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.

Pharmacogenetic study in gastric cancer patients treated with adjuvant fluorouracil/leucovorin or epirubicin/cisplatin/fluorouracil before and after chemoradiation on CALGB 80101 (Alliance).

There is a lack of pharmacogenetic predictors of outcome in gastric cancer patients. The aim of this study was to assess previously identified candidate genes associated with 5-fluorouracil (5-FU), cisplatin, or epirubicin toxicity or response in a cohort of resected gastric cancer patients treated on CALGB (Alliance) 80101. Gastric or gastroesophageal cancer patients randomized to adjuvant 5-FU/leucovorin or epirubicin/cisplatin/5-FU before and after 5-FU chemoradiation were genotyped for single nucleotide polymorphisms (SNPs) in GSTP1 (rs1695), ERCC1 (rs11615 and rs3212986), XRCC1 (rs25487), UGT2B7 (rs7439366) and the 28 base-pair tandem repeats in TYMS (rs34743033). Logistic regression and log rank tests were used to assess the association between each SNP and incidence of grade 3/4 neutropenia and leukopenia, overall (OS) and progression-free survival (PFS), respectively. Toxicity endpoint analyses were adjusted for the treatment arm, while OS and PFS were also adjusted for performance status, sex, age, lymph node involvement, and primary tumor site and size. Of 281 subjects with successful genotyping results and available clinical (toxicity and efficacy) data, 166 self-reported non-Hispanic White patients were included in the final analysis. There was a lack of evidence of an association among any SNPs tested with grade 3/4 neutropenia and leukopenia or OS and PFS. Age, lymph node involvement, and primary tumor size were significantly associated with OS and PFS. This study failed to confirm results of previous gastric cancer pharmacogenetic studies.

Benefit of Oxaliplatin in Stage III Colon Cancer According to IDEA Risk Groups: Findings from the ACCENT Database of 4934 Patients.

BACKGROUND: The International Duration Evaluation of Adjuvant Chemotherapy (IDEA) pooled analysis compared 3 to 6 months of adjuvant chemotherapy for stage III colon cancer. Patients were classified into low risk and high risk, suggesting low-risk patients may be offered only 3 months of treatment. In this study, we aimed to assess the benefit of oxaliplatin in the adjuvant setting per IDEA risk groups, using data from 3 large adjuvant phase III studies, namely Multicenter International Study of Oxaliplatin/Fluorouracil/ Leucovorin in the Adjuvant Treatment of Colon Cancer (MOSAIC), C-07, and XELOXA. METHODS: Using the MOSAIC, C-07, and XELOXA previously published studies, we identified 2810 low-risk and 2124 high-risk patients with stage III colon cancer. We used Cox regression model to evaluate the magnitude of survival differences between IDEA risk groups, according to oxaliplatin use. Based on design similarity and equivalent follow-up data, MOSAIC and C-07 were pooled, whereas XELOXA was analyzed separately. Subgroup analyses were also performed for T4 and/or N2 patients. RESULTS: Individuals with IDEA low and high risk derived overall survival benefit from the addition of oxaliplatin to adjuvant chemotherapy, with adjusted hazard ratios of 0.79 (0.66-0.95) and 0.84 (0.71-0.99), respectively. Among individuals with IDEA high risk, those with T4 disease did not gain overall survival benefit from addition of oxaliplatin with hazard ratio of 0.95 (0.71-1.27). Similar results were demonstrated using data from the XELOXA study. CONCLUSION: IDEA risk classification per se does not predict benefit from addition of oxaliplatin to adjuvant chemotherapy in stage III colon cancer. T4 disease may predict lack of benefit from oxaliplatin addition.

Sex and Adverse Events of Adjuvant Chemotherapy in Colon Cancer: An Analysis of 34 640 Patients in the ACCENT Database.

