Dose comparison of robustly optimized intensity modulated proton therapy (IMPT) vs IMRT and VMAT photon plans for testicular seminoma.

BACKGROUND: Patients with stage II seminoma have traditionally been treated with photons to the retroperitoneal and iliac space, which leads to a substantial dose bath to abdominal and pelvic organs at risk (OAR). As these patients are young and with excellent prognosis, reducing dose to OAR and thereby the risk of secondary cancer is of utmost importance. We compared IMPT to opposing IMRT fields and VMAT, assessing dose to OAR and both overall and organ-specific secondary cancer risk. MATERIAL AND METHODS: A comparative treatment planning study was conducted on planning CT-scans from ten patients with stage II seminoma, treated with photons to a 'dog-leg' field with doses ranging from 20 to 25 Gy and a 10 Gy sequential boost to the metastatic lymph node(s). Photon plans were either 3-4 field IMRT (Eclipse) or 1-2 arc VMAT (Pinnacle). Proton plans used robust (5 mm; 3.5%) IMPT (Eclipse), multi field optimization with 3 posterior fields supplemented by 2 anterior fields at the level of the iliac vessels. Thirty plans were generated. Mean doses to OARs were compared for IMRT vs IMPT and VMAT vs IMPT. The risk of secondary cancer was calculated according to the model described by Schneider, using excess absolute risk (EAR, per 10,000 persons per year) for body outline, stomach, duodenum, pancreas, bowel, bladder and spinal cord. RESULTS: Mean doses to all OARs were significantly lower with IMPT except similar kidney (IMRT) and spinal cord (VMAT) doses. The relative EAR for body outline was 0.59 for IMPT/IMRT (p < .05) and 0.33 for IMPT/VMAT (p < .05). Organ specific secondary cancer risk was also lower for IMPT except for pancreas and duodenum. CONCLUSION: Proton therapy reduced radiation dose to OAR compared to both IMRT and VMAT plans, and potentially reduce the risk of secondary cancer both overall and for most OAR.

Effect of docetaxel added to bicalutamide in Hormone-Naïve non-metastatic prostate cancer with rising PSA, a randomized clinical trial (SPCG-14).

BACKGROUND: Historically, endocrine therapy was used in a range of scenarios in patients with rising PSA, both as a treatment for locally advanced non-metastatic prostate cancer and PSA recurrence following curative intended therapy. In the present study the objective was to investigate if chemotherapy added to endocrine therapy could improve progression-free survival (PFS). MATERIALS AND METHODS: Patients with hormone-naïve, non-metastatic prostate cancer and rising prostate-specific antigen (PSA), enrolled from Sweden, Denmark, the Netherlands, and Finland, were randomized to long-term bicalutamide (150 mg daily) or plus docetaxel (75 mg/m2, q3w, 8-10 cycles) without prednisone, after stratification for the site, prior local therapy or not, and PSA doubling time. The primary endpoint was 5-year PFS analyzed with a stratified Cox proportional hazards regression model on intention to treat basis. RESULTS: Between 2009 and 2018, a total of 348 patients were randomized; 315 patients had PSA relapse after radical treatment, 33 patients had no prior local therapy. Median follow-up was 4.9 years (IQR 4.0-5.1). Adding docetaxel improved PFS (HR 0.68, 95% CI 0.50-0.93; p = 0.015). Docetaxel showed an advantage for patients with PSA relapse after prior local therapy (HR 0.67, 95% CI 0.49-0.94; p = 0.019). One event of neutropenic infection/fever occurred in 27% of the patients receiving docetaxel. Limitations were slow recruitment, lack of enrolling patients without radical local treatment, and too short follow-up for evaluation of overall survival in patients with PSA relapse. CONCLUSION: Docetaxel improved PFS in patients starting bicalutamide due to PSA relapse after local therapy or localized disease without local therapy. Confirmatory studies of the efficacy of docetaxel in the setting of PSA-only relapse in addition to endocrine therapies may be justified if longer follow-up will show increased metastatic-free survival.

