Survival Outcomes of Radical Prostatectomy Versus Radiotherapy in Intermediate-Risk Prostate Cancer: A NCDB Study

Background

Studies of various prostate cancer patient cohorts found men receiving external-beam radiotherapy (EBRT) had higher mortality than men undergoing radical prostatectomy (RP). Conversely, a recent clinical trial showed no survival differences between treatment groups. We used the National Cancer Data Base (NCDB) to evaluate overall survival in intermediate-risk (T2b-T2c or Gleason 7 [grade group II or III] or prostate-specific antigen 10-20 ng/mL) prostate cancer patients undergoing EBRT with or without androgen deprivation therapy (ADT), RP, or no initial treatment.

Prospective Randomized Phase II Study of Stereotactic Body Radiotherapy (SBRT) vs. Conventional Fractionated Radiotherapy (CFRT) for Chinese Patients with Early-Stage Localized Prostate Cancer

Background: Stereotactic body radiotherapy (SBRT) has potential radiobiologic and economic advantages over conventional fractionated radiotherapy (CFRT) in localized prostate cancer (PC). This study aimed to compare the effects of these two distinct fractionations on patient-reported quality of life (PRQOL) and tolerability. Methods: In this prospective phase II study, patients with low- and intermediate-risk localized PC were randomly assigned in a 1:1 ratio to the SBRT (36.25 Gy/5 fractions/2 weeks) or CFRT (76 Gy/38 fractions/7.5 weeks) treatment groups. The primary endpoint of variation in PRQOL at 1 year was assessed by changes in the Expanded Prostate Cancer Index Composite (EPIC) questionnaire scores and analysed by z-tests and t-tests. Results: Sixty-four eligible Chinese men were treated (SBRT, n = 31; CFRT, n = 33) with a median follow-up of 2.3 years. At 1 year, 40.0%/46.9% of SBRT/CFRT patients had a >5-point decrease in bowel score (p = 0.08/0.28), respectively, and 53.3%/46.9% had a >2-point decrease in urinary score (p = 0.21/0.07). There were no significant differences in EPIC score changes between the arms at 3, 6, 9 and 12 months, but SBRT was associated with significantly fewer grade ≥ 1 acute and 1-year late gastrointestinal toxicities (acute: 35% vs. 87%, p < 0.0001; 1-year late: 64% vs. 84%, p = 0.03), and grade ≥ 2 acute genitourinary toxicities (3% vs. 24%, p = 0.04) compared with CFRT. Conclusion: SBRT offered similar PRQOL and less toxicity compared with CFRT in Chinese men with localized PC.     

The Journey of Radiotherapy Dose Escalation in High Risk Prostate Cancer; Conventional Dose Escalation to Stereotactic Body Radiotherapy (SBRT) Boost Treatments

High risk prostate cancer (HR-PrCa) is a subset of localized PrCa with significant potential for morbidity and mortality associated with disease recurrence and metastasis. Radiotherapy combined with Androgen Deprivation Therapy has been the standard of care for many years in HR-PrCa. In recent years, dose escalation, hypo-fractionation and high precision delivery with immobilization and image-guidance have substantially changed the face of modern PrCa radiotherapy, improving treatment convenience and outcomes. Ultra-hypo-fractionated radiotherapy delivered with high precision in the form of stereotactic body radiation therapy (SBRT) combines delivery of high biologically equivalent dose radiotherapy with the convenience of a shorter treatment schedule, as well as the promise of similar efficacy and reduced toxicity compared to conventional radiotherapy. However, rigorous investigation of SBRT in HR-PrCa remains limited. Here, we review the changes in HR-PrCa radiotherapy through dose escalation, hypo- and ultra-hypo-fractionated radiotherapy boost treatments, and the radiobiological basis of these treatments. We focus on completed and on-going trials in this disease utilizing SBRT as a sole radiation modality or as boost therapy following pelvic radiation.     

