Clinical trial to assess the relative efficacy of fluorouracil and leucovorin, fluorouracil and levamisole, and fluorouracil, leucovorin, and levamisole in patients with Dukes' B and C carcinoma of the colon: results from National Surgical Adjuvant Breast and Bowel Project C-04

Randomized clinical trials in colon cancer

Surgery remains the mainstay of treatment for colon cancer and surgical resection alone results in 5-year survival in more than 60% of patients. However, the use of fluorouracil (5-FU)-based adjuvant chemotherapy for patients at high risk of recurrence further prolongs disease-free survival and has become the standard of care. New areas of research focus on decreasing the surgical trauma with minimally invasive approaches, improving the surgical staging of patients with colon cancer, and improving adjuvant treatment regimens. We review those randomized controlled trials that have most impacted the clinical management of patients with colon cancer in 2009.

Adjuvant chemotherapy for stages II, III and IV of colon cancer

Colorectal cancer is the third most frequent malignant neoplasm in Western countries. After complete resection, 5-year overall survival varies according to the initial stage. Adjuvant chemotherapy (CT) is indicated in patients with colon cancer at high-risk stage II, stage III and after complete resection of metastases. 5-Fluorouracil (5FU), alone or modulated with levamisol or leucovorin (LV), oral fluoropyrimidines, raltitrexed, irinotecan and oxaliplatin have been studied as adjuvant therapy for colon cancer. Nowadays, oxaliplatin-based regimens, FOLFOX or FLOX, are considered as the standard adjuvant CT. If there are contraindications for oxaliplatin, the best alternatives are capecitabine or continuous infusion of 5FU/LV. The role of monoclonal antibodies, cetuximab and bevacizumab, combined with oxaliplatin/fluoropyrimidine-based CT is under investigation in clinical trials. This article reviews the state of the art and the future perspectives of adjuvant therapy in colon cancer. Prognostic and predictive factors are also commented on.

Advances in the treatment of metastatic colorectal cancer

The treatment of metastatic colorectal cancer has undergone major advances yielding significant improvements in survival over the past decade. These advances have evolved due to the benefits of combination chemotherapy and the incorporation of biologic therapy. However, as we struggle to provide optimum care while sparing patients ineffective therapy and undue cost, the importance of tailored therapy to maximize benefit will become increasingly important. This article reviews the major advances in the treatment of patients with metastatic colorectal cancer and the burgeoning developments in individualized therapy.

Efficacy of postoperative UFT (Tegafur/Uracil) plus PSK therapies in elderly patients with resected colorectal cancer

To establish the sufficient therapy for elderly colorectal cancer patients, we retrospectively compared postoperative Tegafur/Uracil (UFT; Taiho Pharmaceutical Co., Ltd., Tokyo, Japan) and UFT plus protein-bound polysaccharide kureha (PSK) therapies in elderly patients with resected colorectal cancer. A total of 63 patients were collected; 39 patients were administered only with UFT (control group) and 24 patients were treated with UFT+PSK (PSK group). There were no differences in patient background, surgical outcomes, and drug compliance between the two groups. The 3-year relapse-free survival rate was 47.8% in the control group and 76.2% in the PSK group (p = 0.041). The 3-year overall survival (OS) rate was 52.8% in the control group and 80.8% in the PSK group (p = 0.0498). By subset analysis, in the patients whose tumor location was the colon (p = 0.016) and whose preoperative lymphocyte percentage was below 18.7% (p = 0.017), RFS was significantly better in the PSK group. Adverse drug reactions were rarely observed. All the adverse reactions were grade 2 or below, with no severe reactions. The present retrospective study suggests a possible efficacy of postoperative adjuvant therapy with UFT plus PSK in elderly patients over 70 years of age with resected colorectal cancer.

Final results of a randomised phase III study on adjuvant chemotherapy with 5 FU and levamisol in colon and rectum cancer stage II and III by the Norwegian Gastrointestinal Cancer Group

BACKGROUND

The recommendation of adjuvant chemotherapy for colon cancer with lymph node metastases, based on two studies from USA, was reluctantly accepted by Norwegian medical doctors. It was therefore decided to assess the role of adjuvant therapy with 5fluorouracil (5-FU) combined with levamisole (Lev) in a confirmatory randomised study.

MATERIAL AND METHODS

Four hundred and twenty five patients with operable colon and rectum cancer, Stage II and III (Dukes' stage B and C), were from January 1993 to October 1996, included in a randomised multicentre trial in Norway. The age limits were 18-75 years. Therapy started with a loading course of bolus i.v. 5-FU (450 mg/m(2)) daily for 5 days and p.o. doses of Lev (50 mg x 3) for 3 days. From day 28 a weekly i.v. 5-FU dose (450 mg/m(2)) were administered for 48 weeks. From day 28 also p.o. doses of Lev (50 mg x 3) for 3 days were given every 14 days. In total 214 patients were randomised to 5FU/Lev and 211 were included in the control group with surgery alone. Some did not comply with the inclusion and exclusion criteria, thus leaving 206 evaluable patients in each group.

RESULTS

There was no significant survival difference between the two groups at 5 years: Disease-free survival (DFS) was 73% after chemotherapy, 68% (p=0.24) in the control group, and corresponding cancer specific survival (CSS) 75% and 71%, respectively (p=0.69). There was no difference between the two groups when analysed for colon and rectum separately. However, the subgroup of colon cancer with stage III exhibited a statistically significant difference both for DFS, 58% vs. 37% (p=0.012) and CSS, 65% vs. 47% (p=0.032) in favour of adjuvant chemotherapy. The benefit was further statistically significant for women but not for men. Toxicity was generally mild and acceptable with no drug related fatalities.

CONCLUSIONS

Colon cancer patients with lymph node metastases benefit from adjuvant chemotherapy with 5-FU/Lev with acceptable toxicity. In a subgroup analysis females did better than males. Rectal cancer does not benefit from this regimen.

