Fewer systematic prostate core biopsies in clinical stage T1c prostate cancer leads to biochemical recurrence after brachytherapy as monotherapy

BACKGROUND

After brachytherapy, fewer prostate biopsy cores at diagnosis can underestimate the pathological characteristics of prostate cancer (PCa) with lower concordance, resulting in improper treatment, particularly in patients with low-risk nonpalpable cT1c PCa. The aim of this study was to assess the relationship between the number of biopsy cores at diagnosis and long-term clinical outcomes after brachytherapy for cT1c PCa.

METHODS

We reviewed 516 patients with localized cT1c PCa with Gleason scores of 3 + 3 = 6 or 3 + 4 = 7 who underwent brachytherapy as monotherapy without hormonal therapy between January 2005 and September 2014 at our institution. Clinical staging was based on the American Joint Committee on Cancer manual for staging. Thus, the cT1c category is based solely on digital rectal examination. The primary outcome was biochemical recurrence (BCR). Based on the optimized cutoff value for biopsy core number obtained from receiver operating characteristic analysis, patients were divided into the biopsy cores ≤8 (N = 123) and ≥9 (N = 393) groups. The BCR-free survival rate was compared between the groups. Prognostic factors for BCR were evaluated, including age, initial prostate-specific antigen (PSA) level, Gleason score, positive core rate, PSA density, prostate magnetic resonance imaging findings, and biopsy core number.

RESULTS

The median patient age was 66.0 years (interquartile range [IQR]: 61.0-71.0 years), and the median follow-up time was 11.1 years (IQR: 9.5-13.3 years). The median number of core biopsies was 12 (IQR: 9-12). The area under the curve was 0.637 (95% confidence interval [CI]: 0.53-0.75), and the optimal biopsy core cutoff value for BCR prediction was 8.5 (sensitivity = 43.5%, specificity = 77.1%). Although fewer patients had Gleason scores of 3 + 4 = 7 (19/123 [15%] vs. 125/393 [32%], p < 0.02) in the biopsy cores ≤8 group, the 10-year BCR-free survival rate was significantly lower in the biopsy cores ≤8 group than in the biopsy cores ≥9 group (93.8% vs. 96.3%, p < 0.05). Multivariate analysis revealed that a lower biopsy core number (hazard ratio: 0.828, 95% CI: 0.71-0.97, p < 0.03) and a Gleason score of 3 + 4 = 7 (hazard ratio: 3.26, 95% CI: 1.37-7.73, p < 0.01) significantly predicted BCR.

CONCLUSIONS

A low number of prostate core biopsies results in worse BCR-free survival after brachytherapy as monotherapy in patients with cT1c PCa.

Trimodality Therapy With Iodine-125 Brachytherapy, External Beam Radiation Therapy, and Short- or Long-Term Androgen Deprivation Therapy for High-Risk Localized Prostate Cancer: Results of a Multicenter, Randomized Phase 3 Trial (TRIP/TRIGU0907)

PURPOSE

This phase 3 randomized investigation was designed to determine whether 30 months of androgen deprivation therapy (ADT) was superior to 6 months of ADT when combined with brachytherapy and external beam radiation therapy (EBRT) for localized high-risk prostate cancer.

METHODS AND MATERIALS

This study was conducted at 37 hospitals on men aged 40 to 79 years, with stage T2c-3a, prostate-specific antigen >20 ng/mL, or Gleason score >7, who received 6 months of ADT combined with iodine-125 brachytherapy followed by EBRT. After stratification, patients were randomly assigned to either no further treatment (short arm) or 24 months of adjuvant ADT (long arm). According to the Phoenix definition of failure, the primary endpoint was the cumulative incidence of biochemical progression. Secondary endpoints included clinical progression, metastasis, salvage treatment, disease-specific mortality, overall survival, and grade 3+ adverse events. An intention-to-treat analysis was conducted using survival estimates determined using competing risk analyses.

RESULTS

Of 332 patients, 165 and 167 were randomly assigned to the short and long arms, respectively. The median follow-up period was 9.2 years. The cumulative incidence of biochemical progression at 7 years was 9.0% (95% CI, 5.5-14.5) and 8.0% (4.7-13.5) in the short and long arms, respectively (P = .65). The outcomes of secondary endpoints did not differ significantly between the arms. Incidence rates of endocrine- and radiation-related grade 3+ adverse events for the short versus long arms were 0.6 versus 1.8% (P = .62) and 1.2 versus 0.6% (P = .62), respectively.

CONCLUSIONS

Both treatment arms showed similar efficacy among selected populations with high-risk features. The toxicity of the trimodal therapy was acceptable. The present investigation, designed as a superiority trial, failed to demonstrate that 30-month ADT yielded better biochemical control than 6-month ADT when combined with brachytherapy and EBRT. Therefore, a noninferiority study is warranted to obtain further evidence supporting these preliminary results.