Extreme Hypofractionation with SBRT in Localized Prostate Cancer

Prostate cancer is the most commonly diagnosed cancer among men around the world. Radiotherapy is a standard of care treatment option for men with localized prostate cancer. Over the years, radiation delivery modalities have contributed to increased precision of treatment, employing radiobiological insights to shorten the overall treatment time, improving the control of the disease without increasing toxicities. Stereotactic body radiation therapy (SBRT) represents an extreme form of hypofractionated radiotherapy in which treatment is usually delivered in 1–5 fractions. This review assesses the main efficacy and toxicity data of SBRT in non-metastatic prostate cancer and discusses the potential to implement this scheme in routine clinical practice.     

Radiotherapy Quality Assurance for the CHHiP Trial: Conventional Versus Hypofractionated High-Dose Intensity-Modulated Radiotherapy in Prostate Cancer

AimsThe CHHiP trial investigated the use of moderate hypofractionation for the treatment of localised prostate cancer using intensity-modulated radiotherapy (IMRT). A radiotherapy quality assurance programme was developed to assess compliance with treatment protocol and to audit treatment planning and dosimetry of IMRT. This paper considers the outcome and effectiveness of the programme.Materials and methodsQuality assurance exercises included a pre-trial process document and planning benchmark cases, prospective case reviews and a dosimetry site visit on-trial and a post-trial feedback questionnaire.ResultsIn total, 41 centres completed the quality assurance programme (37 UK, four international) between 2005 and 2010. Centres used either forward-planned (field-in-field single phase) or inverse-planned IMRT (25 versus 17). For pre-trial quality assurance exercises, 7/41 (17%) centres had minor deviations in their radiotherapy processes; 45/82 (55%) benchmark plans had minor variations and 17/82 (21%) had major variations. One hundred prospective case reviews were completed for 38 centres. Seventy-one per cent required changes to clinical outlining pre-treatment (primarily prostate apex and base, seminal vesicles and penile bulb). Errors in treatment planning were reduced relative to pre-trial quality assurance results (49% minor and 6% major variations). Dosimetry audits were conducted for 32 centres. Ion chamber dose point measurements were within ±2.5% in the planning target volume and ±8% in the rectum. 28/36 films for combined fields passed gamma criterion 3%/3 mm and 11/15 of IMRT fluence film sets passed gamma criterion 4%/4 mm using a 98% tolerance. Post-trial feedback showed that trial participation was beneficial in evolving clinical practice and that the quality assurance programme helped some centres to implement and audit prostate IMRT.ConclusionOverall, quality assurance results were satisfactory and the CHHiP quality assurance programme contributed to the success of the trial by auditing radiotherapy treatment planning and protocol compliance. Quality assurance supported the introduction of IMRT in UK centres, giving additional confidence and external review of IMRT where it was a newly adopted technique.     

Cost–Utility Analysis of Radiation Treatment Modalities for Intermediate-Risk Prostate Cancer

Introduction: Variable costs of different radiation treatment modalities have played an important factor in selecting the most appropriate treatment for patients with intermediate-risk prostate cancer. Methods: Analysis using a Markov model was conducted to simulate 20-year disease trajectory, quality-adjusted life years (QALYs) and health system costs of a cohort of intermediate-risk prostate cancer patients with mean age of 60 years. Clinical outcomes on toxicity and disease recurrence were measured and a probabilistic sensitivity analysis was performed, varying input parameters simultaneously according to their distributions. Results: Among the six radiation treatment modalities, including conventionally fractionated intensity-modulated radiation therapy (IMRT), hypofractionated IMRT, IMRT combined with high-dose-rate (HDR) brachytherapy, HDR brachytherapy monotherapy, low-dose-rate brachytherapy monotherapy, and stereotactic body radiotherapy (SBRT), SBRT was found to be more cost-effective when compared with LDR-b and other treatment modalities, resulting in an incremental cost–utility ratio of $2985 per QALY. Conclusions: Stereotactic body radiotherapy is the most cost-effective radiation treatment modality in treatment of intermediate-risk prostate cancer, while treatment toxicity and cost data are the key drivers of the cost–utility. Further work is required with long-term follow-up for SBRT.     

