A Phase 3 Trial of 2 Years of Androgen Suppression and Radiation Therapy With or Without Adjuvant Chemotherapy for High-Risk Prostate Cancer: Final Results of Radiation Therapy Oncology Group Phase 3 Randomized Trial NRG Oncology RTOG 9902

PURPOSE

Long-term (LT) androgen suppression (AS) with radiation therapy (RT) is a standard treatment of high-risk, localized prostate cancer (PCa). Radiation Therapy Oncology Group 9902 was a randomized trial testing the hypothesis that adjuvant combination chemotherapy (CT) with paclitaxel, estramustine, and oral etoposide plus LT AS plus RT would improve overall survival (OS).

METHODS AND MATERIALS

Patients with high-risk PCa (prostate-specific antigen 20-100 ng/mL and Gleason score [GS] ≥ 7 or clinical stage ≥ T2 and GS ≥ 8) were randomized to RT and AS (AS + RT) alone or with adjuvant CT (AS + RT + CT). CT was given as four 21-day cycles, delivered beginning 28 days after 70.2 Gy of RT. AS was given as luteinizing hormone-releasing hormone for 24 months, beginning 2 months before RT plus an oral antiandrogen for 4 months before and during RT. The study was designed based on a 6% improvement in OS from 79% to 85% at 5 years, with 90% power and a 2-sided alpha of 0.05.

RESULTS

A total of 397 patients (380 eligible) were randomized. The patients had high-risk PCa, 68% with GS 8 to 10 and 34% T3 to T4 tumors, and median prostate-specific antigen of 22.6 ng/mL. The median follow-up period was 9.2 years. The trial closed early because of excess thromboembolic toxicity in the CT arm. The 10-year results for all randomized patients revealed no significant difference between the AS + RT and AS + RT + CT arms in OS (65% vs 63%; P=.81), biochemical failure (58% vs 54%; P=.82), local progression (11% vs 7%; P=.09), distant metastases (16% vs 14%; P=.42), or disease-free survival (22% vs 26%; P=.61).

CONCLUSIONS

NRG Oncology RTOG 9902 showed no significant differences in OS, biochemical failure, local progression, distant metastases, or disease-free survival with the addition of adjuvant CT to LT AS + RT. The trial results provide valuable data regarding the natural history of high-risk PCa treated with LT AS + RT and have implications for the feasibility of clinical trial accrual and tolerability using CT for PCa.

Importance of Local Control in Early-Stage Prostate Cancer: Outcomes of Patients With Positive Post-Radiation Therapy Biopsy Results Treated in RTOG 9408

PURPOSE

The purpose of this study was to assess the association between positive post-radiation therapy (RT) biopsy results and subsequent clinical outcomes in males with localized prostate cancer.

METHODS AND MATERIALS

Radiation Therapy Oncology Group study 94-08 analyzed 1979 males with prostate cancer, stage T1b-T2b and prostate-specific antigen concentrations of ≤ 20 ng/dL, to investigate whether 4 months of total androgen suppression (TAS) added to RT improved survival compared to RT alone. Patients randomized to receive TAS received flutamide with luteinizing hormone releasing hormone (LHRH) agonist. According to protocol, patients without evidence of clinical recurrence or initiation of additional endocrine therapy underwent repeat prostate biopsy 2 years after RT completion. Statistical analysis was performed to evaluate the impact of positive post-RT biopsy results on clinical outcomes.

RESULTS

A total of 831 patients underwent post-RT biopsy, 398 were treated with RT alone and 433 with RT plus TAS. Patients with positive post-RT biopsy results had higher rates of biochemical failure (hazard ratio [HR] = 1.7; 95% confidence interval [CI] = 1.3-2.1) and distant metastasis (HR = 2.4; 95% CI = 1.3-4.4) and inferior disease-specific survival (HR = 3.8; 95% CI = 1.9-7.5). Positive biopsy results remained predictive of such outcomes after correction for potential confounders such as Gleason score, tumor stage, and TAS administration. Prior TAS therapy did not prevent elevated risk of adverse outcome in the setting of post-RT positive biopsy results. Patients with Gleason score ≥ 7 with a positive biopsy result additionally had inferior overall survival compared to those with a negative biopsy result (HR = 1.56; 95% CI = 1.04-2.35).