Current status and issues with the dosimetric assay of iodine-125 seed sources at medical facilities in Japan: a questionnaire-based survey†

In conducting dosimetric assays of seed sources containing iodine-125 (125I), several major guidelines require the medical physicist to verify the source strength before patient treatment. Japanese guidelines do not mandate dosimetric assays at medical facilities, but since 2017, three incidents have occurred in Japan wherein seeds with incorrect strengths were delivered to medical facilities. Therefore, this study aimed to survey the current situation and any barriers to conducting the dosimetric assay of iodine-125 seeds at medical facilities in Japan. We conducted a questionnaire-based survey from December 2020 to April 2021, to examine whether seed assay and verification of the number of seeds delivered were being performed. We found that only 9 facilities (16%) performed seed assay and 28 (52%) verified the number of seeds. None of the facilities used an assay method that ensured traceability. The reasons for not performing an assay were divided into two categories: lack of resources and legal issues. Lack of resources included lack of instruments, lack of knowledge of assay methods, shorthand, or all of the above, whereas legal issues included the inability to resterilize iodine-125 seeds distributed in Japan and/or purchase seeds dedicated to the assay. Dosimetric assays, including simple methods, are effective in detecting calibration date errors and non-radioactive seeds. The study findings suggest that familiarization of medical personnel with these assay methods and investigation of the associated costs of labor and equipment should be recommended, as these measures will lead to medical reimbursement for quality assurance.

The prognosis of patients with prostate cancer receiving permanent seed implantation stratified by prostate volume: Should we be reluctant to treat with brachytherapy because of a very small prostate (<15 cc)?

PURPOSE

We evaluated the treatment outcomes of different prostate volumes (PVs), <15 cc, 15-20 cc, and > 20 cc, in patients with prostate cancer who underwent permanent seed implantation (PI) ± external beam radiation therapy ± hormone therapy in a national Japanese prospective cohort study (J-POPS).

METHODS AND MATERIALS

Of the 6721 patients in J-POPS from 2005 to 2011, 6652 were included in the analysis population. We categorized the patients into the following three PV groups: <15 cc, 15-20 cc, and > 20 cc. We evaluated the effect of PV on biochemical freedom from failure (bFFF), prostate cancer-specific mortality (PCSM), and all-cause mortality (ACM) using the Phoenix definition and Cox proportional hazard models.

RESULTS

The median follow-up period was 60.0 months. Patients in each PV group was 491 (7.4%), 1118 (16.8%), and 5043 (75.8%), respectively. No difference was observed in bFFF (94.7%, 96.2%, and 95.7%, p = 0.407), PCSM (99.8%, 99.7%, and 99.8%, p = 0.682), and ACM (98.2%, 96.7%, and 97.2%, p = 0.119) at 5 years for each PV group. In univariate and multivariate analyses, PV was not associated with bFFF, PCSM, ACM, or grade 2 toxicity. The percentage of positive biopsies was the single most significant predictor for all treatment outcomes.

CONCLUSIONS

Our results obtained by analyzing a very large Japanese prospective database showed no difference in treatment outcomes according to PV (<15 cc, 15-20 cc, and ˃20 cc). Our study confirmed that PI in small prostates (even < 15 cc) remains an effective treatment option.

Quality of Palliative Radiation Therapy Assessed Using Quality Indicators: A Multicenter Survey

PURPOSE/OBJECTIVE(S)

Clinical practice is not always performed in accordance with guideline recommendations. Quality indicators (QIs) are valuable tools for evaluating the quality of healthcare systems. We sought to identify potential gaps between clinical practice and evidence using QIs previously developed using a modified Delphi method.

MATERIALS/METHODS

We used seven QIs (Table 1) to assess the quality of radiation therapy for bone (BoM) and brain metastases (BrM) at 29 centers; 13 (45%) were academic (12 university hospitals and 1 cancer center) and 16 (55%) were nonacademic hospitals. Compliance rate was calculated as the percentage of patients for whom recommended medical care was conducted. Random effects models were used to estimate pooled compliance rates. Mixed effects models with a Q test were used to compare compliance rates between academic and nonacademic centers.

RESULTS

The estimates of the compliance rates with 95% confidence intervals are presented in Table 1. For BoM-1, the compliance rate was higher in academic hospitals (100% [100-100%]) than in non-academic hospitals (96% [89-100%]) (P = 0.021). For BrM-3, the compliance rate was lower in academic hospitals (92% [81-99%]) than in nonacademic hospitals (100% [98-100%]) (P = 0.016).

CONCLUSION

A quality assessment based on these seven QIs is feasible. Overall, compliance rates were high; however, for BoM-3, the practice remains to be improved in some centers. Based on BoM-4 compliance rates, steroids are infrequently used concurrently with radiation therapy for malignant spinal cord compression. Extended fractionation for BoM was less frequently performed in academic than in nonacademic centers. The initiation of radiation therapy for brain metastases was more frequently delayed in academic than in nonacademic centers.

Health-Related Quality of Life at Five Years for a Randomized Trial of Tri-Modality Therapy with I-125 Brachytherapy, External Beam Radiation Therapy, and Short- vs. Long-Term Androgen Deprivation Therapy for High-Risk Localized Prostate Cancer (TRIP)

PURPOSE/OBJECTIVE(S)

To describe the patient-reported health-related quality of life (HR-QoL) outcomes at five years for a multicenter randomized trial of tri-modality therapy with iodine-125 brachytherapy, external beam radiation therapy (EBRT), and short- versus long-term androgen deprivation therapy (ADT) for high-risk localized prostate cancer (TRIP/TRIGU0907).