BACKGROUND: Adjuvant chemotherapy is a standard treatment option for patients with stage III and high-risk stage II colon cancer. Sex is one of several factors responsible for the wide inter-patient variability in drug responses. Amalgamated data on the effect of sex on the toxicity of current standard adjuvant treatment for colorectal cancer are missing. METHODS: The objective of our study was to compare incidence and severity of major toxicities of fluoropyrimidine- (5FU or capecitabine) based adjuvant chemotherapy, with or without oxaliplatin, between male and female patients after curative surgery for colon cancer. Adult patients enrolled in 27 relevant randomized trials included in the ACCENT (Adjuvant Colon Cancer End Points) database, a large, multi-group, international data repository containing individual patient data, were included. Comparisons were conducted using logistic regression models (stratified by study and treatment arm) within each type of adjuvant chemotherapy (5FU, FOLFOX, capecitabine, CAPOX, and FOLFIRI). The following major toxicities were compared (grade III or IV and grade I-IV, according to National Cancer Institute Common Terminology Criteria [NCI-CTC] criteria, regardless of attribution): nausea, vomiting, nausea or vomiting, stomatitis, diarrhea, leukopenia, neutropenia, thrombocytopenia, anemia, and neuropathy (in patients treated with oxaliplatin). RESULTS: Data from 34 640 patients were analyzed. Statistically significant and clinically relevant differences in the occurrence of grade III or IV nonhematological {especially nausea (5FU: odds ratio [OR] = 2.33, 95% confidence interval [CI] = 1.90 to 2.87, P < .001; FOLFOX: OR = 2.34, 95% CI = 1.76 to 3.11, P < .001), vomiting (5FU: OR = 2.38, 95% CI = 1.86 to 3.04, P < .001; FOLFOX: OR = 2.00, 95% CI = 1.50 to 2.66, P < .001; CAPOX: OR = 2.32, 95% CI = 1.55 to 3.46, P < .001), and diarrhea (5FU: OR = 1.35, 95% CI = 1.21 to 1.51, P < .001; FOLFOX: OR = 1.60, 95% CI = 1.35 to 1.90, P < .001; FOLFIRI: OR = 1.57, 95% CI = 1.25 to 1.97, P < .001)} as well as hematological toxicities (neutropenia [5FU: OR = 1.55, 95% CI = 1.37 to 1.76, P < .001; FOLFOX: OR = 1.96, 95% CI = 1.71 to 2.25, P < .001; FOLFIRI: OR = 2.01, 95% CI = 1.66 to 2.43, P < .001; capecitabine: OR = 4.07, 95% CI = 1.84 to 8.99, P < .001] and leukopenia [5FU: OR = 1.74, 95% CI = 1.40 to 2.17, P < .001; FOLFIRI: OR = 1.75, 95% CI = 1.28 to 2.40, P < .001]) were observed, with women being consistently at increased risk. CONCLUSIONS: Our analysis confirms that women with colon cancer receiving adjuvant fluoropyrimidine-based chemotherapy are at increased risk of toxicity. Given the known sex differences in fluoropyrimidine pharmacokinetics, sex-specific dosing of fluoropyrimidines warrants further investigation.

Intergroup Randomized Phase III Study of Postoperative Oxaliplatin, 5-Fluorouracil, and Leucovorin Versus Oxaliplatin, 5-Fluorouracil, Leucovorin, and Bevacizumab for Patients with Stage II or III Rectal Cancer Receiving Preoperative Chemoradiation: A Trial of the ECOG-ACRIN Research Group (E5204).

BACKGROUND: The addition of bevacizumab to chemotherapy improved outcomes for patients with metastatic colon cancer. E5204 was designed to test whether the addition of bevacizumab to mFOLFOX6, following neoadjuvant chemoradiation and definitive surgery, could improve overall survival (OS) in patients with stage II/III adenocarcinoma of the rectum. SUBJECTS, MATERIALS, AND METHODS: Patients with stage II/III rectal cancer who had completed neoadjuvant 5-fluorouracil-based chemoradiation and had undergone complete resection were enrolled. Patients were randomized to mFOLFOX6 (Arm A) or mFOLFOX6 with bevacizumab (Arm B) administered every 2 weeks for 12 cycles. RESULTS: E5204 registered only 355 patients (17% of planned accrual goal) as it was terminated prematurely owing to poor accrual. At a median follow-up of 72 months, there was no difference in 5-year overall survival (88.3% vs. 83.7%) or 5-year disease-free survival (71.2% vs. 76.5%) between the two arms. The rate of treatment-related grade ≥ 3 adverse events (AEs) was 68.8% on Arm A and 70.7% on Arm B. Arm B had a higher proportion of patients who discontinued therapy early as a result of AEs and patient withdrawal than did Arm A (32.4% vs. 21.5%, p = .029).The most common grade 3-4 treatment-related AEs were neutropenia, leukopenia, neuropathy, diarrhea (without prior colostomy), and fatigue. CONCLUSION: At 17% of its planned accrual, E5204 did not meet its primary endpoint. The addition of bevacizumab to FOLFOX6 in the adjuvant setting did not significantly improve OS in patients with stage II/III rectal cancer. IMPLICATIONS FOR PRACTICE: At 17% of its planned accrual, E5204 was terminated early owing to poor accrual. At a median follow-up of 72 months, there was no significant difference in 5-year overall survival (88.3% vs. 83.7%) or in 5-year disease-free survival (71.2% vs. 76.5%) between the two arms. Despite significant advances in the treatment of rectal cancer, especially in improving local control rates, the risk of distant metastases and the need to further improve quality of life remain a challenge. Strategies combining novel agents with chemoradiation to improve both distant and local control are needed.

