Citations

4020 Background: Adjuvant chemotherapy (AC) presents a substantial patient education challenge to medical oncologists (MOs). Findings from our 2005 pilot survey suggest that a significant fraction of colorectal cancer (CRC) survivors are willing to undergo AC for modest treatment benefits, but their understanding of risks and benefits may be suboptimal. This project attempted to validate these findings by surveying patients with CRC (Pts) who previously received AC. Methods: 150 Pts who received AC for CRC in the last 5 years were recruited to listen to an audio program on AC featuring interviews with clinical investigators (CIs) and Pts who received AC. Based on this input, Pts were asked whether they would undergo the same AC again for varying absolute treatment benefits. A corresponding survey asked 24 CRC CIs and 150 MOs to predict how patients would respond. The survey also queried Pts about their expectations of and experiences with AC side effects. Results: About 1/3 of Pts would be treated again with AC for a 1% absolute reduction in recurrence risk (ARRR), and about 2/3 believed a 5% ARRR would justify treatment. There were no statistically significant differences between responses of males and females or between Pts receiving oxaliplatin (OX) and those receiving other regimens. ( Table 1 ) The corresponding estimates of CIs and MOs were lower. Additionally, AC side effects were different than expected: 57% and 66% of Pts experienced less GI toxicity and alopecia, respectively, while 38% and 46% of Pts receiving OX experienced greater cold intolerance and numbness. Conclusions: Many potential obstacles exist in communicating with Pts about AC including heterogeneity in Pts’ attitudes towards risk/benefit trade-offs and preconceptions about treatment side effects. The next step in this initiative will be to examine these issues prospectively by evaluating the impact of an audio/web education supplement on the decision-making process. [Table: see text] No significant financial relationships to disclose.

11586 Background: Hand-foot skin reaction (HFSR) is the most common regorafenib adverse event. However, no intervention has demonstrated efficacy in preventing or palliating this adverse event, short of modulating the regorafenib dose. Methods: The Regorafenib Dose Optimization Study (ReDOS) was a randomized trial ( https://clinicaltrials.gov/ct2/show/NCT02368886 ); here we describe an a priori secondary analysis of ReDOS with the goal of assessing whether clobetasol 0.05% cream (a potent corticosteroid) applied to the palms and soles twice per day is more effective when prescribed pre-emptively (before the development of HFSR) versus reactively (after the development of HFSR). Patients were assessed during the 1st 2 cycles of regorafenib. Results: Among 116 evaluable patients, 61 received pre-emptive clobetasol, and 55 reactive clobetasol. Baseline demographics were comparable between groups. During the 1st regorafenib cycle, 46% and 52% of patients developed HFSR with pre-emptive and reactive clobetasol, respectively (p = 0.52). However, during the 2nd cycle, 56% (of 47 total patients) and 80% (of 41 total patients), developed this toxicity with pre-emptive and reactive clobetasol, respectively (p = 0.02). Of note, during the 2nd cycle, rates of grade 1,2, and 3 HFSR were 40%, 11%, and 4% (pre-emptive) and 45%, 25%, and 10% (reactive) (p = 0.07). A sensitivity analysis to examine rates of no HFSR over all 2 regorafenib cycles showed that no HFSR occurred in 33% (of 61 total patients) with pre-emptive clobetasol versus 15% (of 55 total patients) with reactive clobetasol (p = 0.02). Patient-reported outcomes showed HFSR compromised activities of daily living, including getting dressed, preparing meals, walking, and even driving, with seemingly worse descriptive outcomes in patients who received reactive therapy. No adverse events from clobetasol were reported. Conclusions: Compared to reactive therapy, pre-emptive topical clobetasol might lessen regorafenib-induced HFSR. Clinical trial information: NCT02368886.

