Bryan H. Goldman

Updated Analysis of SWOG-Directed Intergroup Study 0116: A Phase III Trial of Adjuvant Radiochemotherapy Versus Observation After Curative Gastric Cancer Resection

PURPOSEnSurgical resection of gastric cancer has produced suboptimal survival despite multiple randomized trials that used postoperative chemotherapy or more aggressive surgical procedures. We performed a randomized phase III trial of postoperative radiochemotherapy in those at moderate risk of locoregional failure (LRF) following surgery. We originally reported results with 4-year median follow-up. This update, with a more than 10-year median follow-up, presents data on failure patterns and second malignancies and explores selected subset analyses.nnnPATIENTS AND METHODSnIn all, 559 patients with primaries ≥ T3 and/or node-positive gastric cancer were randomly assigned to observation versus radiochemotherapy after R0 resection. Fluorouracil and leucovorin were administered before, during, and after radiotherapy. Radiotherapy was given to all LRF sites to a dose of 45 Gy.nnnRESULTSnOverall survival (OS) and relapse-free survival (RFS) data demonstrate continued strong benefit from postoperative radiochemotherapy. The hazard ratio (HR) for OS is 1.32 (95% CI, 1.10 to 1.60; P = .0046). The HR for RFS is 1.51 (95% CI, 1.25 to 1.83; P < .001). Adjuvant radiochemotherapy produced substantial reduction in both overall relapse and locoregional relapse. Second malignancies were observed in 21 patients with radiotherapy versus eight with observation (P = .21). Subset analyses show robust treatment benefit in most subsets, with the exception of patients with diffuse histology who exhibited minimal nonsignificant treatment effect.nnnCONCLUSIONnIntergroup 0116 (INT-0116) demonstrates strong persistent benefit from adjuvant radiochemotherapy. Toxicities, including second malignancies, appear acceptable, given the magnitude of RFS and OS improvement. LRF reduction may account for the majority of overall relapse reduction. Adjuvant radiochemotherapy remains a rational standard therapy for curatively resected gastric cancer with primaries T3 or greater and/or positive nodes.

A phase 2 study of vorinostat for treatment of relapsed or refractory Hodgkin lymphoma: Southwest Oncology Group Study S0517

Abstract We performed a phase II study of oral vorinostat (200 mg twice daily, days 1–14 of a 21-day cycle), a histone and protein deacetylase inhibitor, to examine efficacy and tolerability in patients with relapsed/refractory Hodgkin lymphoma (HL) with ≤ 5 prior therapies. The primary endpoint was the objective response rate (ORR), with secondary endpoints of progression-free survival (PFS), overall survival (OS), safety and tolerability. A two-stage design was used for patient accrual. Twenty-five eligible patients were accrued in the first stage. Median time on treatment was 3.8 months. The ORR was 4% (one partial response). Median PFS was 4.8 months. The drug was well tolerated. The second stage of accrual was not opened due to few objective responses. Oral vorinostat has limited single-agent activity in relapsed/refractory HL. There was one partial response, while seven other patients had stable disease for > 1 year, including two with stable disease for nearly 3 years, suggesting that further studies in combination with other active agents in this setting may be warranted.

Fc gamma receptor 3a genotype predicts overall survival in follicular lymphoma patients treated on SWOG trials with combined monoclonal antibody plus chemotherapy but not chemotherapy alone.

