A randomized phase III multicenter trial comparing irinotecan in combination with the Nordic bolus 5-FU and folinic acid schedule or the bolus/infused de Gramont schedule (Lv5FU2) in patients with metastatic colorectal cancer

Detailed analysis of metastatic colorectal cancer patients who developed cardiotoxicity on another fluoropyrimidine and switched to S-1 treatment (subgroup analysis of the CardioSwitch-study)

BACKGROUND AND PURPOSE

The CardioSwitch-study demonstrated that patients with solid tumors who develop cardiotoxicity on capecitabine or 5-fluorouracil (5-FU) treatment can be safely switched to S-1, an alternative fluoropyrimidine (FP). In light of the European Medicines Agency approval of S-1 in metastatic colorectal cancer (mCRC), this analysis provides more detailed safety and efficacy information, and data regarding metastasectomy and/or local ablative therapy (LAT), on the mCRC patients from the original study.

MATERIALS AND METHODS

This retrospective cohort study was conducted at 12 European centers. The primary endpoint was recurrence of cardiotoxicity after switch. For this analysis, safety data are reported for 78 mCRC patients from the CardioSwitch cohort (N = 200). Detailed efficacy and outcomes data were available for 66 mCRC patients.

RESULTS

Data for the safety of S-1 in mCRC patients were similar to the original CardioSwitch cohort and that expected for FP-based treatment, with no new concerns. Recurrent cardiotoxicity (all grade 1) with S-1-based treatment occurred in 4/78 (5%) mCRC patients; all were able to complete FP treatment. Median progression-free survival from initiation of S-1-based treatment was 9.0 months and median overall survival 26.7 months. Metastasectomy and/or LAT was performed in 33/66 (50%) patients, and S-1 was successfully used in recommended neoadjuvant/conversion or adjuvant-like combination regimens and schedules as for standard FPs.

INTERPRETATION

S-1 is a safe and effective FP alternative when mCRC patients are forced to discontinue 5-FU or capecitabine due to cardiotoxicity and can be safely used in the standard recommended regimens, settings, and schedules.

A phase I/II study of arfolitixorin and 5-fluorouracil in combination with oxaliplatin (plus or minus bevacizumab) or irinotecan in metastatic colorectal cancer

Background

5-fluorouracil (5-FU) combined with a folate remains an essential treatment component for metastatic colorectal cancer (mCRC). Leucovorin is the folate most often used, but requires intracellular conversion to a reduced folate, and has high pharmacokinetic variability and limited bioavailability in patients with low folate pathway gene expression. Arfolitixorin is an immediately active form of folate, [6R]-5,10-methylenetetrahydrofolate ([6R]-MTHF), and may improve outcomes.

Patients and methods

This open-label, multicenter, phase I/II study in patients with mCRC (NCT02244632) assessed the tolerability and efficacy of first- or second-line arfolitixorin (30, 60, 120, or 240 mg/m² intravenous) with 5-FU alone, or in combination with oxaliplatin (plus or minus bevacizumab) or irinotecan, every 14 days. Safety, efficacy, and pharmacokinetics were assessed before and after four cycles (8 weeks) of treatment.

Results

In 105 treated patients, investigators reported 583 adverse events (AEs) in 86 patients (81.9%), and 256 AEs (43.9%) were potentially related to arfolitixorin and 5-FU. Dose adjustments were required in 16 patients (15.2%). At 8 weeks, 9 out of 57 patients assessed for efficacy achieved an objective response (15.8%), and all 9 achieved a partial response. Six of these nine patients had received arfolitixorin as a first-line treatment. A further 33 patients (57.9%) achieved stable disease. Pharmacokinetics were assessed in 35 patients. The average t_max was 10 min, and area under the plasma concentration–time curve from time 0 to 1 h increased linearly between 30 and 240 mg/m². No accumulation was observed for [6R]-MTHF following repeated administration, and there were no major pharmacokinetic differences between cycle 1 and cycle 4 at any dose.

Conclusions

Arfolitixorin is a well-tolerated moderator of 5-FU activity. It is suitable for further investigation in mCRC and has the potential to improve treatment outcomes in patients with low folate pathway gene expression. Arfolitixorin can easily be incorporated into current standard of care, requiring minimal changes to chemotherapy regimens.

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Arfolitixorin is an immediately active form of folate and may improve outcomes with 5-FU-based chemotherapy.

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This phase I/II clinical trial demonstrated that arfolitixorin is a well-tolerated and effective folate agent in mCRC.

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Arfolitixorin can easily be incorporated into the current standard of care and is suitable for further investigation.