Adjuvant Chemoradiotherapy With Epirubicin, Cisplatin, and Fluorouracil Compared With Adjuvant Chemoradiotherapy With Fluorouracil and Leucovorin After Curative Resection of Gastric Cancer: Results From CALGB 80101 (Alliance).

Purpose After curative resection of gastric or gastroesophageal junction adenocarcinoma, Intergroup Trial 0116 (Phase III trial of postoperative adjuvant radiochemotherapy for high risk gastric and gastroesophageal junction adenocarcinoma: Demonstrated superior survival for patients who received postoperative chemoradiotherapy with bolus fluorouracil (FU) and leucovorin (LV) compared with surgery alone. CALGB 80101 (Alliance; Phase III Intergroup Trial of Adjuvant Chemoradiation After Resection of Gastric or Gastroesophageal Adenocarcinoma) assessed whether a postoperative chemoradiotherapy regimen that replaced FU plus LV with a potentially more active systemic therapy could further improve overall survival. Patients and Methods Between April 2002 and May 2009, 546 patients who had undergone a curative resection of stage IB through IV (M0) gastric or gastroesophageal junction adenocarcinoma were randomly assigned to receive either postoperative FU plus LV before and after combined FU and radiotherapy (FU plus LV arm) or postoperative epirubicin, cisplatin, and infusional FU (ECF) before and after combined FU and radiotherapy (ECF arm). Results With a median follow-up duration of 6.5 years, 5-year overall survival rates were 44% in the FU plus LV arm and 44% in the ECF arm ( Plogrank = .69; multivariable hazard ratio, 0.98; 95% CI, 0.78 to 1.24 comparing ECF with FU plus LV). Five-year disease-free survival rates were 39% in the FU plus LV arm and 37% in the ECF arm ( Plogrank = .94; multivariable hazard ratio, 0.96; 95% CI, 0.77 to 1.20). In post hoc analyses, the effect of treatment seemed to be similar across all examined patient subgroups. Conclusion After a curative resection of gastric or gastroesophageal junction adenocarcinoma, postoperative chemoradiotherapy using a multiagent regimen of ECF before and after radiotherapy does not improve survival compared with standard FU and LV before and after radiotherapy.

Impact of Patient Factors on Recurrence Risk and Time Dependency of Oxaliplatin Benefit in Patients With Colon Cancer: Analysis From Modern-Era Adjuvant Studies in the Adjuvant Colon Cancer End Points (ACCENT) Database.

PURPOSE: Fluorouracil plus leucovorin (FU + LV) adjuvant chemotherapy reduced the risk of recurrence and death across all time points in a pooled analysis of 20,898 patients with colon cancer from 18 randomized studies. The impact of oxaliplatin added to FU + LV on the time course of recurrence and survival remains unknown. PATIENTS AND METHODS: A total of 12,233 patients enrolled to the randomized trials C-07, C-08, N0147, MOSAIC (Adjuvant Treatment of Colon Cancer), and XELOXA (Adjuvant XELOX) were pooled to examine the impact of oxaliplatin and tumor-specific factors on the time course of recurrence and death. For each end point, continuous-time risk was modeled over 6 years post treatment in all oxaliplatin-treated patients and patients concurrently randomized to FU + LV with or without oxaliplatin; the latter analyses supported time-dependent treatment comparisons. RESULTS: Addition of oxaliplatin significantly reduced the risk of recurrence within the first 14 months post treatment for patients with stage II disease and within the first 4 years for patients with stage III disease. Oxaliplatin also significantly reduced risk of death from 2 to 6 years post treatment for patients with stage III disease, with no differences in timing of outcomes between treatment groups (ie, oxaliplatin did not simply postpone recurrence or death compared with FU + LV alone). Patients with stage II disease receiving oxaliplatin did not exhibit a significant reduction in risk of death in the first 6 years post treatment. Recurrence risk peaked near 14 months for both treatments, and risk of recurrence and death increased with increased tumor and nodal burden. CONCLUSIONS: These analyses support the addition of oxaliplatin to fluoropyrimidine-based adjuvant therapy in patients with stage III disease and underscore the need for adequate surveillance of patients with colon cancer during the first 3 years after adjuvant therapy.

