related to the irradiated tumors). RESULTS: Among the 1812 articles identified using the journals' search function, 60 were included in the analysis. Thirty percent of the PBM articles and approximately half of the PNT articles did not report on analgesic use. Among the prospective studies, 68% of the articles on PBMs and 10% of the articles on PNTs used the International Consensus Endpoint. The PBM articles published in 2014-2018 utilized the International Consensus Endpoint more frequently than those published in 2009-2013 (p = 0.049). No articles reported information on non-index pain. CONCLUSIONS: After the initial publication of the International Consensus Endpoint, the frequency of its use appears to have risen in PBM research; however, its use in PNT studies has been considerably limited. The International Consensus Endpoint should be consistently utilized in future studies on radiotherapy for painful tumors. Since none of the journal articles had investigated non-index pain, this issue may also needs to be addressed.

Assessment of sexual function in Japanese men with prostate cancer undergoing permanent brachytherapy without androgen deprivation therapy: Analysis from the Japanese Prostate Cancer Outcome Study of Permanent Iodine-125 Seed Implantation database.

OBJECTIVES: To evaluate male sexual function in Japanese prostate cancer patients undergoing permanent brachytherapy without endocrine treatment, using quality of life measures of the Expanded Prostate Cancer Index Composite. METHODS: A total of 482 patients were selected as analysis subjects from the nationwide database for the Japanese Prostate Cancer Outcome Study of Permanent Iodine-125 Seed Implantation. The patients were asked to complete the Expanded Prostate Cancer Index Composite questionnaires before and at 3, 12, 24, and 36 months after the permanent brachytherapy. Changes in their responses were analyzed, and any association of the outcomes was investigated. Furthermore, changes over time in their answers to Q18 (usual quality of your erections) were analyzed. RESULTS: A total of 72 patients (14.9%) had received external beam radiation. A total of 68 patients (14.1%) had taken any 5-phosphodiesterase inhibitor medications. Regarding Q18, 232 patients (48.2%) selected either "There was no sexual activity" or "There was no desire for erection" before receiving permanent brachytherapy. Of all the 482 patients, sexual function was preserved in 138 patients (28.7%) 3 years after permanent brachytherapy. Overall satisfaction has significantly improved without regard for the deterioration of sexual function. Significant factors for maintaining sexual activity were patient age and sexual activity before permanent brachytherapy. CONCLUSIONS: In Japanese patients undergoing permanent brachytherapy alone for prostate cancer, the sexual function is not well preserved. However, decreased sexual function does not seem to represent a major factor determining patients' overall satisfaction. These findings might be peculiar to Japanese patients, in whom elderly subjects account for the majority.

Impact of MRI-based postimplant dosimetric assessment in prostate brachytherapy using contrast-enhanced T1-weighted images.

PURPOSE: To compare contrast-enhanced T1-weighted (CE-T1WI) magnetic resonance imaging (MRI) with computed tomography (CT) for postimplant dosimetry and seed recognition in prostate brachytherapy. METHODS AND MATERIALS: A total of 245 patients who received (125)I prostate brachytherapy with or without external beam radiotherapy were enrolled. For postimplant analysis, CT and MRI scans were obtained at 1 month after seed implantation. For MRI-based dosimetry, T2-weighted images were fused with the CE-T1WI; the prostate was delineated on the T2-weighted images, and the seed detection was performed manually on the CE-T1WI. In CT-based dosimetry, the seed detection was essentially performed automatically. The dosimetric results obtained by MRI-based and CT-based dosimetry were compared. RESULTS: The mean prostate D(90) (the minimum dose received by 90% of the prostate volume) estimated by MRI-based and CT-based dosimetry were 113% and 115%, respectively, with no significant difference. The mean prostate V(100) (the percent volume of the postimplant prostate receiving 100% of the prescribed dose) estimated by MRI-based and CT-based dosimetry were 95.2% and 95.8%, respectively, again with no significant difference. The mean prostate V(150) (the percent volume of the postimplant prostate receiving 150% of the prescribed dose) estimated by MRI-based and CT-based dosimetry were 52.8% and 57.0%, respectively (p<0.01). In all of the 35 patients (14%) in whom the MRI-based V(150) were at least 10% lower than the CT-based results, the seed detection by CT-based dosimetry was overestimated in highly seed-clustered areas or in the areas close to calcifications because of reconstruction artifacts in CT images. CONCLUSIONS: MRI-based dosimetry using CE-T1WI appears to be acceptable. Our results suggest that MRI-based dosimetry is a practical method for estimation of the higher dose distribution, especially if seeds are clustered together or when they are close to calcifications.

Evaluation of the dosimetric parameters for 125I brachytherapy determined in prostate medium using CT images.

In the present study, the prostate medium determined from the CT images of 149 patients was developed. The dosimetric parameters such as Λ, g(L)(r) and F(r, θ) used in TG-43U1-based calculation for an iodine-125 ((125)I) brachytherapy-source were examined using Monte Carlo code Geant4. Clinical dosimetry parameters such as the D(90) were evaluated among a subgroup of 50 randomly selected patients who had been treated with permanent brachytherapy between January 2008 and December 2008 at the Tokyo Medical Center. The results show a slight difference in the dose rate constant Λ (within 1.0%). The radial dose function g(L)(r) exhibits a prominent difference in the region over 3 cm, and this difference is maintained within 2.9% in the region close to the source. The calculated values of F(r, θ) for the prostate medium were similar to values for water (within 1%), except in the longitudinal axis. A comparison of D(90) values shows a systematic dose overestimation of 2.8 ± 0.7 Gy in water, where the distribution of the differences can be seen with a spread of 1.8 ± 0.3% compared to that in prostate medium. It was concluded that the introduction of any kind of tissue correction for the TG-43U1-based calculation was not necessary to allow for the differences in elemental compositions and densities between water and prostate medium. PACS number: 87.00.00; 87.55.dk; 87.55.K-; 87.56.B-.