Sexual Health and Quality of Life in Patients With Low-Risk Early-Stage Cervical Cancer: Results From GCIG/CCTG CX.5/SHAPE Trial Comparing Simple Versus Radical Hysterectomy.

PURPOSE: Simple hysterectomy and pelvic node assessment (SHAPE) is a phase III randomized trial (ClinicalTrials.gov identifier: NCT01658930) reporting noninferiority of simple compared with radical hysterectomy for oncologic outcomes in low-risk cervical cancer. This study presents secondary outcomes of sexual health and quality of life (QOL) of the SHAPE trial. METHODS: Participants were randomly assigned to receive either radical or simple hysterectomy. Sexual health was assessed up to 36 months postoperatively using the Female Sexual Function Index (FSFI) and Female Sexual Distress Scale-Revised and QOL using European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 and Cervical Cancer-Specific Module (QLQ-CX24) questionnaires. RESULTS: Among participants with at least one QOL measure, clinical and pathologic characteristics were balanced and with no differences in preoperative baseline scores for sexual health or QOL between groups. FSFI total score met the cutoff for dysfunction up to 6 months (P = .02) in the radical hysterectomy group. Group differences favored simple hysterectomy for FSFI subscales: desire and arousal at 3 months (P ≤ .001) and pain and lubrication up to 12 months (P ≤ .018). Both groups met the cutoff for sexual distress but was higher in radical hysterectomy at 3 months (P = .018). For QLQ-CX24, symptom experience was significantly better up to 24 months (P = .031) and body image better at 3, 24, and 36 months (P ≤ .01) for simple hysterectomy. Sexual-vaginal functioning was significantly better up to 24 months (P ≤ .022) and more sexual activity up to 36 months (P = .024) in the simple hysterectomy arm. Global health status was significantly higher at 36 months for simple hysterectomy (P = .025). CONCLUSION: Simple hysterectomy was associated with lower rates of sexual dysfunction than radical hysterectomy, with a lower proportion of women having sustained sexual-vaginal dysfunction. These results further support the benefit of surgical de-escalation for low-risk cervical cancer.

Cost-effectiveness analysis of simple hysterectomy compared to radical hysterectomy for early cervical cancer: analysis from the GCIG/CCTG CX.5/SHAPE trial.

OBJECTIVE: SHAPE (Simple Hysterectomy And PElvic node assessment) was an international phase III trial demonstrating that simple hysterectomy was non-inferior to radical hysterectomy for pelvic recurrence risk, but superior for quality of life and sexual health. The objective was to conduct a cost-effectiveness analysis comparing simple vs. radical hysterectomy for low-risk early-stage cervical cancer. METHODS: Markov model compared the costs and benefits of simple vs. radical hysterectomy for early cervical cancer over a 5-year time horizon. Quality-adjusted life years (QALYs) were estimated from health utilities derived from EQ-5D-3L surveys. Sensitivity analyses accounted for uncertainty around key parameters. Monte Carlo simulation estimated complication numbers according to surgical procedure. RESULTS: Simple hysterectomy was more effective and less costly than radical hysterectomy. Average overall costs were $11,022 and $12,533, and average gains were 3.56 and 3.54 QALYs for simple and radical hysterectomy, respectively. Baseline health utility scores were 0.81 and 0.83 for simple and radical hysterectomy, respectively. By year 3, these scores improved for simple hysterectomy (0.82) but not for radical hysterectomy (0.82). Assuming 800 early cervical cancer patients annually in Canada, the model estimated 3 vs. 82 patients with urinary retention, and 49 vs. 86 patients with urinary incontinence persisting 4 weeks after simple vs. radical hysterectomy, respectively. Results were most sensitive to variability in health utilities after surgery, but stable through wide ranges of costs and recurrence estimates. CONCLUSION: Simple hysterectomy is less costly and more effective in terms of quality-adjusted life expectancy compared to radical hysterectomy for early cervical cancer. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01658930.

A randomized trial of ibrutinib and R-GDP prior to stem cell transplant in relapsed diffuse large B-cell lymphoma.

In the LY.17 randomized phase II clinical trial, adults with relapsed and refractory diffuse large B-cell lymphoma treated with ibrutinib-R-GDP (IR-GDP) for up to three cycles had more documented bacterial and fungal infections, without improvement in overall response, compared with R-GDP. CR, complete response; DLBCL, diffuse large B-cell lymphoma; PD, progressive disease; PR, partial response; R/R, relapsed/refractory; SD, stable disease.