A Systematic Review of Conversion to Resectability in Unresectable Metastatic Colorectal Cancer Chemotherapy Trials

OBJECTIVES

Metastasectomy in patients with metastatic colorectal cancer (mCRC) confers a significant survival benefit. We hypothesized that conversion to resectability (C2R) correlates with superior overall survival (OS) in patients with unresectable mCRC.

METHODS

A prospectively registered systematic review (PROSPERO CRD42015024104) of randomized clinical trials published after 2003 was conducted. Exposure of interest was C2R with a primary outcome of OS. Clinical trials were classified based on difference in C2R between study arms (<2%, 2% to 2.9%, ≥3%). Generalized estimating equations were used to measure associations while adjusting for multiple observations from the same trial.

RESULTS

Of 2902 studies reviewed, 30 satisfied selection criteria (n=13,618 patients). Median C2R was 7.3% (interquartile range [IQR]: 5% to 12.9%), with maximum C2R in the FOLFOX/FOLFIRI+cetuximab arm (28.6%). The median difference in C2R between 2 arms of the same study was 2.3% (IQR: 1.3% to 3.4%) with a maximum difference of 15.4% seen in FOLFOX/FOLFIRI+cetuximab versus FOLFOX/FOLFIRI. Median OS for the entire patient cohort was 20.7 months (IQR: 18.9 to 22.7 mo), with a between group difference of 1.3 months (IQR: -1.2 to 3.6 mo). The median survival difference between the 2 study arms with <2% C2R difference was 0.8 months versus 1.6 months with ≥3% C2R rates . Increasing C2R had an incremental dose-effect response on OS ( P =0.021), and higher response rates correlated with C2R rates ( P =0.003).

CONCLUSIONS

C2R occurs infrequently and variably in clinical trials enrolling patients with unresectable mCRC. Prioritization of chemotherapeutic agents that enhance C2R might improve OS of patients.

Magnitude of advantage in tumor response contributes to a better correlation between treatment effects on overall survival and progression-free survival: a literature-based meta-analysis of clinical trials in patients with metastatic colorectal cancer

BACKGROUND

Although it is suggested that the endpoints originated from the concept of tumor shrinkage dynamics, such as early tumor shrinkage and depth of response, are strongly associated with overall survival (OS) in patients with metastatic colorectal cancer (mCRC), they are yet to be validated as a single surrogate endpoint of OS by themselves. This study aimed to investigate the impact of advantage in tumor response on the correlation between treatment effects on progression-free survival (PFS) and OS in mCRC patients.

METHODS

Based on an electronic search, we identified randomized controlled trials of first-line therapy for mCRC. The impact of advantage in objective response rate (ORR) on the correlation between treatment effects on PFS and OS was evaluated based on Spearman correlation coefficients (r_s).

RESULTS

Forty-seven trials with a total of 24,018 patients were identified. The hazard ratio for PFS showed a relatively higher correlation with that for OS (r_s = 0.63) when the trials were limited to those that demonstrated a larger difference in ORR, compared to the case for trials that demonstrated a smaller difference (r_s = 0.32). This tendency was also observed in the subgroup analysis stratified by the types of treatment agents (targeted or non-targeted).

CONCLUSIONS

The magnitude of advantage in tumor response was suggested to contribute to a better prediction of OS benefit based on PFS in patients with mCRC. The accuracy of OS estimation in mCRC is expected to be improved by considering the degree of tumor shrinkage in conjunction with PFS.

Transplant oncology: assessment of response and tolerance to systemic chemotherapy for metastatic colorectal cancer after liver transplantation - a retrospective study

Solid organ recipients have a 2-5 fold increased risk of malignancy compared to the general population. Because of the broader indications for transplantation, it is anticipated that an increasing number of organ graft recipients will present with malignancy. There are limited data about responses and tolerance to chemotherapy in solid organ transplanted patients. Twenty-three of 46 colorectal cancer (CRC) patients with nonresectable liver metastases who had undergone liver transplantation (LT) in three different studies were included. All patients had received chemotherapy both prior to LT and after LT, at recurrence of metastatic CRC (mCRC). Adverse reactions (grades 3-4) and clinical and radiological outcome were retrospectively registered. Overall survival was determined from start of palliative chemotherapy after LT. No graft rejection was observed. Chemotherapy for mCRC was overall well-tolerated and there was no increased bone marrow toxicity registered after LT; however, mucositis and diarrhea were more frequent in post-LT chemotherapy. Median overall survival from start of palliative chemotherapy after LT was 13 months. No graft loss was observed when chemotherapy for mCRC was given to LT recipients who had developed nonresectable metastases. Overall, the chemotherapy for mCRC was well-tolerated, induced responses, and long-term survival was obtained in some patients.

