Prognostic Impact of Early Treatment and Oxaliplatin Discontinuation in Patients With Stage III Colon Cancer: An ACCENT/IDEA Pooled Analysis of 11 Adjuvant Trials

PURPOSE

Oxaliplatin-based adjuvant chemotherapy in patients with stage III colon cancer (CC) for 6 months remains a standard in high-risk stage III patients. Data are lacking as to whether early discontinuation of all treatment (ETD) or early discontinuation of oxaliplatin (EOD) could worsen the prognosis.

MATERIALS AND METHODS

We studied the prognostic impact of ETD and EOD in patients with stage III CC from the ACCENT/IDEA databases, where patients were planned to receive 6 months of infusional fluorouracil, leucovorin, and oxaliplatin or capecitabine plus oxaliplatin. ETD was defined as discontinuation of treatment and EOD as discontinuation of oxaliplatin only before patients had received a maximum of 75% of planned cycles. Association between ETD/EOD and overall survival and disease-free survival (DFS) were assessed by Cox models adjusted for established prognostic factors.

RESULTS

Analysis of ETD and EOD included 10,447 (20.9% with ETD) and 7,243 (18.8% with EOD) patients, respectively. Compared with patients without ETD or EOD, patients with ETD or EOD were statistically more likely to be women, with Eastern Cooperative Oncology Group performance status ≥ 1, and for ETD, older with a lower body mass index. In multivariable analyses, ETD was associated with a decrease in disease-free survival and overall survival (hazard ratio [HR], 1.61, P < .001 and HR, 1.73, P < .001), which was not the case for EOD (HR, 1.07, P = .3 and HR, 1.13, P = .1). However, patients who received < 50% of the planned cycles of oxaliplatin had poorer outcomes.

CONCLUSION

In patients treated with 6 months of oxaliplatin-based chemotherapy for stage III CC, ETD was associated with poorer oncologic outcomes. However, this was not the case for EOD. These data favor discontinuing oxaliplatin while continuing fluoropyrimidine in individuals with significant neurotoxicity having received > 50% of the planned 6-month chemotherapy.

Conversion of non-inferiority margin from hazard ratio to restricted mean survival time difference using data from multiple historical trials

The restricted mean survival time measure has gained a lot of interests for designing and analyzing oncology trials with time-to-event endpoints due to its intuitive clinical interpretation and potentially high statistical power. In the non-inferiority trial literature, restricted mean survival time has been used as an alternative measure for reanalyzing a completed trial, which was originally designed and analyzed based on traditional proportional hazard model. However, the reanalysis procedure requires a conversion from the non-inferiority margin measured in hazard ratio to a non-inferiority margin measured by restricted mean survival time difference. An existing conversion method assumes a Weibull distribution for the population survival time of the historical active control group under the proportional hazard assumption using data from a single trial. In this article, we develop a methodology for non-inferiority margin conversion when data from multiple historical active control studies are available, and introduce a Kaplan-Meier estimator-based method for the non-inferiority margin conversion to relax the parametric assumption. We report extensive simulation studies to examine the performances of proposed methods under the Weibull data generative models and a piecewise-exponential data generative model that mimic the tumor recurrence and survival characteristics of advanced colon cancer. This work is motivated to achieve non-inferiority margin conversion, using historical patient-level data from a large colon cancer clinical database, to reanalyze an internationally collaborated non-inferiority study that evaluates 6-month versus 3-month duration of adjuvant chemotherapy in stage III colon cancer patients.

Prognostic impact of early treatment discontinuation and early oxaliplatin discontinuation in patients treated with 6 months of oxaliplatin-based adjuvant chemotherapy for stage III colon cancer: an ACCENT/IDEA pooled analysis of 11 trials

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Background: Six months of oxaliplatin-based adjuvant chemotherapy in patients with stage III colon cancer (CC) remains a standard in high-risk stage III patients. Early treatment discontinuation (ETD) could worsen the prognosis. In addition, there is current lack of data on the prognostic impact of early oxaliplatin only discontinuation (EOD). Methods: We studied the prognostic impact of ETD and EOD in patients with stage III CC who participated in 11 relevant clinical trials of the ACCENT and IDEA databases, where patients were planned to receive 6 months of adjuvant fluoropyrimidine plus oxaliplatin (FOLFOX or CAPOX). ETD was defined as discontinuation of treatment before 75% of cycles of chemotherapy. EOD was defined as discontinuation of oxaliplatin only, while continuing the fluoropyrimidine, before 75% of cycles of oxaliplatin. Association between ETD/EOD and overall survival (OS) and disease-free survival (DFS) was assessed by Cox model adjusted for prognostic factors. Results: ETD analysis included 10,444 patients (FOLFOX n = 7,033; CAPOX n = 3,411), with 20.9% of patients with ETD (17.8% with FOLFOX and 27.2% with CAPOX, p < 0.001). Out of 7,243 patients, 18.8% experienced EOD (17.4% FOLFOX versus 21.4% with CAPOX, p < 0.001). Compared to patients without ETD or EOD, patients with ETD or EOD were statistically more likely to be women, older, with higher ECOG-PS ≥ 1, and in addition for ETD, a Body Mass Index (BMI) < 18.5 kg/m2. In multivariate analyses, ETD was associated with a decrease in DFS and OS in the overall population (HR: 1.40 95%CI 1.23-1.58, p < 0.001 and HR: 1.51 95%CI 1.31-1.74, p < 0.001, respectively). The same pattern was present with FOLFOX and CAPOX regimen, and also in low-risk and high-risk groups for each regimen with the exception of the CAPOX regimen in the low-risk group for DFS and OS. By contrast, EOD was not associated with reduced DFS or OS in the overall population (HR: 1.10 95%CI 0.77-1.58, p = 0.6 and HR: 0.97 95%CI 0.62-1.52, p = 0.9, respectively), in the low-risk group (HR: 0.97 95%CI 0.56-1.66, p = 0.9 and HR: 0.97 95%CI 0.51-1.82, p = 0.9, respectively) and high-risk group (HR: 1.22 95%CI 0.74-2.02, p = 0.4 and HR: 1.05 95%CI 0.53-2.08, p = 0.9, respectively) and for all subgroups of regimen. Conclusions: In patients treated with 6 months of oxaliplatin-based adjuvant chemotherapy for stage III CC, ETD was associated with a decrease in DFS and OS. By contrast, EOD was not significantly associated with poorer outcomes. In case of relevant neurotoxicity during a 6 months schedule, these data are not in favor of continuing oxaliplatin beyond 75% of planned cycles of adjuvant chemotherapy, and demonstrate that fluoropyrimidines remain the cornerstone of adjuvant chemotherapy in localized CC.

Early-onset stage II/III colorectal adenocarcinoma in the IDEA database: Treatment adherence, toxicities, and outcomes from adjuvant fluoropyrimidine and oxaliplatin

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Background: Incidence of early-onset colorectal cancer (eoCRC, age < 50) is steadily increasing. Decisions on adjuvant treatment (adjTx) regimen and duration should consider tx adherence, toxicity (tox) and expected outcomes in a population with life-expectancy longer than late onset CRC (loCRC, age ≥ 50). Methods: Individual patient data from stage II/III patients (pts) from 6 randomised trials in the IDEA database were used to compare characteristics, tx adherence, and adverse events of eoCRC to loCRC. To reduce the confounder of non-cancer-related deaths due to age/co-morbidities, time-to-recurrence (TTR) and cancer-specific survival (CSS) were compared by stratified Gay k-sample test. 5-year cancer-specific mortality (CSM) rate were estimated by adjusted cumulative incidence function. 3-year relapse-free survival (RFS) rate were compared by stratified and adjusted COX models. Results: Out of 16,349 pts included, 1564 (9.6%) were eoCRC. Compared to loCRC, eoCRC had lower percent of male pts (51% vs 57%, p < 0.01) better performance status (PS0 86% vs 80%, p < 0.01), similar T stage distribution (% T1-3/T4: 76/24 vs 77/23, p = 0.97), higher rate of N2 disease (24% vs 22%, p < 0.01), more likely to complete pre-planned duration of adjTx (83.2% vs 78.2%, p < 0.01) and received a higher tx intensity especially with 6 month tx (mean oxaliplatin dose intensity 75% vs 72%, p < 0.01; capecitabine 85% vs 78%, p < 0.01; 5FU 85% vs 82% p < 0.01). Gastrointestinal tox was more common in eoCRC (any grade nausea 58% vs 45%, p < 0.01; any grade vomiting 22% vs 16%, p < 0.01); haematological tox was more frequent in loCRC (62% vs, 69%, p = < 0.01); any grade neuropathy rate was similar (75%). Significant interaction was found between age and T stage for TTR (p = 0.04). Clinical outcome estimates and comparisons are shown in Table. Notably, high risk stage III (T4/N2) eoCRC had significantly lower 3-y RFS rate (54% vs 64%, HRadj 0.74, p < 0.01). Conclusions: eoCRC have better tx adherence than loCRC, as expected. While in high risk stage II and low risk stage III, cancer-specific outcomes are not different, in high risk stage III young age is negatively prognostic and associated with significantly higher relapse rate and risk of CRC death; this is despite a higher administered adjTx-intensity, suggesting a more aggressive disease biology. Clinical trial information: NCT00749450 (SCOT); NCT00646607 (TOSCA); NCT01150045 (CALGB/SWOG 80702); NCT00958737 (IDEA France) [Table: see text]

Randomized Phase II Trial of Polyphenon E versus Placebo in Patients at High Risk of Recurrent Colonic Neoplasia

Polyphenon E (Poly E) is a green tea polyphenol preparation whose most active component is epigallocatechin gallate (EGCG). We studied the cancer preventive efficacy and safety of Poly E in subjects with rectal aberrant crypt foci (ACF), which represent putative precursors of colorectal cancers. Eligible subjects had prior colorectal advanced adenomas or cancers, and had ≥5 rectal ACF at a preregistration chromoendoscopy. Subjects (N = 39) were randomized to 6 months of oral Poly E (780 mg EGCG) daily or placebo. Baseline characteristics were similar by treatment arm (all P >0.41); 32 of 39 (82%) subjects completed 6 months of treatment. The primary endpoint was percent reduction in rectal ACF at chromoendoscopy comparing before and after treatment. Among 32 subjects (15 Poly E, 17 placebo), percent change in rectal ACF number (baseline vs. 6 months) did not differ significantly between study arms (3.7% difference of means; P = 0.28); total ACF burden was also similar (-2.3% difference of means; P = 0.83). Adenoma recurrence rates at 6 months were similar by arm (P > 0.35). Total drug received did not differ significantly by study arm; 31 (79%) subjects received ≥70% of prescribed Poly E. Poly E was well tolerated and adverse events (AE) did not differ significantly by arm. One subject on placebo had two grade 3 AEs; one subject had grade 2 hepatic transaminase elevations attributed to treatment. In conclusion, Poly E for 6 months did not significantly reduce rectal ACF number relative to placebo. Poly E was well tolerated and without significant toxicity at the dose studied. PREVENTION RELEVANCE: We report a chemoprevention trial of polyphenon E in subjects at high risk of colorectal cancer. The results show that polyphenon E was well tolerated, but did not significantly reduce the number of rectal aberrant crypt foci, a surrogate endpoint biomarker of colorectal cancer.