Etiology of delays in the initiation of adjuvant chemotherapy and their impact on outcomes for Stage II and III rectal cancer

PURPOSE

This study was designed to evaluate the role of access to care and postsurgical recovery on delays in adjuvant chemotherapy for rectal cancer.

METHODS

Using data from the linked Surveillance, Epidemiology, and End Results-Medicare database, we analyzed patients with Stage II or III rectal cancer who received adjuvant chemotherapy after curative rectal cancer surgery between 1991 and 2002. Logistic and Cox regressions were performed to assess determinants of adjuvant chemotherapy delays and outcomes in two cohorts: patients with access to medical oncology care because of prior neoadjuvant chemotherapy (Group A) and patients without such access (Group B). Length of postoperative hospital stay served as the main proxy for postsurgical recovery.

RESULTS

A total of 442 and 5,617 patients were included in Groups A and B, respectively. The median interval between surgery and adjuvant chemotherapy was 46 days in Group A and 42 days in Group B. Although 17 percent and 11 percent of patients in Groups A and B, respectively, waited three or more months for adjuvant chemotherapy, median overall survival was worse in this subset than in those who waited less than 3 months (54 vs. 76 months, P < 0.01). Postoperative hospital stay independently predicted for adjuvant chemotherapy delay in both groups. Disparities in delays were seen only in Group B, such that patients who were older or black had greater odds of an adjuvant chemotherapy delay (for both, P < 0.05).

CONCLUSION

Advanced age and black race contribute to adjuvant chemotherapy delays and inferior outcomes, but postoperative recovery is the more important driver.

Randomized phase III trial comparing biweekly infusional fluorouracil/leucovorin alone or with irinotecan in the adjuvant treatment of stage III colon cancer: PETACC-3

PURPOSE The primary objective of this randomized, multicenter, phase III trial was to investigate whether the addition of irinotecan to the de Gramont infusional fluorouracil (FU)/leucovorin (LV) adjuvant regimen (LV5FU2) would improve disease-free survival (DFS) in patients with stage III colon cancer. PATIENTS AND METHODS After curatively intentioned surgery, patients with stage II and III colon cancer were randomly allocated surgery to receive LV5FU2 (LV 200 mg/m(2) as a 2-hour infusion, followed by FU; as a 400 mg/m(2) bolus and then a 600 mg/m(2) continuous infusion over 22 hours, days 1 and 2, every 2 weeks for 12 cycles: de Gramont regimen) with or without irinotecan (180 mg/m(2) as a 30- to 90-minute infusion, day 1, every 2 weeks). In total, 260 (7.9%) of 3,278 patients received an alternative high-dose infusional FU/LV regimen (Arbeitsgemeinschaft Internische Onkologie regimen) with or without irinotecan. Results The principal efficacy analysis was based on 2,094 treated patients with stage III disease, randomly allocated in the LV5FU2 strata. After a median follow-up of 66.3 months, the 5-year DFS rate was 56.7% with irinotecan/LV5FU2 and 54.3% with LV5FU2 alone (primary end point: log-rank P = .106). Combining irinotecan with LV5FU2 did not significantly improve overall survival in this patient group compared with LV5FU2 alone (5-year rate 73.6% v 71.3%, respectively; log-rank P = .094). The addition of irinotecan to LV5FU2 was associated with an increased incidence of grade 3 to 4 GI events and neutropenia. CONCLUSION Irinotecan added to LV5FU2 as adjuvant therapy did not confer a statistically significant improvement in DFS or overall survival in patients with stage III colon cancer compared with LV5FU2 alone.

Improved overall survival with oxaliplatin, fluorouracil, and leucovorin as adjuvant treatment in stage II or III colon cancer in the MOSAIC trial

PURPOSE Three-year disease-free survival (DFS) was significantly improved in patients who had undergone resection with curative intent for stage II or III colon cancer who received bolus plus continuous-infusion fluorouracil plus leucovorin (LV5FU2) with the addition of oxaliplatin (FOLFOX4). Final results of the study, including 6-year overall survival (OS) and 5-year updated DFS, are reported. PATIENTS AND METHODS A total of 2,246 patients were randomly assigned to receive LV5FU2 or FOLFOX4 for 6 months. The primary end point was DFS. Secondary end points were OS and safety. Results Five-year DFS rates were 73.3% and 67.4% in the FOLFOX4 and LV5FU2 groups, respectively (hazard ratio [HR] = 0.80; 95% CI, 0.68 to 0.93; P = .003). Six-year OS rates were 78.5% and 76.0% in the FOLFOX4 and LV5FU2 groups, respectively (HR = 0.84; 95% CI, 0.71 to 1.00; P = .046); corresponding 6-year OS rates for patients with stage III disease were 72.9% and 68.7%, respectively (HR = 0.80; 95% CI, 0.65 to 0.97; P = .023). No difference in OS was seen in the stage II population. The incidence of second noncolorectal cancers was 5.5% and 6.1% in the FOLFOX4 and LV5FU2 groups, respectively. Among patients receiving oxaliplatin, the frequency of grade 3 peripheral sensory neuropathy was 1.3% 12 months after treatment and 0.7% at 48 months. CONCLUSION Adding oxaliplatin to LV5FU2 significantly improved 5-year DFS and 6-year OS in the adjuvant treatment of stage II or III colon cancer and should be considered after surgery for patients with stage III disease.

Evidence for cure by adjuvant therapy in colon cancer: observations based on individual patient data from 20,898 patients on 18 randomized trials

PURPOSE

Limited data are available on the time course of treatment failures (recurrence and/or death), the nature and duration of adjuvant treatment benefit, and long-term recurrence rates in patients with resected stage II and III colon cancer.

METHODS

The data set assembled by the Adjuvant Colon Cancer Endpoints Group, a collection of individual patient data from 18 trials and more than 20,800 patients testing fluorouracil-based adjuvant therapy in patients with stage II or III colon cancer, was analyzed.