常规与后程超分割放疗治疗食管癌的疗效分析

[目的]对常规放疗和后程超分割放疗治疗食管癌的临床疗效进行分析。[方法]将72例食管癌患者分成两组,34例常规组患者采取常规放疗方案,38例观察组患者采取后程超分割放疗方案,治疗结束后随访3年,观察并比较两组的局部控制率、生存率和不良反应。[结果]观察并组治疗后1、2和3年的局部控制率分别为78.95%、65.79%和47.37%,优于常规组（P〈0.05）;观察组治疗后1、2和3年的生存率分别为73.68%、55.26%和39.47%,亦显著优于常规组（P〈0.05）;两组治疗后不良反应比较无显著性差异（P〉0.05）。[结论]后程超分割放疗治疗食管癌的临床疗效显著,提高了局部控制率和生存率,对食管黏膜和肺组织的损伤程度不大,值得临床推广应用。     

Outcomes for Young Men With Localized Intermediate-Risk Prostate Cancer: An Analysis of the NCDB

BackgroundPrimary management of localized, intermediate-risk prostate cancer consists of radical prostatectomy (RP), radiotherapy (RT) with short-course androgen deprivation therapy (ADT), or RT alone. The purpose of this study was to determine if these treatment strategies have equivalent overall survival (OS) in patients < 55 years old with intermediate-risk prostate cancer.Patients and MethodsWe identified 35,134 patients in the National Cancer Data Base with localized intermediate-risk prostate cancer treated with RP, RT + ADT, or RT from 2004 to 2013. Ten-year OS rates were estimated by the Kaplan-Meier method. Adjusted hazard ratios (HR) with 95% confidence intervals (CI) were computed by multivariate Cox regression.ResultsA total of 29,920 patients (85.2%) underwent RP, 1393 (4.0%) RT + ADT, and 3821 (10.9%) RT. Median patient age was 51 years old, and median follow-up was 59.9 months. Ten-year OS was estimated to be 94.2% for RP, 80.7% for RT + ADT, and 85.2% for RT (P < .0001). On multivariate analysis, treatment with RT + ADT or RT was associated with significantly worse OS compared to treatment with RP (RT + ADT HR = 2.06, 95% CI 1.67-2.54, P < .0001; RT HR = 2.0, 95% CI 1.71-2.33, P < .0001). Patients who met all 3 of the intermediate-risk criteria showed worse OS compared to patients who met only one criterion (HR = 1.80; 95% CI, 1.32-2.44; P = .0002).ConclusionRP is significantly more likely than RT + ADT or RT to be used as a primary treatment for young men with localized intermediate prostate cancer. RP was also associated with improved OS compared to RT + ADT and RT.     

Salvage Radiotherapy for Prostate Cancer

For patients experiencing biochemical recurrence in the absence of distant metastasis, salvage radiotherapy (SRT) with or without androgen deprivation therapy (ADT) is currently the only possible curative treatment option. Prostate-specific antigen (PSA) monitoring and the selected use of SRT has some advantages when compared with adjuvant radiotherapy. The most important one is avoidance of a potential overtreatment of patients who would never have disease progression, even in the presence of high-risk pathological features. The identification of a specific PSA cut-off seems to be incorrect. In patients with more adverse pathological features, early SRT administered at the very first sign of a PSA rise granted better disease control. Dose-intensified SRT is feasible and well tolerated with no significant difference in grade 2 or more acute and late toxicity. At least 66 Gy must be given in the salvage setting. ADT has a radio-sensitising effect on the radiotherapy by inhibiting the repair of DNA double-strand breaks. The use of ADT in the salvage setting results in a better oncological outcome. Hormonal therapy is associated with a decrease in quality of life and side-effects depending on the duration of hormone therapy. The oncological benefit of hormone therapy duration depends on their clinical and pathological characteristics. 68-Ga-prostate-specific membrane antigen positron emission tomography-computed tomography is the gold standard in staging prostate cancer patients with biochemical persistence or recurrence after radical prostatectomy. The implementation of 18F-labelled PSMA tracers can provide a further improvement.     