Capecitabine Plus Oxaliplatin Compared With Fluorouracil/Folinic Acid As Adjuvant Therapy for Stage III Colon Cancer: Final Results of the NO16968 Randomized Controlled Phase III Trial.

PURPOSE: To report the final efficacy findings and biomarker analysis from the NO16968 trial comparing bolus fluorouracil/folinic acid (FU/FA) with capecitabine plus oxaliplatin (XELOX) in resected stage III colon cancer. PATIENTS AND METHODS: After curative resection, patients were randomly assigned to receive XELOX, as oxaliplatin 130 mg/m(2) on day 1 and capecitabine 1,000 mg/m(2) twice daily on days 1 to 14 every 3 weeks, or bolus FU/FA, as the Mayo Clinic or Roswell Park regimens, for 6 months. The primary end point was disease-free survival (DFS). Secondary end points included overall survival (OS). RESULTS: The intention-to-treat population comprised 1,886 patients (XELOX, n = 944; FU/FA, n = 942). Seven-year DFS rates were 63% and 56% in the XELOX and FU/FA groups, respectively (hazard ratio [HR], 0.80; 95% CI, 0.69 to 0.93; P = .004). Seven-year OS rates were 73% and 67% in the XELOX and FU/FA groups, respectively (HR, 0.83; 95% CI, 0.70 to 0.99; P = .04). A total of 68% and 77% of patients who experienced relapse or a new colorectal cancer in the XELOX and FU/FA groups, respectively, received drug treatment for metastatic disease. Four hundred ninety-eight patients consented to the biomarker analysis: 242 in the XELOX group and 256 in the FU/FA group. Low tumor expression of dihydropyrimidine dehydrogenase may be predictive for XELOX efficacy; in the XELOX group, for high versus low dihydropyrimidine dehydrogenase expression levels, DFS HR was 2.45 (95% CI, 1.55 to 3.86; P < .001), and OS HR was 2.75 (95% CI, 1.65 to 4.59; P < .001). In the FU/FA group, no statistically significant associations were observed between any tumor biomarker and outcomes. CONCLUSION: XELOX improved OS compared with bolus FU/FA in patients with resected stage III colon cancer after a median follow-up of almost 7 years. XELOX should be considered a standard adjuvant treatment option in patients with stage III disease. Tumoral dihydropyrimidine dehydrogenase expression is a promising predictive, and potentially, highly clinically relevant, biomarker for XELOX efficacy requiring further prospective evaluation.

Comparison of outcomes after fluorouracil-based adjuvant therapy for stages II and III colon cancer between 1978 to 1995 and 1996 to 2007: evidence of stage migration from the ACCENT database.

PURPOSE: With improved patient care, better diagnosis, and more treatment options after tumor recurrence, outcomes after fluorouracil (FU) -based treatment are expected to have improved over time in early-stage colon cancer. Data from 18,449 patients enrolled onto 21 phase III trials conducted from 1978 to 2002 were evaluated for potential differences in time to recurrence (TTR), time from recurrence to death (TRD), and overall survival (OS) with regard to FU-based adjuvant regimens. METHODS: Trials were predefined as old versus newer era using initial accrual before or after 1995. Outcomes were compared between patients enrolled onto old- or newer-era trials, stratified by stage. RESULTS: Within the first 3 years, recurrence rates were lower in newer- versus old-era trials for patients with stage II disease, with no differences among those with stage III disease. Both TRD and OS were significantly longer in newer-era trials overall and within each stage. The lymph node (LN) ratio (ie, number of positive nodes divided by total nodes harvested) in those with stage III disease declined over time. TTR improved slightly, with larger number of LNs examined in both stages. CONCLUSION: Improved TRD in newer trials supports the premise that more aggressive intervention (oxaliplatin- and irinotecan-based chemotherapy and/or surgery for recurrent disease) improves OS for patients previously treated in the adjuvant setting. Lower recurrence rates with identical treatments in those with stage II disease enrolled onto newer-era trials reflect stage migration over time, calling into question historical data related to the benefit of FU-based adjuvant therapy in such patients.

Impact of age on the efficacy of newer adjuvant therapies in patients with stage II/III colon cancer: findings from the ACCENT database.