RESULTS

A significant overall survival (OS) benefit of adjuvant therapy was consistent over the 8-year follow-up period. The risk of recurrence in patients treated with adjuvant chemotherapy never exceeds that of control patients, signifying that adjuvant therapy cures some patients, as opposed to delaying recurrence. After 5 years, recurrence rates were less than 1.5% per year, and after 8 years, they were less than 0.5% per year. Significant disease-free survival (DFS) benefit from adjuvant chemotherapy was observed in the first 2 years. After 2 years, DFS rates in treated and control patients were not significantly different, and after 4 years, no trend toward benefit was demonstrated. This benefit was primarily driven by patients with stage III disease.

CONCLUSION

Adjuvant chemotherapy provides significant DFS benefit, primarily by reducing the recurrence rate, within the first 2 years of adjuvant therapy with some benefit in years 3 to 4, translating into long-term OS benefit. This reflects the curative role of chemotherapy in the adjuvant setting. After 5 years, recurrence rates in patients treated on clinical trials are low, and after 8 years, they are minimal; thus, long-term follow-up for recurrence is of little value.

Elevated preoperative serum carcinoembrionic antigen level may be an effective indicator for needing adjuvant chemotherapy after potentially curative resection of stage II colon cancer

BACKGROUND

To determine the prognostic factors and to rationalize adjuvant therapy, the clinicopathologic data of patients with a stage II colon cancer were analyzed retrospectively.

PATIENTS AND METHODS

A total of 392 patients underwent potentially curative resection at the Kurume University Hospital between 1982 and 2005. Postoperative adjuvant chemotherapy using oral fluoropyrimidines was administered in 163 patients, and the other 229 patients underwent surgery alone. Univariate and multivariate analyses for prognostic factors were carried out.

RESULTS

Invasive type in gross features, elevated preoperative CEA level, and surgery alone were each an independently significant factor for shorter relapse-free survival, and tumor size <50 mm, invasive type in gross features, elevated preoperative CEA level, and surgery alone were each an independently significant factor for shorter overall survival. The relapse-free survival rate and overall survival rate in the patients who received postoperative adjuvant chemotherapy were significantly higher than those in the patients treated with surgery alone even after stratifying to the preoperative CEA level.

CONCLUSION

Patients with an elevated preoperative CEA may be candidates for adjuvant chemotherapy after curative resection in stage II colon cancer. These findings warrant clinical trials to test out the efficacy of adjuvant chemotherapy in stage II colon cancer with an elevated preoperative CEA.

The half century of clinical trials of the National Surgical Adjuvant Breast And Bowel Project

The supplanting of radical mastectomy by simple mastectomy and then by lumpectomy plus radiation, the use of adjuvant therapy to alter the natural course of breast and colorectal cancer, the use of tamoxifen for the prevention of breast cancer, and the dramatic improvement in survival demonstrated with the use of the monoclonal antibody trastuzumab in women with HER2-positive breast cancer are all the direct results of research that has been carried out over the past 50 years by the National Surgical Adjuvant Breast and Bowel Project (NSABP). This National Cancer Institute-supported clinical cooperative trials group based in Pittsburgh, PA, currently has 200 member institutions and 700 satellite centers located throughout the United States, Canada, Puerto Rico, and Ireland. The NSABP's mandate is to conduct large randomized phase III trials to evaluate therapies designed to improve the treatment and prevention of breast and colorectal cancer. Over the past half century, the NSABP has entered more than 150,000 patients and participants into clinical studies that have changed the treatment of colorectal cancer and have revolutionized the treatment and prevention of breast cancer.

5-fluorouracil pharmacokinetics predicts disease-free survival in patients administered adjuvant chemotherapy for colorectal cancer

PURPOSE

To evaluate 5-fluorouracil (5-FU) and 5-fluoro-5,6-dihydrouracil (5-FDHU) pharmacokinetics and disease-free survival (DFS) in colorectal cancer patients given 5-FU-based adjuvant chemotherapy within a nonrandomized, retrospective, pharmacokinetic study.

EXPERIMENTAL DESIGN

One hundred fifteen patients including 72 men (median age, 63 years; range, 36-79 years) and 43 women (median age, 60 years; range, 36-73 years) received 6 cycles of l-leucovorin 100 mg/m(2)/day and 5-FU 370 mg/m(2)/day i.v. boluses (5 days every 4 weeks). Individual plasma concentrations of 5-FU and 5-FDHU were determined on day 1 of the first cycle with a validated high performance liquid chromatography method, and the main pharmacokinetic variables were determined. Follow-up of all patients was extended up to 5 years after the end of adjuvant chemotherapy, and DFS was recorded. Univariate and multivariate analyses were conducted to evaluate any correlation among 5-FU pharmacokinetics, clinical and pathologic variables, and DFS.

RESULTS

The area under the time/concentration curve (AUC) of 5-FU was significantly lower in 58 subjects who recurred (7.5 +/- 2.9 h x mg/L) with respect to other patients (9.3 +/- 4.1 h x mg/L). Furthermore, AUC values lower than 8.4 h x mg/L together with lymph node involvement and the interruption of treatment or reduction of doses were identified as risk factors at univariate analysis. The completion of 6 cycles of adjuvant treatment without dosage modifications was the only independent risk factor at multivariate analysis, despite a trend toward significance for 5-FU AUC values (cutoff value, 8.4 hxmg/L) was observed (P = 0.06).

CONCLUSIONS

Pharmacokinetics of 5-FU should be regarded as an important factor for predicting disease recurrence in colorectal cancers.

Does the decision in a validation process of a surrogate endpoint change with level of significance of treatment effect? A proposal on validation of surrogate endpoints

BACKGROUND

In recent years the use of surrogate end points (S) has become an interesting issue. In clinical trials, it is important to get treatment outcomes as early as possible. For this reason there is a need for surrogate endpoints (S) which are measured earlier than the true endpoint (T). However, before a surrogate endpoint can be used it must be validated. For a candidate surrogate endpoint, for example time to recurrence, the validation result may change dramatically between clinical trials. The aim of this study is to show how the validation criterion (R(2)(trial)) proposed by Buyse et al. are influenced by the magnitude of treatment effect with an application using real data.