Patterns of relapse and long-term outcome in patients treated with a curative intent for advanced Hodgkin lymphoma.

BACKGROUND: Consolidation radiotherapy for advanced Hodgkin lymphoma (AHL) is controversial. Precise knowledge of the most likely relapse location is crucial for radiotherapy planning. We performed detailed patterns of relapse analyses and evaluated if initial bulky disease, initial 18F-fluoro-deoxy-glucose (FDG)-avidity and/or a residual mass on computed tomography (CT)-scan after chemotherapy are sites with a high risk of relapse. This information could provide guidance for optimal use of radiotherapy in AHL. MATERIAL AND METHODS: We included 133 patients treated with curatively intended chemotherapy for AHL. 23 patients received consolidation radiotherapy. For relapsed patients, imaging from diagnosis, response evaluation, relapse, and any radiotherapy planning, were retrieved and co-registered to determine the exact site(s) of relapse relative to initial site(s), residual mass(es) and to any irradiated volumes. Size and FDG-avidity of initial sites with later relapse, and residual CT-abnormalities after chemotherapy in these sites were registered. Survival analyses were done using the Kaplan-Meier method. RESULTS: Nine (6.8%) patients relapsed, eight in initially involved sites. One relapse was in an initially irradiated site (as well as other sites). Initial bulky disease, high initial FDG-uptake, and/or residual masses on CT-scan after chemotherapy did not predict sites with a high risk of relapse. Overall survival was 79.6% (95% CI, 72.7-86.5%) and 70.6% (95% CI, 62.4-78.8%) at 5 and 10 years, respectively. Time to progression analysis showed 91.8% (95% CI, 86.9-96.7%) and 90.7% (95% CI, 85.4-96.0%) without progression at 5 and 10 years, respectively. CONCLUSION: Current treatment strategies for AHL provide excellent disease control. Neither initial bulk, high initial FDG-uptake, nor a residual CT-abnormality post-chemotherapy seem to indicate sites with a high risk of relapse.

Interobserver delineation uncertainty in involved-node radiation therapy (INRT) for early-stage Hodgkin lymphoma: on behalf of the Radiotherapy Committee of the EORTC lymphoma group.

BACKGROUND AND PURPOSE: In early-stage classical Hodgkin lymphoma (HL) the target volume nowadays consists of the volume of the originally involved nodes. Delineation of this volume on a post-chemotherapy CT-scan is challenging. We report on the interobserver variability in target volume definition and its impact on resulting treatment plans. MATERIALS AND METHODS: Two representative cases were selected (1: male, stage IB, localization: left axilla; 2: female, stage IIB, localizations: mediastinum and bilateral neck). Eight experienced observers individually defined the clinical target volume (CTV) using involved-node radiotherapy (INRT) as defined by the EORTC-GELA guidelines for the H10 trial. A consensus contour was generated and the standard deviation computed. We investigated the overlap between observer and consensus contour [Sørensen-Dice coefficient (DSC)] and the magnitude of gross deviations between the surfaces of the observer and consensus contour (Hausdorff distance). 3D-conformal (3D-CRT) and intensity-modulated radiotherapy (IMRT) plans were calculated for each contour in order to investigate the impact of interobserver variability on each treatment modality. Similar target coverage was enforced for all plans. RESULTS: The median CTV was 120 cm3 (IQR: 95-173 cm3) for Case 1, and 255 cm3 (IQR: 183-293 cm3) for Case 2. DSC values were generally high (>0.7), and Hausdorff distances were about 30 mm. The SDs between all observer contours, providing an estimate of the systematic error associated with delineation uncertainty, ranged from 1.9 to 3.8 mm (median: 3.2 mm). Variations in mean dose resulting from different observer contours were small and were not higher in IMRT plans than in 3D-CRT plans. CONCLUSIONS: We observed considerable differences in target volume delineation, but the systematic delineation uncertainty of around 3 mm is comparable to that reported in other tumour sites. This report is a first step towards calculating an evidence-based planning target volume margin for INRT in HL.