CONCLUSIONS

Positive post-RT biopsy is associated with increased rates of distant metastases and inferior disease-specific survival in patients treated with definitive RT and was associated with inferior overall survival in patients with high-grade tumors.

Clinical experience using a video-guided spirometry system for deep inhalation breath-hold radiotherapy of left-sided breast cancer

The purpose was to report clinical experience of a video-guided spirometry system in applying deep inhalation breath-hold (DIBH) radiotherapy for left-sided breast cancer, and to study the systematic and random uncertainties, intra- and interfraction motion and impact on cardiac dose associated with DIBH. The data from 28 left-sided breast cancer patients treated with spirometer-guided DIBH radiation were studied. Dosimetric comparisons between free-breathing (FB) and DIBH plans were performed. The distance between the heart and chest wall measured on the digitally reconstructed radiographs (DRR) and MV portal images, dDRR(DIBH) and dport(DIBH), respectively, was compared as a measure of DIBH setup uncertainty. The difference (Δd) between dDRR(DIBH) and dport(DIBH) was defined as the systematic uncertainty. The standard deviation of Δd for each patient was defined as the random uncertainty. MV cine images during radiation were acquired. Affine registrations of the cine images acquired during one fraction and multiple fractions were performed to study the intra- and interfraction motion of the chest wall. The median chest wall motion was used as the metric for intra- and interfraction analysis. Breast motions in superior-inferior (SI) direction and "AP" (defined on the DRR or MV portal image as the direction perpendicular to the SI direction) are reported. Systematic and random uncertainties of 3.8 mm and 2mm, respectively, were found for this spirometer-guided DIBH treatment. MV cine analysis showed that intrafraction chest wall motions during DIBH were 0.3mm in "AP" and 0.6 mm in SI. The interfraction chest wall motions were 3.6 mm in "AP" and 3.4 mm in SI. Utilization of DIBH with this spirometry system led to a statistically significant reduction of cardiac dose relative to FB treatment. The DIBH using video-guided spirometry provided reproducible cardiac sparing with minimal intra- and interfraction chest wall motion, and thus is a valuable adjunct to modern breast treatment techniques.

Defining a standard set of patient-centered outcomes for men with localized prostate cancer

BACKGROUND

Value-based health care has been proposed as a unifying force to drive improved outcomes and cost containment.

OBJECTIVE

To develop a standard set of multidimensional patient-centered health outcomes for tracking, comparing, and improving localized prostate cancer (PCa) treatment value.

DESIGN, SETTING, AND PARTICIPANTS

We convened an international working group of patients, registry experts, urologists, and radiation oncologists to review existing data and practices.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The group defined a recommended standard set representing who should be tracked, what should be measured and at what time points, and what data are necessary to make meaningful comparisons. Using a modified Delphi method over a series of teleconferences, the group reached consensus for the Standard Set.

RESULTS AND LIMITATIONS

We recommend that the Standard Set apply to men with newly diagnosed localized PCa treated with active surveillance, surgery, radiation, or other methods. The Standard Set includes acute toxicities occurring within 6 mo of treatment as well as patient-reported outcomes tracked regularly out to 10 yr. Patient-reported domains of urinary incontinence and irritation, bowel symptoms, sexual symptoms, and hormonal symptoms are included, and the recommended measurement tool is the Expanded Prostate Cancer Index Composite Short Form. Disease control outcomes include overall, cause-specific, metastasis-free, and biochemical relapse-free survival. Baseline clinical, pathologic, and comorbidity information is included to improve the interpretability of comparisons.

CONCLUSIONS

We have defined a simple, easily implemented set of outcomes that we believe should be measured in all men with localized PCa as a crucial first step in improving the value of care.

PATIENT SUMMARY

Measuring, reporting, and comparing identical outcomes across treatments and treatment centers will provide patients and providers with information to make informed treatment decisions. We defined a set of outcomes that we recommend being tracked for every man being treated for localized prostate cancer.