Responsiveness to PD-1 Blockade in End-Stage Colon Cancer with Gene Locus 9p24.1 Copy-Number Gain

Most patients whose large bowel cancer has spread to other organs do not respond to immune therapy. We detected a rare gene mutation, termed 9p24.1 copy-number gain (CNG), in an otherwise incurable colorectal cancer that provoked an immune therapy response. We identified this gene mutation by gene-panel sequencing of DNA from a liver metastasis biopsy from a patient who had disease refractory to standard therapies. Following immune checkpoint blockade (ICB) with pembrolizumab (anti-PD-1), the patient experienced conversion of the tumor phenotype from one with epithelial features to that of an inflamed microenvironment, detected by high-resolution RNA sequencing. Circulating tumor DNA disappeared over the first weeks of therapy. As assessed by standard radiographic measurement, the patient had a partial response that was durable. This patient's response may support the use of histology-agnostic ICB in solid tumors that carry the rare 9p24.1 CNG.

The changing face of treatment for metastatic colorectal cancer

Introduction: Since late 1990's therapy of metastatic colorectal cancer (mCRC) patients has changed considerable, and the combination of doublet or triplet chemotherapy and a targeted agent are now routinely used. With the introduction of more intensified regimens, it has become even more important to identify patients that will benefit from and can tolerate therapy. Furthermore, the increasing understanding of the biology of mCRC has led to the discovery of new potential targets. Therefore, therapy of patients with mCRC has undergone considerable change from 'one strategy fits all' towards a more personalized therapy. Areas covered: We present an overview of the recent literature on approved systemic treatment of mCRC however with focus on how the treatment strategy has changed based on clinical and molecular parameters that presently are used routinely in the clinical situation. Expert commentary: The face of treatment of mCRC has changed from 'one strategy fits all' to a personalized approach in which both clinical, molecular parameters and the aim of therapy have to be taking into account when planning the optimal treatment strategy for the individual mCRC patient.

Reporting of patient characteristics and stratification factors in phase 3 trials investigating first-line systemic treatment of metastatic colorectal cancer: A systematic review

BACKGROUND

Patient characteristics and stratification factors are important factors influencing trial outcomes. Uniform reporting on these parameters would facilitate cross-study comparisons and extrapolation of trial results to clinical practice. In 2007, standardisation on patient characteristics reporting and stratification in metastatic colorectal cancer (mCRC) trials was proposed. We investigated the reporting of prognostic factors and implementation of this proposal in mCRC trials published from 2005 to 2016.

METHODS

We searched PubMed and Embase (January 2005 - June 2016) for first-line phase 3 mCRC trials. Patient characteristics reporting and use of stratification factors were extracted and analysed for adherence to the proposal from 2007.

RESULTS

Sixty-seven trials (35,315 patients) were identified, reporting 48 different patient characteristics (median: 9 [range: 5-18] per study). Age, gender, performance status (PS), primary tumour site and adjuvant chemotherapy were frequently reported (87%-100%), in contrast to laboratory values, such as alkaline phosphatase, lactate dehydrogenase and white blood cell count (10%-25%). We identified 29 different stratification factors (median: 3 [range: 1-9] per study). The most common strata were PS and treatment centre (>60%). A median of 8/12 (range: 4-11) of the proposed parameters was reported. Although the percentage of studies reporting each factor slightly increased over time, there was no significant correlation between publication year and adherence to the proposal from 2007.

CONCLUSIONS

We observed persistent heterogeneity in the reporting of patient characteristics and use of stratification factors in first-line mCRC trials. The proposal from 2007 has not led to increased uniformity of patient characteristics reporting and use of stratification over time. There is an urgent need to address this issue to improve the interpretation of trial results.

Population-based study on resection rates and survival in patients with colorectal liver metastasis in Norway

Background

Detailed knowledge about the proportion of patients with colorectal liver metastases (CLM) undergoing resection is sparse. The aim of this study was to analyse cumulative resection rates and survival in patients with CLM.

Methods

For this population-based study of patients developing CLM during 2011–2013, data were extracted from the Norwegian Patient Registry and the Cancer Registry of Norway.

