Oral adjuvant chemotherapy with carmofur (HCFU) for colorectal cancer: five-year follow-up. Tokai HCFU Study Group--third study on colorectal cancer

Recurrence-free survival dynamics following adjuvant chemotherapy for resected colorectal cancer: A systematic review of randomized controlled trials

BACKGROUND

Several cytotoxic chemotherapies have demonstrated efficacy in improving recurrence-free survival (RFS) following resection of Stage II-IV colorectal cancer (CRC). However, the temporal dynamics of response to such adjuvant therapy have not been systematically quantified.

METHODS

The Cochrane Central Register of Trials, Medline (PubMed) and Web of Science were queried from database inception to February 23, 2023 for Phase III randomized controlled trials (RCTs) where there was a significant difference in RFS between adjuvant chemotherapy and surgery only arms. Summary data were extracted from published Kaplan-Meier curves using DigitizeIT. Absolute differences in RFS event rates were compared at matched intervals using multiple paired t-tests.

RESULTS

The initial search yielded 1469 manuscripts. After screening, 18 RCTs were eligible (14 Stage II/III; 4 Stage IV), inclusive of 16,682 patients. In the absence of adjuvant chemotherapy, the greatest rate of recurrence was observed in the first year (mean RFS event rate; 0-0.5 years: 0.22 ± 0.21; 0.5-1 years: 0.20 ± 0.09). Adjuvant chemotherapy was associated with significant decreases in the RFS event rates for the intervals 0-0.5 years (0.09 ± 0.09 vs. 0.22 ± 0.21, p < 0.001) and 0.5-1 years (0.14 ± 0.11 vs. 0.20 ± 0.09, p = 0.001) after randomization, but not at later intervals (1-5 years). In Stage IV trials, RFS event rates significantly differed for the interval 0-0.5 years (p = 0.012), corresponding with adjuvant treatment durations of 6 months. In Stage II/III trials, which included therapies of 6-24 months duration, there were marked differences in the RFS event rates between surgery and chemotherapy arms for the intervals 0-0.5 years (p < 0.001) and 0.5-1 years (p < 0.001) with smaller differences in the RFS event rates for the intervals 1-2 years (p = 0.012) and 2-3 years (p = 0.010).

CONCLUSIONS

In a systematic review of positive RCTs comparing adjuvant chemotherapy to surgery alone for Stage II-IV CRC, observed RFS improvements were driven by early divergences that occurred primarily during active cytotoxic chemotherapy. Late recurrence dynamics were not influenced by adjuvant therapy use. Such observations may have implications for the use of chemotherapy for micrometastatic clones detectable by cell-free DNA-based methodologies.

Upregulation of acid ceramidase contributes to tumor progression in tuberous sclerosis complex

Tuberous sclerosis complex (TSC) is characterized by multisystem, low-grade neoplasia involving the lung, kidneys, brain, and heart. Lymphangioleiomyomatosis (LAM) is a progressive pulmonary disease affecting almost exclusively women. TSC and LAM are both caused by mutations in TSC1 and TSC2 that result in mTORC1 hyperactivation. Here, we report that single-cell RNA sequencing of LAM lungs identified activation of genes in the sphingolipid biosynthesis pathway. Accordingly, the expression of acid ceramidase (ASAH1) and dihydroceramide desaturase (DEGS1), key enzymes controlling sphingolipid and ceramide metabolism, was significantly increased in TSC2-null cells. TSC2 negatively regulated the biosynthesis of tumorigenic sphingolipids, and suppression of ASAH1 by shRNA or the inhibitor ARN14976 (17a) resulted in markedly decreased TSC2-null cell viability. In vivo, 17a significantly decreased the growth of TSC2-null cell-derived mouse xenografts and short-term lung colonization by TSC2-null cells. Combined rapamycin and 17a treatment synergistically inhibited renal cystadenoma growth in Tsc2+/- mice, consistent with increased ASAH1 expression and activity being rapamycin insensitive. Collectively, the present study identifies rapamycin-insensitive ASAH1 upregulation in TSC2-null cells and tumors and provides evidence that targeting aberrant sphingolipid biosynthesis pathways has potential therapeutic value in mechanistic target of rapamycin complex 1-hyperactive neoplasms, including TSC and LAM.