PURPOSE: Prior studies have suggested that patients with stage II/III colon cancer receive similar benefit from intravenous (IV) fluoropyrimidine adjuvant therapy regardless of age. Combination regimens and oral fluorouracil (FU) therapy are now standard. We examined the impact of age on colon cancer recurrence and mortality after adjuvant therapy with these newer options. PATIENTS AND METHODS: We analyzed 11,953 patients age < 70 and 2,575 age ≥ 70 years from seven adjuvant therapy trials comparing IV FU with oral fluoropyrimidines (capecitabine, uracil, or tegafur) or combinations of fluoropyrimidines with oxaliplatin or irinotecan in stage II/III colon cancer. End points were disease-free survival (DFS), overall survival (OS), and time to recurrence (TTR). RESULTS: In three studies comparing oxaliplatin-based chemotherapy with IV FU, statistically significant interactions were not observed between treatment arm and age (P interaction = .09 for DFS, .05 for OS, and .36 for TTR), although the stratified point estimates suggested limited benefit from the addition of oxaliplatin in elderly patients (DFS hazard ratio [HR], 0.94; 95% CI, 0.78 to 1.13; OS HR, 1.04; 95% CI, 0.85 to 1.27). No significant interactions by age were detected with oral fluoropyrimidine therapy compared with IV FU; noninferiority was supported in both age populations. CONCLUSION: Patients age ≥ 70 years seemed to experience reduced benefit from adding oxaliplatin to fluoropyrimidines in the adjuvant setting, although statistically, there was not a significant effect modification by age, whereas oral fluoropyrimidines retained their efficacy.

Updated analysis of SWOG-directed intergroup study 0116: a phase III trial of adjuvant radiochemotherapy versus observation after curative gastric cancer resection.

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

Capecitabine plus oxaliplatin compared with fluorouracil and folinic acid as adjuvant therapy for stage III colon cancer.

PURPOSE: This multicenter, randomized trial compared capecitabine plus oxaliplatin (XELOX) with bolus fluorouracil (FU) and folinic acid (FA) as adjuvant therapy for patients with stage III colon cancer. PATIENTS AND METHODS: Patients who had undergone curative resection were randomly assigned to XELOX (oxaliplatin 130 mg/m(2) on day 1 plus capecitabine 1,000 mg/m(2) twice daily on days 1 to 14 every 3 weeks for 24 weeks) or a standard bolus FU/FA adjuvant regimen (Mayo Clinic for 24 weeks or Roswell Park for 32 weeks). The primary study end point was disease-free survival (DFS). RESULTS: The intention-to-treat population comprised 1,886 patients; 944 patients were randomly assigned to XELOX and 942 to FU/FA (Mayo Clinic, n = 664; Roswell Park, n = 278). After 57 months of follow-up for the primary analysis, 295 patients (31.3%) in the XELOX group had relapsed, developed a new primary colon cancer, or died compared with 353 patients (37.5%) in the FU/FA group (hazard ratio [HR] for DFS, 0.80; 95% CI, 0.69 to 0.93; P = .0045). The 3-year DFS rate was 70.9% with XELOX and 66.5% with FU/FA. The HR for overall survival (OS) for XELOX compared to FU/FA was 0.87 (95% CI, 0.72 to 1.05; P = .1486). The 5-year OS for XELOX and FU/FA were 77.6% and 74.2%, respectively. Follow-up is ongoing. Preplanned multivariate and subgroup analyses supported the robustness of these findings. CONCLUSION: The addition of oxaliplatin to capecitabine improves DFS in patients with stage III colon cancer. XELOX is an additional adjuvant treatment option for these patients.

Improved patient and regimen selection in locally advanced rectal cancer: who, how, and what next?

Before the advent of neoadjuvant chemoradiation therapy (NCRT) for locally advanced rectal cancer, local failure represented half of treatment failures. The German Rectal Cancer Study Group trial demonstrated that NCRT along with total mesorectal excision can improve local control and the rate of sphincter-preserving surgery. Thus, the National Comprehensive Cancer Network now recommends NCRT as the standard of care for stage III and IV rectal cancer. Recent trials and analysis have questioned accepted wisdom regarding patient selection for NCRT and methods of administration. EORTC 22921 demonstrated that the addition of chemotherapy to radiation therapy, regardless of timing, improved local control but not overall survival, and subgroup analysis from this study generated the hypothesis that the subgroup of patients with good pathologic response to NCRT would benefit the most from additional chemotherapy following surgery. The prognosis of rectal cancer is stage dependent, and 2 major analyses question whether T1/2 N1 and T3 N0 patients benefit from NCRT. Application of the results from these studies is hindered by imperfections in staging. Future improvement in patient selection might result from biologic analysis of tumor sensitivity. NCRT might be improved with the use of oral fluoropyrimidines and perhaps the addition of a second agent such as oxaliplatin, irinotecan, or cetuximab. Improvements in radiation, such as the use of more conformal techniques, might decrease the toxicity of therapy. Given the success of NCRT in improving local control, distant metastasis now predominates as the cause of treatment failure, and larger gains will likely be made from improvements in adjuvant chemotherapy.