Development and testing of a lymphoma clinical trial-specific frailty index: a secondary analysis of the NCIC-CTG LY.12 clinical trial.

The prevalence of frailty in clinical trials of lymphoma is unknown. We conducted a secondary analysis of the phase III LY.12 trial in which patients with relapsed aggressive non-Hodgkin lymphoma were randomized to different salvage regimens before autologous stem cell transplant. The primary objective was to construct a lymphoma clinical trials-specific frailty index (LyFI) using previously described methods. The secondary objective was to describe the association of frailty withover all and event-free survival (OS, EFS). The LyFI was constructed using 619 patients, and11% (N = 70) were classified as frail. Frailty was associated with EFS (HR 1.94, 95%CI 1.53-2.46) and OS (HR 2.01, 95%CI 1.57-2.58) in univariable analysis, but was only significant as a continuous (not binary) variable in multivariable analysis controlling for prognostic score, suggesting limitations of a FI in this trial population. Future work could validate the FI using clinical assessments and/or apply it to an older trial population.

Adjunctive Statistical Standardization of Adjuvant Estrogen Receptor and Progesterone Receptor in Canadian Cancer Trials Group MA.27 Postmenopausal Breast Cancer Trial of Exemestane Versus Anastrozole.

PURPOSE: ASCO/College of American Pathologists guidelines recommend reporting estrogen receptor (ER) and progesterone receptor (PgR) as positive with (1%-100%) staining. Statistically standardized quantitated positivity could indicate differential associations of positivity with breast cancer outcomes. METHODS: MA.27 (ClinicalTrials.gov identifier: NCT00066573) was a phase III adjuvant trial of exemestane versus anastrozole in postmenopausal women with early-stage breast cancer. Immunochemistry ER and PgR HSCORE and % positivity (%+) were centrally assessed by machine image quantitation and statistically standardized to mean 0 and standard deviation (SD) 1 after Box-Cox variance stabilization transformations of square for ER; for PgR, (1) natural logarithm (0.1 added to 0 HSCOREs and 0%+) and (2) square root. Our primary end point was MA.27 distant disease-free survival (DDFS) at a median 4.1-year follow-up, and secondary end point was event-free survival (EFS). Univariate survival with cut points at SDs about a mean of 0 (≤-1; (-1, 0]; (0, 1]; >1) was described with Kaplan-Meier plots and examined with Wilcoxon (Peto-Prentice) test statistic. Adjusted Cox multivariable regressions had two-sided Wald tests and nominal significance P < .05. RESULTS: Of 7,576 women accrued, 3,048 women's tumors had machine-quantitated image analysis results: 2,900 (95%) for ER, 2,726 (89%) for PgR, and 2,582 (85% of 3,048) with both ER and PgR. Higher statistically standardized ER and PgR HSCORE and %+ were associated with better univariate DDFS and EFS (P < .001). In multivariable assessments, ER HSCORE and %+ were not significantly associated (P = .52-.88) with DDFS in models with PgR, whereas higher PgR HSCORE and %+ were significantly associated with better DDFS (P = .001) in models with ER. CONCLUSION: Adjunctive statistical standardization differentiated quantitated levels of ER and PgR. Patients with higher ER- and PgR-standardized units had superior DDFS compared with those with HSCOREs and %+ ≤-1.

Canadian cancer trials group LY.17: A randomized phase II study evaluating novel salvage therapy pre-autologous stem cell transplant in relapsed/refractory diffuse large B-cell lymphoma-outcome of rituximab-dose-intensive cyclophosphamide, etoposide, cisplatin (R-DICEP) versus R-GDP.

The Canadian Cancer Trials Group (CCTG) LY.17 is an ongoing multi-arm randomized phase II trial evaluating novel salvage therapies compared with R-GDP (rituximab, gemcitabine, dexamethasone and cisplatin) in autologous stem cell transplantation (ASCT)-eligible patients with relapsed/refractory diffuse large B-cell lymphoma (RR-DLBCL). This component of the LY.17 trial evaluated a dose-intensive chemotherapy approach using a single cycle of inpatient R-DICEP (rituximab, dose-intensive cyclophosphamide, etoposide and cisplatin) to achieve both lymphoma response and stem cell mobilization, shortening time to ASCT. This report is the result of the protocol-specified second interim analysis of the 67 patients who were randomized to either 1 cycle of R-DICEP or to 3 cycles of R-GDP. The overall response rate (ORR) was 65.6% for R-DICEP and 48.6% for R-GDP. The ASCT rate was 71.9% versus 54.3%, and 1-year progression-free survival rate was 42% versus 32%, respectively, for R-DICEP versus R-GDP. Although the improvement in ORR for R-DICEP versus R-GDP exceeded the pre-specified 10% threshold to proceed to full accrual of 64 patients/arm, higher rates of grade 3-5 toxicities, and the need for hospitalization led to the decision to stop this arm of the study. CCTG LY.17 will continue to evaluate different salvage regimens that incorporate novel agents.