A tissue biomarker-based model that identifies patients with a high risk of distant metastasis and differential survival by length of androgen deprivation therapy in RTOG protocol 92-02

PURPOSE

To examine the relationship between the expression of 7 promising apoptotic/cell proliferation proteins (Ki-67, p53, MDM2, bcl-2, bax, p16, and Cox-2) and risk of distant metastasis.

EXPERIMENTAL DESIGN

RTOG 92-02 compared external beam radiotherapy (EBRT) to approximately 70 Gy + short-term androgen deprivation therapy (STADT) with EBRT + long-term ADT (LTADT). Immunohistochemical analysis was available for ≥4 biomarkers in 616 of 1,521 assessable cases. Biomarkers were evaluated individually and jointly via multivariable modeling of distant metastasis using competing risks hazards regression, adjusting for age, prostate-specific antigen, Gleason score, T stage, and treatment.

RESULTS

Modeling identified four biomarkers (Ki-67, MDM2, p16 and Cox-2) that were jointly associated with distant metastasis. The c-index was 0.77 for the full model and 0.70 for the model without the biomarkers; a relative improvement of about 10% (likelihood ratio P < 0.001). Subdivision of the patients into quartiles based on predicted distant metastasis risk identified a high-risk group with 10-year distant metastasis risk of 52.5% after EBRT + STADT and 31% with EBRT + LTADT; associated 10-year prostate cancer-specific mortality (PCSM) risks were 45.9% and 14.5% with STADT and LTADT.

CONCLUSION

Four biomarkers were found to contribute significantly to a model that predicted distant metastasis and identified a subgroup of patients at a particularly high risk of both distant metastasis and PCSM when EBRT + STADT was used. LTADT resulted in significant reductions in distant metastasis and improvements in PCSM, and there was a suggestion of greater importance in the very high risk subgroup.

The critical role of the pathologist in determining eligibility for active surveillance as a management option in patients with prostate cancer: consensus statement with recommendations supported by the College of American Pathologists, International Society of Urological Pathology, Association of Directors of Anatomic and Surgical Pathology, the New Zealand Society of Pathologists, and the Prostate Cancer Foundation

CONTEXT

Prostate cancer remains a significant public health problem. Recent publications of randomized trials and the US Preventive Services Task Force recommendations have drawn attention to overtreatment of localized, low-risk prostate cancer. Active surveillance, in which patients undergo regular visits with serum prostate-specific antigen tests and repeat prostate biopsies, rather than aggressive treatment with curative intent, may address overtreatment of low-risk prostate cancer. It is apparent that a greater awareness of the critical role of pathologists in determining eligibility for active surveillance is needed.

OBJECTIVES

To review the state of current knowledge about the role of active surveillance in the management of prostate cancer and to provide a multidisciplinary report focusing on pathologic parameters important to the successful identification of patients likely to succeed with active surveillance, to determine the role of molecular tests in increasing the safety of active surveillance, and to provide future directions.

DESIGN

Systematic review of literature on active surveillance for low-risk prostate cancer, pathologic parameters important for appropriate stratification, and issues regarding interobserver reproducibility. Expert panels were created to delineate the fundamental questions confronting the clinical and pathologic aspects of management of men on active surveillance.

RESULTS

Expert panelists identified pathologic parameters important for management and the related diagnostic and reporting issues. Consensus recommendations were generated where appropriate.

CONCLUSIONS

Active surveillance is an important management option for men with low-risk prostate cancer. Vital to this process is the critical role pathologic parameters have in identifying appropriate candidates for active surveillance. These findings need to be reproducible and consistently reported by surgical pathologists with accurate pathology reporting.