Oxaliplatin plus irinotecan compared with irinotecan alone as second-line treatment after single-agent fluoropyrimidine therapy for metastatic colorectal carcinoma.

UNLABELLED: PURPOSE To determine whether irinotecan plus oxaliplatin (IROX) is superior to irinotecan alone in patients with metastatic colorectal cancer (CRC) previously treated with single-agent fluoropyrimidines. PATIENTS AND METHODS A phase III, randomized, open-label, multicenter study of patients with metastatic or recurrent CRC that had progressed or recurred during or after adjuvant or first-line fluoropyrimidines (fluorouracil/leucovorin or capecitabine, the latter only for metastatic CRC). Patients received IROX (irinotecan 200 mg/m(2) plus oxaliplatin 85 mg/m(2)) or irinotecan alone (350 mg/m(2)) every 3 weeks. RESULTS: At the data cutoff (when 447 of 628 randomly assigned patients had died), median overall survival was 13.4 months (95% CI, 12.4 to 14.7 months) and 11.1 month (95% CI, 10.0 to 12.7 months) in the IROX and irinotecan groups, respectively (hazard ratio = 0.78; 95% CI, 0.65 to 0.94; P = .0072). Overall response rate (22% v 7%, respectively; P < .0001), median time to progression (5.3 v 2.8 months, respectively; P < .0001), and improvement in tumor-related symptoms (32% v 19%, respectively; P = .0072) were also improved with IROX as compared with irinotecan. With the exception of granulocytopenia (25% v 13%), diarrhea (28% v 23%), and sensory disturbances (5% v 0%), grade 3 to 4 toxicities were comparable between the IROX and irinotecan groups, respectively. CONCLUSION IROX is an effective treatment for metastatic CRC that has progressed after first-line fluoropyrimidine therapy. IROX improves efficacy compared with irinotecan alone, providing an additional option in the postadjuvant or second-line treatment setting for patients who experience treatment failure with single-agent fluoropyrimidine therapy.

Phase I study of preoperative radiation therapy with concurrent infusional 5-fluorouracil and oxaliplatin followed by surgery and postoperative 5-fluorouracil plus leucovorin for T3/T4 rectal adenocarcinoma: ECOG E1297.

PURPOSE: Oxaliplatin is a platinum analog and radiosensitizer active in colorectal cancer. We performed a Phase I trial to test the safety and preliminary efficacy of adding oxaliplatin to standard preoperative chemoradiation therapy for rectal cancer. METHODS AND MATERIALS: Eligible patients had T3 to T4 rectal adenocarcinoma. Patients received standard-dose radiation (50.4 Gy for 5.5 weeks) with concurrent infused 5-fluorouracil (5-FU) at 200 mg/m2 per day, 7 days per week. Oxaliplatin was given three times at 14-day intervals at 55, 70, or 85 mg/m2 during the 5.5-week radiation period, before resection. Adjuvant therapy consisted of four cycles of 5-FU (500 mg/m2 per week) with leucovorin (500 mg/m2 per week) given every 6 weeks. The main goals were to identify the maximum tolerated dose of oxaliplatin and the dose-limiting toxicities when given with 5-FU and RT. Secondary goals were to determine resectability, pathologic response, sphincter preservation, and overall survival rates. RESULTS: Twenty-one patients were enrolled, 5 at the 55 mg/m2 oxaliplatin dose level, 5 at 70 mg/m2, and 11 at 85 mg/m2. All patients were able to complete the preoperative chemoradiation regimen with no dose adjustments. No dose-limiting toxicities or differences in the type or extent of toxicity were noted among the groups. Nineteen patients underwent surgery (three abdominopelvic resections and 16 low anterior resections), for an 84% sphincter preservation rate. The pathologic complete response rate was 26% (5 patients), and minimal microscopic residual tumor was found in 21% (4 additional patients). CONCLUSIONS: Oxaliplatin was well tolerated at 85 mg/m2 given every 2 weeks in combination with standard preoperative chemoradiation for rectal cancer. The rates of major pathologic response and sphincter preservation are promising.