Simple versus Radical Hysterectomy in Women with Low-Risk Cervical Cancer.

BACKGROUND: Retrospective data suggest that the incidence of parametrial infiltration is low in patients with early-stage low-risk cervical cancer, which raises questions regarding the need for radical hysterectomy in these patients. However, data from large, randomized trials comparing outcomes of radical and simple hysterectomy are lacking. METHODS: We conducted a multicenter, randomized, noninferiority trial comparing radical hysterectomy with simple hysterectomy including lymph-node assessment in patients with low-risk cervical cancer (lesions of ≤2 cm with limited stromal invasion). The primary outcome was cancer recurrence in the pelvic area (pelvic recurrence) at 3 years. The prespecified noninferiority margin for the between-group difference in pelvic recurrence at 3 years was 4 percentage points. RESULTS: Among 700 patients who underwent randomization (350 in each group), the majority had tumors that were stage IB1 according to the 2009 International Federation of Gynecology and Obstetrics (FIGO) criteria (91.7%), that had squamous-cell histologic features (61.7%), and that were grade 1 or 2 (59.3%). With a median follow-up time of 4.5 years, the incidence of pelvic recurrence at 3 years was 2.17% in the radical hysterectomy group and 2.52% in the simple hysterectomy group (an absolute difference of 0.35 percentage points; 90% confidence interval, -1.62 to 2.32). Results were similar in a per-protocol analysis. The incidence of urinary incontinence was lower in the simple hysterectomy group than in the radical hysterectomy group within 4 weeks after surgery (2.4% vs. 5.5%; P = 0.048) and beyond 4 weeks (4.7% vs. 11.0%; P = 0.003). The incidence of urinary retention in the simple hysterectomy group was also lower than that in the radical hysterectomy group within 4 weeks after surgery (0.6% vs. 11.0%; P<0.001) and beyond 4 weeks (0.6% vs. 9.9%; P<0.001). CONCLUSIONS: In patients with low-risk cervical cancer, simple hysterectomy was not inferior to radical hysterectomy with respect to the 3-year incidence of pelvic recurrence and was associated with a lower risk of urinary incontinence or retention. (Funded by the Canadian Cancer Society and others; ClinicalTrials.gov number, NCT01658930.).

Evaluating the Utility and Privacy of Synthetic Breast Cancer Clinical Trial Data Sets.

PURPOSE: There is strong interest from patients, researchers, the pharmaceutical industry, medical journal editors, funders of research, and regulators in sharing clinical trial data for secondary analysis. However, data access remains a challenge because of concerns about patient privacy. It has been argued that synthetic data generation (SDG) is an effective way to address these privacy concerns. There is a dearth of evidence supporting this on oncology clinical trial data sets, and on the utility of privacy-preserving synthetic data. The objective of the proposed study is to validate the utility and privacy risks of synthetic clinical trial data sets across multiple SDG techniques. METHODS: We synthesized data sets from eight breast cancer clinical trial data sets using three types of generative models: sequential synthesis, conditional generative adversarial network, and variational autoencoder. Synthetic data utility was evaluated by replicating the published analyses on the synthetic data and assessing concordance of effect estimates and CIs between real and synthetic data. Privacy was evaluated by measuring attribution disclosure risk and membership disclosure risk. RESULTS: Utility was highest using the sequential synthesis method where all results were replicable and the CI overlap most similar or higher for seven of eight data sets. Both types of privacy risks were low across all three types of generative models. DISCUSSION: Synthetic data using sequential synthesis methods can act as a proxy for real clinical trial data sets, and simultaneously have low privacy risks. This type of generative model can be one way to enable broader sharing of clinical trial data.

Effect of Metformin Versus Placebo on New Primary Cancers in Canadian Cancer Trials Group MA.32: A Secondary Analysis of a Phase III Randomized Double-Blind Trial in Early Breast Cancer.