Versatile use of Carmofur: A comprehensive review of its chemistry and pharmacology

Carmofur, 1-hexylcarbamoyl-5-fluorouracil (HCFU) is an antineoplastic drug, which has been in clinics in Japan since 1981 for the treatment of colorectal cancer. Subsequently, it was also introduced in China, Korea, and Finland. Besides colorectal cancer, it has also shown antitumor activity in other cancers such as breast, head and neck, pancreatic, gastrointestinal, and solid brain tumors. A prodrug of 5-fluorouracil (5-FU), carmofur has shown better gastrointestinal stability and superior antiproliferative activity compared to its active counterpart 5-FU. Recently, carmofur has gained attention as an acid ceramidase inhibitor and as a potential lead compound against several noncancerous diseases such as coronavirus disease 2019, Krabbe disease, acute lung injury, Parkinson's disease, dementia, childhood ependymoma etc. Carmofur has also been reported to have antifungal, and antimicrobial properties. Nevertheless, no comprehensive review is available on this drug. Herein, we summarized the chemistry, pharmacokinetics, and pharmacology of carmofur based on the literature published between January 1976 and March 2022 as identified from PubMed and Google Scholar search engines.

Adjuvant chemotherapy for rectal cancer: Current evidence and recommendations for clinical practice

While adjuvant chemotherapy is an established treatment for pathological stage II and especially stage III colon cancer, its role in the multimodal management of rectal cancer remains controversial. As a result, there is substantial variation in the use of this treatment in clinical practice. Even among centres and physicians who consider adjuvant chemotherapy as a standard treatment, notable heterogeneity exists with regard to patient selection criteria and chemotherapy regimens. The controversy around this topic is confirmed by the lack of full consensus among national and international clinical guidelines. While most of the clinical trials do not support the contention that adjuvant chemotherapy may improve survival outcomes if pre-operative (chemo)radiotherapy is also given, these suffer from many limitations that preclude drawing definitive conclusions. Nevertheless, in the era of evidence-based medicine, physicians should be guided by the available data and refrain from extrapolating results of adjuvant colon cancer trials to inform treatment decisions for rectal cancer. Patients should be informed of the evidence gap, be given the opportunity to carefully discuss pros and cons of all the possible management options and be empowered in the decision making. In this article we review the available evidence on adjuvant chemotherapy for rectal cancer and propose a risk-adapted decisional algorithm that largely relies on informed patient preferences.

Review on adjuvant chemotherapy for rectal cancer - why do treatment guidelines differ so much?

BACKGROUND

The use of postoperative adjuvant chemotherapy is controversial for rectal adenocarcinoma. Both international and national guidelines display a great span varying from recommending no adjuvant chemotherapy at all, over single drug 5-fluororuacil (5-FU), to combinations of 5-FU/oxaliplatin.

METHODS

A review of the literature was made identifying 24 randomized controlled trials on adjuvant treatment of rectal cancer based on about 10 000 patients. The trials were subdivided into a number of clinically relevant subgroups.

RESULTS

As regards patients treated with preoperative (chemo) radiotherapy, four randomized studies were found where use of adjuvant chemotherapy showed no benefit in survival. Three trials were found in which a subset of patients received preoperative (chemo) radiotherapy. Two of these trials showed a statistically significant benefit of adjuvant chemotherapy. Twenty trials were identified in which the patients did not receive preoperative (chemo) radiotherapy, including five Asian studies in which a statistically significant benefit from adjuvant chemotherapy was reported.

CONCLUSIONS

Most of the data found did not support the use of postoperative adjuvant chemotherapy for patients already treated with preoperative (chemo) radiotherapy. For patients not treated preoperatively, several studies support the use of single agent 5-FU chemotherapy. Treatment guidelines seem to differ according to if preoperative chemoradiation is considered of importance for use of adjuvant chemotherapy and if adjuvant colon cancer studies are considered transferrable to rectal cancer patients regardless of the molecular differences.