Salvage radiation therapy following radical prostatectomy. A national Danish study.

BACKGROUND: The purpose of this observational cohort study was to evaluate the outcome and prognostic factors following salvage radiotherapy (SRT) in a consecutive national cohort. MATERIAL AND METHODS: Between 2006 and 2010, 259 patients received SRT in Denmark. Patient- and cancer-related characteristics were retrospectively retrieved from patient charts. The primary end point was biochemical progression-free survival (b-PFS). RESULTS: At the end of follow-up, 51% of the patients displayed a prostate-specific antigen (PSA) level <0.1 ng/ml. The three-year b-PFS rate for the total cohort was 57.0%. Nearly half of the patients (44%) received androgen deprivation therapy (ADT) in combination with SRT. Positive surgical tumour margins (p = 0.025) and ADT (p = 0.001) were the only markers independently correlated with b-PFS. In patients who received SRT without ADT, both a pre-SRT PSA level ≤0.5 ng/ml (p = 0.003) and pathological tumour stage T1-T2 (p = 0.036) independently correlated with b-PFS. Moreover, a duration between radical prostatectomy (RP) and SRT ≤29 months (p = 0.035) independently correlated with b-PFS in patients treated with ADT in combination with RT. CONCLUSIONS: In patients treated for biochemical failure after RP, positive surgical tumour margins and PSA levels ≤0.5 ng/mL at the time of SRT were associated with a favourable outcome. Despite less favourable tumour characteristics, patients receiving SRT and ADT demonstrated improved b-PFS, and in particular, patients with PSA levels >0.2 ng/ml benefitted from additional ADT.

Current evidence for moderate and ultra-hypofractionated radiation therapy in prostate cancer: a summary of the results from phase 3 randomised trials.

PROBLEM: A low α/ß ratio for prostate cancer (PCa) compared to surrounding normal tissue theoretically implies therapeutical advantages with hypofractionated treatment. Data from large randomised control trials (RCTs) comparing moderate hypofractionated (MHRT, 2.4-3.4 Gray/fraction (Gy/fx)) and ultra-hypofractionated (UHRT, >5 Gy/fx) with conventionally fractionated radiation therapy (CFRT, 1.8-2 Gy/fx) and the possible clinical implications have been reviewed. MATERIALS AND METHOD: We searched PubMed, Cochrane and Scopus for RCT comparing MHRT/UHRT with CFRT treatment of locally and/or locally advanced (N0M0) PCa. We found six RCTs, which compared different radiation therapy regimes. Tumour control and acute and late toxicities are reported. RESULTS: MHRT was non-inferior to CFRT for intermediate-risk PCa, non-inferior for low-risk PCa and not superior in terms of tumour control for high-risk PCa. Acute toxicity rates were increased compared to CFRT, especially an increase in acute gastrointestinal adverse effects was seen. Late toxicity related to MHRT seems to be comparable. UHRT was non-inferior in terms of tumour control in one RCT, with increased acute toxicity, but with comparable late toxicity. One trial, however, indicated increased late toxicity rates with UHRT. DISCUSSION AND CONCLUSION: MHRT delivers similar therapeutic outcomes compared to CFRT in terms of tumour control and late toxicity for intermediate-risk PCa patients. Slightly more acute transient toxicity could be tolerated in favour of a shorter treatment course. UHRT should be regarded as an optional treatment for patients with low- and intermediate-risk disease applied at experienced centres in concordance with international and national guidelines.

Characteristics of Patients in SPCG-15-A Randomized Trial Comparing Radical Prostatectomy with Primary Radiotherapy plus Androgen Deprivation Therapy in Men with Locally Advanced Prostate Cancer.

