Green, Erin M.

Purpose Previous studies have suggested that higher plasma 25-hydroxyvitamin D3 [25(OH)D] levels are associated with decreased colorectal cancer risk and improved survival, but the prevalence of vitamin D deficiency in advanced colorectal cancer and its influence on outcomes are unknown. Patients and Methods We prospectively measured plasma 25(OH)D levels in 515 patients with stage IV colorectal cancer participating in a randomized trial of chemotherapy. Vitamin D deficiency was defined as 25(OH)D lower than 20 ng/mL, insufficiency as 20 to 29 ng/mL, and sufficiency as ≥ 30 ng/mL. We examined the association between baseline 25(OH)D level and selected patient characteristics. Cox proportional hazards models were used to calculate hazard ratios (HR) for death, disease progression, and tumor response, adjusted for prognostic factors. Results Among 515 eligible patients, 50% of the study population was vitamin D deficient, and 82% were vitamin D insufficient. Plasma 25(OH)D levels were lower in black patients compared to white patients and patients of other race (median, 10.7 v 21.1 v 19.3 ng/mL, respectively; P < .001), and females compared to males (median, 18.3 v 21.7 ng/mL, respectively; P = .0005). Baseline plasma 25(OH)D levels were not associated with patient outcome, although given the distribution of plasma levels in this cohort, statistical power for survival analyses were limited. Conclusion Vitamin D deficiency is highly prevalent among patients with stage IV colorectal cancer receiving first-line chemotherapy, particularly in black and female patients.

Background Data collection and review were identified as major contributors to the cost of randomized clinical trials (RCTs). Purpose We proposed and assessed a novel alternative for long-term clinical trial follow-up based on the data captured through an accredited Cancer Registry (CR) that is part of the National Cancer Database (NCDB). Methods Patients from Mayo Clinic, Rochester, enrolled in the North Central Cancer Treatment Group N934653 (COST) trial (98 patients) and the American College of Surgeons Oncology Group Z0030 trial (55 patients) were included in the study. Demographic, treatment, and long-term outcome data were compared between the hospital-based CR and the RCTs’ databases. Concordances were used to estimate the agreement between two databases. Kaplan—Meier curves were plotted to examine the consistency of time-to-event long-term outcomes of the CR and RCT databases. Results High concordances (>95%) were observed for most demographic and treatment variables between the CR data and RCT data. The vital status concordances were 100% and 94.5% between the CR and COST and Z0030 databases, respectively. Three discrepant death dates were observed, one in the COST trial and two in the Z0030 trial. The concordances of disease-free status between the CR and RCT databases were 99.0% and 87.3%, and 15 discrepant disease recurrence cases were identified: 4 for COST and 11 for Z0030. Limitations The analysis has been focused on patients from a single site, Mayo Clinic, Rochester, enrolled in two large RCT evaluating surgical treatments. The findings herein need to be confirmed in a broader setting, such as multi-center, multi-registry including nonsurgical trials. Conclusions CR data were nearly identical to data from two randomized phase III trials in different disease types and conducted by two different cooperative groups. The NCDB Cancer Registries represent a feasible alternative for obtaining long-term follow-up data for large clinical trials. Clinical Trials 2010; 7: 686—695. http:// ctj.sagepub.com

Purpose With three available chemotherapy drugs for advanced colorectal cancer (CRC), response rate (RR) and survival outcomes have improved with associated morbidity, accentuating the need for tools to select optimal individualized treatment. Pharmacogenetics identifies the likelihood of adverse events or response based on variants in genes involved in drug transport, metabolism, and cellular targets. Patients and Methods Germline DNA was extracted from 520 patients on the North American Gastrointestinal Intergroup N9741 study. Three study arms were evaluated: IFL (fluorouracil [FU] + irinotecan [IRN]), FOLFOX (FU + oxaliplatin), and IROX (IRN + oxaliplatin). Information on adverse events, response, and disease-free survival was available. Thirty-four variants in 15 candidate genes for analysis based on previous associations with adverse events or outcome were assessed. Genotyping was performed using pyrosequencing. Results All variants were polymorphic. The homozygous UGT1A1*28 allele observed in 9% of patients was associated with risk of grade 4 neutropenia in patients on IROX (55% v 15%; P = .002). Deletion in GSTM1 was associated with grade 4 neutropenia after FOLFOX (28% v 16%; P = .02). Patients with a homozygous variant genotype for GSTP1 were more likely to discontinue FOLFOX because of neurotoxicity (24% v 10%; P = .01). The presence of a CYP3A5 variant was significantly associated with RR on IFL (29% v 60%; P = .0074). Most previously published genotype-toxicity or -efficacy relationships were not validated in this study. Conclusion This study provides a platform to evaluate pharmacogenetic predictors of response or severe adverse events in advanced CRC. Pharmacogenetic studies can be conducted in multicenter trials, and our findings demonstrate that with continued research, clinical application is practical.