METHODS

The criterion R(2)(trial) proposed by Buyse et al. (2000) is applied to the four data sets from colon cancer clinical trials (C-01, C-02, C-03 and C-04). Each clinical trial is analyzed separately for treatment effect on survival (true endpoint) and recurrence free survival (surrogate endpoint) and this analysis is done also for each center in each trial. Results are used for standard validation analysis. The centers were grouped by the Wald statistic in 3 equal groups.

RESULTS

Validation criteria R(2)(trial) were 0.641 95% CI (0.432-0.782), 0.223 95% CI (0.008-0.503), 0.761 95% CI (0.550-0.872) and 0.560 95% CI (0.404-0.687) for C-01, C-02, C-03 and C-04 respectively. The R(2)(trial) criteria changed by the Wald statistics observed for the centers used in the validation process. Higher the Wald statistic groups are higher the R(2)(trial) values observed.

CONCLUSION

The recurrence free survival is not a good surrogate for overall survival in clinical trials with non significant treatment effects and moderate for significant treatment effects. This shows that the level of significance of treatment effect should be taken into account in validation process of surrogate endpoints.

The efficacy of adjuvant chemotherapy with 5-fluorouracil in colorectal cancer depends on the mismatch repair status

AIMS

The aim of this study is to evaluate if mismatch repair (MMR) defective colorectal cancer has a different response to adjuvant 5-fluorouracil (5-FU) chemotherapy in a cohort of patients prospectively followed during 5 years.

METHODS

The cohort included 754 surgically treated patients with colorectal cancer. MMR status was diagnosed by MLH1 and MSH2 immunohistochemistry and microsatellite instability analysis. Median follow-up was 49.2 months (range 1-73). At inclusion, 505 patients were diagnosed as TNM II or III stage, analysis of the efficacy of adjuvant chemotherapy was made on this population. Adjuvant chemotherapy was applied to 248 patients (98.2% 5-FU based).

RESULTS

MMR deficiency was found in 76 patients (10.1%). No differences were found in overall survival (log-rank p=0.3) or disease-free survival (log-rank p=0.3) regarding MMR status. Adjuvant chemotherapy improves survival in patients in the II or III stage, but this improvement is only evident in patients with MMR-competent tumours (log-rank p=0.00001). Survival of patients with MMR-defective tumours does not improve with adjuvant chemotherapy (log-rank p=0.7). A multivariate analysis showed an independent effect of the interaction between MMR status and adjuvant chemotherapy (Hazard ratio 2.04; 95% confidence interval: 1.42-2.93).

CONCLUSION

In a cohort of colorectal cancer patients, those with MMR-deficient tumours seem not to benefit from 5-FU-based chemotherapy.

Epidemiology and management options for colorectal cancer in children

Colorectal carcinoma (CRC), although primarily a disease of adulthood, accounts for 2% of malignancies in adolescents and has been reported in children as young as 9 months of age. Our knowledge of CRC in pediatrics is based on a handful of case series and case reports. Apart from one small clinical trial, there has been a lack of prospective clinical studies in this age group. Based on these published reports, most CRC in children is sporadic, but it can also arise in the setting of predisposing conditions, such as gastrointestinal polyposis syndromes, nonpolyposis familial cancer syndromes, and inflammatory bowel disease. Despite some similarities to adult disease, CRC in childhood may be intrinsically different biologically, because it differs from adult-onset CRC in several respects. Childhood CRC tends to be diagnosed at an advanced stage, is largely of mucinous histology, and (probably because of these features) tends to have a poorer outcome. As a result of its rarity in children and the lack of prospective pediatric studies, recommendations for therapy are primarily extrapolated from adult clinical trials. A review of pediatric case series in the English literature emphasizes the prognostic significance of stage of disease, as well as extent of surgical resection. As in adults, early detection is critical in an effort to capture the disease at less advanced stages. Complete surgical resection with aggressive lymph node dissection is essential for cure, and neoadjuvant chemotherapy may be used in an effort to render unresectable lesions resectable. Active agents in adults with CRC include fluorouracil, folinic acid (leucovorin), oxaliplatin, and irinotecan. Furthermore, newer targeted therapeutic agents, such as bevacizumab and cetuximab, have added additional efficacy to the standard chemotherapy backbone. Collaborative multi-institutional pediatric clinical trials are needed to evaluate the prognosis, optimal treatment response, and the basic biology of childhood onset CRC.

Severe sequence-specific toxicity when capecitabine is given after Fluorouracil and leucovorin

PURPOSE

Options for single-agent fluoropyrimidine adjuvant therapy after bowel cancer resection include intravenous fluorouracil with leucovorin (FU/LV) or oral capecitabine. These treatments have similar efficacy but differ in convenience and toxicity. We therefore wished to compare their overall acceptability to patients.

PATIENTS AND METHODS

Patients scheduled for adjuvant single-agent fluoropyrimidine therapy were randomly assigned to receive once-weekly FU/LV (425 mg/m(2) FU, 45 mg LV) for 6 weeks, followed by two 3-week cycles of capecitabine (1,250 mg/m(2) twice daily, days 1 through 14), or the same treatments but in reverse order. After 12 weeks, the patients were asked which treatment they preferred, and received the preferred treatment for an additional 12 weeks. The primary end point was patient preference.

RESULTS

After 40 of the planned 74 patients had been randomly assigned, real-time adverse event monitoring led to early trial closure because of excess sequence-specific toxicity. Eleven of 14 patients (79%) receiving capecitabine as their second treatment experienced grade >/= 3 toxicity. This compared with five of 18 patients (28%) receiving capecitabine as the first treatment, and no patients receiving FU/LV as the first treatment (zero of 16) or the second treatment (zero of 12). Similar imbalances were seen in the proportion of patients requiring interruption of treatment.

CONCLUSION

In chemotherapy-naïve patients, capecitabine produced more toxicity than FU/LV, but at levels in line with previously reported data. However, treatment with capecitabine after FU/LV caused markedly increased toxicity, indicating a sequence-specific interaction. The mechanism has not been determined, but interaction with intracellularly retained folate after FU/LV therapy is a possibility. Oncologists need to be aware of this risk if considering crossing patients over from FU/LV to capecitabine-based regimens.