Duration of Adjuvant Doublet Chemotherapy (3 or 6 months) in Patients With High-Risk Stage II Colorectal Cancer

PURPOSE

As oxaliplatin results in cumulative neurotoxicity, reducing treatment duration without loss of efficacy would benefit patients and healthcare providers.

PATIENTS AND METHODS

Four of the six studies in the International Duration of Adjuvant Chemotherapy (IDEA) collaboration included patients with high-risk stage II colon and rectal cancers. Patients were treated (clinician and/or patient choice) with either fluorouracil, leucovorin, and oxaliplatin (FOLFOX) or capecitabine and oxaliplatin (CAPOX) and randomly assigned to receive 3- or 6-month treatment. The primary end point is disease-free survival (DFS), and noninferiority of 3-month treatment was defined as a hazard ratio (HR) of < 1.2- v 6-month arm. To detect this with 80% power at a one-sided type one error rate of 0.10, a total of 542 DFS events were required.

RESULTS

3,273 eligible patients were randomly assigned to either 3- or 6-month treatment with 62% receiving CAPOX and 38% FOLFOX. There were 553 DFS events. Five-year DFS was 80.7% and 83.9% for 3-month and 6-month treatment, respectively (HR, 1.17; 80% CI, 1.05 to 1.31; P [for noninferiority] .39). This crossed the noninferiority limit of 1.2. As in the IDEA stage III analysis, the duration effect appeared dependent on the chemotherapy regimen although a test of interaction was negative. HR for CAPOX was 1.02 (80% CI, 0.88 to 1.17), and HR for FOLFOX was 1.41 (80% CI, 1.18 to 1.68).

CONCLUSION

Although noninferiority has not been demonstrated in the overall population, the convenience, reduced toxicity, and cost of 3-month adjuvant CAPOX suggest it as a potential option for high-risk stage II colon cancer if oxaliplatin-based chemotherapy is suitable. The relative contribution of the factors used to define high-risk stage II disease needs better understanding.

Prognostic value of tumor deposits in stage III colon cancer patients, a post-hoc analysis of CALGB/SWOG 80702 phase III study

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Background: In colon cancer, tumor deposits (TD) have been associated with worse prognosis, but they are included in the TNM staging system only in the absence of lymph node metastasis (i.e., stage III pN1c tumors). Here we aimed at evaluating the prognostic value of TD and the impact of the addition of TD in the count of lymph node metastases in patients with stage III colon cancer from the CALGB/SWOG 80702 phase III trial (NCT01150045). Methods: Pathological reports of all patients were reviewed for the presence and the count of TD, primary tumor sidedness, lymphovascular invasion and perineural invasion. Cases without available pathological report or without specific information of TD were excluded. Prognostic associations were evaluated by multi-variable Cox models adjusting for treatment arm, T-stage, N-stage, lymphovascular invasion, perineural invasion and lymph node ratio. Results: Overall, 2028 patients were included, with 524 (26%) TD-positive and 1504 (74%) TD-negative stage III tumors. Of the TD-positive patients, 80 (15.4%) were node negative (i.e., pN1c), 239 (46.1%) were pN1a/b and 200 (38.55%) were pN2. 17.2% and 37.0% of all pN1a/b and pN2 tumors had TD. Overall median follow-up was 69.3 months. The presence of TD was associated with poorer DFS (adjusted hazard ratio (aHR) = 1.59, 95%CI 1.28-1.91) and OS (aHR = 1.52, 95%CI 1.18-1.95) in the overall population. The negative effect of TD on DFS and OS was observed for both pN1a/b and pN2 groups and confirmed in multivariate Cox model. Among TD-positive patients, the number of TD had a linear negative effect on DFS and OS. Adding TD to the count of lymph node metastases, 104 of 1570 (6.6%) patients initially considered as pN1 were re-staged as pN2. Re-staged pN2 patients experienced worse DFS (3-year DFS rate: 65.5% versus 80.3%, P = .0003) and OS (5-year OS rate: 69.1 versus 87.8%, P = .0005) than patients confirmed as pN1. Re-staged pN2 patients had similar DFS than patients initially staged as pN2 (3-year DFS rate: 65.5% versus 63.1%, P = .1992). OS curves of these 2 groups crossed, with better outcomes during the first 3 years of follow-up but poorer 5-year estimates for re-staged pN2 patients (5-year OS rate: 69.1% versus 74.8%, P = .0436). Conclusions: TD are found in more than one fourth of stage III colon cancer specimens. The number of TD has a linear deleterious effect on patients’ prognosis. Adding the number of TD to the count of lymph node metastases improves the prognostication accuracy of the TNM staging. Support: U10CA180821, U10CA180882; https://acknowledgments.alliancefound.org . Clinical trial information: NCT01150045.

Alliance A021501: Preoperative mFOLFIRINOX or mFOLFIRINOX plus hypofractionated radiation therapy (RT) for borderline resectable (BR) adenocarcinoma of the pancreas

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Background: Neoadjuvant therapy has been associated with a median overall survival (OS) of 18 – 23 months (mo) in patients (pts) with BR pancreatic ductal adenocarcinoma (PDAC). To establish reference regimens to which novel treatments can be compared in future studies, we evaluated neoadjuvant mFOLFIRINOX with or without RT in BR PDAC in a phase II National Clinical Trials Network (NCTN) trial. Methods: Pts with ECOG PS 0-1 and BR PDAC confirmed by central real-time radiographic review after pre-registration were randomized to either arm A: 8 cycles of neoadjuvant mFOLFIRINOX (oxaliplatin 85 mg/m2, irinotecan 180 mg/m2, leucovorin 400 mg/m2 and infusional 5-fluorouracil 2400 mg/m2 over 46 hours), or arm B: 7 cycles of mFOLFIRINOX followed by stereotactic body RT (SBRT, 33-40 Gy in 5 fractions [fx]) or hypofractionated image guided RT (HIGRT, 25 Gy in 5 fx). Pts in either arm without disease progression underwent pancreatectomy, then 4 cycles of adjuvant mFOLFOX6 (oxaliplatin 85 mg/m2, leucovorin 400 mg/m2 and infusional 5-fluorouracil 2400 mg/m2 over 46 hours). The primary endpoint, 18-mo OS rate, of each arm was compared to a historical control of 50%. Planned interim analysis mandated closure of either arm in which <11 of first 30 accrued pts underwent R0 resection. Results: 155 pts pre-registered and 126 pts were enrolled to arm A (N=70; 54 randomized, 16 following closure of arm B) or arm B (N=56; closed at interim analysis, all pts randomized prior to closure). Median age (A: 63y, B: 67y), median CA 19-9 level (A: 171 U/ml, B: 248 U/ml) and ECOG PS (A: 51% PS 0, B: 57% PS 0) of registered pts were similar between arms (p > 0.05). Treatment detailed in Table. The 18-mo OS rate based on Kaplan Meier estimates was 67.9% (95%CI: 54.6 – 78.0) in arm A and 47.3% (95%CI: 33.7 – 59.7) in arm B. Among pts who underwent pancreatectomy, 18-mo OS rate was 93.1% (95%CI: 84.3 – 100) and 78.9% (95%CI: 62.6 – 99.6) in arm A and B, respectively. With median follow-up of 27 and 31 mo, median OS was 31.0 (95%CI: 22.2 – NE) mo and 17.1 (95%CI: 12.8 – 24.4) mo in arm A and B, respectively. Conclusions: Neoadjuvant mFOLFIRINOX was associated with favorable OS relative to historical data in pts with BL PDAC in this phase II NCTN trial. mFOLFIRINOX with hypofractionated RT did not improve OS compared to historical data. mFOLFIRINOX represents a reference regimen in this setting and a backbone on which to add novel agents. Support: U10CA180821, U10CA180882, U24CA196171; https://acknowledgments.alliancefound.org Clinical trial information: NCT02839343. [Table: see text]

Overall survival (OS) and long-term disease-free survival (DFS) of three versus six months of adjuvant (adj) oxaliplatin and fluoropyrimidine-based therapy for patients (pts) with stage III colon cancer (CC): Final results from the IDEA (International Duration Evaluation of Adj chemotherapy) collaboration

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Background: In overall population, IDEA pooled analysis did not demonstrate non-inferiority (NI) regarding 3y DFS in pts with stage III CC receiving 3m vs. 6m of adj FOLFOX/CAPOX. However, in pts treated with CAPOX (especially in low-risk pts), 3m of therapy was as effective as 6m. Results of OS and 5y DFS are reported. Methods: OS was defined as time from enrollment to death due to all causes. OS NI margin was conservatively set to be Hazard Ratio (HR) = 1.11, which is equivalent to: the maximum acceptable loss of OS efficacy, by shortening treatment to 3m, was half of the OS efficacy gained in MOSAIC trial (i.e., 2.26% absolute reduction in 5y OS rate). Pre-planned sub-group analyses included by regimen and risk group for both OS and 5y DFS. NI was to be declared if the one-sided false discovery rate adjusted (FDRa) NI p-value < 0.025. Results: With an overall median survival follow-up of 72 m (range per study, 62 to 84 m), 2584 deaths and 3777 DFS events among 12,835 pts from six trials were observed. Across 6 studies, 39.5% of pts received CAPOX (rate by study, 0% to 75.1%). Overall, the 5y OS rate was 82.4% (3m) and 82.8% (6m), with estimated OS HR of 1.02 (95% confidence interval [CI], 0.95-1.11; FDRa NI p, 0.058) and absolute 5-y OS rate difference of -0.4% (95% CI, -2.1 to 1.3%). Overall, the 5y DFS rate was 69.1% (3m) and 70.8% (6m), with estimated DFS HR of 1.08 (95%CI, 1.01-1.15, FDRa NI p, 0.22). HRs (95% CI) within subgroups see table. Conclusions: 5y OS rate reported in IDEA trials was higher than historical rates, regardless of duration of therapy. While overall survival in IDEA did not meet prior statistical assumptions for NI in overall population, the 0.4% difference in 5y OS should be placed in clinical context. OS and 5y DFS results continue to support the use of 3m adjuvant CAPOX for the vast majority of stage III colon cancer pts. This conclusion is strengthened by the substantial reduction of toxicities, inconveniencies and cost associated with shorter treatment duration. Clinical trial information: NCT01150045; 2009-010384-16; NCT00749450; ISRCTN59757862; 2007-003957-10; UMIN000008543; 2007-000354 . [Table: see text]

Clinical Outcomes in Patients With Colon Cancer With Microsatellite Instability of Sporadic or Familial Origin Treated With Adjuvant FOLFOX With or Without Cetuximab: A Pooled Analysis of the PETACC8 and N0147 Trials

PURPOSE

The microsatellite instability (MSI) or deficient mismatch repair (dMMR) phenotype is usually regarded as a single biologic entity, given the absence of comparative analyses regarding prognosis and response to chemotherapy between sporadic and familial dMMR cancers.