体部立体定向放疗在肺部肿瘤中的应用

摘 要：体部立体定向放疗(stereotactic body radiotherapy,SBRT)是将放射剂量聚集到病灶,几次照射（≤5次）即可达到根治剂量,用立体准确定向的高能射线来杀灭肿瘤。精确定位、精准制导以及严密质控,使高剂量消融肿瘤的同时,危及器官得到保护,也使得SBRT应用更加广泛。老龄化提前到来和低剂量螺旋CT的普及使得早期肺癌的确诊明显增加;因内科基础疾病或多原发而不能手术的肺部病灶,SBRT可提供很高的局部控制率;对可手术病灶,SBRT能达到相似的局部控制率;另外对肺孤立转移瘤,全身联合局部治疗已被普遍接受。全文对SBRT在肺部肿瘤中的研究进展作一综述。     

Cost-effectiveness of Intensity-modulated Radiotherapy in Prostate Cancer

AimsTo compare the costs and effectiveness of intensity-modulated radiotherapy (IMRT) with three-dimensional conformal radiotherapy (3DCRT) for the radical treatment of localised prostate cancer at elevated doses (>70 Gy).Materials and methodsA cost-effectiveness analysis model was developed using clinical effectiveness estimates from a systematic review. The base case analysis assumes equal biochemical survival for IMRT and 3DCRT, but lower frequency of gastrointestinal toxicity for IMRT. The costs of IMRT and 3DCRT were estimated through activity-based costing, incorporating input from radiation oncologists, physicists and treatment planners.ResultsThe delivery of IMRT produced 0.023 more quality-adjusted life-years (QALY) than 3DCRT at an additional cost of $621 (QALY and costs discounted at 5% per year), yielding an incremental cost-effectiveness ratio of $26 768 per QALY gained. The treatment cost of IMRT was $1019 more than 3DCRT, but IMRT resulted in less frequent gastrointestinal toxicity, thus avoiding $402 in the treatment of toxicity. In the scenario that compared a higher dose of IMRT (75.6 Gy) to 3DCRT (68.4 Gy), IMRT improved disease control with equal toxicity incidence, and the IMRT strategy dominated (less costly and more effective). In the base case scenario (no survival difference), the cost-effectiveness of IMRT was most sensitive to the treatment cost difference between IMRT and 3DCRT.ConclusionFor radical radiation treatment (>70 Gy) of prostate cancer, IMRT seems to be cost-effective when compared with an equivalent dose of 3DCRT.     

Moderately Hypofractionated Radiotherapy in Node-positive Prostate Cancer

Aims

Node-positive prostate cancer is a unique subgroup, with varied practice on locoregional treatment. Definitive treatment with hypofractionated radiotherapy has not been widely reported. We have routinely used standard regimens of hypofractionated radiotherapy for node-positive disease and report our results of toxicity, biochemical control and survival.

A Randomized Phase II Trial of Prostate Boost Irradiation With Stereotactic Body Radiotherapy (SBRT) or Conventional Fractionation (CF) External Beam Radiotherapy (EBRT) in Locally Advanced Prostate Cancer: The PBS Trial (NCT03380806)

Standard therapy for high-risk (HR) prostate cancer (PrCa) involves androgen deprivation therapy (ADT) and pelvic conventional fractionation (CF) external beam radiotherapy (EBRT) followed by boost CF-EBRT treatment to prostate for a total of 78 to 80 Gy in 39 to 40 fractions. This is a long and inconvenient treatment for patients. Brachytherapy boost treatment studies indicate that escalation of biological dose of radiotherapy (RT) can improve outcomes in HR-PrCa. However, brachytherapy is an invasive treatment associated with increased toxicity and requires specialized resources. Stereotactic body radiotherapy (SBRT) is a promising, non-invasive alternative to brachytherapy. However, its impact on patient quality of life (QoL) and RT-associated toxicity has not been investigated in a randomized setting. In this study, we investigate SBRT as a boost treatment, following pelvic CF-EBRT, in patients with HR-PrCa treated with ADT. One hundred patients with locally advanced PrCa will be randomized to receive daily CF-EBRT of 45 to 46 Gy in 23 to 25 fractions followed by either daily CF-EBRT of 32 to 33 Gy in 15 to 16 fractions (control arm) or SBRT boost treatment of 19.5 to 21 Gy in 3 fractions (1 fraction per week) (experimental arm). The primary objective of the PBS trial is early bowel and urinary QoL (expanded prostate index composite [EPIC], up to 6 months after RT). This phase II randomized study (PBS) provides an appropriate setting to investigate effectively the impact of SBRT boost on QoL and toxicity in patients with HR-PrCa, before this modality can be compared against the current standard of care in larger phase III protocols.     