Postoperative adjuvant chemotherapy in rectal cancer operated for cure

BACKGROUND

Colorectal cancer is one of the most common types of cancer in the Western world. Apart from surgery - which remains the mainstay of treatment for resectable primary tumours - postoperative (i.e., adjuvant) chemotherapy with 5-fluorouracil (5-FU) based regimens is now the standard treatment in Dukes' C (TNM stage III) colon tumours i.e. tumours with metastases in the regional lymph nodes but no distant metastases. In contrast, the evidence for recommendations of adjuvant therapy in rectal cancer is sparse. In Europe it is generally acknowledged that locally advanced rectal tumours receive preoperative (i.e., neoadjuvant) downstaging by radiotherapy (or chemoradiotion), whereas in the US postoperative chemoradiotion is considered the treatment of choice in all Dukes' C rectal cancers. Overall, no universal consensus exists on the adjuvant treatment of surgically resectable rectal carcinoma; moreover, no formal systematic review and meta-analysis has been so far performed on this subject.

OBJECTIVES

We undertook a systematic review of the scientific literature from 1975 until March 2011 in order to quantitatively summarize the available evidence regarding the impact of postoperative adjuvant chemotherapy on the survival of patients with surgically resectable rectal cancer. The outcomes of interest were overall survival (OS) and disease-free survival (DFS).

SEARCH METHODS

CCCG standard search strategy in defined databases with the following supplementary search. 1. Rect* or colorect* - 2. Cancer or carcinom* or adenocarc* or neoplasm* or tumour - 3. Adjuv* - 4. Chemother* - 5. Postoper*

SELECTION CRITERIA

Randomised controlled trials (RCT) comparing patients undergoing surgery for rectal cancer who received no adjuvant chemotherapy with those receiving any postoperative chemotherapy regimen.

DATA COLLECTION AND ANALYSIS

Two authors extracted data and a third author performed an independent search for verification. The main outcome measure was the hazard ratio (HR) between the risk of event between the treatment arm (adjuvant chemotherapy) and the control arm (no adjuvant chemotherapy). The survival data were either entered directly in RevMan or extrapolated from Kaplan-Meier plots and then entered in RevMan. Due to expected clinical heterogeneity a random effects model was used for creating the pooled estimates of treatment efficacy.

MAIN RESULTS

A total of 21 eligible RCTs were identified and used for meta-analysis purposes. Overall, 16,215 patients with colorectal cancer were enrolled, 9,785 being affected with rectal carcinoma. Considering patients with rectal cancer only, 4,854 cases were randomized to receive potentially curative surgery of the primary tumour plus adjuvant chemotherapy and 4,367 to receive surgery plus observation. The mean number of patients enrolled was 466 (range: 54-1,243 cases). 11 RCTs had been performed in Western countries and 10 in Japan. All trials used fluoropyrimidine-based chemotherapy (no modern drugs - such as oxaliplatin, irinotecan or biological agents - were tested).Overall survival (OS) data were available in 21 RCTs and the data available for meta-analysis regarded 9,221 patients: of these, 4854 patients were randomized to adjuvant chemotherapy (treatment arm) and 4,367 patients did not receive adjuvant chemotherapy (control arm). The meta-analysis of these RCTs showed a significant reduction in the risk of death (17%) among patients undergoing postoperative chemotherapy as compared to those undergoing observation (HR=0.83, CI: 0.76-0.91). Between-study heterogeneity was moderate (I-squared=30%) but significant (P=0.09) at the 10% alpha level.Disease-free survival (DFS) data were reported in 20 RCTs, and the data suitable for meta-analysis included 8,530 patients. Of these, 4,515 patients were randomized to postoperative chemotherapy (treatment arm) and 4,015 patients received no postoperative chemotherapy (control arm). The meta-analysis of these RCTs showed a reduction in the risk of disease recurrence (25%) among patients undergoing adjuvant chemotherapy as compared to those undergoing observation (HR=0.75, CI: 0.68-0.83). Between-study heterogeneity was moderate (I-squared=41%) but significant (P=0.03).While analyzing both OS and DFS data, sensitivity analyses did not find any difference in treatment effect based on trial sample size or geographical region (Western vs Japanese). Available data were insufficient to investigate on the effect of adjuvant chemotherapy separately in different TNM stages in terms of both OS and DFS. No plausible source of heterogeneity was formally identified, although variability in treatment regimens and TNM stages of enrolled patients might have played a significant role in the difference of reported results.