PATIENTS AND METHODS

Patients with stage III colon cancers were randomly assigned to FOLFOX (leucovorin, fluorouracil, and oxaliplatin) with or without cetuximab in 2 large adjuvant phase III trials (N = 5,577). Among patients with MSI and KRAS exon 2 wild-type (WT) tumors, the prognostic and predictive impacts of sporadic versus familial dMMR cancers and BRAF V600E mutational status were determined. Multivariable Cox proportional hazards models were used to assess disease-free survival (DFS) by treatment arm, adjusting for age, sex, tumor grade, Eastern Cooperative Oncology Group performance status, pT/pN stage, and primary tumor location.

RESULTS

Among patients with MSI status with complete data for dMMR mechanism analysis (n = 354), 255 (72%) had sporadic (BRAF mutation and/or MLH1 methylation) and 99 (28%) had familial tumors (BRAF WT and unmethylated MLH1 or loss of MSH2/MSH6/PMS2 protein expression). A large proportion of dMMR sporadic tumors were mutated for BRAF (n = 200). In patients treated with FOLFOX, DFS did not differ statistically by dMMR mechanism, whereas in patients treated with FOLFOX plus cetuximab, those with sporadic tumors had worse DFS than those with familial cancers (multivariable hazard ratio, 2.69; 95% CI, 1.02 to 7.08; P = .04). Considering the predictive utility, the interaction between treatment and dMMR mechanism was significant (P = .03). Furthermore, a nonsignificant trend toward a deleterious effect of adding cetuximab to FOLFOX was observed in patients with BRAF-mutant but not BRAF WT tumors.

CONCLUSION

The addition of cetuximab to adjuvant FOLFOX was associated with shorter DFS in patients with sporadic dMMR colon cancer. Additional studies are needed to validate these results in metastatic disease.

Role of Deficient DNA Mismatch Repair Status in Patients With Stage III Colon Cancer Treated With FOLFOX Adjuvant Chemotherapy: A Pooled Analysis From 2 Randomized Clinical Trials

Importance

The prognostic impact of DNA mismatch repair (MMR) status in stage III colon cancer patients receiving FOLFOX (folinic acid, fluorouracil, and oxaliplatin) adjuvant chemotherapy remains controversial.

Objective

To determine the association of MMR status with disease-free survival (DFS) in patients with stage III colon cancer treated with FOLFOX.

Design, Setting, and Participants

The evaluated biomarkers for MMR status were determined from prospectively collected tumor blocks from patients treated with FOLFOX in 2 open-label, phase 3 randomized clinical trials: NCCTG N0147 and PETACC8. The studies were conducted in general community practices, private practices, and institutional practices in the United States and Europe. All participants had stage III colon adenocarcinoma. They were enrolled in NCCTG N0147 from February 2004 to November 2009 and in PETACC8 from December 2005 to November 2009.

Interventions

Patients in the clinical trials were randomly assigned to receive 6 months of chemotherapy with FOLFOX or FOLFOX plus cetuximab. Only those patients treated with FOLFOX alone were included in the present study.

Main Outcomes and Measures

Association of MMR status with DFS was analyzed using a stratified Cox proportional hazards model. Multivariable models were adjusted for age, sex, tumor grade, pT/pN stage, tumor location, ECOG (Eastern Cooperative Oncology Group) performance status, and BRAF V600E mutational status.

Results

Among 2636 patients with stage III colon cancer treated with FOLFOX, MMR status was available for 2501. Of these, 252 (10.1%) showed deficient MMR status (dMMR; 134 women, 118 men; median age, 59 years), while 2249 (89.9%) showed proficient MMR status (pMMR; 1020 women, 1229 men; median age, 59 years). The 3-year DFS rates in the dMMR and pMMR groups were 75.6% and 74.4%, respectively. By multivariate analysis, patients with dMMR phenotype had significantly longer DFS than those with pMMR (adjusted hazard ratio, 0.73; 95% CI, 0.54-0.97; P = .03).

Conclusions and Relevance

The deficient MMR phenotype remains a favorable prognostic factor in patients with stage III colon cancer receiving FOLFOX adjuvant chemotherapy.

Trial Registration

clinicaltrials.gov Identifier: NCT00079274 for the NCCTG N0147 trial and EudraCT identifier: 2005-003463-23 for the PETACC8 trial.

Efficacy of Difluoromethylornithine and Aspirin for Treatment of Adenomas and Aberrant Crypt Foci in Patients with Prior Advanced Colorectal Neoplasms

Difluoromethylornithine (DFMO), an inhibitor of polyamine synthesis, was shown to act synergistically with a NSAID for chemoprevention of colorectal neoplasia. We determined the efficacy and safety of DFMO plus aspirin for prevention of colorectal adenomas and regression of rectal aberrant crypt foci (ACF) in patients with prior advanced adenomas or cancer. A double-blinded, placebo-controlled trial was performed in 104 subjects (age 46-83) randomized (1:1) to receive daily DFMO (500 mg orally) plus aspirin (325 mg) or matched placebos for one year. All polyps were removed at baseline. Adenoma number (primary endpoint) and rectal ACF (index cluster and total) were evaluated at a one year colonoscopy. ACF were identified by chromoendoscopy. Toxicity was monitored, including audiometry. Eighty-seven subjects were evaluable for adenomas or ACF modulation (n = 62). At one year of treatment, adenomas were detected in 16 (38.1%) subjects in the DFMO plus aspirin arm (n = 42) versus 18 (40.9%) in the placebo arm (n = 44; P = 0.790); advanced adenomas were similar (n = 3/arm). DFMO plus aspirin was associated with a statistically significant reduction in the median number of rectal ACF compared with placebo (P = 0.036). Total rectal ACF burden was also reduced in the treatment versus the placebo arm relative to baseline (74% vs. 45%, P = 0.020). No increase in adverse events, including ototoxicity, was observed in the treatment versus placebo arms. While adenoma recurrence was not significantly reduced by one year of DFMO plus aspirin, the drug combination significantly reduced rectal ACF number consistent with a chemopreventive effect.

Regorafenib dose-optimisation in patients with refractory metastatic colorectal cancer (ReDOS): a randomised, multicentre, open-label, phase 2 study

BACKGROUND

Regorafenib confers an overall survival benefit in patients with refractory metastatic colorectal cancer; however, the adverse event profile of regorafenib has limited its use. Despite no supportive evidence, various dosing schedules are used clinically to alleviate toxicities. This study evaluated the safety and activity of two regorafenib dosing schedules.

METHODS

In this randomised, multicentre, open-label, phase 2 study done in 39 outpatient cancer centres in the USA, adults aged 18 years or older with histologically or cytologically confirmed advanced or metastatic adenocarcinoma of the colon or rectum that was refractory to previous standard therapy, including EGFR inhibitors if KRAS wild-type, were enrolled. Eligible patients had an Eastern Cooperative Oncology Group performance status of 0-1 and had no previous treatment with regorafenib. Patients were randomly assigned (1:1:1:1) into four groups with two distinct regorafenib dosing strategies and two clobetasol usage plans, stratified by hospital. Regorafenib dosing strategies were a dose-escalation strategy (starting dose 80 mg/day orally with weekly escalation, per 40 mg increment, to 160 mg/day regorafenib) if no significant drug-related adverse events occurred and a standard-dose strategy (160 mg/day orally) for 21 days of a 28-day cycle. Clobetasol usage plans (0·05% clobetasol cream twice daily applied to palms and soles) were either pre-emptive or reactive. After randomisation to the four preplanned groups, using the Pocock and Simon dynamic allocation procedures stratified by the treating hospitals, we formally tested the interaction between the two interventions, dosing strategy and clobetasol usage. Given the absence of a significant interaction (p=0·74), we decided to pool the data for the pre-emptive and reactive treatment with clobetasol and compared the two dosing strategies (dose escalation vs standard dose). The primary endpoint was the proportion of evaluable patients (defined as those who were eligible, consented, and received any protocol treatment) initiating cycle 3 and was analysed per protocol. Superiority for dose escalation was declared if the one-sided p value with Fisher's exact test was less than 0·2. This trial is registered with ClinicalTrials.gov, number NCT02368886. This study is fully accrued but remains active.

FINDINGS

Between June 2, 2015, and June 22, 2017, 123 patients were randomly assigned to treatment, of whom 116 (94%) were evaluable. The per-protocol population consisted of 54 patients in the dose-escalation group and 62 in the standard-dose group. At data cutoff on July 24, 2018, median follow-up was 1·18 years (IQR 0·98-1·57). The primary endpoint was met: 23 (43%, 95% CI 29-56) of 54 patients in the dose-escalation group initiated cycle 3 versus 16 (26%, 15-37) of 62 patients in the standard-dose group (one-sided p=0·043). The most common grade 3-4 adverse events were fatigue (seven [13%] patients in the dose-escalation group vs 11 [18%] in the standard-dose group), hand-foot skin reaction (eight [15%] patients vs ten [16%] patients), abdominal pain (nine [17%] patients vs four [6%] patients), and hypertension (four [7%] patients vs nine [15%] patients). 14 patients had at least one drug-related serious adverse event: six patients in the dose-escalation group and eight patients in the standard-dose group. There was one probable treatment-related death in the standard-dose group (myocardial infarction).

INTERPRETATION

The dose-escalation dosing strategy represents an alternative approach for optimising regorafenib dosing with comparable activity and lower incidence of adverse events and could be implemented in clinical practice on the basis of these data.

FUNDING

Bayer HealthCare Pharmaceuticals.

A nomogram for predicting survival and retroperitoneal lymph node dissection treatment in patients with resected testicular germ cell tumors

BACKGROUND AND OBJECTIVES

To build nomogram incorporating potential prognostic factors for predicting survival outcomes of testicular germ cell tumors (TGCT) patients after resection of the primary tumor.