Drug and device development for localized prostate cancer: report of a Food and Drug Administration/American Urological Association public workshop

Summary of the discussion at a public workshop cosponsored by the U.S. Food and Drug Administration (FDA) and the American Urological Association reviewing potential trial designs for product and device development for the treatment of localized prostate cancer. Product development for treatment of localized prostate cancer has been stymied by the impracticality of using overall survival as an endpoint in patients with localized disease and the lack of acceptable surrogate endpoints. A workshop evaluating potential trial designs for the development of therapies for localized prostate cancer was held in San Diego, CA, in May 2013. Invited experts represented multiple stakeholders, including urology, medical oncology, radiation oncology, industry, and patient advocates. The expert panel discussed development of products for all risk strata of clinically localized prostate cancer. The panel responded to specific questions from FDA, discussing trial design for patients with low-, intermediate-, and high-risk prostate cancer, focal therapy for prostate cancer, patients who have undergone definitive radiation therapy, and adjuvant therapy for patients undergoing radiation therapy or surgery. Expert commentary provided by the panel will inform a planned FDA guidance on pathways for product and device development for treatment of localized prostate cancer and will be discussed at meetings of the FDA's Oncologic Drugs Advisory Committee. FDA intends to develop a set of principles that can be used to promote the development of new products or devices for the treatment of this disease.

Adequacy of inhale/exhale breathhold CT based ITV margins and image-guided registration for free-breathing pancreas and liver SBRT

Purpose

To evaluate use of breath-hold CTs and implanted fiducials for definition of the internal target volume (ITV) margin for upper abdominal stereotactic body radiation therapy (SBRT). To study the statistics of inter- and intra-fractional motion information.

Methods and materials

11 patients treated with SBRT for locally advanced pancreatic cancer (LAPC) or liver cancer were included in the study. Patients underwent fiducial implantation, free-breathing CT and breath-hold CTs at end inhalation/exhalation. All patients were planned and treated with SBRT using volumetric modulated arc therapy (VMAT). Two margin strategies were studied: Strategy I uses PTV = ITV + 3 mm; Strategy II uses PTV = GTV + 1.5 cm. Both CBCT and kV orthogonal images were taken and analyzed for setup before patient treatments. Tumor motion statistics based on skeletal registration and on fiducial registration were analyzed by fitting to Gaussian functions.

Results

All 11 patients met SBRT planning dose constraints using strategy I. Average ITV margins for the 11 patients were 2 mm RL, 6 mm AP, and 6 mm SI. Skeletal registration resulted in high probability (RL = 69%, AP = 4.6%, SI = 39%) that part of the tumor will be outside the ITV. With the 3 mm ITV expansion (Strategy 1), the probability reduced to RL 32%, AP 0.3%, SI 20% for skeletal registration; and RL 1.2%, AP 0%, SI 7% for fiducial registration. All 7 pancreatic patients and 2 liver patients failed to meet SBRT dose constraints using strategy II. The liver dose was increased by 36% for the other 2 liver patients that met the SBRT dose constraints with strategy II.

Conclusions

Image guidance matching to skeletal anatomy is inadequate for SBRT positioning in the upper abdomen and usage of fiducials is highly recommended. Even with fiducial implantation and definition of an ITV, a minimal 3 mm planning margin around the ITV is needed to accommodate intra-fractional uncertainties.

Can electronic web-based technology improve quality of life data collection? Analysis of Radiation Therapy Oncology Group 0828

PURPOSE

Missing data are a significant problem in clinical trials, particularly for quality of life (QOL), which cannot be obtained retrospectively. The purpose of this study was to evaluate the feasibility of an electronic web-based strategy for QOL data collection in a cooperative group radiation oncology trial setting.

METHODS AND MATERIALS

Radiation Therapy Oncology Group (RTOG) 0828 was a prospective National Cancer Institute cooperative group companion study of RTOG-0415, a randomized study of conventional versus hypofractionated radiation. Forty-nine English-speaking patients with favorable risk prostate cancer who enrolled on RTOG-0415 consented to using web-based technology for completing QOL. In RTOG-0415, using paper forms, the 6-month QOL compliance rate was 52%. The purpose of RTOG-0828 was to test the feasibility of a web-based strategy with the goal of increasing the 6-month QOL completion rate by 25% (from 52% to 77%) for a relative improvement of ~50%. The web-based tool used in this study was VisionTree Optimal Care (VTOC; VisionTree Software, Inc, San Diego, CA), a Health-Insurance-Portability-Accountability-Act secure, online technology that allows real-time tracking and e-mail reminders. The primary endpoint was the 6-month compliance rate for the validated QOL instrument, Expanded Prostate Index Composite.