Background Fc gamma receptor polymorphisms were linked to outcome in follicular lymphoma patients treated with single-agent rituximab, an anti-CD20 monoclonal antibody. In particular, 158F/F genotype of Fc gamma receptor 3A and 131R/R genotype of Fc gamma receptor 2A correlated with worse outcome compared to high-affinity 158V/V and 131H/H, respectively. We examined this association in the context of anti-CD20 monoclonal antibody combined with chemotherapy, as compared to chemotherapy alone, in follicular lymphoma patients treated on SWOG clinical trials. Design and Methods Tissue from 142 SWOG patients treated with chemotherapy alone (protocol S8809, n=70) or combined chemotherapy and anti-CD20 monoclonal antibody (rituximab and Iodine I-131 tositumomab on protocols S9800 and S9911, n=30 and 42, respectively) was analyzed. DNA was extracted and assayed for Fc gamma receptor 3A V158F and 2A R131H polymorphisms using a TaqMan SNP assay. Stratified Cox’s regression was used to assess association with overall survival. Results For Fc gamma receptor 3A, there was an association with overall survival in the combination therapy trials but not in the chemotherapy-only trial. Having at least one Fc gamma receptor 3A V allele was associated with improved overall survival versus F/F (HR=0.33, 95% CI, 0.11, 0.96, P=0.042). For overall survival, there was evidence of a statistical interaction between the use of mAb and the number of V alleles (0, 1, or 2) (P=0.006). There was no such association for Fc gamma receptor 2A. Conclusions Fc gamma receptor 3A polymorphism status may be predictive of survival in follicular lymphoma patients receiving treatments containing an anti-CD20 antibody but not treatment with chemotherapy alone. Thus, Fc gamma receptor 3A polymorphisms may be important to consider in designing new follicular lymphoma trials and new anti-CD20 monoclonal antibodies.

Clinical significance of MYC expression and/or “high grade” morphology in non-Burkitt, diffuse aggressive B-cell lymphomas: A SWOG S9704 correlative study

The clinicopathologic findings in Burkitt lymphoma (BL) and diffuse large B-cell lymphoma (DLBCL) may show significant overlap, and MYC abnormalities, found in all BLs, also occur in a subset of DLBCL. The 2008 World Health Organization classification introduced the category of “B-cell lymphoma, unclassifiable, with features intermediate between DLBCL and BL” (BCLU) in recognition of this overlap, but the clinical significance of BCLU (ie, “high-grade”) morphology and the relationship between BCLU morphology and MYC abnormalities remains unclear. In this study, we identified 260 cases of non-Burkitt, diffuse aggressive B-cell lymphomas from SWOG S9704, a phase 3 randomized study of standard immunochemotherapy versus autologous stem cell transplantation. Of these, 31 cases (12%) showed BCLU morphology, and 229 (88%) showed typical DLBCL morphology. Of 198, 27 (14%) were positive for MYC by immunohistochemistry. BCLU morphology was associated with an increased incidence of MYC expression but otherwise was not associated with distinct clinicopathologic features or significantly decreased survival. MYC-positive cases were morphologically and phenotypically heterogenous and were associated with poor progression-free and overall survival in multivariate analysis. These findings confirm that BCLU does not represent a distinct clinicopathologic entity and demonstrate that BCLU morphology alone does not significantly impact survival compared with typical DLBCL. In contrast, MYC protein expression is a poor prognostic factor that may be associated with either BCLU or DLBCL morphology, and MYC immunohistochemistry is suggested for routine prognostic evaluation (Clinicaltrials.gov identifier: NCT00004031).