AUTHORS' CONCLUSIONS

The results of this meta-analysis support the use of 5-FU based postoperative adjuvant chemotherapy for patients undergoing apparently radical surgery for non-metastatic rectal carcinoma. Available data do not allow us to define whether the efficacy of this treatment is highest in one specific TNM stage. The implementation of modern anti-cancer agents in the adjuvant setting is warranted to improve the results shown by this meta-analysis. Randomized trials of adjuvant chemotherapy for patients receiving preoperative neoadjuvant therapy are also needed in order to define the role of postoperative chemotherapy in the multimodal treatment of resectable rectal cancer.

Postoperative adjuvant chemotherapy in rectal cancer operated for cure

BACKGROUND

Colorectal cancer is one of the most common types of cancer in the Western world. Apart from surgery - which remains the mainstay of treatment for resectable primary tumours - postoperative (i.e., adjuvant) chemotherapy with 5-fluorouracil (5-FU) based regimens is now the standard treatment in Dukes' C (TNM stage III) colon tumours i.e. tumours with metastases in the regional lymph nodes but no distant metastases. In contrast, the evidence for recommendations of adjuvant therapy in rectal cancer is sparse. In Europe it is generally acknowledged that locally advanced rectal tumours receive preoperative (i.e., neoadjuvant) downstaging by radiotherapy (or chemoradiotion), whereas in the US postoperative chemoradiotion is considered the treatment of choice in all Dukes' C rectal cancers. Overall, no universal consensus exists on the adjuvant treatment of surgically resectable rectal carcinoma; moreover, no formal systematic review and meta-analysis has been so far performed on this subject.

OBJECTIVES

We undertook a systematic review of the scientific literature from 1975 until March 2011 in order to quantitatively summarize the available evidence regarding the impact of postoperative adjuvant chemotherapy on the survival of patients with surgically resectable rectal cancer. The outcomes of interest were overall survival (OS) and disease-free survival (DFS).

SEARCH METHODS

CCCG standard search strategy in defined databases with the following supplementary search. 1. Rect* or colorect* - 2. Cancer or carcinom* or adenocarc* or neoplasm* or tumour - 3. Adjuv* - 4. Chemother* - 5. Postoper*

SELECTION CRITERIA

Randomised controlled trials (RCT) comparing patients undergoing surgery for rectal cancer who received no adjuvant chemotherapy with those receiving any postoperative chemotherapy regimen.

DATA COLLECTION AND ANALYSIS

Two authors extracted data and a third author performed an independent search for verification. The main outcome measure was the hazard ratio (HR) between the risk of event between the treatment arm (adjuvant chemotherapy) and the control arm (no adjuvant chemotherapy). The survival data were either entered directly in RevMan or extrapolated from Kaplan-Meier plots and then entered in RevMan. Due to expected clinical heterogeneity a random effects model was used for creating the pooled estimates of treatment efficacy.