Potential regional differences for the tolerability profiles of fluoropyrimidines.

PURPOSE: We conducted a retrospective analysis of safety data from randomized, single-agent fluoropyrimidine clinical trials (bolus fluorouracil/leucovorin [FU/LV] and capecitabine) to test the hypothesis that there are regional differences in fluoropyrimidine tolerability. METHODS: Treatment-related safety data from three phase III clinical studies were analyzed by multivariate analysis: two comparing capecitabine with bolus FU/LV in metastatic colorectal cancer (MCRC) and one comparing capecitabine plus oxaliplatin (XELOX) with bolus FU/LV as adjuvant treatment for colon cancer. The United States (US) was compared with non-US countries (all three studies) and with the rest of the world and East Asia (adjuvant study). RESULTS: In the MCRC studies (n = 1,189), more grade 3/4 adverse events (AEs; relative risk [RR], 1.77), dose reductions (RR, 1.72), and discontinuations (RR, 1.83) were reported in US versus non-US patients. Likewise, in the adjuvant colon cancer study (n = 1,864), more grade 3/4 AEs (RR, 1.47) and discontinuations (RR, 2.09) were reported in US versus non-US patients. After further dividing non-US patients into those in East Asia and the rest of the world, differential RRs for related grade 3/4 AEs, grade 4 AEs, and serious AEs were again observed, with East Asian patients having the lowest and US patients the highest RR. CONCLUSION: Regional differences exist in the tolerability profiles of fluoropyrimidines. More treatment-related toxicity was reported in the US compared with the rest of the world for bolus FU/LV and capecitabine in first-line MCRC and adjuvant colon cancer. In the adjuvant setting, a range of fluoropyrimidine tolerability was observed, with East Asian patients having the lowest, and US patients the highest, RR.

Survival following recurrence in stage II and III colon cancer: findings from the ACCENT data set.

PURPOSE: This study was undertaken to examine five possible prognostic factors in patients with recurrent stage II and III colon cancer: time from randomization on an adjuvant therapy clinical trial to tumor recurrence (< 1 year, 1 to 2 years, 2 to 3 years, 3 to 4 years, > 4 years), initial stage (II v III), initial adjuvant treatment (fluorouracil [FU]-based v surgery alone), the era in which the patient entered an adjuvant therapy clinical trial (1978 to 1985, 1986 to 1992, 1993 to 1999), and patient age at recurrence. METHODS: The Adjuvant Colon Cancer End Points (ACCENT) data set was analyzed using univariate and multivariate Cox proportional hazards models, stratified by study. RESULTS: 5,722 (32.9%) of 17,381 patients experienced recurrence. Median survival following recurrence was 13.3 months. Time from randomization to recurrence was highly prognostic of survival following recurrence (P < .0001). Longer survival following recurrence was seen in patients with initial stage II versus III disease (P < .0001; 14.3% 6-year overall survival after recurrence in initial stage II patients), patients entered more recently onto trials (P < .0001), and patients initially treated with surgery alone versus FU adjuvant treatment (P = .0005). All relationships were maintained in multivariate models. CONCLUSION: Time from initial treatment to recurrence and initial stage are important prognostic factors in patients with recurrent colon cancer. Survival following recurrence increased modestly from 1978 to 1999. Patients who had a recurrence following adjuvant therapy had poorer prognosis than those who progressed after surgery alone. These prognostic factors may be useful for clinical trial design and treatment decisions in patients with recurrent colon cancer.

Phase III trial of capecitabine plus oxaliplatin as adjuvant therapy for stage III colon cancer: a planned safety analysis in 1,864 patients.

PURPOSE: To report the results of a planned safety analysis from a phase III trial comparing capecitabine plus oxaliplatin (XELOX) with bolus fluorouracil/leucovorin (FU/LV) as adjuvant therapy for stage III colon cancer. PATIENTS AND METHODS: Patients with stage III colon carcinoma were randomly assigned to receive either XELOX (intravenous oxaliplatin plus oral capecitabine; 3-week cycle for eight cycles) or standard intravenous bolus FU/LV administered as the Mayo Clinic (Mayo; Rochester, MN) or Roswell Park (RP; Buffalo, NY) regimen for a similar length of time. A total of 1,886 patients were randomly assigned. RESULTS: The safety population comprised 1,864 patients, of whom 938 received XELOX and 926 received FU/LV. Most treatment-related adverse events (AEs) occurred at similar rates in both treatment arms. However, patients receiving XELOX experienced less all-grade diarrhea, alopecia, and more neurosensory toxicity, vomiting, and hand-foot syndrome than those patients receiving FU/LV. Compared with Mayo, XELOX showed fewer grade 3/4 hematologic AE and more grade 3/4 gastrointestinal AE. Compared with RP, XELOX showed less grade 3/4 gastrointestinal AE and more grade 3/4 hematologic AE. As expected grade 3/4 neurosensory toxicity and grade 3 hand-foot syndrome were higher with XELOX. Treatment-related mortality within 28 days from the last study dose was 0.6% in the XELOX group and 0.6% in the FU/LV group. CONCLUSION: XELOX has a manageable tolerability profile in the adjuvant setting. Efficacy data will be available within the next 24 months.