American Society of Clinical Oncology/National Comprehensive Cancer Network Quality Measures

PURPOSE

The National Cancer Policy Board recommended the creation of quality measures and a national reporting system in 1999. Representatives from the American Society of Clinical Oncology (ASCO) and the National Comprehensive Cancer Network (NCCN) collaborated to create metrics suitable for national performance measurement.

METHODS

Content and methodology experts nominated by ASCO and NCCN met to select and refine metrics for breast, colon, and rectal cancer based on National Initiative for Cancer Care Quality and NCCN measures and NCCN and ASCO guidelines. Measures were selected based on their impact on disease free and overall survival, the degree to which opportunities for improvement exist, and the feasibility of data collection.

RESULTS

Three breast cancer measures and four colorectal cancer measures were chosen. Measures for breast cancer included adjuvant hormone therapy for hormone receptor-positive tumors, chemotherapy for hormone receptor-negative cancer, and radiation after lumpectomy. Colorectal measures included adjuvant radiation and chemotherapy for rectal cancer, and adjuvant chemotherapy for colon cancer. All but one were recommended as accountability measures and one for quality improvement (removal and examination of 12 or more lymph nodes in colon cancer). Specifications were developed for each measure using tumor registries as the data source.

CONCLUSION

ASCO/NCCN measures can be implemented by health systems, provider groups or payors for improvement or accountability using local tumor registries to furnish data on staging and treatment.

Early distant relapse after optimal local control in locally advanced rectal cancer

We present a case of locally advanced rectal cancer with initial optimal local control after neoadjuvant concurrent chemoradiotherapy followed by surgery; early liver recurrence then occurred and was treated again with curative intent with neoadjuvant combination chemotherapy followed by liver surgery. We reflect on this difficult problem and discuss relevant topics to this case report.

Adjuvant chemotherapy for stage III colon cancer: do physicians agree about the importance of patient age and comorbidity?

PURPOSE

We surveyed cancer physicians to understand how patients' age and comorbidity influence adjuvant chemotherapy recommendations and whether physician or practice characteristics also affect these recommendations.

METHODS

National survey of surgeons and medical oncologists caring for patients with colorectal cancer regarding whether they would recommend adjuvant chemotherapy for hypothetical patients with stage III colon cancer who varied by age (55 v 80 years) and comorbid illness (none, moderate, severe congestive heart failure [CHF]). Repeated measures logistic regression was used to assess the influence of patient, physician, and practice characteristics on chemotherapy recommendations.

RESULTS

Of 1,096 physicians, nearly all recommended chemotherapy for patients who were 55 years old with no comorbidity (99.0%), 55-years old with moderate CHF (88.6%), or 80 years old with no comorbidity (92.6%); many fewer recommended chemotherapy for 55-year-old patients with severe CHF (24.9%) or 80-year-old patients with moderate (47.2%) or severe (9.0%) CHF (P < .001). Younger physicians (P < .001) were more likely than others to recommend adjuvant chemotherapy overall, although physician factors explained little of the variability in recommendations.

CONCLUSION

Physicians agree with guidelines recommending adjuvant chemotherapy for young, healthy patients with stage III colon cancer but differ widely on recommendations for patients who are older and sicker. Few physician or practice characteristics were associated with recommendations. For older and sicker patients, the individual physicians seen may have a substantial impact on the likelihood of receiving chemotherapy. Understanding better the sources of variation not explained by patients' clinical characteristics may allow improved tailoring of therapy to patients most likely to benefit.

Development of a clinically feasible molecular assay to predict recurrence of stage II colon cancer

The 5-year survival rate for patients with Stage II colon cancer is approximately 75%. However, there is no clinical test available to identify the 25% of patients at high risk of recurrence. We have previously identified a 23-gene signature that predicts individual risk for recurrence. The present study tested this gene signature in an independent group of 123 Stage II patients, and the 23-gene signature was highly informative in identifying patients with distant recurrence in both univariate (hazard ratio [HR] 2.51) and multivariate analyses (HR, 2.40). The composition of this representative patient group also allowed us to refine the 23-gene signature to a 7-gene signature that exhibited a similar prognostic power in both univariate (HR, 2.77) and multivariate analyses (HR, 2.87). Furthermore, we developed this prognostic signature into a clinically feasible test with real-time quantitative PCR using standard fixed paraffin-embedded tumor tissues. When a 110-patient cohort was evaluated with the PCR assay, the 7-gene signature, demonstrated to be a strong prognostic factor in both univariate (HR, 6.89) and multivariate analyses (HR, 14.2). These results clearly show the prognostic value of the predefined gene signature for Stage II colon cancer patients. The ability to identify colon cancer patients with an unfavorable outcome may help patients at high risk for recurrence to seek more aggressive therapy.

Progress and challenges in the adjuvant treatment of stage II and III colon cancers

Whereas the benefit of adjuvant 5-fluorouracil and leucovorin have been well established in resected stage III colon cancer, a significant benefit for patients with stage II disease has been more difficult to demonstrate. More recently, oxaliplatin-based chemotherapy with regimens such as oxaplatin plus 5-fluorouracil/leucovorin have been shown to improve disease-free and overall survival in these stage III patients. This review will discuss the development of adjuvant chemotherapy in colon cancer, focusing on recent progress and particular topical issues related to its use in this disease, such as the use of surrogate end points for overall survival in contemporary clinical trials.