Results

A total of 2960 patients had CLM; their median overall survival was 10·9 months. Liver resection was performed in 538 patients. The cumulative resection rate was 20·0 per cent. The cumulative resection rate was 23·3 per cent in patients aged less than 40 years, 31·1 per cent in patients aged 40–59 years, 24·7 per cent in those aged 60–74 years, 17·9 per cent in those aged 75–79 years and 4·7 per cent in patients aged 80 years or more (P &lt; 0·001). In multivariable analysis, resection rate was associated with age, extrahepatic metastases, disease-free interval and geographical region. Overall survival after diagnosis of CLM was affected by liver resection (hazard ratio (HR) 0·54, 95 per cent c.i. 0·34 to 0·86), rectal cancer (HR 0·82, 0·74 to 0·90), metachronous disease (HR 0·66, 0·60 to 0·74), increasing age (HR 1·32, 1·28 to 1·37), region, and extrahepatic metastases (HR 1·90, 1·74 to 2·07). Three- and 4-year overall survival rates after hepatectomy were 73·2 and 54·8 per cent respectively.

Conclusion

The cumulative resection rate in patients with CLM in Norway between 2011 and 2013 was 20 per cent. Resection rates varied across geographical regions, and with patient and disease characteristics.

Predictive factors for time to recurrence, treatment and post-recurrence survival in patients with initially resected colorectal liver metastases

BACKGROUND

Despite progress in resection for colorectal liver metastases (CLM), the majority of patients experience recurrence. We aimed to evaluate factors influencing time to recurrence (TTR), treatment and post-recurrence survival (PRS) related to site of recurrence.

METHODS

This is a retrospective population-based cohort study (1998-2012) of consecutive patients without extrahepatic disease treated with resection for CLM in a referral centre.

RESULTS

A total of 311 patients underwent resection for CLM. After a median follow-up of 4.2 years (range 1.2-15.2), 209 (67.4 %) patients developed recurrence, hepatic 90, extrahepatic 59 and both 60. Median TTR was 14.0 months, and 5-year recurrence-free status was 25.7 %. Five- and 10-year overall survival (OS) was 38.8 and 22.0 %, respectively. Median OS was 45 months. A multivariate analysis displayed synchronous disease (hazard ratio (HR) 1.50), American Society of Anaesthesiologists (ASA) score (HR 1.40), increasing number (HR 1.24) and size of metastases (HR 1.08) to shorten TTR (all p < 0.05). Perioperative chemotherapy (n = 59) increased overall TTR (HR 0.63) and overall survival (OS; HR 0.55). Hepatic TTR was correlated to synchronous disease (HR 2.07), number of lesions (HR 1.20), R1 resection (HR 2.00) and ASA score (HR 1.69), whereas extrahepatic TTR was correlated to N stage of the primary (HR 1.79), number (HR 1.27) and size of metastases (HR 1.16). Single-site recurrence was most common (135 of 209, 64.5 %), while 58 patients had double- and 16 triple-site relapses. Median PRS was 24.3 months. There was a difference in median PRS (months) according to site of relapse: liver 30.5, lung 32.3, abdominal 22.0, liver and lung 14.3, others 14.8 (p = 0.002). Repeated liver resections were performed in n = 57 patients resulting in 40.6 months median OS and 36.8 % 5-year OS.

CONCLUSIONS

An adverse overall TTR was correlated to number and size of metastases, ASA score and synchronous disease. Perioperative chemotherapy increased TTR and OS after surgery for CLM. Patients with solitary post-resection relapse in the liver or lungs had the potential for longevity due to multimodal treatment.

Prognostic factors for overall survival in metastatic colorectal cancer using a stop-and-go FLIRI-based treatment strategy

PURPOSE

To determine overall survival and baseline prognostic variables in a cohort of patients with metastatic colorectal cancer receiving a FLIRI-based stop-and-go treatment strategy.

METHODS

Clinical information was collected from patient files in consecutive patients treated with palliative combination chemotherapy using a stop-and-go strategy from September 2007 until June 2011. The primary outcome was overall survival. Cox regression analysis was used to examine the effect of prognostic variables on survival. Baseline variables were performance status, primary tumor site, status of primary tumor (resected or unresected), synchronous metastases, >1 metastatic site, liver-only metastases, alkaline phosphatase (>300 U/l), lactate dehydrogenase (>300 U/l), platelets (>400 × 10(9)/l), and leucocytes (>10 × 10(9)/l).

RESULTS

We included 314 patients (median age 64.5 (57-70) years). Median overall survival was 20.9 (95 % confidence interval (CI), 19.1-223.4) months with a median follow-up of 21.3 months (interquartile range (IQR) 13-34.8). Independent prognostic markers of decreased survival were PS 1 and 2 vs. 0 hazard ratio (HR) 1.47 (95 % CI 1.14-1.91, p = 0.003) and HR 2.06 (95 % CI 1.19-3.56, p = 0.01), colon as the primary tumor site HR 1.43 (95 % CI 1.09-1.88, p = 0.009), unresected primary tumor HR 2.22 (95 % CI 1.61-3.07, p < 0.001), and elevated leucocytes (>10 × 10(9)/l) HR 1.53 (95 % CI 1.12-2.09, p = 0.007).