MAIN RESULTS

A total of 21 eligible RCTs were identified and used for meta-analysis purposes. Overall, 16,215 patients with colorectal cancer were enrolled, 9,785 being affected with rectal carcinoma. Considering patients with rectal cancer only, 4,854 cases were randomized to receive potentially curative surgery of the primary tumour plus adjuvant chemotherapy and 4,367 to receive surgery plus observation. The mean number of patients enrolled was 466 (range: 54-1,243 cases). 11 RCTs had been performed in Western countries and 10 in Japan. All trials used fluoropyrimidine-based chemotherapy (no modern drugs - such as oxaliplatin, irinotecan or biological agents - were tested).Overall survival (OS) data were available in 21 RCTs and the data available for meta-analysis regarded 9,221 patients: of these, 4854 patients were randomized to adjuvant chemotherapy (treatment arm) and 4,367 patients did not receive adjuvant chemotherapy (control arm). The meta-analysis of these RCTs showed a significant reduction in the risk of death (17%) among patients undergoing postoperative chemotherapy as compared to those undergoing observation (HR=0.83, CI: 0.76-0.91). Between-study heterogeneity was moderate (I-squared=30%) but significant (P=0.09) at the 10% alpha level.Disease-free survival (DFS) data were reported in 20 RCTs, and the data suitable for meta-analysis included 8,530 patients. Of these, 4,515 patients were randomized to postoperative chemotherapy (treatment arm) and 4,015 patients received no postoperative chemotherapy (control arm). The meta-analysis of these RCTs showed a reduction in the risk of disease recurrence (25%) among patients undergoing adjuvant chemotherapy as compared to those undergoing observation (HR=0.75, CI: 0.68-0.83). Between-study heterogeneity was moderate (I-squared=41%) but significant (P=0.03).While analyzing both OS and DFS data, sensitivity analyses did not find any difference in treatment effect based on trial sample size or geographical region (Western vs Japanese). Available data were insufficient to investigate on the effect of adjuvant chemotherapy separately in different TNM stages in terms of both OS and DFS. No plausible source of heterogeneity was formally identified, although variability in treatment regimens and TNM stages of enrolled patients might have played a significant role in the difference of reported results.

AUTHORS' CONCLUSIONS

The results of this meta-analysis support the use of 5-FU based postoperative adjuvant chemotherapy for patients undergoing apparently radical surgery for non-metastatic rectal carcinoma. Available data do not allow us to define whether the efficacy of this treatment is highest in one specific TNM stage. The implementation of modern anti-cancer agents in the adjuvant setting is warranted to improve the results shown by this meta-analysis. Randomized trials of adjuvant chemotherapy for patients receiving preoperative neoadjuvant therapy are also needed in order to define the role of postoperative chemotherapy in the multimodal treatment of resectable rectal cancer.

Adjuvant therapy for completely resected stage II colon cancer

BACKGROUND

Colon cancer is potentially curable by surgery. Although adjuvant chemotherapy benefits patients with stage III disease, there is uncertainty of such benefit in stage II colon cancer. A systematic review of the literature was performed to better define the potential benefits of adjuvant therapy for patients with stage II colon cancer.

OBJECTIVES

To determine the effects of adjuvant therapy on overall survival and disease-free survival in patients with stage II colon cancer.

SEARCH STRATEGY

Ovid MEDLINE (1986-2007), EMBASE (1980-2007), and EBM Reviews - Cochrane Central Register of Controlled Trials ( to 2007) were searched using the medical headings "colonic neoplasms", "colorectal neoplasms", "adjuvant chemotherapy", "adjuvant radiotherapy" and "immunotherapy", and the text words "colon cancer" and "colonic neoplasms". In addition, proceedings from the annual meetings of the American Society of Clinical Oncology and the European Society of Medical Oncology (1996 to 2004) as well as personal files were searched for additional information.

SELECTION CRITERIA

Randomized trials or meta-analyses containing data on stage II colon cancer patients undergoing adjuvant therapy versus surgery alone.

DATA COLLECTION AND ANALYSIS

:Three reviewers summarized the results of selected studies. The main outcomes of interest were overall and disease-free survival, however, data on toxicity and treatment delivery were also recorded.

MAIN RESULTS

With regards to the effect of adjuvant therapy on stage II colon cancer, the pooled relative risk ratio for overall survival was 0.96 (95% confidence interval 0.88, 1.05). With regards to disease-free survival, the pooled relative risk ratio was 0.83 (95% confidence interval 0.75, 0.92).