Intensity-modulated Radiotherapy in the Treatment of Prostate Cancer

Three-dimensional conformal radiotherapy (3DCRT) as the primary treatment for prostate cancer has improved outcomes compared with conventional radiotherapy, but with an associated increase in toxicity due to radiation effects on the bladder and rectum. Intensity-modulated radiotherapy (IMRT) is a newer method of radiotherapy that uses intensity-modulated beams that can provide multiple intensity levels for any single beam direction and any single source position allowing concave dose distributions and dose gradients with narrower margins than those possible using conventional methods. IMRT is ideal for treating complex treatment volumes and avoiding close proximity organs at risk that may be dose limiting and provides increased tumour control through an escalated dose and reduces normal tissue complications through organ at risk sparing. Given the potential advantages of IMRT and the availability of IMRT-enabled treatment planning systems and linear accelerators, IMRT has been introduced in a number of disease sites, including prostate cancer. This systematic review examined the evidence for IMRT in the treatment of prostate cancer in order to quantify the potential benefits of this new technology and to make recommendations for radiation treatment programmes considering adopting this technique. The findings were in favour of recommending IMRT over 3DCRT in the radical treatment of localised prostate cancer where doses greater than 70 Gy are required, based on a review of 11 published reports including 4559 patients. There were insufficient data to recommend IMRT over 3DCRT in the postoperative setting. Future research should examine image-guided IMRT in the post-prostatectomy setting, with altered fractionation, and in combination with hormone and chemotherapy.     

The Role of Hypofractionated Radiotherapy in Prostate Cancer

Purpose of Review

It is now accepted that prostate cancer has a low alpha/beta ratio, establishing a strong basis for hypofractionation of prostate radiotherapy. This review focuses on the rationale for hypofractionation and presents the evidence base for establishing moderate hypofractionation for localised disease as the new standard of care. The emerging evidence for extreme hypofractionation in managing localized and oligometastatic prostate cancer is reviewed.

Recent Findings

The 5-year efficacy and toxicity outcomes from four phase III studies have been published within the last 12 months. These studies randomizing over 6000 patients to conventional fractionation (1.8–2.0 Gy per fraction) or moderate hypofractionation (3.0–3.4 Gy per fraction). They demonstrate hypofractionation to be non-inferior to conventional fractionation.

Summary

Moderate hypofractionation for localized prostate cancer is safe and effective. There is a growing body of evidence in support of extreme hypofractionation for localized prostate cancer. Extreme hypofractionation may have a role in managing prostate oligometastases, but further studies are needed.

     

Intrafraction Prostate Motion Management for Ultra-Hypofractionated Radiotherapy of Prostate Cancer

Purpose: Determine the time-dependent magnitude of intrafraction prostate displacement and a cutoff for the tracking decision. Methods: Nine patients with localized prostate cancer were treated with ultra-hypofractionated radiotherapy (CyberKnife) with fiducial markers. Exact tract kV/kV imaging was used with an average interval of 19–92 s. A Gaussian distribution was calculated for the x-, y-, and z-directions (σ_x,y,z). The variation of prostate motion (μ_σ) was obtained by averaging the patients’ specifics, and the safety margin was calculated to be MAB = WYm + WBSs. Results: The calculated PTV safety margins were as follows: at 40 s: 0.55 mm (L/r), 0.85 mm (a/p), and 1.05 mm (s/i); at 60 s: 0.9 mm (L/r), 1.35 mm (a/p), and 1.55 mm (s/i); at 100 s: 1.5 mm (L/r), 2.3 mm (a/p), and 2.6 mm (s/i); at 150 s: 1.9 mm (L/r), 3.1 mm (a/p), and 3.6 mm (s/i); at 200 s: 2.2 mm (L/r), 3.8 mm (a/p), and 4.2 mm (s/i); and at 300 s: 2.6 mm (L/r), 5.3 mm (a/p), and 5.6 mm (s/i). A tracking cutoff of 2.5 min seemed reasonable. In order to achieve an accuracy of < 1 mm, tracking with < 50 s intervals was necessary. Conclusions: For ultra-hypofractionated radiotherapy of the prostate with treatment times > 2.5 min, intrafraction motion management is recommended.