MATERIALS/METHODS

A total of 332 men with high-risk prostate cancer were randomized to either 6 months of ADT (n = 165) or 30 months of ADT (n = 167) in conjunction with combined modality radiation therapy. For the HR-QoL assessment, general HR-QoL and disease-specific HR-QoL were measured using the Japanese version of the Medical Outcomes Study 8-items Short-Form Health Survey (SF-8) and the Expanded Prostate Cancer Index Composite (EPIC). Patient-reported outcome questionnaires were filled out before ADT initiation, and five years after. Scores were reported as mean with the standard deviation. QoL end points were assessed as the change between pre and post treatment using paired student t-test. Changes in the International Prostate Symptom Scores (IPSS) score, including total score and subscores, were also evaluated. The study was powered according to the primary endpoint of biochemical progression free survival with HR-QoL as a secondary endpoint. In addition, recovery of testosterone level (300ng/dL or higher) was calculated as the cumulative incidence curve and compared between arms by log-rank test.

RESULTS

The cumulative incidence of biochemical progression, and salvage ADT treatment were not different between the arms. Mean domain scores at baseline were well balanced between the two arms in all HR-QoL. There were no differences in the SF-8 assessment and the total and subscore EPIC assessments between the arms. The average sexual function score was lower in short arm versus long arm; 16.24 versus 20.24 at baseline, but not different at five years, 9.96 versus 7.78 (p = 0.164). There were no significant differences between the arms for the total and subscore IPSS. Significantly higher percentage of patients, 71.7% in the short arm recovered to a normal testosterone level at 6 years after the initiation of ADT compared to 43.2% in long arm (p<0.0001).

CONCLUSION

At five years after ADT initiation, there were no significant differences in all score changes between the two arms with general HR-QoL and disease-specific HR-QoL. Most of HR-QoL returned to baseline level, and sexual function scores were low from baseline in this population. Two-years' adjuvant ADT did not affect HR-QoL at five years, although it significantly retarded testosterone recovery compared to 6 months of hormone therapy.

Evaluation of dose perturbations around iodine-125 seed sources in supplemental external beam prostate radiotherapy

We investigated dose perturbations caused by 125I seeds in patients undergoing supplemental external beam radiotherapy (EBRT) for prostate cancer. We examined two types of nonradioactive seed models: model 6711 and model STM1251. All experiments were performed using a water-equivalent phantom. Radiochromic film was used to measure the dose distributions adjacent to the seeds upstream and downstream of the external beam source. Single and clusters of multiple seeds were placed in slots in a solid water (SW) slab to measure dose perturbations with separate versus dense seed placement at beam energies of 6 or 10 MV. Monte Carlo simulations (MCSs) were also performed to include the theoretical basis against film dosimetry. Distinct patterns of dose enhancement (buildup [BU]) were upstream, and dose reduction (builddown [BD]) were downstream of the radiation source. Model 6711 with lower photon beam energies produced larger dose perturbations of BU and BD than the model STM1251. The results showed the same tendency with different seed placements and beam energies. However, these differences were not observed in the rotational irradiation measurement, which replicated a clinical plan. Dose perturbations around seeds result in dose enhancement and dose reduction with varying impact depending on the photon beam energy and seed type. This has the potential to cancel out these perturbations using multiple beam direction fields.

Definitive radiotherapy consisting of external beam radiotherapy without central shielding and 3D image-guided brachytherapy for patients with cervical cancer: feasibility for Japanese patients and dose-response analyses for local control in the low-dose range

OBJECTIVE

To assess the feasibility of external beam radiotherapy without central shielding in definitive radiotherapy for Japanese patients with cervical cancer.

METHODS

We retrospectively analysed the data of cervical cancer patients treated with definitive radiotherapy consisting of external beam radiotherapy without central shielding and three-dimensional-image-guided brachytherapy.

RESULTS

The study included 167 patients (T1 + 2 = 108, T3 + 4 = 59) from eight Japanese institutions. For three-dimensional-image-guided brachytherapy, intra-cavitary and interstitial brachytherapy was utilized in 33 patients (20%). The median follow-up was 26.6 months (interquartile range, 20-43.2). The maximum rectal D2 (75 Gy)/bladder D2 (90 Gy) constraints were deviated by 6%/10% and 10%/5% for T1 + 2 and T3 + 4, respectively. The 2-year incidence of ≥grade 3 proctitis/cystitis was 4%/1% for T1 + 2 and 10%/2% for T3 + 4. The 2-year local progression-free survival was 89% for T1 + 2 and 82% for T3 + 4. For T1 + 2, the 2-year local progression-free survival for the high-risk clinical target volume D90 ≥ 68 Gy (indicated by receiver operating characteristic analysis; area under the curve = 0.711) was 92% versus 67% for <68 Gy (log-rank; P = 0.019). Cox multivariate analysis indicated that the high-risk clinical target volume D90 was one of independent predictors of local failure (P = 0.0006). For T3 + 4, the 2-year local progression-free survival was 87% for the high-risk clinical target volume <82 cm3 (area under the curve = 0.67) and 43% for ≥82 cm3 (P = 0.0004). Only the high-risk clinical target volume was an independent predictor of local failure (P = 0.0024).

CONCLUSIONS

Definitive radiotherapy consisting of external beam radiotherapy without central shielding and three-dimensional-image-guided brachytherapy was feasible for Japanese patients with cervical cancer. Dose de-escalation from the current global standards is suggested for patients with T1 + 2 disease.