CONCLUSIONS

Overall survival in metastatic colorectal cancer using a FLIRI-based stop-and-go strategy in an unselected consecutive cohort proved comparable to RCTs from the same period. Baseline prognostic markers of poorer prognosis were PS 1 or 2, colon as primary tumor site, unresected primary tumor, and leucocytes >10 × 10(9)/l. These variables are all easy accessible in daily clinical practice.

TIMP-1 and CEA as biomarkers in third-line treatment with irinotecan and cetuximab for metastatic colorectal cancer

KRAS wild-type (wt) status determines indication for treatment with combination therapy, including epidermal growth factor receptor (EGFR) inhibitors, but still, the overall response rate in KRAS wt patients is less than 40 %. Consequently, the majority of patients will suffer from substantial side effects and no apparent benefit. Tissue inhibitor of metalloproteinases-1 is a glycoprotein, which regulates metalloproteinases and may consequently imply a central role in tumour progression. Furthermore, it is closely related to the EGFR regulation and has shown promising potential as a biomarker in colorectal cancer (CRC). The aim of the present study was to investigate the clinical value of TIMP-1 in patients with metastatic colorectal cancer (mCRC) treated with cetuximab and irinotecan. Patients with chemotherapy-resistant mCRC referred to third-line treatment with cetuximab (initial 400 mg/m(2) followed by weekly 250 mg/m(2))/irinotecan (350 mg/m(2) q3w) were prospectively included in the biomarker study, as previously published. Pre-treatment blood samples were collected, and plasma TIMP-1 was measured by a validated in-house ELISA assay. In addition, carcinoembryonic antigen (CEA) measurement was performed with a standardised method. A total of 107 patients were included in the biomarker study. The median baseline plasma TIMP-1 level was 271.1 ng/ml (range 65.9-1432 ng/ml) with no significant associations with baseline clinical characteristics. Median baseline plasma TIMP-1 levels were significantly higher in patients with early progression compared to patients who achieved disease control, 349 ng/ml (233-398 95 % confidence interval (CI)) and 215 ng/ml (155-289 95 % CI), respectively, p = 0.03, suggesting some association with treatment efficacy. When dividing patients according to TIMP-1 tertiles, the median progression-free survival (PFS) in patients with a high level of TIMP-1 was 2.4 months (95 % CI 2.1-4.1) compared to 3.3 months (95 % CI 2.1-6.2) and 4.7 months (95 % 3.2-7.6) in patients with intermediate or low levels, respectively. Analysis of TIMP-1 as a continuous variable revealed a shorter PFS associated with increasing levels of TIMP-1 (hazard ratio (HR) 1.36). These results translated into a significantly lower overall survival (OS) in patients with a high baseline TIMP-1 level (4.5 months (95 % CI 3.4-5.4)), compared to those with intermediate or low TIMP-1 levels (7.8 months (95 % CI 4.4-13.7) and 12.0 months (95 % CI 10.1-14.3), respectively, p < 0.0001). An 83 % higher hazard for death was revealed (HR = 1.83) with each twofold increase in the TIMP-1 level. Pre-treatment levels of CEA were not associated with any of the baseline characteristics (except primary tumour localisation) or to differences in PFS or OS. The rank correlation between CEA and TIMP-1 was r = 0.50, and a test for interaction between TIMP-1 and CEA (dichotomised at 5 ng/ml) in survival analysis was not significant (p = 0.18). A multivariate analysis for PFS and OS resulted in a model with significant contributions from TIMP-1, KRAS, and the number of metastatic sites. We have confirmed the potential prognostic value of TIMP-1 measurement prior to palliative chemotherapy for mCRC. However, validation in randomised trials will be essential with the perspective of establishing a potential predictive role of plasma TIMP-1 in this setting.

Therapeutic evaluation criteria for advanced colorectal cancer: Recent progress

Evaluation criteria like overall survival (OS), progression-free survival (PFS), the response evaluation criteria in solid tumors, quality of life and adverse reactions have been widely used in clinical studies of advanced colorectal cancer. However, these criteria have different significance, and with the development of molecular targeted drugs and new therapies, the drawbacks of these criteria have been revealed. Therefore, searching for new evaluation criteria which can reflect the curative effect in the earlier stage is becoming inevitable.