AUTHORS' CONCLUSIONS

Although there was no improvement in overall survival in the pooled analysis, we did find that disease-free survival in patients with stage II colon cancer was significantly better with the use of adjuvant therapy. It seems reasonable to discuss the benefits of adjuvant systemic chemotherapy with those stage II patients who have high risk features, including obstruction, perforation, inadequate lymph node sampling or T4 disease. The co-morbidities and likelihood of tolerating adjuvant systemic chemotherapy should be considered as well. There exists a need to further define which high-risk features in stage II colon cancer patients should be used to select patients for adjuvant therapy. Also, researchers must continue to search for other therapies which might be more effective, shorter in duration and less toxic than those available today.

Significance of histologic type of primary lesion and metastatic lymph nodes as a prognostic factor in stage III colon cancer

PURPOSE

This study was designed to investigate whether the histologic types of the primary lesion and of metastatic lymph nodes in Stage III colon cancer are useful as prognostic factors. The usefulness of adjuvant chemotherapy in a randomized, controlled trial by using these prognostic factors as stratification criteria was also investigated.

METHODS

Stage III colon cancer patients were enrolled and were divided into two groups: Group W, in which the histologic type of both primary tumors and metastatic lymph nodes was well-differentiated adenocarcinoma; and Group U, in which the primary tumors and the metastatic lymph nodes were of any type other than well-differentiated. Group W patients were assigned to Treatment Arm A (surgery alone) or Arm B (surgery, then 1-hexylcarbamoyl-5-fluorouracil); and Group U patients, to Treatment Arm C (same as B), and Arm D (surgery + 1-hexylcarbamoyl-5-fluorouracil + mitomycin C).

RESULTS

The Group W five-year survival rate was significantly superior to that in Group U (P = 0.0035). There was a better survival rate in Treatment Arm A than Arm B (P = 0.0321), but no difference between Treatment Arms C and D.

CONCLUSIONS

In Stage III colon cancer, the prognosis of cases whose primary lesion and lymph node tissues are both well differentiated is extremely good. In such cases, it is possible for adjuvant chemotherapy to have a deleterious effect, and therefore, it is not recommended.

Randomized trial of the efficacy of adjuvant chemotherapy for colon cancer with combination therapy incorporating the oral pyrimidine 1-hexylcarbamoyl-5-fluorouracil

BACKGROUND AND AIMS

The purpose of the present trial was to clarify the efficacy of postoperative adjuvant chemotherapy including an oral fluoropyrimidine anticancer drug, the 1-hexylcarbamoyl-5-fluorouracil (HCFU), for the treatment of colon cancer.

METHOD

Patients with clinical stage Dukes' B and C colon cancer, who had been treated surgically, were assigned to a chemotherapy group treated with mitomycin C, 5-fluorouracil (5-FU), and HCFU and to a control group that received no postoperative adjuvant chemotherapy.

RESULTS

Of the 1,001 patients registered for the study, 17 (1.7%) were ineligible. The incidence of toxicity was significantly higher in the chemotherapy group than in the control group. However, there were few severe side effects and no deaths related to the treatment. Overall survival showed no significant difference between the groups. The disease-free survival or the recurrence-free intervals was significantly higher in the chemotherapy group than in the control group. The incidence of hepatic recurrence was significantly (P=0.003) lower in the chemotherapy group than in the control group.

CONCLUSION

The results of this study demonstrated the efficacy of adjuvant chemotherapy for colon cancer, i.e., combined chemotherapy that included the 5-FU oral anticancer drug HCFU.

An Individual Patient Data Meta-analysis of Adjuvant Therapy with Carmofur in Patients with Curatively Resected Colon Cancer

BACKGROUND

Oral carmofur, either as a single or in combination with other chemotherapeutic agents, has been used as adjuvant chemotherapy for curatively resected colon cancer patients. Past trials and meta-analyses indicate that it is somewhat effective in extending survival of patients with this cancer. The objective of this study was to perform a reappraisal of randomized clinical trials conducted in this regard.

METHODS

We designed an individual patient-based meta-analysis of relevant clinical trials to examine the benefit of oral carmofur for curatively resected colon cancer in terms of overall survival (OS) and disease-free survival (DFS).