Results of a multicenter, randomized, phase 3 trial of trimodality therapy with I-125 brachytherapy, external beam radiation therapy, and long- versus short-term androgen deprivation therapy for localized high-risk prostate cancer (TRIP/TRIGU0907)

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Background: The TRIP trial was a multicenter, phase 3 randomized investigation designed to determine whether 30 months of androgen deprivation therapy (ADT) was superior to 6 months of ADT when combined with brachytherapy and external beam radiotherapy (EBRT) for localized high-risk prostate cancer. Methods: The trial was done in 37 hospitals in Japan. Men between 40 to 79 years old with stage T2c-3a, or a prostate-specific antigen (PSA) >20 ng/ml or a Gleason score >7 received 6 months of ADT combined with I-125 brachytherapy at a prescription dose of 110 Gy, followed by EBRT of 45 Gy. Patients were randomly assigned either no further treatment (short arm) or 24 months of adjuvant ADT (long arm) after stratification. The primary endpoint was biochemical progression-free survival using the Phoenix definition of failure. Secondary endpoints included clinical progression, metastasis, salvage treatment, disease-specific survival, overall survival, and grade 3 or higher of adverse events. An intention-to-treat analysis was conducted with survival estimates determined using competing risk analyses. Results: Of 332 patients, 165 were randomized to the short and 167 to the long arm. The median follow-up periods were 9.43 and 9.24 years, respectively. 24 patients have died in each arm. The cumulative incidence for biochemical progression in the short vs. long arm were 10.4% (95% confidence interval [CI] 6.62-16.42) vs 9.5% (5.85-15.46) at 9 years, respectively (p=0.647). The cumulative incidences for clinical progression, distant metastases, salvage treatment, and disease-specific mortality events were not significantly different between the two arms. The overall survival rates of the short arm vs long arm were 87.2% (82.13-92.63%) and 85.9% (80.41-91.77%) at 9 years, respectively (p=0.914). Endocrine-related grade 3 morbidity for short arm vs long arm was 0.6% vs 1.8% (p=0.623), and radiation-related grade 3 morbidity was 1.2% vs 0.6% (p=0.622). Conclusions: In localized high-risk prostate cancer, TRIP did not demonstrate the superiority of 30 months vs. 6 months of ADT when combined with brachytherapy and EBRT. These data suggest that ultra-high radiation doses can be combined with a shorter course of ADT without compromising survival. Clinical trial information: UMIN000003992 .

Biochemical outcomes and toxicities in young men with prostate cancer after permanent iodine-125 seed implantation: Prospective cohort study in 6662 patients

PURPOSE

We evaluated the effect of age, <60 and ≥60 years, on biochemical outcomes and toxicities in patients with prostate cancer who underwent permanent seed implantation (PI) ± external beam radiation therapy ± hormone therapy in a national Japanese prospective cohort study (J-POPS).

METHODS AND MATERIALS

The safety and efficacy analyses included 6721 and 6662 patients, respectively. We categorized patients into two age groups: <60 (n = 716) and ≥60 (n = 6,005) years. We used propensity score matching (PSM) to estimate the marginal effect of age on biochemical freedom from failure (bFFF) using a Phoenix definition and Cox proportional hazard models.

RESULTS

The median followup period was 60.0 months. Without PSM, men <60 years demonstrated similar 5-year bFFF (96.3%) compared with men ≥60 years (95.6%; p = 0.576); percent positive biopsies, biologically effective dose, Gleason score, risk classification, and supplemental external beam radiation therapy (p <0.001, <0.001, <0.001, 0.008, and <0.001) were significantly associated with bFFF while age was not (p = 0.576). With PSM, bFFF was not significantly different between age groups (p = 0.664); however, men <60 years showed a significantly lower incidence of declining erectile function, grade ≥2 all urinary toxicities, urinary frequency/urgency, and rectal bleeding (p <0.001, 0.024, 0.031, and 0.010) than men ≥60 years.

CONCLUSIONS

After PI, men <60 years achieved a comparable 5-year biochemical control rate and showed a lower incidence of several toxicities compared to men ≥60 years. This suggests that PI should be an excellent treatment option for men <60 years with prostate cancer.

[Technical Report: Quality Assurance for 125I Seed Sources in Permanent Prostate Brachytherapy]

This technical report provides useful information on the current status and issues of quality control in ¹²⁵I seed source strength measurement for Permanent Prostate Brachytherapy in Japan.With the spread of ¹²⁵I seed brachytherapy, the traceability of source strength measurements with the single-seed assay was established in Japan. This allows medical facilities to measure reference air kerma rate of ¹²⁵I seeds with their own well-type of ionization chamber. However, it is difficult to maintain the traceability chain because the ¹²⁵I reference air kerma rate standards have been hardly utilized by medical facilities so far. Meanwhile, some serious incidents of contamination of the different source strengths and dead seeds were reported in Japan.To address the specific issues in Japan, JASTRO Brachytherapy Subcommittee established a working group (WG) in 2021. The goal of this WG is to investigate the management methods of source strength measurement used in medical facilities, and to discuss the ideal and practicable methods of source management such as verifying the number of seeds and source strength. Initially, a questionnaire survey was conducted to facilities offering ¹²⁵I seed brachytherapy in Japan. Sixty-seven out of 95 facilities responded (response rate 70.5%). This survey revealed that 41% of facilities did not perform either confirmation of the number of seeds or measurement of source strength. There are several reasons why the source strength was not measured in those facilities. For example, ¹²⁵I seeds are provided under the sterilized conditions; quality assurance by source suppliers is reliable; and there is not sufficient staff.The single-seed assay is regarded as an internationally standardized and the most reliable measurement method. Therefore, it is an essential measurement technique to ensure traceability of source strength measurements. However, our survey found that most Japanese facilities do not perform single-seed assays. Meanwhile, some facilities have performed batch assay as an alternative method, in which all of the multiple sources in a batch are measured while loaded into sterilized cartridges. Although the measurement by the batch assay is less accurate than the one by the single-seeded assay, the batch assay does not require re-sterilization of the source and can be performed quickly. It might be useful to detect unexpected errors such as differences in the number of sources and abnormalities in source strength.In this report, we will introduce several methods of source strength measurement that have been implemented in medical facilities. The quality assurance of ¹²⁵I seed sources in prostate interstitial brachytherapy should be provided not only by the source suppliers but also by the medical facilities that use sources to treat patients. We hope that medical facilities will refer to this technical report and use it as an aid to quality assurance in their own facilities.