Seeing the forest through the trees: a systematic review of the safety and efficacy of combination chemotherapies used in the treatment of metastatic colorectal cancer

Combinations of fluoropyrimidines with oxaliplatin or irinotecan plus a biologic agent are standard treatments for metastatic colorectal cancer (mCRC). Recent approvals of first-line cetuximab, second-line ziv-aflibercept, and regorafenib as salvage therapy have increased the complexity of the treatment armamentarium. To define optimal regimens, we systematically reviewed combination chemotherapy trials (N=83). Descriptive analyses focusing on fluoropyrimidine formulation, oxaliplatin vs irinotecan combinations, and compatibility with biologics indicated the following: infusional 5-fluorouracil (5-FU) yielded better efficacy and safety than bolus 5-FU. Capecitabine had similar outcomes and better safety than 5-FU with oxaliplatin but not irinotecan. First-line oxaliplatin and irinotecan appeared equivalent. Antiangiogenics, such as bevacizumab and ziv-aflibercept, and epidermal growth factor receptor-targeted monoclonal antibodies cetuximab and panitumumab further improved efficacy. The treatment landscape for mCRC has become complex, and we are approaching individualized therapy based on predictive factors, including KRAS mutational status. Appropriate administration of chemotherapy/biologic combinations is critical.

[What is the contribution of tumor response in colorectal cancer?]

Tumor size reduction after cancer treatment is evaluated by tumor response. It is often the primary objective of phase II clinical trials. The WHO and RECIST criteria are now internationally recognized for the quantification of tumor response in clinical trials. This literature review article focuses on the interest of measuring tumor response according to these criteria in terms of clinical benefit for patients with metastatic colorectal cancer (mCRC): metastasis resection, survival and improving quality of life. In patients with mCRC and initially resectable metastases, tumor response following preoperative chemotherapy is an independent prognosis factor for survival and a way of testing tumor sensitivity to the chemotherapy regime; it allows and/or facilitates metastases resection. In patients with mCRC and potentially resectable metastases, obtaining an objective tumor response to allow secondary metastasis resection is one of the primary objectives of chemotherapy. In patients with mCRC and non-resectable metastases, tumor response may provide individual benefit in terms of control of symptoms and quality of life and may favor a survival benefit. Despite the limitations of the RECIST criteria, no other morphological or functional radiological criterion has to date achieved consensus up in terms of availability, reproducibility, sensitivity, specificity, clinical relevance and cost. Finally, although there is no high-level of evidence, tumor response has prognostic value for metastases resection in mCRC and is a therapeutic objective in patients with potentially resectable metastases or symptomatic advanced disease.

Early tumor shrinkage in metastatic colorectal cancer: retrospective analysis from an irinotecan-based randomized first-line trial

Early tumor shrinkage (ETS) has been highlighted as a favorable prognostic factor related to progression-free survival (PFS) and overall survival (OS) in cytotoxic treatment of metastatic colorectal cancer. Data from a randomized phase III study comparing infusional 5-fluorouracil plus irinotecan (FUFIRI) versus irinotecan plus oxaliplatin (mIROX) were evaluated. Patient groups were analyzed according to the relative change in maximum tumor diameter between baseline and after 7 weeks of treatment. The ETS cohort was defined as a decrease of ≥20%. Additionally, the non-ETS cohort was subdivided into "minor shrinkage" (0-19%), "tumor progression" (any increase) and development of "new metastatic lesions". Progression-free survival and OS were estimated in all patient subgroups. Assessment of ETS was possible in 201 patients. Early tumor shrinkage was observed in 47% (94/201) and non-ETS in 53% (107/201) of patients. Patients with ETS had a more favorable outcome with regard to PFS (9.9 months vs 6.1 months, P = 0.029) and OS (27.5 months vs 17.8 months, P = 0.002). In the non-ETS subgroups, patients with "minor shrinkage" (PFS 8.4 months, OS 21.6 months) showed a markedly better outcome than patients with "early tumor progression" (PFS 4.0 months, OS 15.3 months) or with "new metastatic lesions (PFS 2.2 months, OS 7.6 months). In conclusion, ETS assessment offers accelerated response evaluation when compared to RECIST. In patients treated with chemotherapy alone, ETS ≥20% is associated with excellent outcome. Non-ETS is a heterogeneous subgroup where patients with minor shrinkage clearly benefit from treatment, and patients with early progression or development of new lesions have an unfavorable prognosis.