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned coprimary or secondary analyses are not yet available. Clinical trial updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.Metformin has been associated with lower cancer risk in epidemiologic and preclinical research. In the MA.32 randomized adjuvant breast cancer trial, metformin (v placebo) did not affect invasive disease-free or overall survival. Here, we report metformin effects on the risk of new cancer. Between 2010 and 2013, 3,649 patients with breast cancer younger than 75 years without diabetes with high-risk T1-3, N0-3 M0 breast cancer (any estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2) were randomly assigned to metformin 850 mg orally twice a day or placebo twice a day for 5 years. New primary invasive cancers (outside the ipsilateral breast) developing as a first event were identified. Time to events was described by the competing risks method; two-sided likelihood ratio tests adjusting for age, BMI, smoking, and alcohol intake were used to compare metformin versus placebo arms. A total of 184 patients developed new invasive cancers: 102 metformin and 82 placebo, hazard ratio (HR), 1.25; 95% CI, 0.94 to 1.68; P = .13. These included 48 contralateral invasive breast cancers (27 metformin v 21 placebo), HR, 1.29; 95% CI, 0.72 to 2.27; P = .40 and 136 new nonbreast primary cancers (75 metformin v 61 placebo), HR, 1.24; 95% CI, 0.88 to 1.74; P = .21. Metformin did not reduce the risk of new cancer development in these nondiabetic patients with breast cancer.

The New NCI Precision Medicine Trials.

Basket, umbrella, and platform trial designs (master protocols) have emerged over the last decade to study precision medicine approaches in oncology. First-generation trials like NCI-MATCH (Molecular Analysis for Therapy Choice) have proven the principle that studying targeted therapies on a large scale is feasible both from the laboratory and clinical perspectives. However, single-agent targeted therapies have shown limited ability to control metastatic disease, despite careful matching of drug to target. As such, newer approaches employing combinations of targeted therapy, or targeted therapy with standard therapies, need to be considered. The NCI has recently embarked on three second-generation precision medicine trials to address this need: ComboMATCH, iMATCH, and myeloMATCH. The design of these trials and necessary infrastructure are discussed in the following perspective.

Impact of BMI in Patients With Early Hormone Receptor-Positive Breast Cancer Receiving Endocrine Therapy With or Without Palbociclib in the PALLAS Trial.

PURPOSE: BMI affects breast cancer risk and prognosis. In contrast to cytotoxic chemotherapy, CDK4/6 inhibitors are given at a fixed dose, irrespective of BMI or weight. This preplanned analysis of the global randomized PALLAS trial investigates the impact of BMI on the side-effect profile, treatment adherence, and efficacy of palbociclib. METHODS: Patients were categorized at baseline according to WHO BMI categories. Neutropenia rates were assessed with univariable and multivariable logistic regression. Time to early discontinuation of palbociclib was analyzed with Fine and Gray competing risk models. Unstratified Cox models were used to investigate the association between BMI category and time to invasive disease-free survival (iDFS). 95% CIs were derived. RESULTS: Of 5,698 patients included in this analysis, 68 (1.2%) were underweight, 2,082 (36.5%) normal weight, 1,818 (31.9%) overweight, and 1,730 (30.4%) obese at baseline. In the palbociclib arm, higher BMI was associated with a significant decrease in neutropenia (unadjusted odds ratio for 1-unit change, 0.93; 95% CI, 0.91 to 0.94; adjusted for age, race ethnicity, region, chemotherapy use, and Eastern Cooperative Oncology Group at baseline, 0.93; 95% CI, 0.92 to 0.95). This translated into a significant decrease in treatment discontinuation rate with higher BMI (adjusted hazard ratio [HR] for 10-unit change, 0.75; 95% CI, 0.67 to 0.83). There was no significant improvement in iDFS with the addition of palbociclib to ET in any weight category (normal weight HR, 0.84; 95% CI, 0.63 to 1.12; overweight HR, 1.10; 95% CI, 0.82 to 1.49; and obese HR, 0.95; 95% CI, 0.69 to 1.30) in this analysis early in follow-up (31 months). CONCLUSION: This preplanned analysis of the PALLAS trial demonstrates a significant impact of BMI on side effects, dose reductions, early treatment discontinuation, and relative dose intensity. Additional long-term follow-up will further evaluate whether BMI ultimately affects outcome.

Relapse Timing Is Associated With Distinct Evolutionary Dynamics in Diffuse Large B-Cell Lymphoma.