Prognostic and predictive value of thymidylate synthase expression in colon cancer

Thymidylate synthase (TS) is an enzyme responsible for DNA synthesis. Its competitive inhibition constitutes the major mechanism of the antitumor effect of 5-fluorouracil (5-FU) therapy, which significantly improves the survival rate of colon cancer patients. The aim of our study was to examine the clinical importance of TS expression in colon cancer patients and to correlate its expression with various clinicopathological parameters, tumor proliferative capacity, cell cycle-related molecules' expression and patients' survival. Of the 71 colon cancer patients studied, 51 (71.8%) tested positive for TS, with the positive result being statistically significantly correlated with patients' gender (P = 0.012), tumor histological grade (P = 0.032), vascular invasion (P = 0.017) and the expression of cyclin E, pRb and p16 (P = 0.042, P = 0.001 and P = 0.001, respectively). The overall 5-year survival rate was 40% for TS-positive patients and 68.6% for TS-negative ones (P = 0.0134); in patients aged >70 years, this was 30 and 77.8%, respectively (P = 0.0008). In a multivariate analysis of survival, TS expression proved to be of prognostic significance (P = 0.0174). Our findings support evidence for the clinical importance of TS expression in colon cancer patients and define it as an independent prognostic risk factor.

Systemic treatment of colorectal cancer

Colorectal cancer is the fourth most common noncutaneous malignancy in the United States and the second most frequent cause of cancer-related death. Over the past 12 years, significant progress has been made in the systemic treatment of this malignant condition. Six new chemotherapeutic agents have been introduced, increasing median overall survival for patients with metastatic colorectal cancer from less than 9 months with no treatment to approximately 24 months. For patients with stage III (lymph node positive) colon cancer, an overall survival benefit for fluorouracil-based chemotherapy has been firmly established, and recent data have shown further efficacy for the inclusion of oxaliplatin in such adjuvant treatment programs. For patients with stage II colon cancer, the use of adjuvant chemotherapy remains controversial, but may be appropriate in a subset of individuals at higher risk for disease recurrence. Ongoing randomized clinical trials are evaluating how best to combine currently available therapies, while smaller studies are evaluating new agents, with the goal of continued progress in prolonging life among patients with metastatic colorectal cancer and increasing cure rates among those with resectable disease.

FOLFIRI Is Tolerable after Subtotal Colectomy - A Patient with Familial Adenomatous Polyposis Who Developed Advanced Rectal Cancer

A 40-year-old female with familial adenomatous polyposis (FAP) had a subtotal colectomy at 16 years of age. At 39 years, she had low anterior resection due to advanced rectal carcinoma. Thereafter, we administrated per os uracil and tegafur for 9 months. Metastatic rectal carcinoma was detected in the liver (S8) by computed tomography (CT). 2-[(18)F]-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) data did not show any other metastasis. This report presents a first case of a patient undergoing subtotal colectomy administered FOLFIRI (CPT-11 180 mg/m² as a 90-minute infusion on day 1; leucovorin 400 mg/m² as a 2-hour infusion during CPT-11, immediately followed by 5-FU bolus 400 mg/m² and 46-hour continuous infusion of 2,400 mg/m² every 2 weeks). This regimen was administered without grade 3 or 4 of any adverse reaction for 6 months, although there was a possibility that this patient with subtotal colectomy may have the cause for severe diarrhea. Further investigations are needed to assess the safety in clinical trials of FOLFIRI regimen for patients with subtotal colectomy.

Adjuvant chemotherapy versus observation in patients with colorectal cancer: a randomised study

BACKGROUND

The aim of the QUASAR trial was to determine the size and duration of any survival benefit from adjuvant chemotherapy for patients with colorectal cancer at low risk of recurrence, for whom the indication for such treatment is unclear.

METHODS

After apparently curative resections of colon or rectal cancer, 3239 patients (2963 [91%] with stage II [node negative] disease, 2291 [71%] with colon cancer, median age 63 [IQR 56-68] years) enrolled between May, 1994, and December, 2003, from 150 centres in 19 countries were randomly assigned to receive chemotherapy with fluorouracil and folinic acid (n=1622) or to observation (with chemotherapy considered on recurrence; n=1617). Chemotherapy was delivered as six 5-day courses every 4 weeks or as 30 once-weekly courses of intravenous fluorouracil (370 mg/m2) with high-dose (175 mg) L-folinic acid or low-dose (25 mg) L-folinic acid. Until 1997, levamisole (12 courses of 450 mg over 3 days repeated every 2 weeks) or placebo was added. After 1997, patients who were assigned to receive chemotherapy were given fluorouracil and low-dose folinic acid only. The primary outcome was all-cause mortality. Analyses were done by intention to treat. This trial is registered with the International Clinical Trial Registry, number ISRCTN82375386.

FINDINGS

At the time of analysis, 61 (3.8%) patients in the chemotherapy group and 50 (3.1%) in the observation group had missing follow-up. After a median follow-up of 5.5 (range 0-10.6) years, there were 311 deaths in the chemotherapy group and 370 in the observation group; the relative risk of death from any cause with chemotherapy versus observation alone was 0.82 (95% CI 0.70-0.95; p=0.008). There were 293 recurrences in the chemotherapy group and 359 in the observation group; the relative risk of recurrence with chemotherapy versus observation alone was 0.78 (0.67-0.91; p=0.001). Treatment efficacy did not differ significantly by tumour site, stage, sex, age, or chemotherapy schedule. Eight (0.5%) patients in the chemotherapy group and four (0.25%) in the observation group died from non-colorectal cancer causes within 30 weeks of randomisation; only one of these deaths was deemed to be possibly chemotherapy related.

INTERPRETATION

Chemotherapy with fluorouracil and folinic acid could improve survival of patients with stage II colorectal cancer, although the absolute improvements are small: assuming 5-year mortality without chemotherapy is 20%, the relative risk of death seen here translates into an absolute improvement in survival of 3.6% (95% CI 1.0-6.0).