Non-size-based response criteria to preoperative chemotherapy in patients with colorectal liver metastases: the morphologic response criteria

Since the introduction of biologic agents, increasing data have suggested that conventional size-based RECIST criteria are not accurate in the assessment of response to therapy and non-size-based changes in tumor morphology can be a surrogate marker for assessment of chemotherapeutic effect. The morphologic response criteria are recently introduced, non-size-based criteria for patients undergoing chemotherapy for colorectal liver metastases (CLM). These novel criteria predict pathologic response and long-term survival of patients treated with preoperative chemotherapy, with or without bevacizumab, independent of their RECIST response. They have been validated in patients with resectable and unresectable CLM. These criteria are difficult to apply in small metastases and can be used as an adjunct to RECIST in the assessment of response to preoperative chemotherapy.

Pharmacogenetic markers of toxicity for chemotherapy in colorectal cancer patients

Chemotherapeutic agents used in colorectal cancer are frequently associated with severe adverse reactions that compromise the efficacy of treatment. Predicting toxicity could enable therapy to be tailored. Genetic variations have been associated with toxicity in patients treated with fluoropyrimidines (5-fluorouracil, capecitabine and tegafur), oxaliplatin, irinotecan and cetuximab. Complexity of treatment and variability in toxicity classifications make it difficult to compare studies. This article analyzes the association between toxicity and polymorphisms in DPYD, TYMS, MTHFR, ABCB1, UGT1A1, ERCC1, ERCC2, XRCC1, GSTT1 and GSTM1. In addition, the state-of-the-art and future perspectives are discussed.

Progression-free survival as a surrogate endpoint for median overall survival in metastatic colorectal cancer: literature-based analysis from 50 randomized first-line trials

PURPOSE

To evaluate progression-free survival (PFS) as a potential surrogate endpoint (SEP) for overall survival (OS) in metastatic colorectal cancer (mCRC) with a focus on applicability to trials containing targeted therapy with anti-VEGF- or anti-EGF receptor (EGFR)-directed monoclonal antibodies.

EXPERIMENTAL DESIGN

A systematic literature search of randomized trials of first-line chemotherapy for mCRC reported from January 2000 to January 2012 was conducted. Adjusted weighted linear regression was used to calculate correlations within PFS and OS (endpoints; R(EP)) and between treatment effects on PFS and on OS (treatment effects; R(TE)).

RESULTS

Fifty trials reflecting 22,736 patients met the inclusion criteria. Correlation between treatment effects on PFS and OS and between the endpoints PFS and OS was high across all studies (R(TE) = 0.87, R(EP) = 0.86). This was also observed in chemotherapy-only trials (R(TE) = 0.93, R(EP) = 0.81) but less so for trials containing monoclonal antibodies (R(TE) = 0.47; R(EP) = 0.52). Limiting the analysis to bevacizumab-based studies (11 trials, 3,310 patients) again yielded high correlations between treatment effects on PFS and on OS (R(TE) = 0.84), whereas correlation within PFS and OS was low (R(EP) = 0.45). In 7 trials (1,335 patients) investigating cetuximab- or panitumumab-based studies, contrasting correlations with very wide confidence intervals were observed (R(TE) = 0.28; R(EP) = 0.96).

CONCLUSIONS

PFS showed consistently high correlation with OS of an order that would justify its use as an SEP in chemotherapy regimens. For validation of surrogacy in anti-VEGF and anti-EGFR-directed therapies, further research and a larger set of trials is needed.

Evaluation of predictive markers for patients with advanced colorectal cancer

BACKGROUND

To evaluate the predictive and prognostic value of serum and plasma tumor markers, in comparison with clinical and biomedical parameters for response rate (RR), progression-free survival (PFS) and overall survival (OS) among patients with metastatic colorectal cancer (mCRC) treated with combination chemotherapy.

MATERIAL AND METHODS

One-hundred and six patients with mCRC from three centers, part of a multicenter study, received irinotecan with the Nordic bolus 5-fluorouracil (5-FU) and folinic acid schedule (FLIRI) or the de Gramont schedule (Lv5FU2-IRI). Blood samples for CEA, CA19-9, TPA, TIMP-1, SAA, transthyretin and CRP were taken at baseline and after two, four and eight weeks of treatment. Tumor marker levels at baseline and longitudinally were compared with responses evaluated (CT/MRI) after two and four months of treatment. The correlations to RR, PFS and OS were evaluated with regression analyses.

RESULTS

A significant correlation to OS was seen for baseline levels of all markers. In multivariate analyses with clinical parameters, TPA, CRP, SAA and TIMP-1 provided independent information. The baseline values of CEA, TPA and TIMP-1 were also significantly correlated to PFS and TPA to RR. Changes during treatment, i.e. the slope gave with the exception of CA19-9 for OS less information about outcomes. The best correlation to response was seen for CEA, CA19-9 and TPA with AUC values of 0.78, 0.83 and 0.79, respectively, using a combined model based upon an interaction between the slope and the baseline value.