Phase III trial of fluorouracil-based chemotherapy regimens plus radiotherapy in postoperative adjuvant rectal cancer: GI INT 0144.

PURPOSE: Adjuvant chemoradiotherapy after or before resection of high-risk rectal cancer improves overall survival (OS) and pelvic control. We studied three postoperative fluorouracil (FU) radiochemotherapy regimens. PATIENTS AND METHODS: After resection of T3-4, N0, M0 or T1-4, N1, 2M0 rectal adenocarcinoma, 1,917 patients were randomly assigned to arm 1, with bolus FU in two 5-day cycles every 28 days before and after radiotherapy (XRT) plus FU via protracted venous infusion (PVI) 225 mg/m2/d during XRT; arm 2 (PVI-only arm), with PVI 42 days before and 56 days after XRT + PVI; or arm 3 (bolus-only arm), with bolus FU + leucovorin (LV) in two 5-day cycles before and after XRT, plus bolus FU + LV (levamisole was administered each cycle before and after XRT). Patients were stratified by operation type, T and N stage, and time from surgery. RESULTS: Median follow-up was 5.7 years. Lethal toxicity was less than 1%, with grade 3 to 4 hematologic toxicity in 49% to 55% of the bolus arms versus 4% in the PVI arm. No disease-free survival (DFS) or OS difference was detected (3-year DFS, 67% to 69% and 3-year OS, 81% to 83% in all arms). Locoregional failure (LRF) at first relapse was 8% in arm 1, 4.6% in arm 2, and 7% in arm 3. LRF in T1-2, N1-2, and T3, N0-2 primaries who received low anterior resection (those most suitable for primary resection) was 5% in arm 1, 3% in arm 2, and 5% in arm 3. CONCLUSION: All arms provide similar relapse-free survival and OS, with different toxicity profiles and central catheter requirements. LRF with postoperative therapy is low, justifying initial resection for T1-2, N0-2 and T3, and N0-2 anterior resection candidates.

Phase III study of fluorouracil, leucovorin, and levamisole in high-risk stage II and III colon cancer: final report of Intergroup 0089.

PURPOSE: In 1990, fluorouracil (FU) plus levamisole for 1 year became standard adjuvant treatment for patients with high-risk stages II and III colon cancer. Intergroup (INT) 0089 assessed the relative contributions of leucovorin and levamisole in such patients. PATIENTS AND METHODS: From 1988 to 1992, 3,794 patients were randomly assigned. Experimental treatment consisted of one of three chemotherapy regimens: the low-dose leucovorin plus FU (Mayo Clinic; LDLV) regimen, the high-dose leucovorin plus FU (Roswell Park; HDLV) regimen, and the low-dose leucovorin plus levamisole plus FU (LDLV plus LEV) regimen, each administered for 30 to 32 weeks. The control arm was levamisole plus FU (LEV) for 1 year. RESULTS: After a median follow-up of 10 years, of 3,561 eligible patients, 1,691 (47%) have died and 1,330 (37%) have experienced disease recurrence; 137 (10%) of those experiencing recurrence are still alive. A total of 481 patients (13%) died without evidence of recurrence, and 1,723 (48%) are alive and disease free. Although there were toxicity differences among the four arms, none was statistically superior in disease-free or overall survival. CONCLUSION: The 6- to 8-month regimens of LDLV and HDLV without levamisole used in this trial, rather than the previous standard regimen of 12 months of LEV, have become widely used. INT-0089 has long-term follow-up of the largest clinical trial of patients with high-risk colon cancer, documenting not only the durability of the treatment effects, but also the natural history of patients with high-risk colon cancer, and analyses of treatment based on age, race, and comorbid conditions such as obesity, diabetes, and second primary cancers.