Interim futility analysis with intermediate endpoints

Background Interim analysis of Phase III trials typically includes testing for both efficacy and futility. Futility testing is commonly performed on the primary outcome at very low levels (e.g., one-sided α=0.0025) at one or two times before final analysis. When overall survival is the primary outcome and events accrue slowly, and if a suitable intermediate endpoint is available, then using this endpoint for interim futility testing may yield a higher probability of stopping early for futility in the absence of any treatment effect. Purpose The purpose of this study is to explore the possibility of incorporating an intermediate endpoint into interim futility testing of Phase III trials. Methods Using a simple two-stage exponential survival model based on recent Southwest Oncology Group Phase III studies in several disease settings, we perform a series of simulation studies. Survival data are simulated under both the null and alternative hypotheses, and analyzed using overall survival, progression-free survival, and a composite endpoint for futility testing. Results In all disease settings examined here, when survival data were simulated under the null hypothesis, the probability of stopping a trial early for futility was substantially increased by incorporating PFS into interim futility analyses. When testing for futility with the composite endpoint, average patient accrual was reduced by 6—11% in a wide variety of disease settings. In the study scenario with the longest survival, the savings in study duration was more dramatic than in patient resources. When data were simulated under the alternative hypothesis, this procedure resulted in a negligible loss of power. Limitations The properties of this procedure outside of the context of cancer clinical trials and/or using a different intermediate endpoint are not examined. These results also do not address its performance in the context of less conservative stopping rules. Conclusions Interim futility monitoring of Phase III trials using a suitable intermediate endpoint may substantially increase the probability of stopping early for futility when there is no treatment effect. These simulation studies suggest that this would lead to meaningful reductions in study duration and patient resources in many disease settings, with no substantial loss of power for the primary test of efficacy. Future work is needed to explore in detail whether modifications to the stopping rules used in this procedure may yield greater savings without compromising power. Clinical Trials 2008; 5: 14—22. http://ctj.sagepub.com

Low Serum Vitamin D Levels Are Associated With Inferior Survival in Follicular Lymphoma: A Prospective Evaluation in SWOG and LYSA Studies

PURPOSEnRecent literature reports a potential association between high vitamin D and improved lymphoma prognosis. We evaluated the impact of pretreatment vitamin D on follicular lymphoma (FL) outcome.nnnPATIENTS AND METHODSnSWOG participants were previously untreated patients with FL enrolled onto SWOG clinical trials (S9800, S9911, or S0016) involving CHOP chemotherapy plus an anti-CD20 antibody (rituximab or iodine-131 tositumomab) between 1998 and 2008. Participants included in our second independent cohort were also previously untreated patients with FL enrolled onto the Lymphoma Study Association (LYSA) PRIMA trial of rituximab plus chemotherapy (randomly assigned to rituximab maintenance v observation) between 2004 and 2007. Using the gold-standard liquid chromatography-tandem mass spectrometry method, 25-hydroxyvitamin D was measured in stored baseline serum samples. The primary end point was progression-free survival (PFS).nnnRESULTSnAfter a median follow-up of 5.4 years, the adjusted PFS and overall survival hazard ratios for the SWOG cohort were 1.97 (95% CI, 1.10 to 3.53) and 4.16 (95% CI, 1.66 to 10.44), respectively, for those who were vitamin D deficient (< 20 ng/mL; 15% of cohort). After a median follow-up of 6.6 years, the adjusted PFS and overall survival hazard ratios for the LYSA cohort were 1.50 (95% CI, 0.93 to 2.42) and 1.92 (95% CI, 0.72 to 5.13), respectively, for those who were vitamin D deficient (< 10 ng/mL; 25% of cohort).nnnCONCLUSIONnAlthough statistical significance was not reached in the LYSA cohort, the consistent estimates of association between low vitamin D levels and FL outcomes in two independent cohorts suggests that serum vitamin D might be the first potentially modifiable factor to be associated with FL survival. Further investigation is needed to determine the effects of vitamin D supplementation in this clinical setting.

Modeling the Relationship between Progression-Free Survival and Overall Survival: The Phase II/III Trial

The standard phase II trial design has changed dramatically over the past decade. Randomized phase II studies have essentially become the standard phase II design in oncology for a variety of reasons. The use of these designs is motivated by concerns about the use of historical data to determine if a new agent or regimen shows promise of activity. However, randomized phase II designs come with the cost of increased study duration and patient resources. Progression-free survival (PFS) is an important endpoint used in many phase II designs. In many clinical settings, changes in PFS with the introduction of a new treatment may represent true benefit in terms of the gold standard outcome, overall survival (OS). The phase II/III design has been proposed as an approach to shorten the time of discovery of an active regimen. In this article, design considerations for a phase II/III trial are discussed and presented in terms of a model defining the relationship between OS and PFS. The design is also evaluated using 15 phase III trials completed in the Southwest Oncology Group (SWOG) between 1990 and 2005. The model provides a framework to evaluate the validity and properties of using a phase II/III design. In the evaluation of SWOG trials, three of four positive studies would have also proceeded to the final analysis and 10 of 11 negative studies would have stopped at the phase II analysis if a phase II/III design had been used. Through careful consideration and thorough evaluation of design properties, substantial gains could occur using this approach. Clin Cancer Res; 19(10); 2646–56. ©2013 AACR.