METHODS

Data of TGCT patients from the Surveillance, Epidemiology, and End Results database (2010-2016) who underwent resection of the primary tumor were collected. Overall survival (OS) and cancer-specific survival (CSS) were analyzed by using Cox regression models, nomogram, Kaplan-Meier method, and log-rank test.

RESULTS

We identified 7272 TGCT patients. Age at diagnosis, histology, tumor size, American Joint Committee on Cancer (AJCC) staging system, and number of metastases sites were independent prognostic factors and were integrated into nomograms. The nomograms had higher C-indexes for both OS and CSS compared with the AJCC 7th staging system (0.881 vs 0.831 and 0.895 vs 0.856, respectively). Moreover, the new stratification of risk groups based on the nomograms showed a more significant distinction between Kaplan-Meier curves for survival outcomes than the AJCC staging system. Retroperitoneal lymph node dissection was associated with statistically improved survival probability in the nomogram middle-risk group in resected TGCT patients.

CONCLUSION

The novel nomogram-based staging system could provide satisfactory risk stratification and survival prediction ability beyond traditional AJCC staging systems.

Is the predictive and prognostic impact of sporadic and familial microsatellite instable stage III colon cancer different? A pooled analysis of the PETACC8 and NCCTG N0147 (Alliance) trials

3583

Background: The Microsatellite instability (MSI) or deficient mismatch repair (dMMR) phenotype is usually taken as a single biological entity whereas no data are available concerning prognosis and response to chemotherapy between sporadic and familial dMMR cases. Methods: Resected KRAS exon 2 wild-type (WT) tumor stage III colon cancers (N = 4596) from patients (pts) randomly assigned to FOLFOX +/- cetuximab in two adjuvant large phase III trials were prospectively analyzed for MSI status and dMMR mechanism (sporadic vs familial). Stratified Cox models were used to assess prognostic and predictive values of dMMR mechanism by treatment arms, adjusting for age, gender, tumor grade, ECOG PS, pT/pN stage and primary tumor location. Results: Among dMMR patients with complete data for dMMR mechanism analysis (N = 354), there were 255 (72%) sporadic ( BRAF mutated or WT with MLH1 methylation) and 99 (28%) familial (loss of MSH2 or MSH6, or loss MLH1 with BRAF WT and unmethylated MLH1) cases. A large proportion of dMMR sporadic cases were mutated for BRAF (n = 200; 80%). In pts treated with FOLFOX, the disease-free survival (DFS) was not statistically different by dMMR mechanism, while for pts treated with FOLFOX + cetuximab, the sporadic cases did worse than familial cases (DFS; adjusted (adj) HR, 2.69; 95% CI, 1.02-7.08; P= 0.04). Considering the predictive value, a deleterious effect of adding cetuximab to FOLFOX was observed in sporadic (DFS; adjHR, 1.68; 95% CI, 1.01-2.79; P= 0.04) but not in familial dMMR pts (interaction P value regarding treatment effect = 0.03). Furthermore, a non-significant trend to a deleterious effect of adding cetuximab to FOLFOX was observed in BRAF mutant (DFS; adjHR, 1.66; 95% CI, 0.95-2.92; P= 0.07) but not in BRAF WT pts. Conclusions: The addition of cetuximab to FOLFOX was associated with reduced DFS in patients with sporadic dMMR cases. Further studies including the methylator phenotype (CIMP) analysis are needed to validate these results. Clinical trial information: NCT00265811 and NCT00079274.

A Phase II Randomized Trial of Panitumumab, Erlotinib, and Gemcitabine Versus Erlotinib and Gemcitabine in Patients with Untreated, Metastatic Pancreatic Adenocarcinoma: North Central Cancer Treatment Group Trial N064B (Alliance)

LESSONS LEARNED

Dual epidermal growth factor receptor (EGFR)-directed therapy with erlotinib and panitumumab in combination with gemcitabine was superior to gemcitabine and erlotinib, but the clinical relevance is uncertain given the limited role of gemcitabine monotherapy.A significantly longer overall survival was observed in patients receiving the dual EGFR-directed therapy.The dual EGFR-directed therapy resulted in increased toxicity.

BACKGROUND

Gemcitabine is active in patients with advanced pancreatic adenocarcinoma. The combination of erlotinib, an oral epidermal growth factor receptor (EGFR) inhibitor, and gemcitabine was shown to modestly prolong overall survival when compared with gemcitabine alone. The North Central Cancer Treatment Group (now part of Alliance for Clinical Trials in Oncology) trial N064B compared gemcitabine plus erlotinib versus gemcitabine plus combined EGFR inhibition with erlotinib and panitumumab.

METHODS

Eligible patients with metastatic adenocarcinoma of the pancreas were randomized to either gemcitabine 1,000 mg/m2 on days 1, 8, and 15 of a 28-day cycle with erlotinib 100 mg p.o. daily (Arm A) or the same combination with the addition of panitumumab 4 mg/kg on days 1 and 15 of a 28-day cycle (Arm B). The primary endpoint of the trial was overall survival. Secondary endpoints included progression-free survival, the confirmed response rate, and toxicity. Comparison between arms for the primary endpoint was done with a one-sided log-rank test, and a p value less than .20 was considered statistically significant. Response rate comparison was done with Fisher's exact test. All other reported p values are two-sided.

RESULTS

A total of 92 patients were randomized, 46 to each arm. The median overall survival was 4.2 months in Arm A and 8.3 months in Arm B (hazard ratio, 0.817; 95% confidence interval [CI], 0.530-1.260; p = .1792). The progression-free survival was 2.0 months in Arm A and 3.6 months in Arm B (hazard ratio, 0.843; 95% CI, 0.555-1.280; p = .4190). A partial confirmed response was seen in 8.7% of patients on Arm A and 6.5% on Arm B (p = .9999). No patients had a complete response. Grade 3 and higher nonhematologic toxicities were more common in patients on Arm B compared with those on Arm A (82.6% vs. 52.2%; p = .0018).

CONCLUSION

Dual EGFR-directed therapy resulted in a significant prolongation of overall survival in patients with advanced adenocarcinoma of the pancreas but was associated with substantially increased toxicities. Dual EGFR-directed therapy in combination with gemcitabine alone cannot be recommended for further study, as single-agent gemcitabine is no longer considered an appropriate therapy for otherwise fit patients with metastatic pancreatic cancer.

Feasibility of Implementing the Patient-Reported Outcomes Version of the Common Terminology Criteria for Adverse Events in a Multicenter Trial: NCCTG N1048

Purpose The US National Cancer Institute (NCI) Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE) was developed to enable patient reporting of symptomatic adverse events in oncology clinical research. This study was designed to assess the feasibility and resource requirements associated with implementing PRO-CTCAE in a multicenter trial. Methods Patients with locally advanced rectal cancer enrolled in the National Cancer Institute-sponsored North Central Cancer Treatment Group (Alliance) Preoperative Radiation or Selective Preoperative Radiation and Evaluation before Chemotherapy and Total Mesorectal Excision trial were asked to self-report 30 PRO-CTCAE items weekly from home during preoperative therapy, and every 6 months after surgery, via either the Web or an automated telephone system. If participants did not self-report within 3 days, a central coordinator called them to complete the items. Compliance was defined as the proportion of participants who completed PRO-CTCAE assessments at expected time points. Results The prespecified PRO-CTCAE analysis was conducted after the 500th patient completed the 6-month follow-up (median age, 56 years; 33% female; 12% nonwhite; 43% high school education or less; 5% Spanish speaking), across 165 sites. PRO-CTCAE was reported by participants at 4,491 of 4,882 expected preoperative time points (92.0% compliance), of which 3,771 (77.2%) were self-reported by participants and 720 (14.7%) were collected via central coordinator backup. Compliance at 6-month post-treatment follow-up was 333 of 468 (71.2%), with 122 (26.1%) via backup. Site research associates spent a median of 15 minutes on PRO-CTCAE work for each patient visit. Work by a central coordinator required a 50% time commitment. Conclusion Home-based reporting of PRO-CTCAE in a multicenter trial is feasible, with high patient compliance and low site administrative requirements. PRO-CTCAE data capture is improved through centralized backup calls.

Personalizing Survival Predictions in Advanced Colorectal Cancer: The ARCAD Nomogram Project

Background

Estimating prognosis on the basis of clinicopathologic factors can inform clinical practice and improve risk stratification for clinical trials. We constructed prognostic nomograms for one-year overall survival and six-month progression-free survival in metastatic colorectal carcinoma by using the ARCAD database.

Methods

Data from 22 674 patients in 26 randomized phase III clinical trials since 1997 were used to construct and validate Cox models, stratified by treatment arm within each study. Candidate variables included baseline age, sex, body mass index, performance status, colon vs rectal cancer, prior chemotherapy, number and location of metastatic sites, tumor mutation status (BRAF, KRAS), bilirubin, albumin, white blood cell count, hemoglobin, platelets, absolute neutrophil count, and derived neutrophil-to-lymphocyte ratio. Missing data (<11%) were imputed, continuous variables modeled with splines, and clinically relevant pairwise interactions tested if P values were less than .001. Final models were internally validated via bootstrapping to obtain optimism-corrected calibration and discrimination C-indices, and externally validated on a 10% holdout sample from each trial (n = 2257).

Results

In final models, all included variables were associated with overall survival except for lung metastases, and all but total white cell count associated with progression-free survival. No clinically relevant pairwise interactions were identified. Final nomogram calibration was good (C = 0.68 for overall and C = 0.62 for progression-free survival), as was external validity (concordance between predicted >50% vs < 50% probability) and actual (yes/no) survival (72.8% and 68.2% concordance, respectively, for one-year overall and six-month progression-free survival, between predicted [>50% vs < 50% probability] and actual [yes/no] overall and progression-free survival). Median survival predictions fell within the actual 95% Kaplan-Meier confidence intervals.

Conclusions

The nomograms are well calibrated and internally and externally valid. They have the potential to aid prognostication and patient-physician communication and balance risk in colorectal cancer trials.

International validation of the consensus Immunoscore for the classification of colon cancer: a prognostic and accuracy study

BACKGROUND

The estimation of risk of recurrence for patients with colon carcinoma must be improved. A robust immune score quantification is needed to introduce immune parameters into cancer classification. The aim of the study was to assess the prognostic value of total tumour-infiltrating T-cell counts and cytotoxic tumour-infiltrating T-cells counts with the consensus Immunoscore assay in patients with stage I-III colon cancer.