PURPOSE: Diffuse large B-cell lymphoma (DLBCL) is cured in more than 60% of patients, but outcomes remain poor for patients experiencing disease progression or relapse (refractory or relapsed DLBCL [rrDLBCL]), particularly if these events occur early. Although previous studies examining cohorts of rrDLBCL have identified features that are enriched at relapse, few have directly compared serial biopsies to uncover biological and evolutionary dynamics driving rrDLBCL. Here, we sought to confirm the relationship between relapse timing and outcomes after second-line (immuno)chemotherapy and determine the evolutionary dynamics that underpin that relationship. PATIENTS AND METHODS: Outcomes were examined in a population-based cohort of 221 patients with DLBCL who experienced progression/relapse after frontline treatment and were treated with second-line (immuno)chemotherapy with an intention-to-treat with autologous stem-cell transplantation (ASCT). Serial DLBCL biopsies from a partially overlapping cohort of 129 patients underwent molecular characterization, including whole-genome or whole-exome sequencing in 73 patients. RESULTS: Outcomes to second-line therapy and ASCT are superior for late relapse (>2 years postdiagnosis) versus primary refractory (<9 months) or early relapse (9-24 months). Diagnostic and relapse biopsies were mostly concordant for cell-of-origin classification and genetics-based subgroup. Despite this concordance, the number of mutations exclusive to each biopsy increased with time since diagnosis, and late relapses shared few mutations with their diagnostic counterpart, demonstrating a branching evolution pattern. In patients with highly divergent tumors, many of the same genes acquired new mutations independently in each tumor, suggesting that the earliest mutations in a shared precursor cell constrain tumor evolution toward the same genetics-based subgroups at both diagnosis and relapse. CONCLUSION: These results suggest that late relapses commonly represent genetically distinct and chemotherapy-naïve disease and have implications for optimal patient management.

Contact Days Associated With Cancer Treatments in the CCTG LY.12 Trial.

BACKGROUND: When cancer treatments have similar oncologic outcomes, the number of days with in-person healthcare contact (""contact days'') can help contextualize expected time use with each treatment. We assessed contact days in a completed randomized clinical trial. PATIENTS AND METHODS: We conducted a secondary analysis of the CCTG LY.12 RCT that evaluated 2-3 cycles of gemcitabine, dexamethasone, and cisplatin (GDP) vs. dexamethasone, cytarabine, and cisplatin (DHAP) in 619 patients with relapsed/refractory lymphoma prior to stem cell transplant. Primary analyses reported similar response rates and survival. We calculated patient-level "contact days" by analyzing trial forms. The study period was from assignment to progression or transplant. Days without healthcare contact were considered "home days''. We compared measures of contact days across arms. RESULTS: The study period was longer in the GDP arm (median 50, vs. 47 days, P = .007). Contact days were comparable in both arms (median 18 vs 19, P = 0.79), but home days were higher in the GDP arm (median 33 vs 28, P < .001). The proportion of contact days was lower in the GDP arm (34%, vs. 38%, P = .009). The GDP arm experienced more contact days related to planned outpatient chemotherapy (median, 10 vs. 8 days), but the DHAP arm experienced many more inpatient contact days (median, 11 vs. 0 days). CONCLUSIONS: Measures of time use, such as contact days, can be extracted from RCTs. In LY.12, despite comparable oncologic outcomes, GDP was associated with fewer contact days. Such information can guide decision-making for patients with hematological cancers, who already face significant healthcare contact.

Health-related quality of life in early-stage Hodgkin lymphoma: a longitudinal analysis of the ABVD arm in the randomized controlled trial HD.6.

Early-stage Hodgkin lymphoma has become one of the most curable hematologic malignancies. Depending upon the disease location, possible toxicities, and patient preference, chemotherapy alone with ABVD remains an accepted treatment modality for this disease. There remains a paucity of data regarding the longitudinal trajectory of health-related quality of life (HRQoL) in patients treated for HL. The impact of disease and treatment on HRQoL is increasingly important to understand as the number of long-term survivors increases. We report the longitudinal HRQoL using data prospectively collected from diagnosis up to 10 years post-treatment in the ABVD arm of the HD.6 randomized controlled trial for early-stage HL patients (N=169). We analyzed HRQoL using the EORTC QLQ-C30 collected at baseline, 3 months, 6 months, and 12 months after completion of chemotherapy and yearly up to year 10. Clinically and statistically significant improvements were noted for specific domains including emotional (3 months post-treatment), social (12 months post-treatment) and financial functioning (2 years post-treatment), and the specific symptom of fatigue (6 months post-treatment) during the follow-up period. To our knowledge, this is the first prospective, longitudinal analysis of HRQoL specifically among patients with early-stage HL treated with ABVD therapy alone. Although improvements were noted, sustained clinically and statistically significant improvements were noted only in select symptoms emphasizing the need to better understand and optimize HRQoL among this patient group.