RESULTS

We analyzed individual patient data of three randomized clinical trials, which met the predetermined inclusion criteria. These three trials had a combined total of 2152 patients, carmofur as adjuvant chemotherapy compared with surgery-alone, 5 years follow-up, intention-to-treat-based analytic strategy and similar end points (OS and DFS). In a pooled analysis, 5 year OS rates were 80.4 and 76.4%, and 5 year DFS rates 76.9 and 71.0%, respectively, in carmofur and surgery-alone group. Oral carmofur had significant advantage over surgery-alone in terms of both OS [pooled hazard ratio, 0.82; 95% confidence interval (CI) = 0.68-0.99; P = 0.043] and DFS (pooled hazard ratio, 0.77; 95% CI = 0.65-0.91; P = 0.003).

CONCLUSIONS

This individual patient-based meta-analysis demonstrated that oral carmofur significantly improves both OS and DFS in patients with curatively resected colon cancers.

Adjuvant therapy for stage II colon cancer: a systematic review from the Cancer Care Ontario Program in evidence-based care's gastrointestinal cancer disease site group

PURPOSE

To develop a systematic review that would address the following question: Should patients with stage II colon cancer receive adjuvant therapy?

METHODS

A systematic review was undertaken to locate randomized controlled trials comparing adjuvant therapy to observation.

RESULTS

Thirty-seven trials and 11 meta-analyses were included. The evidence for stage II colon cancer comes primarily from a trial of fluorouracil plus levamisole and a meta-analysis of 1,016 patients comparing fluorouracil plus folinic acid versus observation. Neither detected an improvement in disease-free or overall survival for adjuvant therapy. A recent pooled analysis of data from seven trials observed a benefit for adjuvant therapy in a multivariate analysis for both disease-free and overall survival. The disease-free survival benefits appeared to extend to stage II patients; however, no P values were provided. A meta-analysis of chemotherapy by portal vein infusion has also shown a benefit in disease-free and overall survival for stage II patients. A meta-analysis was conducted using data on stage II patients where data were available (n = 4,187). The mortality risk ratio was 0.87 (95% CI, 0.75 to 1.01; P =.07).

CONCLUSION

There is preliminary evidence indicating that adjuvant therapy is associated with a disease-free survival benefit for patients with stage II colon cancer. These benefits are small and not necessarily associated with improved overall survival. Patients should be made aware of these results and encouraged to participate in active clinical trials. Additional investigation of newer therapies and more mature data from the presently available trials should be pursued.

Oral chemotherapy in colorectal cancer treatment: review of the literature

Recent advances in anticancer treatment have focused on the development of oral anticancer agents with the intention of improving the patients' quality of life as well as providing therapeutic alternatives to intravenous chemotherapy. Until agents such as oxaliplatin and irinotecan became available, the treatment of colorectal cancer, one the most common cancers diagnosed in industralized countries, was mainly based on 5-fluorouracil modulation. The overwhelming majority of these new drugs are pyrimidine analogues intended to replace intravenous treatment or to make the therapy more acceptable to the patients. In this article, the use of oral chemotherapy, alone or in combination with radiotherapy, in colorectal cancer is reviewed and updated. The rationale for using oral compounds is discussed and newer agents, such as oral camptothecin analogues and antiangiogenic agents, are presented with the results of their clinical and preclinical developments.

Comparative detection of lymph node micrometastases of stage II colorectal cancer by reverse transcriptase polymerase chain reaction and immunohistochemistry

PURPOSE

Inconsistent conclusions have been drawn about the clinical significance of micrometastases in lymph nodes (LNs) of node-negative colorectal cancer (CRC) patients. We performed a comparative study of detection of micrometastases using immunohistochemistry (IHC) by anti-cytokeratin antibody and carcinoembryonic antigen (CEA)-specific reverse-transcriptase polymerase chain reaction (RT-PCR) in the same patients, in an attempt to move closer to their clinical application.