METHODS

An international consortium of 14 centres in 13 countries, led by the Society for Immunotherapy of Cancer, assessed the Immunoscore assay in patients with TNM stage I-III colon cancer. Patients were randomly assigned to a training set, an internal validation set, or an external validation set. Paraffin sections of the colon tumour and invasive margin from each patient were processed by immunohistochemistry, and the densities of CD3+ and cytotoxic CD8+ T cells in the tumour and in the invasive margin were quantified by digital pathology. An Immunoscore for each patient was derived from the mean of four density percentiles. The primary endpoint was to evaluate the prognostic value of the Immunoscore for time to recurrence, defined as time from surgery to disease recurrence. Stratified multivariable Cox models were used to assess the associations between Immunoscore and outcomes, adjusting for potential confounders. Harrell's C-statistics was used to assess model performance.

FINDINGS

Tissue samples from 3539 patients were processed, and samples from 2681 patients were included in the analyses after quality controls (700 patients in the training set, 636 patients in the internal validation set, and 1345 patients in the external validation set). The Immunoscore assay showed a high level of reproducibility between observers and centres (r=0·97 for colon tumour; r=0·97 for invasive margin; p<0·0001). In the training set, patients with a high Immunoscore had the lowest risk of recurrence at 5 years (14 [8%] patients with a high Immunoscore vs 65 (19%) patients with an intermediate Immunoscore vs 51 (32%) patients with a low Immunoscore; hazard ratio [HR] for high vs low Immunoscore 0·20, 95% CI 0·10-0·38; p<0·0001). The findings were confirmed in the two validation sets (n=1981). In the stratified Cox multivariable analysis, the Immunoscore association with time to recurrence was independent of patient age, sex, T stage, N stage, microsatellite instability, and existing prognostic factors (p<0·0001). Of 1434 patients with stage II cancer, the difference in risk of recurrence at 5 years was significant (HR for high vs low Immunoscore 0·33, 95% CI 0·21-0·52; p<0·0001), including in Cox multivariable analysis (p<0·0001). Immunoscore had the highest relative contribution to the risk of all clinical parameters, including the American Joint Committee on Cancer and Union for International Cancer Control TNM classification system.

INTERPRETATION

The Immunoscore provides a reliable estimate of the risk of recurrence in patients with colon cancer. These results support the implementation of the consensus Immunoscore as a new component of a TNM-Immune classification of cancer.

FUNDING

French National Institute of Health and Medical Research, the LabEx Immuno-oncology, the Transcan ERAnet Immunoscore European project, Association pour la Recherche contre le Cancer, CARPEM, AP-HP, Institut National du Cancer, Italian Association for Cancer Research, national grants and the Society for Immunotherapy of Cancer.

Duration of Adjuvant Chemotherapy for Stage III Colon Cancer

BACKGROUND

Since 2004, a regimen of 6 months of treatment with oxaliplatin plus a fluoropyrimidine has been standard adjuvant therapy in patients with stage III colon cancer. However, since oxaliplatin is associated with cumulative neurotoxicity, a shorter duration of therapy could spare toxic effects and health expenditures.

METHODS

We performed a prospective, preplanned, pooled analysis of six randomized, phase 3 trials that were conducted concurrently to evaluate the noninferiority of adjuvant therapy with either FOLFOX (fluorouracil, leucovorin, and oxaliplatin) or CAPOX (capecitabine and oxaliplatin) administered for 3 months, as compared with 6 months. The primary end point was the rate of disease-free survival at 3 years. Noninferiority of 3 months versus 6 months of therapy could be claimed if the upper limit of the two-sided 95% confidence interval of the hazard ratio did not exceed 1.12.

RESULTS

After 3263 events of disease recurrence or death had been reported in 12,834 patients, the noninferiority of 3 months of treatment versus 6 months was not confirmed in the overall study population (hazard ratio, 1.07; 95% confidence interval [CI], 1.00 to 1.15). Noninferiority of the shorter regimen was seen for CAPOX (hazard ratio, 0.95; 95% CI, 0.85 to 1.06) but not for FOLFOX (hazard ratio, 1.16; 95% CI, 1.06 to 1.26). In an exploratory analysis of the combined regimens, among the patients with T1, T2, or T3 and N1 cancers, 3 months of therapy was noninferior to 6 months, with a 3-year rate of disease-free survival of 83.1% and 83.3%, respectively (hazard ratio, 1.01; 95% CI, 0.90 to 1.12). Among patients with cancers that were classified as T4, N2, or both, the disease-free survival rate for a 6-month duration of therapy was superior to that for a 3-month duration (64.4% vs. 62.7%) for the combined treatments (hazard ratio, 1.12; 95% CI, 1.03 to 1.23; P=0.01 for superiority).

CONCLUSIONS

Among patients with stage III colon cancer receiving adjuvant therapy with FOLFOX or CAPOX, noninferiority of 3 months of therapy, as compared with 6 months, was not confirmed in the overall population. However, in patients treated with CAPOX, 3 months of therapy was as effective as 6 months, particularly in the lower-risk subgroup. (Funded by the National Cancer Institute and others.).

Regorafenib dose optimization study (ReDOS): Randomized phase II trial to evaluate dosing strategies for regorafenib in refractory metastatic colorectal cancer (mCRC)–An ACCRU Network study

611

Background: Regorafenib is an oral multikinase inhibitor with survival benefit in refractory mCRC patients (pts). Toxicities such as Palmar-plantar erythrodysesthesia syndrome (PPES), fatigue and hypertension (HTN) have limited its use. Despite absence of supportive data, various dosing or interval scheduling have been implemented into clinical practice. Methods: A randomized phase II study of regorafenib dose-escalation (Arm A: 80 mg/day, weekly dose escalation if no significant drug-related toxicities, up to 160 mg/day) vs. standard dose (Arm B: 160 mg/day) in pts with mCRC for 21 days of a 28-day cycle. Pts were randomized 1:1:1:1 to arms A1 and B1 (Pre-emptive Clobetasol for PPES); A2 and B2 (Reactive Clobetasol). The primary endpoint was the proportion of patients who completed 2 cycles of treatment and initiated the 3rd in Arm A (Pooled A1 + A2) vs. Arm B (Pooled B1 + B2). Superiority for Arm A was to be declared if the one-sided p-value calculated using Fisher’s exact method was less than 0.2. Results: From June 2015 to June 2017, 123 pts were randomized with 116 (A = 54, B = 62) evaluable for the primary endpoint. Demographic data were well balanced with overall median age of 61yrs (range: 29-81), M/F (61/39%) and ECOG PS 0/1 (37/63%) and KRAS MT/WT/UNK (47/44/9%).The study met its primary endpoint with 43% of pts on Arm A initiating the 3rd vs. only 25% of pts Arm B [one-sided p-value 0.028]. Median Overall Survival (OS) was improved in Arm A vs. Arm B (9.0 mos vs. 5.9 mos; p = 0.094). Median Progression Free Survival (PFS) was 2.5 mos for Arm A vs. 2.0 mos for Arm B (p=0.553). Overall rates of grade 3/4 toxicity were more favorable for Arm A vs. Arm B (% PPES 15 vs. 16, HTN 7 vs. 15 and fatigue 13 vs. 18, respectively). Multiple QOL parameters were improved in A vs. B primarily at week 2 of the first cycle. Conclusion: A strategy with weekly dose escalation of regorafenib from 80 mg to 160 mg/day was found to be superior to a starting dose of 160 mg/day. These results establish a new standard for optimizing regorafenib dosing. Further data on outcomes of preemptive vs. reactive clobetasol strategies are undergoing analysis and will be presented later. Clinical trial information: NCT02368886.

Associations of incidence of common adverse events (AEs) and survival outcomes in metastatic colorectal cancer (mCRC) patients (pts) treated with first line chemotherapy: Findings from 9,812 pts in the ARCAD database

617

Background: There is limited, often conflicting evidence about AE timing, severity or associations with outcomes with the use of cytotoxic agents in cancer treatment. We investigated the impact on overall survival (OS) and progression-free survival (PFS) of selected common AEs (neutropenia, diarrhea, nausea, vomiting, neuropathy) occurring in patients receiving first line oxaliplatin (Oxa)- and/or irinotecan(Iri)-based regimens for mCRC. Methods: The CTCAE grading scores of at least one AE of interest were available on 9812 pts treated with chemotherapy alone (median age 63; 62.4% male, 50.1% ECOG PS 0) from 17 1st-line randomized trials. Patients who also received biologics were excluded in the primary analyses. AEs occurring during the first 6 weeks of treatment and entire treatment were analyzed by stratified multivariable Cox models in relationship to OS/PFS. 55.7% pts received Oxa- regimens, 35.7% Iri-regimens, and 8.6% combined Oxa- and Iri-regimens. Results: Within the first 6 weeks of treatment, G3+ neutropenia (HRadj= 1.3, 95% CI, 1.06-1.59, padj 0.01), diarrhea (HRadj= 1.48, 95% CI, 1.23-1.79, padj < .0001), nausea (HRadj= 1.53, 95% CI, 1.17-1.99, padj 0.002) and vomiting (HRadj= 1.56, 95% CI, 1.18-2.07, padj 0.002) were associated with significantly worse OS for Iri-regimens, but only G3+ nausea predicted for worse OS for Oxa- regimens (HRadj= 1.61, 95% CI, 1.18-2.21, padj 0.003). For AEs experienced at any time, G3+ neutropenia and neuropathy were significantly associated with longer PFS and OS for Oxa-regimens, while G3+ vomiting and nausea were associated with worse OS for both Oxa- and Iri-based regimens. Sensitivity analysis showed largely concordant results by including pts who also received biologics. Conclusions: The association between more severe selected AEs and outcome varies between AEs and is influenced by timing of the occurrence. More severe selected AEs occurring early in treatment are associated with worse outcomes. In contrast, for AEs occurring at any time, G3+ neutropenia and neuropathy predicted for longer PFS and/or OS in Oxa-treated pts.