188 Background: Unplanned subgroup analyses from several studies have suggested primary tumor sidedness (PTS) as a potential prognostic and predictive parameter in metastatic colorectal cancer (mCRC). We aimed to investigate the prognostic and predictive impact of PTS on outcomes. Methods: PTS data of 7,828 mCRC patients (pts) from 10 first-line randomized trials in the ARCAD database were pooled. PTS was defined as right-sided (RS) or left-sided (LS) if tumor arose from the cecum to the hepatic flexure or from the splenic flexure to the rectum, respectively; transverse colon cancers were not included. Overall survival (OS) and progression-free survival (PFS) were assessed using Kaplan-Meier and Cox models adjusting for age, sex, performance status (PS), prior radiation/chemo, and stratified by treatment arm. Predictive value was tested by interaction term between PTS and treatment (anti-EGFR plus chemotherapy vs. chemotherapy alone). Results: Compared to RS pts (2407, 31%), LS pts (5421, 69%) had better OS (median: 21.6 v 16.8 mos; HRadj: 0.73, 95% CI 0.69-0.78, P < .001) and PFS (median 8.4 v 7.2 mos; HRadj: 0.81, 95% CI 0.76-0.86, P < .001). Results were consistent among subgroups defined by age, sex, PS, metastatic sites and chemo backbone (irinotecan- and oxaliplatin-based). Interaction between PTS and KRAS mutation was significant (Pinteraction< .001): LS is associated with better prognosis only among KRAS wild-type (wt) (HRadj: OS 0.62, 95% CI, 0.55-0.70; PFS 0.71, 95% CI 0.63-0.80), but not among KRAS mutated pts. Among KRAS wt pts, survival benefit from anti-EGFR was observed for LS, but not for RS (table). Conclusions: The prognostic value of PTS is restricted to the KRAS wt population. PTS is predictive of anti-EGFR efficacy, with a significant improvement of survival for LS mCRC pts. These results suggest treatment stratification in mCRC studies by both PTS and KRAS status. [Table: see text]

Abstract Background Diabetes is a prognostic factor for some malignancies, but its association with outcome in patients with advanced or metastatic colorectal cancer (CRC) is less clear. Methods This cohort study was nested within a randomized trial of first-line chemotherapy and bevacizumab and/or cetuximab for advanced or metastatic CRC. Patients were enrolled at 508 community and academic centers throughout the National Clinical Trials Network. The primary exposure was physician-documented diabetes at the time of enrollment. The primary endpoint was overall survival (OS); secondary endpoints were progression-free survival (PFS) and adverse events. Tests of statistical significance were two-sided. Results Among 2326 patients, 378 (16.3%) had diabetes. The median follow-up time was 6.0 years. We observed 1973 OS events and 2173 PFS events. The median time to an OS event was 22.7 months among those with diabetes and 27.1 months among those without diabetes (HR = 1.27, 95% CI = 1.13 to 1.44; P &lt; .001). The median time to a PFS event was 9.7 months among those with diabetes and 10.8 months among those without diabetes (HR = 1.16, 95% CI = 1.03 to 1.30; P = .02). Patients with diabetes were more likely to experience no less than grade 3 hypertension (8.1% vs 4.4%; P = .054) but were not more likely to experience other adverse events, including neuropathy. Conclusions Diabetes is associated with an increased risk of mortality and tumor progression in patients with advanced or metastatic CRC. Patients with diabetes tolerate first-line treatment with chemotherapy and monoclonal antibodies similarly to patients without diabetes.

Abstract Purpose: Previous studies have suggested that higher circulating 25-hydroxyvitamin D [25(OH)D] levels are associated with decreased colorectal cancer risk and improved survival. However, the influence of vitamin D status on disease progression and patient survival remains largely unknown for patients with advanced or metastatic colorectal cancer. Experimental Design: We prospectively collected blood samples in 1,041 patients with previously untreated advanced or metastatic colorectal cancer participating in a randomized phase III clinical trial of first-line chemotherapy plus biologic therapy. We examined the association of baseline plasma 25(OH)D levels with overall survival (OS) and progression-free survival (PFS). Cox proportional hazards models were used to calculate hazard ratios (HRs) and confidence intervals (CIs), adjusted for prognostic factors and confounders. Results: At study entry, 63% of patients were vitamin D deficient (&lt;20 ng/mL) and 31% were vitamin D insufficient (20–&lt;30 ng/mL). Higher 25(OH)D levels were associated with an improvement in OS and PFS (Ptrend = 0.0009 and 0.03, respectively). Compared with patients in the bottom quintile of 25(OH)D (≤10.8 ng/mL), those in the top quintile (≥24.1 ng/mL) had a multivariable-adjusted HR of 0.66 (95% CI, 0.53–0.83) for OS and 0.81 (95% CI, 0.66–1.00) for PFS. The improved survival associated with higher 25(OH)D levels was consistent across patient subgroups of prognostic patient and tumor characteristics. Conclusions: In this large cohort of patients with advanced or metastatic colorectal cancer, higher plasma 25(OH)D levels were associated with improved OS and PFS. Clinical trials assessing the benefit of vitamin D supplementation in patients with colorectal cancer are warranted.