Synthesis, characterization of Ag(I), Pd(II) and Pt(II) complexes of a triazine-3-thione and their interactions with bovine serum albumin

Ag(I), Pd(II) and Pt(II) complexes of 5-methoxy-5,6-diphenyl-4,5-dihydro-2H-[1,2,4]triazine-3-thione (LH(2)OCH(3)) have been synthesized and characterized by elemental analysis, molar conductance, (1)H NMR, IR spectra, UV spectra and thermal analysis (TG-DTA). The components of the three complexes are [Ag(C(15)H(10)N(3)S)](6), Pd(C(15)H(10)N(3)S)(2) and Pt(C(15)H(10)N(3)S)(2).C(3)H(6)O.2H(2)O, respectively. All the complexes are nonelectrolyte and have high thermodynamic stability. The ligand may act as bidentate NS donor for Pd(II) and Pt(II) complexes, while it seems to be bidentate NS bridging via sulphur atom for Ag(I) complex. A planar quadrangular structure is proposed for Pd(II) and Pt(II) complexes and Ag(I) complex may be a hexanuclear cluster. Their interactions with bovine serum albumin (BSA) are investigated using steady state fluorescence technology. It is observed that all of them can quench the intrinsic fluorescence of BSA through static quenching procedure. The binding constants (K(A)) at different temperatures, thermodynamic parameters enthalpy changes (DeltaH) and entropy changes (DeltaS) between BSA and the compounds are calculated. Based on the values of DeltaH and DeltaS, it is judged that the main acting force of PtL(2).C(3)H(6)O.2H(2)O with BSA may be electrostatic interaction, and for the LH(2)OCH(3), Ag(6)L(6) and PdL(2), hydrophobic and electrostatic interactions may be involved in their binding processes.

UFT (tegafur and uracil) as postoperative adjuvant chemotherapy for solid tumors (carcinoma of the lung, stomach, colon/rectum, and breast): clinical evidence, mechanism of action, and future direction

UFT (tegafur and uracil) is an oral anticancer drug that has been developed in Japan. Owing to its mild toxicity profile, UFT can be suitable in an adjuvant setting following a complete tumor resection, whereas its direct antitumor effect achieved may be insufficient for advanced unresectable disease. Therefore, a variety of adjuvant chemotherapy trials with UFT have been conducted, and results of well-designed randomized controlled trials have recently shown a survival benefit of postoperative UFT treatment in resected lung, gastric, colorectal, and breast cancer. In the present article, postoperative adjuvant trials with UFT-containing chemotherapy are reviewed, and the mechanism of action and future directions are also discussed.

Lactobacillus supplementation for diarrhoea related to chemotherapy of colorectal cancer: a randomised study

5-Fluorouracil (5-FU)-based chemotherapy is frequently associated with diarrhoea. We compared two 5-FU-based regimens and the effect of Lactobacillus and fibre supplementation on treatment tolerability. Patients diagnosed with colorectal cancer (n=150) were randomly allocated to receive monthly 5-FU and leucovorin bolus injections (the Mayo regimen) or a bimonthly 5-FU bolus plus continuous infusion (the simplified de Gramont regimen) for 24 weeks as postoperative adjuvant therapy. On the basis of random allocation, the study participants did or did not receive Lactobacillus rhamnosus GG supplementation (1-2 x 10(10) per day) and fibre (11 g guar gum per day) during chemotherapy. Patients who received Lactobacillus had less grade 3 or 4 diarrhoea (22 vs 37%, P=0.027), reported less abdominal discomfort, needed less hospital care and had fewer chemotherapy dose reductions due to bowel toxicity. No Lactobacillus-related toxicity was detected. Guar gum supplementation had no influence on chemotherapy tolerability. The simplified de Gramont regimen was associated with fewer grade 3 or 4 adverse effects than the Mayo regimen (45 vs 89%), and with less diarrhoea. We conclude that Lactobacillus GG supplementation is well tolerated and may reduce the frequency of severe diarrhoea and abdominal discomfort related to 5-FU-based chemotherapy.

Survival and disease-progression benefits with treatment regimens for advanced colorectal cancer: a meta-analysis

BACKGROUND

Many randomised trials have compared different systemic treatment regimens in patients with advanced colorectal cancer. While survival advances have apparently been achieved, the magnitude of these incremental benefits across diverse regimens is less clear. The aim of our study was to estimate the magnitude of survival and disease progression benefits with the use of different regimens in patients with advanced colorectal cancer.

METHODS

We systematically reviewed randomised trials comparing systemic treatment regimens in advanced colorectal cancer. Treatment was categorised by use of or no use of fluorouracil-based regimens, irinotecan, oxaliplatin, bevacizumab, and cetuximab. We used multiple-treatment meta-analysis methodology to combine information from direct comparisons (ie, treatments compared within a randomised trial) and indirect comparisons (ie, treatments compared between trials by combining results on how effective they are against a common comparator treatment) of different chemotherapy regimens. The primary endpoint was death and the secondary endpoint was disease progression. Monte Carlo simulations were used to establish which regimen offered the most benefit for these endpoints. We did analyses of all trials and analysed separately trials that studied first-line treatments and non-first-line treatments.

FINDINGS

242 trials published in 1967-2007 (N=56 677 patients) involved 137 different chemotherapy regimens. 37 of these trials were eligible for the multiple-treatment meta-analysis, according to our categorisation, including 47 comparisons of data on death (N=13 875 patients) and 48 comparisons of data on disease progression (N=15 158 patients). Compared with fluorouracil plus leucovorin alone, the risk of death was most decreased with the addition of irinotecan plus bevacizumab (hazard ratio [HR] 0.60, 95% credibility intervals (CrI) 0.44-0.84) and considerable benefits were also noted with addition of irinotecan plus oxaliplatin (HR 0.72 [95% CrI 0.54-0.97]); oxaliplatin plus bevacizumab (HR 0.72 [0.57-0.90]); bevacizumab alone (HR 0.78 [0.60-1.03]); and oxaliplatin alone (HR 0.87 [0.78-0.98]). The disease progression benefits were even more prominent for the addition of irinotecan plus bevacizumab (HR 0.41 [0.28-0.60]); irinotecan plus oxaliplatin (0.53 [0.38-0.73]); oxaliplatin plus bevacizumab (0.46 [0.34-0.61]); bevacizumab alone (0.56 [0.41-0.76]); oxaliplatin alone (0.64 [0.56-0.73]); irinotecan plus cetuximab (HR 0.62 [0.42-0.92]); and irinotecan alone (HR 0.73 [0.65-0.82]). Findings were similar for first-line and non-first-line treatment analyses although data were sparse for non-first-line treatment analyses. Compared with a patient with an anticipated 1-year survival who is treated with fluorouracil and leucovorin, the absolute survival benefit is estimated at 8 months' prolongation with addition of irinotecan plus bevacizumab, 4.7 months' prolongation with addition of oxaliplatin plus bevacizumab or irinotecan plus oxaliplatin, and 1-1.8 months' prolongation with addition of irinotecan alone or oxaliplatin alone.