Impact of overall severity of adverse events (AEs) on long-term outcomes in metastatic colorectal cancer (mCRC) patients (pts) treated with first line systemic chemotherapy: Findings from 3,971 pts in the ARCAD database

3582

Background: The prognostic importance of the incidence, severity, type and duration of AEs pts experience during chemotherapy varies between tumor types, and the available evidence across the board is often conflicting. Here we investigated the impact of the overall severity of AEs among pts with mCRC receiving first-line oxaliplatin (Oxa)- and/or irinotecan(Iri)-based regimens. Methods: The overall severity of AE data (i.e., max grade (G) of all AEs) were available on 3,971 pts (median age 61; 60% male, 47% ECOG PS 1+; 57% 2+ metastatic sites) enrolled onto 6 1st-line randomized trials. Around 46%, 45%, and 9% of pts had received Oxa-, Iri-, and Oxa+Iri-based regimens, respectively. Pts receiving biologic agents were excluded. Stratified multivariate Cox models were used to assess the associations with overall survival (OS) and progression-free survival (PFS); adjusted hazard ratios (HRadj) and 95% confidence intervals (CIs) are reported. Results: Pts who only received Oxa-based treatment reported the lowest rate of G3+ AEs (p < .0001) compared to pts treated with Iri- or Oxa+Iri-based regimens. Older age, female gender, and PS 1 or 2+ were associated with higher grade AEs (all p < .0001). Considering AEs experienced within 6w after randomization, 10% and 61% of pts experienced G4+ and G2-3 AEs, respectively. G3+ AEs were associated with a shorter OS for both pts receiving Oxa- (HRadj= 1.2, 95% CI, 1.1-1.3, padj < .0001) and Iri-based regimens (HRadj= 1.4, 95% CI, 1.2-1.5, padj < .0001). For the entire treatment course, 19% and 72% of pts experienced G4+ and G2-3 AEs, respectively. For Oxa-based regimens, pts with G3+ AEs had a longer OS (HRadj= 0.86, 95% CI, 0.78-0.94, padj = .0016), whereas G3+ AEs were associated with a shorter OS (HRadj= 1.2, 95% CI, 1.1-1.4, padj = .0004) for pts treated with Iri-based regimens. Similar patterns were seen for PFS. Conclusions: Pts who reported higher grade AEs during initial treatment (≤6w) have significantly worse outcome than those who do not. Further analyses with treatment exposure/detailed dose-AE profile and its impact on survival are warranted.

North Central Cancer Treatment Group N0543 (Alliance): A phase 2 trial of pharmacogenetic-based dosing of irinotecan, oxaliplatin, and capecitabine as first-line therapy for patients with advanced small bowel adenocarcinoma

BACKGROUND

Oxaliplatin in combination with either 5-fluorouracil or capecitabine is commonly used as first-line therapy for patients with small bowel adenocarcinoma. The addition of irinotecan improves survival in other gastrointestinal tumors but at the cost of hematologic toxicity. The authors performed a phase 2 cooperative group study (North Central Cancer Treatment Group N0543, Alliance) using genotype-dosed capecitabine, irinotecan, and oxaliplatin (gCAPIRINOX), with dosing assigned based on UDP glucuronosyltransferase family 1 member A1 (UGT1A1) genotype to test: 1) whether the addition of irinotecan would improve outcomes; and 2) whether UGT1A1 genotype-based dosing could optimize tolerability.

METHODS

Previously untreated patients with advanced small bowel adenocarcinoma received irinotecan (day 1), oxaliplatin (day 1), and capecitabine (days 2-15) in a 21-day cycle and were dosed with gCAPIRINOX according to UGT1A1*28 genotypes (6/6, 6/7, and 7/7).

RESULTS

A total of 33 patients (17 with the 6/6 genotype, 10 with the 6/7 genotype, and 6 with the 7/7 genotype) were enrolled from October 2007 to November 2013; 73% were male, with a mean age of 64 years (range, 41-77 years). Location of the primary tumor included the duodenum (58%), jejunum (30%), and ileum (9%). The regimen yielded a confirmed response rate of 37.5% (95% confidence interval, 21%-56%), with a median progression-free survival of 8.9 months and a median overall survival of 13.4 months. Neither hematologic toxicity (grade ≥3 in 52.9%, 30.0%, and 33.3%, respectively, of the 6/6, 6/7, and 7/7 genotype groups) nor tumor response rate (41.2%, 33%, and 33%, respectively) were found to differ significantly by UGT1A1 genotype.

CONCLUSIONS

UGT1A1 genotype-directed dosing (gCAPIRINOX) appears to be feasible with favorable rates of hematologic toxicity compared with prior 3-drug studies in unselected patients. Larger studies would be needed to determine the regimen's comparability to oxaliplatin and capecitabine (CapeOx) alone or if response/toxicity differs among patients with different UGT1A1 genotypes. Cancer 2017;123:3494-501. © 2017 American Cancer Society.

Association of DNA Mismatch Repair and Mutations in BRAF and KRAS With Survival After Recurrence in Stage III Colon Cancers : A Secondary Analysis of 2 Randomized Clinical Trials

Importance

The association of biomarkers with patient survival after recurrence (SAR) of cancer is poorly understood but may guide management and treatment.

Objective

To determine the association of DNA mismatch repair (MMR) status and somatic mutation in the B-Raf proto-oncogene (c.1799T>A [V600E]; BRAFV600E) or exon 2 of the KRAS proto-oncogene (KRAS) in the primary tumor with SAR in patients with stage III colon carcinomas treated with adjuvant chemotherapy.

Design, Setting, and Participants

Patients with resected stage III colon cancers were randomized to adjuvant FOLFOX (folinic acid [leucovorin calcium], fluorouracil, and oxaliplatin) chemotherapy with or without cetuximab (North Central Cancer Treatment Group N0147 trial) or adjuvant FOLFOX chemotherapy with or without bevacizumab (National Surgical Adjuvant Breast and Bowel Project C-08 trial). Associations of biomarkers with SAR were analyzed using Cox proportional hazards models adjusted for clinicopathologic features and time to recurrence (data collected February 10, 2004, to August 7, 2015).

Main Outcomes and Measures

The primary study outcome was survival after recurrence of cancer. A secondary outcome measure was the effect of the site of the primary tumor on the association of biomarkers with SAR.

Results

Among 871 patients with cancer recurrence in the N0147 trial (472 men [54.2%] and 399 women [45.8%]; mean [SD] age, 57.8 [11.2] years) and 524 in the C-08 trial (269 men [51.3%] and 255 women [48.7%]; mean [SD] age, 57.0 [11.7] years), multivariable analysis revealed that patients whose tumors had deficient vs proficient MMR had significantly better SAR (adjusted hazard ratio [AHR], 0.70; 95% CI, 0.52-0.96; P = .03). Patients whose tumors harbored mutant BRAFV600E (AHR, 2.45; 95% CI, 1.85-3.25; P < .001) or mutant KRAS (AHR, 1.21; 95% CI, 1.00-1.47; P = .052) had worse SAR compared with those whose tumors had wild-type copies of both genes, although only results for BRAFV600E achieved statistical significance. Significant interactions were found for MMR (P = .03) and KRAS (P = .02) by primary tumor site for SAR. Improved SAR was observed for patients with deficient MMR tumors of the proximal vs distal colon (AHR, 0.57; 95% CI, 0.40-0.83; P = .003), and worse SAR was observed for tumors of the distal colon with mutant KRAS in codon 12 (AHR, 1.76; 95% CI, 1.30-2.38; P < .001) and codon 13 (AHR, 1.76; 95% CI, 1.08-2.86; P = .02).

Conclusions and Relevance

In patients with recurrence of stage III colon cancer, deficient MMR was significantly associated with better SAR, and this benefit was limited to primary tumors of the proximal colon. Mutations in BRAFV600E were significantly associated with worse SAR, and worse SAR for BRAFV600E or KRAS mutant tumors was more strongly associated with distal cancers. These biomarkers have implications for patient management at recurrence.

Trial Registration

clinicaltrials.gov Identifiers: NCT00079274 and NCT00096278.

Prognosis of patients with peritoneal metastatic colorectal cancer given systemic therapy: an analysis of individual patient data from prospective randomised trials from the Analysis and Research in Cancers of the Digestive System (ARCAD) database

BACKGROUND

Patients with peritoneal metastatic colorectal cancer have reduced overall survival compared with patients with metastatic colorectal cancer without peritoneal involvement. Here we further investigated the effect of the number and location of metastases in patients receiving first-line systemic chemotherapy.

METHODS

We analysed individual patient data for previously untreated patients enrolled in 14 phase 3 randomised trials done between 1997 and 2008. Trials were included if protocols explicitly pre-specified and solicited for patients with peritoneal involvement in the trial data collection process or had done a formal peritoneum-focused review of individual pre-treatment scans. We used stratified multivariable Cox models to assess the prognostic associations of peritoneal metastatic colorectal cancer with overall survival and progression-free survival, adjusting for other key clinical-pathological factors (age, sex, Eastern Cooperative Oncology Group (ECOG) performance score, primary tumour location [colon vs rectum], previous treatment, and baseline BMI). The primary endpoint was difference in overall survival between populations with and without peritoneal metastases.

FINDINGS

Individual patient data were available for 10 553 patients. 9178 (87%) of 10 553 patients had non-peritoneal metastatic colorectal cancer (4385 with one site of metastasis, 4793 with two or more sites of metastasis), 194 (2%) patients had isolated peritoneal metastatic colorectal cancer, and 1181 (11%) had peritoneal metastatic colorectal cancer and other organ involvement. These groups were similar in age, ethnic origin, and use of targeted treatment. Patients with peritoneal metastatic colorectal cancer were more likely than those with non-peritoneal metastatic colorectal cancer to be women (565 [41%] of 1371 vs 3312 [36%] of 9169 patients; p=0·0003), have colon primary tumours (1116 [84%] of 1334 patients vs 5603 [66%]; p<0·0001), and have performance status of 2 (136 [10%] vs 521 [6%]; p<0·0001). We recorded a higher proportion of patients with mutated BRAF in patients with peritoneal-only (eight [18%] of 44 patients with available data) and peritoneal metastatic colorectal cancer with other sites of metastasis (34 [12%] of 289), compared with patients with non-peritoneal metastatic colorectal cancer (194 [9%] of 2230; p=0·028 comparing the three groups). Overall survival (adjusted HR 0·75, 95% CI 0·63-0·91; p=0·003) was better in patients with isolated non-peritoneal sites than in those with isolated peritoneal metastatic colorectal cancer. Overall survival of patients with two of more non-peritoneal sites of metastasis (adjusted HR 1·04, 95% CI 0·86-1·25, p=0.69) and those with peritoneal metastatic colorectal cancer plus one other site of metastasis (adjusted HR 1·10, 95% CI 0·89-1·37, p=0·37) was similar to those with isolated peritoneal metastases. Compared with patients with isolated peritoneal metastases, those with peritoneal metastases and two or more additional sites of metastasis had the shortest survival (adjusted HR 1·40; CI 1·14-1·71; p=0·0011).

INTERPRETATION

Patients with peritoneal metastatic colorectal cancer have significantly shorter overall survival than those with other isolated sites of metastases. In patients with several sites of metastasis, poor survival is a function of both increased number of metastatic sites and peritoneal involvement. The pattern of metastasis and in particular, peritoneal involvement, results in prognostic heterogeneity of metastatic colorectal cancer.

FUNDING

None.