Relapse timing is associated with distinct evolutionary dynamics in DLBCL.

Diffuse large B-cell lymphoma (DLBCL) is cured in over 60% of patients, but outcomes are poor for patients with relapsed or refractory disease (rrDLBCL). Here, we performed whole genome/exome sequencing (WGS/WES) on tumors from 73 serially-biopsied patients with rrDLBCL. Based on the observation that outcomes to salvage therapy/autologous stem cell transplantation are related to time-to-relapse, we stratified patients into groups according to relapse timing to explore the relationship to genetic divergence and sensitivity to salvage immunochemotherapy. The degree of mutational divergence increased with time between biopsies, yet tumor pairs were mostly concordant for cell-of-origin, oncogene rearrangement status and genetics-based subgroup. In patients with highly divergent tumors, several genes acquired exclusive mutations independently in each tumor, which, along with concordance of genetics-based subgroups, suggests that the earliest mutations in a shared precursor cell constrain tumor evolution. These results suggest that late relapses commonly represent genetically distinct and chemotherapy-naïve disease.

Effect of Metformin vs Placebo on Invasive Disease-Free Survival in Patients With Breast Cancer: The MA.32 Randomized Clinical Trial.

Importance: Metformin, a biguanide commonly used to treat type 2 diabetes, has been associated with potential beneficial effects across breast cancer subtypes in observational and preclinical studies. Objective: To determine whether the administration of adjuvant metformin (vs placebo) to patients with breast cancer without diabetes improves outcomes. Design, Setting, and Participants: MA.32, a phase 3 randomized, placebo-controlled, double-blind trial, conducted in Canada, Switzerland, US, and UK, enrolled 3649 patients with high-risk nonmetastatic breast cancer receiving standard therapy between August 2010 and March 2013, with follow-up to October 2020. Interventions: Patients were randomized (stratified for hormone receptor [estrogen receptor and/or progesterone receptor {ER/PgR}] status, positive vs negative; body mass index, ≤30 vs >30; human epidermal growth factor receptor 2 [ERBB2, formerly HER2 or HER2/neu], positive vs negative; and any vs no chemotherapy) to 850 mg of oral metformin twice a day (n = 1824) or oral placebo twice a day (n = 1825) for 5 years. Main Outcomes and Measures: The primary outcome was invasive disease-free survival in hormone receptor-positive breast cancer. Of the 8 secondary outcomes, overall survival, distant relapse-free survival, and breast cancer-free interval were analyzed. Results: Of the 3649 randomized patients (mean age, 52.4 years; 3643 women [99.8%]), all (100%) were included in analyses. After a second interim analysis, futility was declared for patients who were ER/PgR-, so the primary analysis was conducted for 2533 patients who were ER/PgR+. The median duration of follow-up in the ER/PgR+ group was 96.2 months (range, 0.2-121 months). Invasive disease-free survival events occurred in 465 patients who were ER/PgR+. The incidence rates for invasive disease-free survival events were 2.78 per 100 patient-years in the metformin group vs 2.74 per 100 patient-years in the placebo group (hazard ratio [HR], 1.01; 95% CI, 0.84-1.21; P = .93), and the incidence rates for death were 1.46 per 100 patient-years in the metformin group vs 1.32 per 100 patient-years in the placebo group (HR, 1.10; 95% CI, 0.86-1.41; P = .47). Among patients who were ER/PgR-, followed up for a median of 94.1 months, incidence of invasive disease-free survival events was 3.58 vs 3.60 per 100 patient-years, respectively (HR, 1.01; 95% CI, 0.79-1.30; P = .92). None of the 3 secondary outcomes analyzed in the ER/PgR+ group had statistically significant differences. Grade 3 nonhematological toxic events occurred more frequently in patients taking metformin than in patients taking placebo (21.5% vs 17.5%, respectively, P = .003). The most common grade 3 or higher adverse events in the metformin vs placebo groups were hypertension (2.4% vs 1.9%), irregular menses (1.5% vs 1.4%), and diarrhea (1.9% vs 7.0%). Conclusions and Relevance: Among patients with high-risk operable breast cancer without diabetes, the addition of metformin vs placebo to standard breast cancer treatment did not significantly improve invasive disease-free survival. Trial Registration: ClinicalTrials.gov Identifier: NCT01101438.