Purpose Racial disparities in colorectal cancer (CRC) survival are documented, but there are few data on comparative response to chemotherapy. A subgroup analysis of a multisite National Cancer Institute–sponsored trial (N9741) was performed comparing outcomes of black and white patients with metastatic CRC receiving uniform treatment. Patients and Methods Adverse events (AEs), response rate (RR), time to progression (TTP), overall survival (OS), and dose-intensity were examined as a function of self-reported race in 1,412 patients treated with irinotecan/fluorouracil, fluorouracil/oxaliplatin, or irinotecan/oxaliplatin. Pharmacogenetic analysis was performed on 486 patients with blood available for germline DNA analysis. Results OS was 1.5 months shorter and TTP was 0.6 months shorter in black than white patients (OS: hazard ratio [HR] = 1.13; 95% CI, 0.90 to 1.42; TTP: HR = 0.91, 95% CI, 0.73 to 1.13); neither difference was statistically significant. RR was significantly higher in whites (41%) than blacks (28%; P = .008). Grade 3 or greater AEs were also higher in whites (48%) than blacks (34%; P = .004). These relationships were maintained in multivariate models adjusting for arm, age, sex, and performance status. There was no difference in dose-intensity of delivered therapy. Significant racial differences in prevalence of pharmacogenetic variants were observed, although small sample size precluded investigating the relationship between treatment, race, and genotype. Conclusion OS and TTP are similar in black and white patients treated per protocol with standardized therapy for metastatic CRC. However, RR and AEs vary considerably by race. The marked racial differences in relevant pharmacogenetics, a potential explanation for differing RR and AEs, are worthy of future study.

Abstract Purpose: Insulin-like growth factor (IGF)-I and IGF-II stimulate neoplastic cell growth and inhibit apoptosis, whereas IGF-binding protein-3 (IGFBP-3) inhibits the bioavailability of IGF-I and has independent proapoptotic activity. We examined the influence of baseline plasma levels of IGF-I, IGF-II, IGFBP-3, and C-peptide on outcome among patients receiving first-line chemotherapy for metastatic colorectal cancer. Experimental Design: The plasma levels of IGF-I, IGF-II, IGFBP-3, and C-peptide as well as data on prognostic factors and body size were measured at baseline among 527 patients participating in a randomized trial of first-line chemotherapy for metastatic colorectal cancer. Results: Higher baseline plasma IGFBP-3 levels were associated with a significantly greater chemotherapy response rate (P = 0.03) after adjusting for other prognostic factors, whereas neither IGF-I nor IGF-II levels significantly predicted tumor response. Higher levels of IGF-I, IGF-II, and IGFBP-3 were all univariately associated with improved overall survival (P = 0.0001 for all). In a model that mutually adjusted for IGF-I and IGFBP-3, as well as other prognostic factors, increasing baseline-circulating IGFBP-3 was associated with a significantly longer time to tumor progression (P = 0.03), whereas circulating IGF-I was not associated with disease progression (P = 0.95). Levels of C-peptide were not associated with any measure of patient outcome. Conclusion: Among colorectal cancer patients receiving first-line chemotherapy, increasing levels of IGFBP-3, an endogenous antagonist to IGF-I, are associated with an improved objective treatment response and a prolonged time to cancer progression. The IGF pathway may represent an important target for future treatment strategies.