Prognostic value of isolated peritoneal versus other metastatic sites in colorectal cancer (CRC) patients treated by systemic chemotherapy: Findings from 9,265 pts in the ARCAD database

656

Background: Patients (pts) with peritoneal metastases from CRC (pmCRC) have reduced OS compared to mCRC pts without peritoneal involvement. Here we further investigated the impact of number and location of metastases among pts receiving first-line systemic chemotherapy. Methods: Individual patient data were available on 9,265 pts (median age 64; 63% male; 93% ECOG PS 0-1; 68% colon primary tumor; brain metastases excluded) enrolled onto 12 first-line randomized trials (4 tested targeted regimens). Stratified multivariable Cox models were used to assess the associations with overall survival (OS); adjusted hazard ratios (HRadj) and 95% confidence intervals are reported (CI). Results: There were 7,963 (86%) pts with non-pmCRC (3,904 with one disease site; 4,059 with ≥2 disease sites), 191 (2%) pts with isolated pmCRC, and 1,111 (12%) non-isolated pmCRC. These groups were similar in age, race, and use of targeted chemotherapy. Compared to non-pmCRC, pts with pmCRC were more likely to be female (41% vs. 36%, p<.001), have colon primary tumors (85% vs. 67%, p<.0001), and have PS2 (10% vs. 6%, p<.0001). Compared to isolated pmCRC, pts with solitary non-peritoneal sites (both M1a) had significantly better OS (HRadj=0.78; CI, 0.64-0.94, p=.009) while pts with ≥2 non-peritoneal sites had similar OS (HRadj=1.06; CI 0.88-1.28, p=.535). OS of pts with pmCRC with a single other disease site (n=446) was similar to isolated pmCRC (HRadj=1.13; CI 0.91-1.40, p=.28), but those with pmCRC + ≥2 additional disease sites (n=665) had shortest survival (HRadj=1.44; CI 1.17-1.77, p<.001). A combination of peritoneal and liver metastases (n=821; HRadj=1.37, CI 1.12-1.67, p=.002) was associated with poorer survival compared with isolated pmCRC; but combination with extrahepatic sites (n=290; HRadj=1.15, CI 0.91-1.45, p=.25) was not. Conclusions: pmCRC pts have significantly worse survival than those with other solitary site mCRC. Among those with multiple disease sites, poorer survival is a function of increased number of metastatic sites and peritoneal involvement, which indicates prognostic heterogeneities among M1b pts.

Gene expression profiling identifies responsive patients with cancer of unknown primary treated with carboplatin, paclitaxel, and everolimus: NCCTG N0871 (alliance)

BACKGROUND

Carboplatin (C) and paclitaxel (P) are standard treatments for carcinoma of unknown primary (CUP). Everolimus, an mTOR inhibitor, exhibits activity in diverse cancer types. We did a phase II trial combining everolimus with CP for CUP. We also evaluated whether a gene expression profiling (GEP) test that predicts tissue of origin (TOO) could identify responsive patients.

PATIENTS AND METHODS

A tumor biopsy was required for central confirmation of CUP and GEP. Patients with metastatic, untreated CUP received everolimus (30 mg weekly) with P (200 mg/m(2)) and C (area under the curve 6) every 3 weeks. The primary end point was response rate (RR), with 22% needed for success. The GEP test categorized patients into two groups: those having a TOO where CP is versus is not considered standard therapy.

RESULTS

Of 45 assessable patients, the RR was 36% (95% confidence interval 22% to 51%), which met criteria for success. Grade ≥3 toxicities were predominantly hematologic (80%). Adequate tissue for GEP was available in 38 patients and predicted 10 different TOOs. Patients with a TOO where platinum/taxane is a standard (n = 19) tended to have higher RR (53% versus 26%) and significantly longer PFS (6.4 versus 3.5 months) and OS (17.8 versus 8.3 months, P = 0.005), compared with patients (n = 19) with a TOO where platinum/taxane is not standard.

CONCLUSIONS

Everolimus combined with CP demonstrated promising antitumor activity and an acceptable side-effect profile. A tumor biomarker identifying TOO may be useful to select CUP patients for specific antitumor regimens.

CLINICALTRIALSGOV

NCT00936702.

Clinical Utility of Metrics Based on Tumor Measurements in Phase II Trials to Predict Overall Survival Outcomes in Phase III Trials by Using Resampling Methods

PURPOSE

Phase II clinical trials inform go/no-go decisions for proceeding to phase III trials, and appropriate end points in phase II trials are critical for facilitating this decision. Phase II solid tumor trials have traditionally used end points such as tumor response defined by Response Evaluation Criteria for Solid Tumors (RECIST). We previously reported that absolute and relative changes in tumor measurements demonstrated potential, but not convincing, improvement over RECIST to predict overall survival (OS). We have evaluated the metrics by using additional measures of clinical utility and data from phase III trials.

METHODS

Resampling methods were used to assess the clinical utility of metrics to predict phase III outcomes from simulated phase II trials. In all, 2,000 phase II trials were simulated from four actual phase III trials (two positive for OS and two negative for OS). Cox models for three metrics landmarked at 12 weeks and adjusted for baseline tumor burden were fit for each phase II trial: absolute changes, relative changes, and RECIST. Clinical utility was assessed by positive predictive value and negative predictive value, that is, the probability of a positive or negative phase II trial predicting an effective or ineffective phase III conclusion, by prediction error, and by concordance index (c-index).

RESULTS

Absolute and relative change metrics had higher positive predictive value and negative predictive value than RECIST in five of six treatment comparisons and lower prediction error curves in all six. However, differences were negligible. No statistically significant difference in c-index across metrics was found.

CONCLUSION

The absolute and relative change metrics are not meaningfully better than RECIST in predicting OS.

Association of age with survival in patients with metastatic colorectal cancer: analysis from the ARCAD Clinical Trials Program

PURPOSE

This study addressed whether age is prognostic for overall survival (OS) or progression-free survival (PFS) in patients with metastatic colorectal cancer (mCRC).

PATIENTS AND METHODS

A total of 20,023 patients from 24 first-line clinical trials in the ARCAD (Aide et Recherche en Cancérologie Digestive) database were analyzed. Primary age effects and interactions with age,sex, performance status (PS), and metastatic site were modeled using Cox proportional hazards stratified by treatment arm within study.

RESULTS

Of total patients, 3,051 (15%) were age < or =50 years. Age was prognostic for both OS (P < .001)and PFS (P < .001), with U-shaped risk (i.e., highest risk was evident in youngest and oldest patients). Relative to patients of middle age, the youngest patients experienced 19% (95% CI, 7% to 33%) increased risk of death and 22% (95% CI, 10% to 35%) increased risk of progression. The oldest patients experienced 42% (95% CI, 31% to 54%) increased risk of death and 15% (95% CI, 7% to 24%) increased risk of progression or death. This relationship was more pronounced in the first year of follow-up. Age remained marginally significant for OS (P = .08) when adjusted forPS, sex, and presence of liver, lung, or peritoneal metastases, and age was significant in an adjusted model for PFS (P = .005). The age effect did not differ by site of metastatic disease, year of enrollment, type of therapy received, or biomarker mutational status.

CONCLUSION

Younger and older age are associated with poorer OS and PFS among treated patients with mCRC. Younger and older patients may represent higher-risk populations, and additional studies are warranted.

Nomograms for overall survival (OS) and progression-free survival (PFS) in metastatic colorectal cancer (mCRC): Construction from 19,678 ARCAD patients

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Background: Prospective survival prediction of patients with metastatic colorectal cancer is difficult. Prognosis estimation based on readily available clinicopathologic factors has the potential to inform clinical practice and improve risk stratification for clinical trials. We constructed prognostic nomograms for OS and PFS in mCRC using the multi-trial ARCAD database. Methods: Data from 19,678 mCRC pts accrued to 24 first line randomized phase III clinical trials since 1997 were used to construct and validate Cox models for PFS and OS, stratified by treatment arm within each study. Candidate variables included age, gender, BMI, performance status, colon vs. rectal cancer, prior chemotherapy, number of metastatic sites, sites of metastases (liver, lung, lymph nodes), and baseline bilirubin, albumin, white blood cell count, hemoglobin, platelets, absolute neutrophil count, and derived neutrophil:lymphocyte ratio (dNLR). Missing data (<11%) were imputed, continuous variables modeled with splines, and clinically relevant pairwise interactions considered if p<0.001. Final models were internally validated via bootstrapping to obtain optimism-corrected calibration and discrimination C-indices, and externally validated using a 10% holdout sample from each trial. Results: Nomograms for OS and PFS including remaining variables were well calibrated with C-indices of 0.66 and 0.60, respectively. Evaluation of external validity revealed good concordance; 71% and 67% respectively between predicted (> vs. <50% probability) and actual (yes/no) 1-year OS and 6-month PFS, and median 1-year OS and 6-month PFS predictions fell within the actual 95% Kaplan-Meier intervals. Gender, liver and lung metastases, and dNLR were not prognostic for OS; prior chemo, colon vs. rectum, dNLR, liver and lymph node metastases, and gender did not predict for PFS. No clinically relevant pairwise interactions were identified. Conclusions: The proposed nomograms are well calibrated and internally and externally valid. These tools have the potential to aid prognostication and patient/physician communication, and balance risk in randomized trials in mCRC.

Prophylactic cranial irradiation in elderly patients with small cell lung cancer: findings from a North Central Cancer Treatment Group pooled analysis

OBJECTIVES

To examine the efficacy of prophylactic cranial irradiation (PCI) in elderly patients with small cell lung cancer (SCLC) (≥70 years of age) from a pooled analysis of four prospective trials.

MATERIALS & METHODS

One hundred fifty-five patients with SCLC (limited stage, LSCLC, and extensive stage, ESCLC) participated in four phase II or III trials. Ninety-one patients received PCI (30 Gy/15 or 25 Gy/10) and 64 patients did not receive PCI. Survival was compared in a landmark analysis that included only patients who had stable disease or better in response to primary therapy.

RESULTS

Patients who received PCI had better survival than patients who did not receive PCI (median survival 12.0 months vs. 7.6 months, 3-year overall survival 13.2% vs. 3.1%, HR = 0.53 [95% CI 0.36-0.78], p = 0.001). On multivariate analysis of the entire cohort, the only factor that remained significant for survival was stage (ESCLC vs. LSCLC, p = 0.0072). In contrast, the multivariate analysis of patients who had ESCLC revealed that PCI was the sole factor associated with a survival advantage (HR = 0.47 [95% CI 0.24-0.93], p = 0.03). Grade 3 or higher adverse events (AEs) were significantly greater in patients who received PCI (71.4% vs. 47.5%, p = 0.0031), with non-neuro and non-heme being the specific AE categories most strongly correlated with PCI delivery.