PURPOSERegular physical activity is associated with reduced risk of recurrence and mortality in patients with nonmetastatic colorectal cancer. Its influence on patients with advanced/metastatic colorectal cancer (mCRC) has been largely unexplored.PATIENTS AND METHODSWe conducted a prospective cohort study nested in Cancer and Leukemia Group B (Alliance)/SWOG 80405 (ClinicalTrials.gov identifier: NCT00265850 ), a National Cancer Institute–sponsored phase III trial of systemic therapy for mCRC. Within 1 month after therapy initiation, patients were invited to complete a validated questionnaire that reported average physical activity over the previous 2 months. On the basis of responses, we calculated metabolic equivalent task (MET) hours per week to quantify physical activity. The primary end point of the clinical trial and this companion study was overall survival (OS). Secondary end points included progression-free survival (PFS) and first grade 3 or greater treatment-related adverse events. To minimize confounding by poor and declining health, we excluded patients who experienced progression or died within 60 days of activity assessment and used Cox proportional hazards regression analysis to adjust for known prognostic factors, comorbidities, and weight loss.RESULTSThe final cohort included 1,218 patients. Compared with patients engaged in less than 3 MET hours per week of physical activity, patients engaged in 18 or more MET hours per week experienced an adjusted hazard ratio for OS of 0.85 (95% CI, 0.71 to 1.02; PTrend= .06) and for PFS of 0.83 (95% CI, 0.70 to 0.99; PTrend= .01). Compared with patients engaging in less than 9 MET hours per week, patients engaging in 9 or more MET hours per week experienced an adjusted hazard ratio for grade 3 or greater treatment-related adverse events of 0.73 (95% CI, 0.62 to 0.86; PTrend< .001).CONCLUSIONAmong patients with mCRC in Cancer and Leukemia Group B (Alliance)/SWOG 80405, association of physical activity with OS was not statistically significant. Greater physical activity was associated with longer PFS and lower adjusted risk for first grade 3 or greater treatment-related adverse events.

Abstract Background: In non-metastatic colorectal cancer, a body mass index (BMI) paradox is observed where overweight and early obese patients experience improved outcomes compared to patients with normal, low, or morbidly obese BMI. The influence of obesity on patients with advanced or metastatic colorectal cancer (mCRC) is relatively unexplored. Methods: We conducted a prospective BMI companion study in CALGB (now Alliance for Clinical Trials in Oncology)/SWOG 80405, a phase III mCRC treatment trial. BMI was measured at trial registration. Primary and secondary endpoints were overall and progression-free survival, respectively. To minimize confounding by poor and rapidly declining health, we used Cox proportional hazards regression to adjust for known prognostic factors, comorbidities, physical activity, and weight loss, and excluded individuals with low BMI &lt;21 from statistical tests for trend. We also examined self-reported weight loss over the six months prior to trial enrollment as an independent predictor of patient outcome. Results: In this sub-study of a phase III mCRC trial, BMI was recorded for all 2,323 patients enrolled. Following adjustment for confounders, there were no significant associations between BMI and overall or progression-free survival (excluding BMI &lt;21, Ptrend with increasing BMI = 0.12 and 0.42, respectively). Conversely, weight loss prior to treatment was associated with shorter overall and progression-free survival; compared to individuals with weight change &lt;5%, individuals with weight loss &gt;20% experienced an adjusted hazard ratio of 1.46 for all-cause mortality (95% confidence interval 1.15 to 1.85, Ptrend &lt;.0001) and of 1.27 for disease progression or death (95% confidence interval 1.04 to 1.56, Ptrend = .009). Conclusion: In this prospective study of patients with mCRC, BMI at time of first-line chemotherapy initiation was not associated with patient outcome. Weight loss prior to study entry was associated with increased risk of patient mortality and disease progression. Citation Format: Brendan Guercio, Sui Zhang, Alan P. Venook, Fang-Shu Ou, Donna Niedzwiecki, Heinz-Josef Lenz, Federico Innocenti, Hanna Sanoff, Michelle R. Mahoney, Bert H. O'Neil, James E. Shaw, Blase N. Polite, Howard S. Hochster, James N. Atkins, Richard M. Goldberg, Robert J. Mayer, Charles D. Blanke, Charles S. Fuchs, Jeffrey A. Meyerhardt. Body mass index, weight loss, and progression and mortality in metastatic colorectal cancer: Results from CALGB/SWOG 80405 (Alliance) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3285.