Phase I/II prospective clinical trial for the hybrid of intracavitary and interstitial brachytherapy for locally advanced uterine cervical cancer

OBJECTIVE

The purposes of this trial were to demonstrate the feasibility and effectiveness of the hybrid of intracavitary and interstitial brachytherapy (HBT) for locally advanced cervical cancer patients in the phase I/II prospective clinical trial.

METHODS

Patients with FIGO stage IB2-IVA uterine cervical cancer pretreatment width of which was ≥5 cm measured by magnetic resonance imaging were eligible for this clinical trial. The protocol therapy included 30-30.6 Gy in 15-17 fractions of whole pelvic radiotherapy concurrent with weekly CDDP, followed by 24 Gy in 4 fractions of HBT and pelvic radiotherapy with a central shield up to 50-50.4 Gy in 25-28 fractions. The primary endpoint of phase II part was 2-year pelvic progression-free survival (PPFS) rate higher than historical control of 64%.

RESULTS

Between October 2015 and October 2019, 73 patients were enrolled in the initial registration and 52 patients proceeded to the secondary registration. With the median follow-up period of 37.3 months (range, 13.9-52.9 months), the 2- PPFS was 80.7% (90% confidence interval [CI]=69.7%-88%). Because the lower range of 90% CI of 2-year PPFS was 69.7%, which was higher than the historical control ICBT data of 64%, therefore, the primary endpoint of this study was met.

CONCLUSION

The effectiveness of HBT were demonstrated by a prospective clinical study. Because the dose goal determined in the protocol was lower than 85 Gy, there is room in improvement for local control. A higher dose might have been needed for tumors with poor responses.

Large volume was associated with increased risk of acute non-hematologic adverse events in the hybrid of intracavitary and interstitial brachytherapy for locally advanced uterine cervical cancer: preliminary results of prospective phase I/II clinical trial

OBJECTIVE

This is the preliminary results of a multi-center prospective clinical trial evaluating the feasibility of the hybrid of intracavitary and interstitial brachytherapy for locally advanced cervical cancer.

METHODS

Patients with FIGO stage IB2, IIA2, IIB, IIIA, IIIB and IVA uterine cervical cancer pretreatment width of which was ≥5 cm measured by MRI were eligible. Protocol therapy consisted of 30-30.6 Gy in 15-17 fractions of whole pelvic radiotherapy concurrent with weekly CDDP, followed by 24 Gy in 4 fractions of hybrid of intracavitary and interstitial and pelvic radiotherapy with central shield up to 50-50.4 Gy in 25-28 fractions. The primary endpoint of phase I part was that the rate of grade ≥ 3 acute non-hematologic adverse events related to hybrid of intracavitary and interstitial would be <10%.

RESULTS

Between October 2015 and October 2019, 74 patients underwent primary registration, with 52 patients eventually proceeding to the secondary registration. The median pretreatment tumor width was 5.7 cm, and FIGO Stages were IB2 10, IIA2 2, IIB 20 and IIIB 20, respectively. The median high-risk clinical target volume D90 was 72.0 Gy (54.8-86.6 Gy, EQD2), rectum D2cc was 53.7 Gy (29.3-80.3 Gy) and bladder D2cc was 69.8 Gy (38.9-84.8 Gy). The rate of grade ≥ 3 non-hematologic adverse events related to hybrid of intracavitary and interstitial was 1.9% (1/52), and 17.3% (9/52) of patients experienced non-hematologic adverse events related to hybrid of intracavitary and interstitial of any grade. In multivariate analysis, high-risk clinical target volume ≥ 35 ml was associated with an increased risk of any grade of acute non-hematologic adverse events related to hybrid of intracavitary and interstitial (P = 0.036).

CONCLUSION

The feasibility and reproducibility of hybrid of intracavitary and interstitial were demonstrated from a multi-center prospective clinical trial.

Radiation dose rate variations in different measurement scenarios after prostate 125I brachytherapy

PURPOSE

This study aimed to directly compare different measurement scenarios using a supplemental radiation exposure measurement data set.

MATERIALS AND METHODS

Two sets of measurement scenarios comparing different body postures, such as standing and chair sitting positions, and different measurement directions, such as anterior and posterior directions, were assessed for radiation dose rate variations in this study at the Tokyo Medical Center, Japan. The estimated precaution time for holding children in the spoon position while sitting was also calculated.

RESULTS

Different radiation dose rate measurement scenarios showed different variation tendencies. Radiation dose rate measurement showed higher mean values of measured radiation dose tendency in the standing position than in the sitting positions. The measurement from the anterior direction showed a slightly lower tendency than that from the posterior direction. Assuming a dose limit of 1 mSv, the precaution time calculated for children being held in the spoon position for a certain duration every day was 51.5 (range, 12.5-152.2) minutes.