CONCLUSIONS

PCI was associated with a significant improvement in survival for our entire elderly SCLC patient cohort on univariate analysis. Multivariate analysis suggested that the survival advantage remained significant in patients with ESCLC. PCI was also associated with a modest increase in grade 3 or higher AEs.

Oral cancer chemotherapy adherence and adherence assessment tools: a report from North Central Cancer Group Trial N0747 and a systematic review of the literature

Oncologists are now prescribing more oral chemotherapy than ever before, thus placing the onus for taking the right dose at the right time under the right circumstances directly on the patient. This study was undertaken to understand emerging adherence issues and to explore available adherence assessment tools. This two-part study (1) examined N0747, a randomized phase II trial that tested the oral agents, sunitinib and capecitabine, in patients with metastatic esophageal cancer from an adherence standpoint, and (2) conducted a systematic review to compile and assess adherence tools that can be used in future clinical trials. First, in N0747, patients were assigned to sunitinib and capecitabine versus capecitabine; 53 chemotherapy cycles were prescribed to this 12-patient cohort. Nearly all patients denoted that they "always or almost always" took their pills as prescribed, and two patients who reported lack of full adherence suffered from grade 3+ adverse events. Surprisingly, however, over 14 cycles, 9 patients reported grade 3+ toxicity but checked "always or almost always" to describe their adherence. No relationships were observed between adherence and cancer outcomes. Secondly, 21 articles identified the following adherence tools: (1) healthcare providers' interviews, (2) patient-reported adherence with diaries/calendars, (3) patient-completed adherence scales, (4) medication event monitoring, (5) automated voice response, (6) drug/metabolite assays, and (7) prescription databases. Of note, only the automated voice response seems capable of real-time detection of over-adherence, as observed in N0747. Oral chemotherapy adherence should be further studied, particularly from the standpoint of over-adherence.

Prognostic value of early objective tumor response (EOTR) to first-line systemic therapy in metastatic colorectal cancer (mCRC): Individual patient data (IPD) meta-analysis of randomized trials from the ARCAD database

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Background: EOTR has been suggested as a potential surrogate for overall survival (OS) in patients (pts) with mCRC and allows early assessment of treatment efficacy, facilitating adaptive trial design. We assessed at the individual patient level, the correlation between EOTR (complete or partial response) at 6, 8 and 12 weeks (wk), OS and progression free survival (PFS) in pts with mCRC treated with 1stline chemotherapy with or without a targeted agent as a first step in a surrogacy demonstration. Methods: IPD from 13,949 pts enrolled on 15 randomized Phase III trials in 1st line mCRC were used; 8 trials included targeted (anti-angiogenic and anti-EGFR) agents. EOTR prognostic value was assessed by landmark analyses using Cox models stratified by treatment assignment. P-values <0.01 were considered statistically significant to account for multiple comparisons. Results: Of 13,949 pts, 11,987 had sufficient response data to be included in the analysis. Median OS was 21.7 months (mo) in pts with an EOTR vs. 16.5 mo without EOTR at 6 wk (p<.0001, Hazard Ratio [HR] 0.64, 95% confidence interval [CI] 0.58-0.70, c statistic [c] 0.55). HRs were similar whether pts were treated with targeted therapies (p<.0001, HR 0.68, 95% CI 0.58-0.80, x 0.54) or non-targeted therapies (p<.0001, HR 0.61, 95% CI 0.55-0.69, x 0.55). Median PFS was 8.4 mo in pts with EOTR at 6 wk vs. 7.0 mo in pts without EOTR (p<.0001, HR 0.79, 95% CI 0.73-0.85). EOTR at 8 and 12 wks were also significantly associated with longer OS and PFS. The prognostic value of EOTR at 6, 8 and 12 wks remained significant (p<0.0001) after adjusting for age, gender, performance statusand location of metastatic disease (lung or liver). Overall tumor response (to 26 wk) however provided superior OS prediction (p<.0001, HR 0.51, 95% CI, 0.47-0.56, CS 0.61) vs. EOTR. Conclusions: Early response measured at 6, 8 or 12 wk after starting 1st line treatment was a strong and independent predictor of both OS and PFS in patient with mCRC and warrants further consideration as a potential endpoint for future trials, particularly randomized phase II trials.

A randomized phase II study of gemcitabine and carboplatin with or without cediranib as first-line therapy in advanced non-small-cell lung cancer: North Central Cancer Treatment Group Study N0528

INTRODUCTION

The purpose of this study was to assess the safety and efficacy of gemcitabine and carboplatin with (arm A) or without (arm B) daily oral cediranib as first-line therapy for advanced non-small-cell lung cancer.

METHODS

A lead-in phase to determine the tolerability of gemcitabine 1000 mg/m on days 1 and 8, and carboplatin on day 1 at area under curve 5 administered every 21 days with cediranib 45 mg once daily was followed by a 2 (A):1 (B) randomized phase II study. The primary end point was confirmed overall response rate (ORR) with 6-month progression-free survival (PFS6) rate in arm A as secondary end point. Polymorphisms in genes encoding cediranib targets and transport were correlated with treatment outcome.

RESULTS

On the basis of the safety assessment, cediranib 30 mg daily was used in the phase II portion. A total of 58 and 29 evaluable patients were accrued to arms A and B. Patients in A experienced more grade 3+ nonhematologic adverse events, 71% versus 45% (p = 0.01). The ORR was 19% (A) versus 20% (B) (p = 1.0). PFS6 in A was 48% (95% confidence interval: 35%-62%), thus meeting the protocol-specified threshold of at least 40%. The median overall survival was 12.0 versus 9.9 months (p = 0.10). FGFR1 rs7012413, FGFR2 rs2912791, and VEGFR3 rs11748431 polymorphisms were significantly associated with decreased overall survival (hazard ratio 2.78-5.01, p = 0.0002-0.0095).

CONCLUSIONS

The trial did not meet its primary end point of ORR but met its secondary end point of PFS6. The combination with cediranib 30 mg daily resulted in increased toxicity. Pharmacogenetic analysis revealed an association of FGFR and VEGFR variants with survival.

Prophylactic cranial irradiation in small-cell lung cancer: findings from a North Central Cancer Treatment Group Pooled Analysis

BACKGROUND

This pooled analysis evaluated the outcomes of prophylactic cranial irradiation (PCI) in 739 small-cell lung cancer (SCLC patients with stable disease (SD) or better following chemotherapy ± thoracic radiation therapy (TRT) to examine the potential advantage of PCI in a wider spectrum of patients than generally participate in PCI trials.

PATIENTS AND METHODS

Three hundred eighteen patients with extensive SCLC (ESCLC) and 421 patients with limited SCLC (LSCLC) participated in four phase II or III trials. Four hundred fifty-nine patients received PCI (30 Gy/15 or 25 Gy/10) and 280 did not. Survival and adverse events (AEs) were compared.

RESULTS

PCI patients survived significantly longer than non-PCI patients {hazard ratio [HR] = 0.61 [95% confidence interval (CI): 0.52-0.72]; P < 0.0001}. The 1- and 3-year survival rates were 56% and 18% for PCI patients versus 32% and 5% for non-PCI patients. PCI was still significant after adjusting for age, performance status, gender, stage, complete response, and number of metastatic sites (HR = 0.82, P = 0.04). PCI patients had significantly more grade 3+ AEs (64%) compared with non-PCI patients (50%) (P = 0.0004). AEs associated with PCI included alopecia and lethargy. Dose fractionation could be compared only for LSCLC patients and 25 Gy/10 was associated with significantly better survival compared with 30 Gy/15 (HR = 0.67, P = 0.018).

CONCLUSIONS

PCI was associated with a significant survival benefit for both ESCLC and LSCLC patients who had SD or a better response to chemotherapy ± TRT. Dose fractionation appears important. PCI was associated with an increase in overall and specific grade 3+ AE rates.

N0821: A phase II first-line study of a combination of pemetrexed (P), carboplatin (C), and bevacizumab (B) in elderly patients with good performance status (PS < 2)

7555

Background: In a retrospective exploratory analysis of E4599, patients (pts) > 70 yo had a higher frequency of and more severe toxicities without apparent survival benefit from the addition of B to C+paclitaxel. We hypothesized that in this pt population, B will have better safety and efficacy profile when used in combination with C+P. Methods: Pts >/= 70 yo with previously untreated stage IIIB/IV (TNM 6th ed) nonsquamous NSCLC, ECOG PS 0-1, measurable disease and adequate organ function were eligible. C at AUC 6, P at 500 mg/m2 and B at 15 mg/kg were administered on day 1 of each 21-day cycle for up to 6 cycles followed by maintenance P+B in patients with CR, PR or SD. The primary endpoint was 6-month progression-free survival (PFS) rate. The treatment would be considered promising based on a single arm one-stage binomial design if 34 or more successes out of 55 patients were observed. This design had an exact significance level of 0.05 at 93% power to detect a true success rate of at least 70%. Polymorphisms in VEGFA, FPGS, GGH, SLC19A1 and TYMS in germline DNA were correlated with treatment outcome. Results: 58 eligible pts were enrolled; 29 males/29 females. Median age was 75. Median treatment cycles received was 6. Grade 3 or higher adverse events (AE) were reported in 49 (85%) pts. There were no treatment-related deaths. The most common grade 3/4 AEs(regardless of attribution) were hypertension (10%), fatigue (28%), dehydration (9%), neutropenia (43%) and thrombocytopenia (21%). There were 3 (5%) grade 3/4 hemorrhagic events. 8 (14%) had grade 4 neutropenia and 3 (5%) had grade 4 thrombocytopenia. Grade 3/4 ischemic/thromboembolic events occurred in 6 pts (10%). Thirty-four out of the first 54 (63%, 95% CI: 48.7-75.7%) evaluable pts met the primary endpoint (4 pts were lost to follow-up prior to 6 months). The confirmed ORR was 37.9% (95% CI: 25.5-51.6%). Median time to treatment failure was 4.8 months (95% CI: 3.9-6.4). Median PFS was 7.1 months (95% CI: 5.9-11.7), median OS was 13.7 months (95% CI: 9.4-15.7). Results of SNP analysis will be presented. Conclusions: C+P+B followed by maintenance P+B is an active and tolerable first-line regimen for elderly patients with good PS.

Histological healing following surgical endodontics and its implications in case assessment: a case report

Following extraction of a symptomatic mandibular premolar which had been subjected to two periradicular surgical procedures, significant apical healing was identified histologically. The implications of these findings are discussed in relation to contemporary advocated treatment regimens, case assessment, and interpretation for success and failure.