PURPOSE: To describe the frequency, content, dynamics, and patterns of cost conversations in academic medical oncology across tumor types. PATIENTS AND METHODS: We reviewed 529 audio recordings between May 3, 2012, to September 23, 2014, from a prospective three-site communication study in which patients at any stage of management for any solid tumor malignancy were seen in routine oncology appointments. Recordings were deidentified, transcribed, and flagged for any mention of cost. We coded encounters and used qualitative thematic analysis. RESULTS: Financial issues were discussed in 151 (28%) of 529 recordings. Conversations lasted shorter than 2 minutes on average. Patients/caregivers raised a majority of discussions (106 of 151), and 40% of cost concerns raised by patients/caregivers were not verbally acknowledged by clinicians. Social service referrals were made only six times. Themes from content analysis were related to insurance eligibility/process, work insecurity, cost of drugs, cost used as tool to influence medical decision making, health care–specific costs, and basic needs. Financial concerns influenced oncology work processes via test or medication coverage denials, creating paperwork for clinicians, potentially influencing patient involvement in trials, and leading to medication self-rationing or similar behaviors. Typically, financial concerns were associated with negative emotions. CONCLUSION: Financial issues were raised in approximately one in four academic oncology visits. These brief conversations were usually initiated by patients/caregivers, went frequently unaddressed by clinicians, and seemed to influence medical decision making and work processes and contribute to distress. Themes identified shed light on the kinds of gaps that must be addressed to help patients with cancer cope with the rising cost of care.

e18367 Background: Regorafenib at 160mg daily 21/28 days is a standard therapeutic option in patients with metastatic colorectal cancer. However, the cost of treatment and management of its side-effects is more than the cost-effectiveness threshold for oncology drugs in US and many countries around the world. ReDOS (Regorafenib Dose Optimization Study), is a randomized phase II trial in refractory mCRC and established that weekly dose escalation of regorafenib over the conventional dosing is superior in the composite endpoint of safety and efficacy. We explored the impact of the new dosing strategy on CE of regorafenib. Methods: A Markov model was constructed to compare costs and effectiveness of regorafenib (standard), regorafenib (ReDOS), and best supportive care (BSC). Model inputs for clinical efficacy and safety were from the CORRECT trial for regorafenib (standard) and BSC, and the ReDOS study for regorafenib (ReDOS). The incremental cost-effectiveness ratios (ICERs) were reported to compare treatments. Model robustness was checked with univariate and probabilistic sensitivity analyses. The model used a US payer’s perspective with 5% annual discount rate, and all costs were measured in 2018 US dollars. Results: Regorafenib (ReDOS) dominated regorafenib (standard), producing higher quality-adjusted life years at a lower cost. When compared to BSC, regorafenib (ReDOS) resulted in the ICER of $112,705 while regorafenib (standard) resulted in the ICER of $384,687. The most influential parameters on the ICERs were efficacy and health state utility parameters under univariate sensitivity analysis. In probabilistic sensitivity analysis using cost-effectiveness acceptability curves, regorafenib (ReDOS) was more cost-effective than regorafenib (standard) and BSC in 70% of repetition at the willingness-to-pay threshold of $120,000 per QALY (Quality-Adjusted Life Year) and 98% at a WTP threshold of $150,000. Conclusions: Based on the outcomes demonstrated in the ReDOS study, the dose optimization strategy of regorafenib results in favorable cost-effectiveness under a typical US willingness-to-pay threshold of $150,000 per QALY.