CONCLUSIONS

Our study presented a supplemental radiation exposure measurement data set and directly compared different measurement scenarios. Several trends in radiation exposure variations were found in the measurement scenarios at different body postures and different measurement directions. Our study data set could be a useful source of concrete information regarding radiation safety and contribute to the review and revision of public guidance in the future.

Prognostic Value of Epithelial Cell Adhesion Molecules in T1-2N0M0 Glottic Cancer

OBJECTIVE

This is an ancillary study of a multi-institutional randomized non-inferiority phase III trial of accelerated fractionation (AF) versus standard fractionation (SF) radiation therapy for T1-2N0M0 glottic cancer (JCOG0701). Biopsy specimens of tumors from the patients enrolled in the JCOG0701 are collected and the association between clinical outcomes and histopathologic features such as expression of epithelial cell adhesion molecule (EpCAM), p53, and p16 were investigated.

METHODS

Five slices of undyed slides from biopsy specimens were sent to the National Cancer Center Hospital and all the specimens were assessed for the expression of EpCAM, p53, and p16. The primary objective was to investigate the association between 3-year progression-free survival (PFS) and expression of EpCAM, p53, and p16.

RESULTS

A total of 88 out of 370 patients were enrolled in this ancillary study. The 3-year PFS for tumors with strong expression of EpCAM was 70.6% (95% CI 43.1%-86.6%), while that of tumors without strong expression of EpCAM was 77.5% (95% CI 65.9%-85.5%) with no remarkable difference between groups (P = .67). Likewise, there was no significant difference in 3-year PFS between tumors regardless of p53 or p16 status. However, in a subgroup analysis for 17 patients with a strong expression of EpCAM, AF showed better 3-year PFS than SF (100% vs 54.5%, P = .07).

CONCLUSIONS

From the current study, it could not be concluded that EpCAM, p16, and p53 were prognostic factors for early-stage glottic cancer after primary radiation therapy. AF might be an appropriate fractionation for tumors with a strong expression of EpCAM.

LEVEL OF EVIDENCE

3 Laryngoscope, 131:1522-1527, 2021.

Index and Nonindex Pain Endpoints in Radiation Therapy for Painful Tumors: A Secondary Analysis of a Prospective Observational Study

Purpose

Improving pain interference in daily activities, rather than mere pain reduction, is a desirable endpoint for palliative radiation therapy. The association between pain response and pain interference has been studied almost exclusively in patients with painful bone metastases (PBMs), whereas nonindex pain has scarcely been explored in palliative radiation therapy. We investigated whether index and nonindex pain endpoints are associated with pain interference changes in patients with both PBMs and painful non-bone-metastasis tumors (PNTs).

Methods and Materials

Brief pain inventory data collected at baseline and at 2 months post-treatment were used to calculate differences in pain interference scores. Pain response in terms of the index pain was assessed using the international consensus endpoint. Patients were diagnosed with predominance of other pain (POP) if nonindex pain of malignant or unknown origin was present and had a greater pain score than the index pain.

Results

Of 302 patients, 127 (42%) had PBMs and 175 (58%) had PNTs. The median pain interference score, which is based on the mean of the 7 subscale items, decreased to a greater extent among responders than among nonresponders (PBM group: –3.43 vs –0.57 [P = .005]; PNT group: –2.43 vs –0.29 [P < .001]). Moreover, patients without POP experienced a greater reduction in their median pain interference score than did those with POP (PBM group: –2.71 vs +0.43 [P = .004]; PNT group: –2.00 vs +1.57 [P = .007]). The Jonckheere-Terpstra test showed a significant trend across 4 pain response categories in patients with PBMs and those with PNTs (P < .001 for both).

Conclusions

The index and nonindex pain endpoints were positively and negatively associated with improvement in pain interference, respectively. There was no apparent difference between patients with PBMs and PNTs in terms of the associations of these endpoints with pain interference.

Effect of adding androgen deprivation therapy to permanent iodine-125 implantation with or without external beam radiation therapy on the outcomes in patients with intermediate-risk prostate cancer: A propensity score-matched analysis

PURPOSE

The purpose of the study was to evaluate the effect of adding androgen deprivation therapy (ADT) to brachytherapy with or without external beam radiation therapy on oncological outcomes in prostate cancer.

METHODS AND MATERIALS

Overall, 1,171 patients with intermediate-risk prostate cancer treated with brachytherapy with or without external beam radiation therapy with or without ADT between 2003 and 2013 were identified. Propensity score matching was used to counter biases between the ADT and non-ADT groups. The biochemical failure-free rate (bFFR), local recurrence-free rate, and overall survival rate were evaluated using Kaplan-Meier curves, and predictors were identified using Cox proportional hazards regression models.

RESULTS

After propensity score matching, 405 patients were included in each group. The median followup duration was 9.1 years; the median ADT duration was 6 months. In the ADT versus non-ADT groups, the 9-year bFFR, local recurrence-free rate, and overall survival rate were 93.4% versus 87.8% (p = 0.016), 96.9% versus 98.1% (p = 0.481), and 88.1% versus 90.4% (p = 0.969), respectively. On multivariate analyses, Gleason score (hazard ratio [HR]: 2.52, 95% confidence interval [CI]: 1.58-4.03) and ADT use (HR: 0.55, 95% CI: 0.34-0.89) were associated with biochemical failure. Supplemental external beam radiation therapy use (HR: 0.38, 95% CI: 0.16-0.91) was associated with lower local recurrence rates. Age (HR: 1.12, 95% CI: 1.08-1.16) and comorbidities (HR: 1.56, 95% CI: 1.04-2.34) were associated with all-cause mortality.