Treatment Exposure and Discontinuation in the PALbociclib CoLlaborative Adjuvant Study of Palbociclib With Adjuvant Endocrine Therapy for Hormone Receptor-Positive/Human Epidermal Growth Factor Receptor 2-Negative Early Breast Cancer (PALLAS/AFT-05/ABCSG-42/BIG-14-03).

PURPOSE: The PALLAS study investigated whether the addition of palbociclib, an oral CDK4/6 inhibitor, to adjuvant endocrine therapy (ET) improves invasive disease-free survival (iDFS) in early hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) breast cancer. In this analysis, we evaluated palbociclib exposure and discontinuation in PALLAS. METHODS: Patients with stage II-III HR+, HER2- disease were randomly assigned to 2 years of palbociclib with adjuvant ET versus ET alone. The primary objective was to compare iDFS between arms. Continuous monitoring of toxicity, dose modifications, and early discontinuation was performed. Association of baseline covariates with time to palbociclib reduction and discontinuation was analyzed with multivariable competing risk models. Landmark and inverse probability weighted per-protocol analyses were performed to assess the impact of drug persistence and exposure on iDFS. RESULTS: Of the 5,743 patient analysis population (2,840 initiating palbociclib), 1,199 (42.2%) stopped palbociclib before 2 years, the majority (772, 27.2%) for adverse effects, most commonly neutropenia and fatigue. Discontinuation of ET did not differ between arms. Discontinuations for non-protocol-defined reasons were greater in the first 3 months of palbociclib, and in the first calendar year of accrual, and declined over time. No significant relationship was seen between longer palbociclib duration or ≥ 70% exposure intensity and improved iDFS. In the weighted per-protocol analysis, no improvement in iDFS was observed in patients receiving palbociclib versus not (hazard ratio 0.89; 95% CI, 0.72 to 1.11). CONCLUSION: Despite observed rates of discontinuation in PALLAS, analyses suggest that the lack of significant iDFS difference between arms was not directly related to inadequate palbociclib exposure. However, the discontinuation rate illustrates the challenge of introducing novel adjuvant treatments, and the need for interventions to improve persistence with oral cancer therapies.

Predictive Significance of an Optimized Panel for Basal-like Breast Cancer: Results from the Canadian Cancer Trials Group MA.5 and MA.12 Phase III Clinical Trials.

PURPOSE: Accurate IHC biomarkers incorporating nestin positivity or inositol polyphosphate-4-phosphate (INPP4B) loss have recently been optimized to identify the basal-like intrinsic breast cancer subtype regardless of estrogen, progesterone, or Her2 status. We examined the predictive capacity of these basal biomarkers in the CCTG MA.5 chemotherapy and MA.12 endocrine therapy trials. EXPERIMENTAL DESIGN: Formalin-fixed paraffin embedded blocks of primary tumors from patients randomized in the two trials were used to build tissue microarrays. IHC staining for nestin and INPP4B followed published methods and REMARK criteria. A prespecified statistical plan tested the hypothesis that patients with basal breast cancer (nestin+ or INPP4B-) would not benefit from anthracycline substitution in MA.5 or from tamoxifen in MA.12. RESULTS: Nestin positivity or INPP4B loss was observed in 110/453 (24%) interpretable samples from MA.5 and 47/366 (13%) from MA.12, and was associated with high grade, younger age, estrogen receptor negativity, triple-negative, core basal, and PAM50 basal-like subtypes. In the MA.5 trial, patients assigned as basal experienced lower benefit from anthracycline versus nonanthracycline adjuvant chemotherapy [HR, 1.49; 95% confidence interval (CI), 0.72-3.10] when compared with non-basal (nestin- and INPP4B+) cases where there was a higher benefit from anthracyclines (HR, 0.75; 95% CI, 0.54-1.04; P interaction = 0.01). In the MA.12 trial, patients assigned as basal did not demonstrate a benefit from adjuvant tamoxifen versus placebo (HR, 0.48; 95% CI, 0.12-1.86; P = 0.29), whereas nonbasal cases displayed significant benefit (HR, 0.66; 95% CI, 0.45-0.98; P = 0.04), although the interaction test was not significant. CONCLUSIONS: The nestin/INPP4B IHC panel identifies women with basal breast cancers who benefit from nonanthracycline chemotherapy but not endocrine adjuvant treatments.