Background: There is no high-grade evidence for surgery as primary treatment for locally advanced prostate cancer. The SPCG-15 study is the first randomized trial comparing surgical treatment with radiotherapy. Objective: To describe the baseline characteristics of the first 600 randomized men in the SPCG-15 study. The study will compare mortality and functional outcomes. Design setting and participants: This study is a Scandinavian prospective, open, multicenter phase III randomized clinical trial aiming to randomize 1200 men. Intervention: Radical prostatectomy with or without consecutive radiotherapy (experimental) and radiotherapy with neoadjuvant androgen deprivation therapy (standard of care). Outcome measurements and statistical analysis: Cause-specific survival, metastasis-free survival, overall survival, and patient-reported bowel function, sexual health, and lower urinary tract symptoms were measured. Results and limitations: The distribution of characteristics was similar in the two study arms. The median age was 67 yr (range 45-75 yr). Among the operated men, 36% had pT3a stage of disease and 39% had pT3b stage. International Society of Urological Pathology grades 2, 3, 4, and 5 were prevalent in 21%, 35%, 7%, and 27%, respectively. Half of the men (51%) in the surgery arm had no positive lymph nodes. The main limitation is the pragmatic design comparing the best available practice at each study site leading to heterogeneity of treatment regimens within the study arms. Conclusions: We have proved that randomization between surgery and radiotherapy for locally advanced prostate cancer is feasible. The characteristics of the study population demonstrate a high prevalence of advanced disease, well-balanced comparison groups, and a demography mirroring the Scandinavian population of men with prostate cancer at large. Patient summary: This study, which has recruited >600 men, compares radiotherapy with surgery for prostate cancer, and an analysis at the time of randomization indicates that the study will be informative and generalizable to most men with locally advanced but not metastasized prostate cancer.

Late urinary morbidity and quality of life after radical prostatectomy and salvage radiotherapy for prostate cancer.

OBJECTIVE: There is a paucity of knowledge of long-term urinary morbidity in patients treated for prostate cancer (PCa) with radical prostatectomy (RP) and salvage radiotherapy (SRT). Improved long-term survival calls for heightened awareness of late effects from radiotherapy after RP. The purpose of this study was to assess late urinary morbidity and its potential impact on quality of life (QoL) in patients treated with RP plus SRT compared with patients treated with RP alone. MATERIALS AND METHODS: Long-term morbidity and QoL were evaluated using a cross-sectional design with validated questionnaires in urinary morbidity [Danish Prostatic Symptom Score (DAN-PSS)] and QoL [European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30)]. Included were a total of 227 patients treated with SRT and 192 treated with RP in the periods 2006-2010 and 2005-2007, respectively. RESULTS: Weak stream, straining, frequency and nocturia were significantly more prevalent in patients treated with RP + SRT than in patients treated with RP alone. Patients treated with RP + SRT generally suffered from more severe urinary symptoms. The QoL scores of the two treatment groups were not statistically significantly different, but a high level of urinary morbidity was significantly related to decreased QoL (p = 0.000). CONCLUSIONS: Patients treated with SRT have a higher rate of urinary morbidity than do patients treated with RP alone. Severe urinary morbidity was significantly related to decreased QoL, but did not differ between the two treatment groups.

Neurological Adverse Effects after Radiation Therapy for Stage II Seminoma.

We report 3 cases of patients with testicular cancer and stage II seminoma who developed neurological symptoms with bilateral leg weakness about 4 to 9 months after radiation therapy (RT). They all received RT to the para-aortic lymph nodes with a total dose of 40 Gy (36 Gy + 4 Gy as a boost against the tumour bed) with a conventional fractionation of 2 Gy/day, 5 days per week. RT was applied as hockey-stick portals, also called L-fields. In 2 cases, the symptoms fully resolved. Therapeutic irradiation can cause significant injury to the peripheral nerves of the lumbosacral plexus and/or to the spinal cord. RT is believed to produce plexus injury by both direct toxic effects and secondary microinfarction of the nerves, but the exact pathophysiology of RT-induced injury is unclear. Since reported studies of radiation-induced neurological adverse effects are limited, it is difficult to estimate their frequency and outcome. The treatment of neurological symptoms due to RT is symptomatic.