CONCLUSIONS

A risk-benefit assessment between bFFR improvement and the potential side effects of adding ADT to brachytherapy-based radiotherapy is warranted before incorporating ADT as routine practice.

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

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The frequency of use of the ICT has risen in research for PBMs.

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The frequency of the ICT use has been considerably limited for PNTs.

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None of the journal articles had investigated non-index pain.

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.

Intracardiac metastasis from unknown uterine cervical cancer with severe thrombocytopenia

INTRODUCTION

Cardiac metastasis is relatively common in malignant neoplasms, such as lung cancers, breast cancers, melanomas, lymphomas, and leukemias. In contrast, cardiac metastasis of uterine cervical cancer, solitary metastasis to the heart, and tumors inducing severe thrombocytopenia are rare.

CASE REPORT

The present patient was a 52-year-old female who was diagnosed with a solitary cardiac tumor prior to uterine cervical cancer and presented with severe thrombocytopenia. Our case had two remarkable aspects: 1) successful treatment under the condition of severe thrombocytopenia in association with the presence of a cardiac tumor, and survival without recurrence of the carcinoma one year after surgery; and 2) a solitary cardiac metastatic tumor larger than the primary uterine cervix carcinoma.

COMMENT

we report an extremely rare case of solitary cardiac metastasis of uterine cervical cancer, which wassuccessfully treated. One year after cardiac surgery, the patient is alive without recurrence of the carcinoma.

Results of a multi-institutional, randomized, non-inferiority, phase III trial of accelerated fractionation versus standard fractionation in radiation therapy for T1-2N0M0 glottic cancer: Japan Clinical Oncology Group Study (JCOG0701)

Background

We assessed the non-inferiority of accelerated fractionation (AF) (2.4 Gy/fraction) compared with standard fractionation (SF) (2 Gy/fraction) regarding progression-free survival (PFS) in patients with T1-2N0M0 glottic cancer (GC).

Patients and methods

In this multi-institutional, randomized, phase III trial, patients were enrolled from 32 Japanese institutions. Key inclusion criteria were GC T1-2N0M0, age 20-80, Eastern Cooperative Oncology Group performance status of 0-1, and adequate organ function. Patients were randomly assigned to receive either SF of 66-70 Gy (33-35 fractions), or AF of 60-64.8 Gy (25-27 fractions). The primary end point was the proportion of 3-year PFS. The planned sample size was 360 with a non-inferiority margin of 5%.

Results

Between 2007 and 2013, 370 patients were randomized (184/186 to SF/AF). Three-year PFS was 79.9% (95% confidence interval [CI] 73.4-85.4) for SF and 81.7% (95% CI 75.4-87.0) for AF (difference 1.8%, 91% CI-5.1% to 8.8%; one-sided P = 0.047 > 0.045). The cumulative incidences of local failure at 3 years for SF/AF were 15.9%/10.3%. No significant difference was observed in 3-year overall survival (OS) between SF and AF. Grade 3 or 4 acute and late toxicities developed in 22 (12.4%)/21 (11.5%) and 2 (1.1%)/1 (0.5%) in the SF/AF arms.

Conclusion

Although the non-inferiority of AF was not confirmed statistically, the similar efficacy and toxicity of AF compared with SF, as well as the practical convenience of its fewer treatment sessions, suggest the potential of AF as a treatment option for early GC.

Clinical trials registration

UMIN Clinical Trial Registry, number UMIN000000819.

Biochemical outcomes and predictive factors by risk group after permanent iodine-125 seed implantation: Prospective cohort study in 2,316 patients

PURPOSE

To evaluate the biochemical freedom from failure (bFFF) by risk group and treatment modality and the predictive factors of bFFF by risk group in patients with prostate cancer undergoing permanent seed implantation (PI) with or without external beam radiation therapy (EBRT) in a nationwide prospective cohort study (Japanese Prostate Cancer Outcome Study of Permanent Iodine-125 [I-125] Seed Implantation) in Japan during the first 2 years.

METHODS AND MATERIALS

The analyses included 2,316 participants in 42 institutions; bFFF was evaluated using the Phoenix definition and calculated using the Kaplan-Meier method, and the Cox proportional hazards model was used to identify the factors associated with bFFF.

RESULTS

Median followup period was 60.0 months. The 5-year bFFF rates in all patients, 1,028 low-risk patients, 1,114 intermediate-risk patients, and 133 high-risk patients were 93.6%, 94.9%, 92.7%, and 91.1%, respectively. The 5-year bFFF rates in the PI group and EBRT combination therapy group were 93.7% and 93.3%, respectively. In a multivariate analysis, younger age, higher Gleason score (GS), higher percent positive biopsies (%PB), and lower prostate V₁₀₀ (p = 0.0012, 0.0030, 0.0026, and 0.0368) in all patients; younger age, higher pretreatment prostate-specific antigen, and lower prostate V₁₀₀ (p = 0.0002, 0.0048, and 0.0012) in low-risk patients; higher GS, higher %PB, and no hormonal treatment (p = 0.0005, 0.0120, and 0.0022) in intermediate-risk patients; and higher GS and higher %PB (p = 0.0329 and 0.0120) in high-risk patients were significantly associated with bFFF.