Abstract The cyclooxygenase (COX)-2 enzyme appears to be an important target for cancer chemoprevention. Given the recent emergence of potentially serious cardiovascular toxicity associated with selective COX-2 inhibitors, nonsteroidal antiinflammatory drugs (NSAIDs), which inhibit both COX-1 and COX-2, have received renewed attention as candidate chemoprevention agents. Sulindac has shown consistent chemopreventive potential in preclinical studies as well as in a limited number of clinical trials reported to date. For the current pharmacokinetic study, sulindac capsules were prepared to facilitate ample agent supplies for future intervention studies. Encapsulation of the parent compound (sulindac sulfoxide) can be readily accomplished, but the effects of alternate formulations on bioavailability have not been rigorously examined. In the present single-dose, two-period crossover trial, we conducted pharmacokinetic analyses of sulindac in capsule (test) versus tablet (reference) formulations. Overall, bioavailability appeared to be higher for the capsule compared with the tablet formulation based on test-to-reference pharmacokinetic variable ratios for the parent compound alone. However, additional analyses based on the sulfide and sulfone metabolites of sulindac with the same pharmacokinetic variables indicated similar chemopreventive exposures between the capsule and tablet formulations. These data support the use of sulindac capsules, which can be readily prepared with matching placebos, in future blinded chemoprevention trials. (Cancer Epidemiol Biomarkers Prev 2008;17(3):674–9)

Purpose To evaluate clinical characteristics and survival outcomes among patients with locally advanced or metastatic colorectal cancer who achieve a complete response (CR) to systemic treatment either alone or with multimodality approach. Patients and Methods Data were collected retrospectively from CRC patients enrolled onto the phase III trial N9741, a National Cancer Institute–funded and Gastrointestinal Cancer Intergroup–sponsored study coordinated by the North Central Cancer Treatment Group. Patients were randomly assigned to combinations of oxaliplatin, fluorouracil (FU)/leucovorin (LV) and irinotecan. The three treatment arms consist of IFL (irinotecan + FU/LV), FOLFOX4 (oxaliplatin + FU/LV), and IROX (irinotecan + oxaliplatin). Median follow-up was 42.6 months. Results Sixty-two (4%) of 1,508 patients had a CR to chemotherapy alone, and an additional 32 (2%) had a CR after multimodality treatment. Factors associated with achieving CR with systemic chemotherapy alone included FOLFOX4 treatment, patients with assessable disease, or a single site of metastasis. Continuing protocol treatment beyond two cycles after documentation of CR was not associated with improved survival. The rate of curative intent resection was significantly higher for patients treated with oxaliplatin-containing regimens (P = .02). Median survival was similar between patients with CR after chemotherapy alone (44.3 months) or after multimodality approach (47.4 months; P = .81). Conclusion FOLFOX4 was more likely to produce a CR than were IFL or IROX. Oxaliplatin regimens were more likely to result in successful surgical resections. Patients who have CR to systemic chemotherapy alone can achieve impressive survival outcomes similar to those seen among patients who attained a CR status after multimodality treatment.

OBJECTIVE—The Mayo Health System Diabetes Translation Project sought to assess models of community-based diabetes care and use of a diabetes electronic management system (DEMS). Planned care is a redesigned model of chronic disease care that involves guideline implementation, support of self-management, and use of clinical information systems. RESEARCH DESIGN AND METHODS—We studied adult diabetic patients attending three primary care practice sites in Wisconsin and Minnesota. We implemented planned care at all sites and DEMS in the practice of 16 primary care providers. We assessed quality of diabetes care using standard indicators for 200 patients randomly selected from each site at baseline and at 24 months of implementation. We used multivariable analyses to estimate the association between planned care and DEMS and each quality indicator. RESULTS—Planned care was associated with improvements in measurement of HbA1c (odds ratio 7.0 [95% CI 4.2–11.6]), HDL cholesterol (5.6 [4.1–7.5]), and microalbuminuria (5.3 [3.5–8.0]), as well as the provision of tobacco advice (6.9 [4.7–10.1]), among other performance measures. DEMS use was associated with improvements in all indicators, including microalbuminuria (3.2 [1.9–5.2]), retinal examination (2.4 [1.5–3.9]), foot examinations (2.3 [1.2–4.4]), and self-management support (2.6 [1.7–3.8]). Although planned care was associated with improvements in metabolic control, we observed no additional metabolic benefit when providers used DEMS. CONCLUSIONS—Planned care was associated with improved performance and metabolic outcomes in primary care. DEMS use augmented the impact of planned care on performance outcomes but not on metabolic outcomes. Optimal identification of the best translation of evidence to diabetes practice will require longer follow-up or new care-delivery models.