INTERPRETATION

Distinct incremental benefits are noted for diverse chemotherapy regimens in patients with advanced colorectal cancer, with more prominent effects on disease progression than on death. More data are needed at least for the newest drugs to estimate more accurately the magnitude of the benefit derived from their use.

A prospective randomised phase III trial of adjuvant chemotherapy with 5-fluorouracil and leucovorin in patients with stage II colon cancer

The purpose of this trial was to investigate the efficacy of adjuvant chemotherapy with 5-fluorouracil (5-FU) and leucovorin (LV) in stage II colon cancer. Patients with stage II colon cancer were randomised to either adjuvant chemotherapy with 5-FU/LV (100 mg m⁻² LV+450 mg m⁻² 5-FU weekly, weeks 1–6, in 8 weeks cycles × 7) or surveillance only. Five hundred patients were evaluable for analyses. After a median follow-up of 95.6 months, 55 of 252 patients (21.8%) have died in the 5-FU/LV arm and 58 of 248 patients (23.4%) in the surveillance arm. There was no statistically significant difference in overall survival (OS) between the two treatment arms (hazard ratios, HR 0.88, 95% CI 0.61–1.27, P=0.49). The relative risk for tumour relapse was higher for patients on the surveillance arm than for those on the 5-FU/LV arm; however, this difference was not statistically significant (HR 0.69, 95% CI 0.45–1.06, P=0.09). Consequently, disease-free survival (DFS) was not significantly different between the two trial arms. In conclusion, results of this trial demonstrate a trend to a lower risk for relapse in patients treated with adjuvant 5-FU/LV for stage II colon cancer. However, in this study with limited power to detect small differences between the study arms, adjuvant chemotherapy failed to significantly improve DFS and OS.

End points for colon cancer adjuvant trials: observations and recommendations based on individual patient data from 20,898 patients enrolled onto 18 randomized trials from the ACCENT Group

PURPOSE

The traditional end point for colon adjuvant clinical trials is overall survival (OS). We previously validated disease-free survival (DFS) after 3-year follow-up as an excellent predictor of 5-year OS results. Here we explore shorter term DFS and OS end points, as well as stage dependency.

METHODS

Individual patient data from 18 phase III trials including 43 arms and 20,898 patients were pooled. Association measures included correlation of event rates within arms, correlation of hazard ratios (HRs) between arms, trial level significance comparisons (via log-rank testing), and a formal surrogacy model.

RESULTS

DFS at earlier times was less accurate in predicting OS than 3-year DFS, but 2-year DFS remained a strong predictor. DFS with 1-year minimum follow-up demonstrated perfect negative predicted value; all trials negative at 1 year for DFS were negative for 5-year OS. OS with 3-year minimum follow-up was also an excellent predictor for 5-year OS; OS at earlier time points provided inaccurate prediction. The association between 3-year DFS and 5-year OS was greater for stage III patients; correlation of HR within trials was 0.92 (95% CI, 0.85 to 0.95) for stage III patients and 0.70 (95% CI, 0.44 to 0.80) for stage II patients.

CONCLUSION

DFS outcomes after 2- or 3-year median follow-up are excellent predictors of 5-year OS. DFS outcomes are appropriate for trials in which the majority of patients are stage III. DFS after 2- or 3-year median follow-up should be considered as the primary end point in future colon adjuvant trials.

Phase III study comparing a semimonthly with a monthly regimen of fluorouracil and leucovorin as adjuvant treatment for stage II and III colon cancer patients: final results of GERCOR C96.1

PURPOSE

This randomized, 2 x 2 factorial study compared a semimonthly regimen (fluorouracil [FU] and leucovorin [LV] semi-monthly is LV5FU2) with a monthly regimen of FU and LV (mFU/LV) as well as 24 weeks versus 36 weeks of each regimen as adjuvant treatment of stage II and III colon cancer.

PATIENTS AND METHODS

LV5FU2 was administered semimonthly for 2 days as racemate (dl) or levogyre (l-; 200 or 100 mg/m(2)) as a 2-hour infusion, followed by 400 mg/m(2) FU bolus and a 600-mg/m(2) FU 22-hour continuous infusion. FU and LV were administered monthly (mFU/LV) for 5 days as dl- or l-LV 15-minute infusion, followed by a 400 mg/m(2) FU 15-minute infusion. The primary end point was disease-free survival (DFS).

RESULTS

Between September 1996 and November 1999, 905 patients with stage II (43%) and III (57%) colon cancer were enrolled. The median follow-up was 6 years. There was no statistically significant difference between mFU/LV and LV5FU2 in terms of DFS (150 v 148 events; hazard ratio [HR],1.01; 95% CI, 0.806 to 1.269; P = .94) and overall survival (OS; 104 v 103 events; HR,1.02; 95% CI, 0.77 to 1.34; P = .91). No statistical difference was observed between 24 or 36 weeks of chemotherapy. Median survival from metastatic relapse was 24 months. The survival of patients with metastatic relapse (n = 243) was significantly longer for patients with a longer time from random assignment to relapse (< 1, 1 to 2, >or= 2 years; log-rank test for trend P, .0497).

CONCLUSION

DFS and OS were not statistically different between treatment groups and treatment durations. These data confirm the value of LV5FU2 as control arm in the Multicenter International Study of Oxaliplatin/5FU-LV in the Adjuvant Treatment of Colon Cancer and Pan-European Trials in Adjuvant Colon Cancer studies.