CONCLUSIONS

PI with or without EBRT resulted in excellent short-term biochemical outcomes in all risk groups, especially in high-risk patients. Age, pretreatment prostate-specific antigen, and prostate V₁₀₀ in low-risk patients; GS, %PB, and hormonal treatment in intermediate-risk patients; and GS and %PB in high-risk patients were independently affected bFFF.

Variability of treatment planning of seed implantation: A Japanese multicenter simulation study

PURPOSE

This multicenter study was conducted to evaluate the current variability of treatment planning of seed implantation in Japanese centers and the feasibility of two virtual trials.

METHODS AND MATERIALS

Two types of contour data were sent to 12 radiation oncologists with a request letter that asked them to make treatment plans on the data in the same manner as in their own practice. Five of the 12 radiation oncologists were asked to participate in the two virtual trials in which the D90 (dose to the hottest 90% of prostate volume) was 1) required to be set at just 180 Gy and 2) increased as much as possible without violating other limitations.

RESULTS

A relatively high dose with a small deviation was irradiated to the prostate in Japanese centers (mean D90 = 188 Gy; SD = 10 Gy). In the virtual trials, all five physicians could achieve 180 Gy for the D90 with a very small deviation, although the urethral dose showed relatively large deviations. Dose escalation without increase of urethral dose or V150 was difficult, although the rectum could be spared by most of the physicians.

CONCLUSION

Our study showed a relatively high dose with a small deviation was prescribed to the prostate in Japanese centers. Consolidated protocols such as D90 = 180 Gy could be available for future trials. Meanwhile, our study suggested that some cautions might be needed for urethral dose and the V150, even when a relatively low D90 was requested.

Predictive factors of rectal toxicity after permanent iodine-125 seed implantation: Prospective cohort study in 2339 patients

PURPOSE

To evaluate the incidence and the associated factors of rectal toxicity in patients with prostate cancer undergoing permanent seed implantation (PI) with or without external beam radiation therapy (EBRT) in a nationwide prospective cohort study in Japan (J-POPS) during the first 2 years.

METHODS AND MATERIALS

A total of 2,339 subjects were available for the analyses. Rectal toxicity was evaluated using the National Cancer Institute Common Terminology Criteria for Adverse Events version 3.0.

RESULTS

The 3-year cumulative incidence for grade ≥2 rectal toxicity was 2.88%, 1.76%, and 6.53% in all subjects, PI group and EBRT combination therapy group, respectively. On multivariate analysis, among all subjects, grade ≥2 rectal toxicity was associated with rectal volumes receiving 100% of the prescribed dose (R₁₀₀; p < 0.0001) and EBRT combination therapy (p = 0.0066). R₁₀₀ in the PI group (p = 0.0254), and R₁₀₀ (p = 0.0011) and interactive planning (p = 0.0267) in the EBRT combination therapy group were also associated with grade ≥2 toxicity. The 3-year cumulative incidence of grade ≥2 rectal toxicity was 3.80% and 1.37% for R₁₀₀ ≥ 1 mL and R₁₀₀ < 1 mL, respectively, in the PI group (p = 0.0068), and 14.09% and 5.52% for R₁₀₀ ≥ 1 mL and R₁₀₀ < 1 mL, respectively, in the EBRT combination therapy group (p = 0.0070).

CONCLUSIONS

Rectal toxicity was relatively rare in this study compared with previous reports. For Japanese prostate cancer patients, R₁₀₀ < 1 mL in both PI and EBRT combination therapy groups and interactive planning in EBRT combination therapy group may be effective in decreasing the incidence of rectal toxicity.

Prospective study of direct radiation exposure measurements for family members living with patients with prostate (125)I seed implantation: Evidence of radiation safety

PURPOSE

To broaden the current understanding of radiation exposure and risk and to provide concrete evidence of radiation safety related to (125)I seed implantation.

METHODS AND MATERIALS

Direct radiation exposure measurements were obtained from dosimeters provided to 25 patients who underwent (125)I seed implantation, along with their family members. The estimated lifetime exposure dose and the precaution time for holding children near the patient's chest were calculated in two study periods.

RESULTS

During the first and second study period, the mean estimated lifetime exposure doses were, respectively, 7.61 (range: 0.45, 20.21) mSv and 6.84 (range: 0.41, 19.20) mSv for patients, and 0.19 (range: 0.02, 0.54) mSv and 0.25 (range: 0.04, 1.00) mSv for family members. The mean ratios of first and second period measurements were 1.05 (range: 0.44, 3.18) for patients and 1.82 (range: 0.21, 7.04) for family members. The corresponding absolute differences between first and second period measurements were -0.77 (range: -11.40, 7.63) mSv and 0.06 (range: -0.26, 0.79) mSv, respectively. Assuming a dose limit of 1 mSv, the precaution times for holding a child every day of the first and second periods were 250.9 (range: 71.3, 849.4) min and 275.2 (range: 75.0, 883.4) min, respectively. Assuming a dose limit of 0.5 mSv, the corresponding precaution times were 179.0 (range: 35.6, 811.5) min and 178.9 (range: 37.5, 1131.8) min, respectively.

CONCLUSIONS

Our study demonstrated low radiation exposures to family members of patients undergoing (125)I prostate implantation. It was clear that (125)I seed implantation did not pose a threat to the safety of family members.