Genetic polymorphisms in oxidative stress-related genes are associated with outcomes following treatment for aggressive B-cell non-Hodgkin lymphoma

Variable survival outcomes are seen following treatment for aggressive non‐Hodgkin lymphoma (NHL). This study examined whether outcomes for aggressive B‐cell NHL are associated with single nucleotide polymorphisms (SNPs) in oxidative stress‐related genes, which can alter drug metabolism and immune responses. Genotypes for 53 SNPs in 29 genes were determined for 337 patients given anthracycline‐based therapies. Their associations with progression‐free survival (PFS) and overall survival (OS) were estimated by Cox proportional hazard regression; associations with hematologic toxicity were estimated by logistic regression. To validate the findings, the top three SNPs were tested in an independent cohort of 572 DLBCL patients. The top SNPs associated with PFS in the discovery cohort were the rare homozygotes for MPO rs2243828 (hazard ratio [HR]u2009=u20091.87, 95% confidence interval [CI]u2009=u20091.14–3.06, Pu2009=u20090.013), AKR1C3 rs10508293 (HRu2009=u20092.09, 95% CIu2009=u20091.28–3.41, Pu2009=u20090.0032) and NCF4 rs1883112 (HRu2009=u20090.66, 95% CIu2009=u20090.43–1.02, Pu2009=u20090.06). The association of the NCF4 SNP with PFS was replicated in the validation dataset (HRu2009=u20090.66, 95% CIu2009=u20090.44–1.01, Pu2009=u20090.05) and the meta‐analysis was significant (HRu2009=u20090.66, 95% CIu2009=u20090.49–0.89, Pu2009<u20090.01). The association of the MPO SNP was attenuated in the validation dataset, while the meta‐analysis remained significant (HRu2009=u20091.64, 95% CIu2009=u20091.12–2.41). These two SNPs showed similar trends with OS in the meta‐analysis (for NCF4, HRu2009=u20090.72, 95% CIu2009=u20090.51–1.02, Pu2009=u20090.07 and for MPO, HRu2009=u20092.06, 95% CIu2009=u20091.36–3.12, Pu2009<u20090.01). In addition, patients with the rare homozygote of the NCF4 SNP had an increased risk of hematologic toxicity. We concluded that genetic variations in NCF4 may contribute to treatment outcomes for patients with aggressive NHL. Am. J. Hematol. 89:639–645, 2014.

Modeling distortion product otoacoustic emission input/output functions using segmented regression

Distortion product otoacoustic emissions (DPOAEs) are low-level acoustic signals, the detection of which involves extraction from a background of noise. Boege and Janssen [J. Acoust. Soc. Am. 111, 1810-1818 (2002)] described a method for modeling the presence and growth of these responses. While improving growth function parameter estimation, this technique excludes a significant fraction of the data (especially low-level responses), and relies on ad hoc model fit acceptance criteria. The statistical difficulties associated with these limitations are described, and a weighted segmented linear regression model that avoids them is proposed. A simple test is presented for the presence of DPOAE growth. This technique is compared to that of Boege and Janssen in a dataset of 9 556 input/output (I/O) functions collected over 4 years on 866 ears from 379 construction apprentices and 63 age-matched controls. Comparisons are made on the entire dataset and within audiometric hearing loss categories. Segmented regression avoids the statistical pitfalls of the previous method, allows estimation of the threshold and slope of auditory response on a far greater number of I/O functions, and improves estimation of these parameters in this dataset. The potential for this method to yield more sensitive metrics of hearing function and compromise is discussed.