RESULTS

The QOL completion rate at baseline was 98%. Compared with the prior 52% QOL completion rate at 6 months using paper forms, the QOL web-based completion rate at 6 months was 90% (2-sided P value < .001). At 12 months, the EPIC completion rate was 82% (compared with 36% using paper forms).

CONCLUSIONS

This RTOG study suggests that a web-based strategy to collect QOL appears to be feasible in the cooperative group radiation oncology trial setting and is associated with an increase in the 6-month QOL compliance rate compared with the prior method of using paper forms. The RTOG plans to further test this strategy in a head-and-neck cancer trial across all participating RTOG sites.

Transurethral surgery and twice-daily radiation plus paclitaxel-cisplatin or fluorouracil-cisplatin with selective bladder preservation and adjuvant chemotherapy for patients with muscle invasive bladder cancer (RTOG 0233): a randomised multicentre phase 2 trial

BACKGROUND

We assessed effectiveness, safety, and tolerability of paclitaxel or fluorouracil when added to radiation plus cisplatin followed by adjuvant chemotherapy in a programme of selected bladder preservation for patients with muscle invasive bladder cancer.

METHODS

In our randomised phase 2 trial, we enrolled patients with T2-4a transitional cell carcinoma of the bladder at 24 medical centres in the USA. We randomly allocated patients to receive paclitaxel plus cisplatin (paclitaxel group) or fluorouracil plus cisplatin (fluorouracil group) with twice-daily radiation in random block sizes per site on the basis of clinical T-stage (T2 vs T3-4). Patients and physicians were aware of treatment assignment. All patients had transurethral resection of bladder tumour and twice-daily radiotherapy to 40·3 Gy, along with allocated chemotherapy, followed by cystoscopic and biopsy assessment of response. Patients who had a tumour response with downstaging to T0, Tcis, or Ta received consolidation chemoradiotherapy to 64·3 Gy, with the same chemotherapy regimen as in the induction phase. Patients received adjuvant cisplatin-gemcitabine-paclitaxel after the end of chemoradiotherapy. If, after induction, persistent disease was graded as T1 or worse, we recommended patients undergo cystectomy and adjuvant chemotherapy. We assessed the primary endpoints of rates of treatment completion and toxic effects in all randomly allocated patients. This study is registered with ClinicalTrials.gov, number NCT00055601.

FINDINGS

Between Dec 13, 2002, and Jan 11, 2008, we enrolled 97 patients, of whom 93 were eligible for analysis. Median follow-up was 5·0 years (IQR 5·0-6·2). Of 46 patients in the paclitaxel group, 45 (98%) completed induction (16 [35%] with grade 3-4 toxicity), 39 (85%) completed induction and consolidation (11 [24%] with grade 3-4 toxicity due to consolidation), and 31 (67%) completed the entire protocol with adjuvant chemotherapy. 34 (85%) of 40 assessable patients in the paclitaxel group had grade 3-4 toxicity during adjuvant chemotherapy. Of 47 patients in the fluorouracil group, 45 (96%) completed induction (nine [19%] with grade 3-4 toxicity), 39 (83%) completed induction and consolidation (12 [26%] had grade 3-4 toxicity due to consolidation), and 25 (53%) completed the entire protocol with adjuvant chemotherapy. 31 (76%) of 41 assessable patients in the fluorouracil group had grade 3-4 toxicity during adjuvant chemotherapy. Five (11%) patients treated with the paclitaxel regimen and three (6%) patients treated with the fluorouracil regimen developed late grade 3-4 radiotherapy toxicities. 11 (24%) patients treated with the paclitaxel regimen and 16 (34%) patients treated with the fluorouracil regimen developed late grade 3-4 toxicities unrelated to radiotherapy. One patient (in the fluorouracil group) died during follow-up. Six (13%) patients in the paclitaxel group and in three (6%) patients in the fluorouracil group discontinued due to treatment-related toxicity.

INTERPRETATION

In the absence of phase 3 data, our findings could inform selection of a bladder-sparing trimodality chemotherapy regimen for patients with muscle invasive bladder cancer.

FUNDING

US National Cancer Institute.