PATIENTS AND METHODS

Sixty-four CRC patients, with RNA of good quality available from paraffin-embedded LN specimens, were selected from 84 stage II patients who underwent curative surgery between 1988 and 1996. We investigated associations between the presence of micrometastases by each method and prognosis.

RESULTS

Micrometastases were detected in 19 (29.6%) of 64 patients by RT-PCR and in 35 (54.7%) of 64 patients by IHC. By RT-PCR analysis, patients exhibiting a positive band for CEA mRNA had a significantly worse prognosis than those who were RT-PCR-negative, with respect to both disease-free and overall survival (P =.027 and.015, respectively). By IHC analysis, the presence of micrometastasis did not predict patient outcome in terms of either disease-free or overall survival. Infiltrating pattern of tumor growth characteristic was significantly associated with shorter disease-free survival among various clinical or pathologic factors. By multivariate Cox regression analysis, micrometastasis detected by RT-PCR and the Crohn's-like lymphoid reaction were both independent prognostic factors.

CONCLUSION

Micrometastases detected by RT-PCR, but not IHC, may be of clinical value in identifying patients who may be at high risk for recurrence of CRC and who are therefore likely to benefit from systemic adjuvant therapy.

Clinical pharmacology of anticancer agents in relation to formulations and administration routes

In the past years, alternative administration routes and pharmaceutical formulations of anticancer agents have been investigated in order to improve conventional chemotherapy treatment. The impact of these adjustments on the pharmacokinetics and pharmacodynamics is discussed. A review of the literature shows many examples of alternative administration forms of anticancer agents with improved pharmacokinetics. Local administration routes have been investigated in order to reduce the systemic toxicity and to enhance the local efficacy of conventional chemotherapy. Oral administration of anticancer agents is preferred by patients for its convenience and its potential for outpatient treatment. In addition, oral administration facilitates a prolonged exposure to the cytotoxic agent. However, poor bioavailability and substantial interpatient variability are noted as limitations for oral chemotherapy. Increased tumour selectivity can also be achieved by the use of specific pharmaceutical formulations, such as liposomes and macromolecular drug conjugates. The composition of these formulations often determine the pharmacokinetic behaviour of the formulated drug. In conclusion, several alternative administration forms of anticancer agents have been designed in the past years, with the potential for improvement of conventional chemotherapy, however, more extensive clinical evaluation of these novel strategies is warranted to prove their real clinical value.

Alcohol consumption enhances liver metastasis in colorectal carcinoma patients

BACKGROUND

It is important to identify risk factors for liver metastasis in patients with colorectal carcinoma because the liver is the most common site of recurrence. Alcohol consumption reportedly is associated with hematogenous metastasis in certain animal models. Furthermore, some studies have shown that carmofur, a derivative of 5-fluorouracil, is particularly effective as adjuvant chemotherapy for colorectal carcinoma, and may even suppress liver metastasis, although the mechanism by which this occurs remains unknown. In addition, carmofur is known to inhibit alcohol metabolism. To the authors' knowledge, the relation between liver metastasis in colorectal carcinoma and alcohol consumption has not been examined previously. Therefore, the authors studied the relations between liver metastasis in colorectal carcinoma and various clinicopathologic factors including alcohol consumption status.

METHODS

This study was comprised of 133 colorectal carcinoma patients with invasion beyond the submucosal layer who had undergone surgical resection. The subjects were examined and divided into two groups according to the occurrence or absence of liver metastasis. The relations between liver metastasis and other clinicopathologic factors were analyzed by univariate and multivariate statistical methods.

RESULTS

Univariate analysis showed alcohol consumption (P=0.0021) and blood vessel invasion (P=0.0045) were correlated with liver metastasis. Multivariate analysis showed both to be independent risk factors for liver metastasis.

CONCLUSIONS

Alcohol consumption is an independent risk factor for liver metastasis in colorectal carcinoma patients. Therefore, patients with colorectal carcinoma who drink alcohol require intensive examination and follow-up with respect to liver metastasis. Further study is necessary to confirm the effect of adjuvant chemotherapy using carmofur in colorectal carcinoma patients.