Cancer Antigen 15-3/Mucin 1 Levels in CCTG MA.32: A Breast Cancer Randomized Trial of Metformin vs Placebo.

Background: Circulating levels of cancer antigen (CA) 15-3, a tumor marker and regulator of cellular metabolism, were reduced by metformin in a nonrandomized neoadjuvant study. We examined the effects of metformin (vs placebo) on CA 15-3 in participants of MA.32, a phase III randomized trial in early-stage breast cancer. Methods: A total of 3649 patients with T1-3, N0-3, M0 breast cancer were randomly assigned; pretreatment and 6-month on-treatment fasting plasma were centrally assayed for CA 15-3. Genomic DNA was analyzed for the rs11212617 single nucleotide polymorphism. Absolute and relative change of CA 15-3 (metformin vs placebo) were compared using Wilcoxon rank and t tests. Regression models adjusted for baseline differences and assessed key interactions. All statistical tests were 2-sided. Results: Mean (SD) age was 52.4 (10.0) years. The majority of patients had T2/3, node-positive, hormone receptor-positive, HER2-negative breast cancer treated with (neo)adjuvant chemotherapy and hormone therapy. Mean (SD) baseline CA 15-3 was 17.7 (7.6) and 18.0 (8.1 U/mL). At 6 months, CA 15-3 was statistically significantly reduced in metformin vs placebo arms (absolute geometric mean reduction in CA 15-3 = 7.7% vs 2.0%, P < .001; relative metformin: placebo level of CA 15-3 [adjusted for age, baseline body mass index, and baseline CA 15-3] = 0.94, 95% confidence interval = 0.92 to 0.96). This reduction was independent of tumor characteristics, perioperative systemic therapy, baseline body mass index, insulin, and the single nucleotide polymorphism status (all Ps > .11). Conclusions: Our observation that metformin reduces CA 15-3 by approximately 6% was corroborated in a large placebo-controlled randomized trial. The clinical implications of this reduction in CA 15-3 will be explored in upcoming efficacy analyses of breast cancer outcomes in MA.32.

A Prospective Economic Analysis of Early Outcome Data From the Alliance A041202/ CCTG CLC.2 Randomized Phase III Trial Of Bendamustine-Rituximab Compared With Ibrutinib-Based Regimens in Untreated Older Patients With Chronic Lymphocytic Leukemia.

INTRODUCTION: The Alliance A041202/CCTG CLC.2 trial demonstrated superior progression-free survival with ibrutinib-based therapy compared to chemoimmunotherapy with bendamustine-rituximab (BR) in previously untreated older patients with chronic lymphocytic leukemia. We completed a prospective trial-based economic analysis of Canadian patients to study the direct medical costs and quality-adjusted benefit associated with these therapies. METHODS: Mean survival was calculated using the restricted mean survival method from randomization to the study time-horizon of 24 months. Health state utilities were collected using the EuroQOL EQ-5D instrument with Canadian tariffs applied to calculate quality-adjusted life years (QALYs). Costs were applied to resource utilization data (expressed in 2019 US dollars). We examined costs and QALYs associated ibrutinib, ibrutinib with rituximab (IR), and BR therapy. RESULTS: A total of 55 patients were enrolled; two patients were excluded from the analysis. On-protocol costs (associated with protocol-specified resource use) were higher for patients receiving ibrutinib (mean $189,335; P < 0.0001) and IR (mean $219,908; P < 0.0001) compared to BR (mean $51,345), driven by higher acquisition costs for ibrutinib. Total mean costs (over 2-years) were $192,615 with ibrutinib, $223,761 with IR, and $55,413 with BR (P < 0.0001 for ibrutinib vs. BR and P < 0.0001 for IR vs. BR). QALYs were similar between the three treatment arms: 1.66 (0.16) for ibrutinib alone, 1.65 (0.24) for IR, and 1.66 (0.17) for BR; therefore, a formal cost-utility analysis was not conducted. CONCLUSIONS: Direct medical costs are higher for patients receiving ibrutinib-based therapies compared to chemoimmunotherapy in frontline chronic lymphocytic leukemia, with the cost of ibrutinib representing a key driver.