CONCLUSIONS

Baseline tumor markers together with clinical parameters provide prognostic information about survival in patients with mCRC. The ability of the individual tumor markers to predict treatment response and PFS is limited. Changes in marker levels during the first two months of treatment are less informative of outcome.

Cost identification of Nordic FLIRI, Nordic FLOX, XELIRI and XELOX in first-line treatment of advanced colorectal cancer in Sweden -- a clinical practice model approach

INTRODUCTION

The role of health-related economy is crucial due to the finite healthcare resources. Intravenous (i.v.) regimes Nordic FLOX and Nordic FLIRI, and the partly oral alternatives XELIRI and XELOX are four commonly used chemotherapies in the first-line treatment of advanced colorectal cancer (CRC) in the Scandinavian countries, all with different costs.

AIM

To describe and compare costs associated with four commonly used treatments for advanced CRC in clinical routine practice. An additional aim was to evaluate the theoretical cost impact of adverse effects associated with the therapies.

MATERIAL AND METHODS

The retrospective study was carried out using observations and a clinical quality database of CRC patients treated with Nordic FLOX, Nordic FLIRI, XELIRI and XELOX as first line at an oncology clinic in Gothenburg, Sweden. The treatments are used in parallel in clinical practice. All patients treated from 2003 to 2009 were included. The clinical outcome of the therapies was equivalent; mean treatment time was 5.9-7.7 months. A clinical economic evaluation model was designed. All direct costs associated with the baseline treatment, administration of chemotherapy and drug costs were collected and evaluated.

RESULTS

The maximum cost for the four treatments was estimated to be 72 000-75 000 SEK per patient for six months, of this approximately 8000 SEK was linked to treatment of toxicity. During six months the i.v. treatments could include 17 more outpatient visits per patient compared to the oral alternatives. During treatment at the clinic around 20% of the patients were hospitalised (XELOX excluded, because of few included patients).

CONCLUSION

The results indicate that the four regimens are similar in terms of treatment costs. Different costs affect the total cost. The oral alternative makes it possible to treat additional patients with the same labour force resources. Treatment of adverse effects contributes to extensive resource use at the hospital.

Correlation of progression-free and post-progression survival with overall survival in advanced colorectal cancer

BACKGROUND

Polychemotherapy and biological drugs have increased therapeutic options and outcomes of advanced colorectal cancer (CRC). We examined the relation between progression-free survival (PFS), post-progression survival (PPS) and overall survival (OS) in trials of modern (oxaliplatin- and irinotecan-based) chemotherapy alone or with targeted therapies for advanced CRC. We also evaluated surrogacy of PFS and OS.

PATIENTS AND METHODS

A PubMed search identified 34 randomized trials. We split the OS, PFS and PPS and evaluated the correlation between OS and either PFS or PPS.

RESULTS

The median PPS and PFS were 10.75 and 8.4 months, respectively. For all trials, PPS was strongly associated with OS [regression coefficient (R2)=0.8; Spearman's rank correlation coefficient (r)=0.88], whereas PFS was moderately associated with OS (R2)=0.43; r=0.64). In trials with targeted therapies, the correlation of PPS with OS was 0.88. However, across all trials, correlation between differences in median PFS (ΔPFS) and median OS (ΔOS) is 0.59 (P=0.0007), confirming PFS/OS surrogacy.

CONCLUSION

Our findings indicate that in recent first-line, phase III, trials, OS becomes more associated with PPS than PFS. However, improvements in PFS are strongly associated with improvements in OS. In this setting so, PFS may be an appropriate surrogate for OS.

Independent radiologic review in metastatic colorectal cancer: systematic review and meta-analysis

PURPOSE

To perform a meta-analysis addressing evaluation bias in local radiologic assessment (LRA) of lesions when compared with independent radiologic review (IRR) in randomized controlled trials (RCTs) testing chemotherapy for metastatic colorectal cancer (CRC).

MATERIALS AND METHODS

MEDLINE, EMBASE, ClinicalTrials.gov, the Cochrane Library, and Web sites for major medical meetings were searched for RCTs of chemotherapy for metastatic CRC that reported response evaluation by both LRA and IRR. The risk ratios (RRs) of response in the experimental (RR(exp)) and control (RR(cont)) arms were calculated (response rate in LRA divided by response rate in IRR) for each selected study. The ratio of RR of response was calculated (RR of response of LRA divided by RR of response of IRR). The random-effects model was applied. Meta-regression was used to examine the effect of study characteristics on outcomes.

RESULTS

LRA and IRR results were concordant (13 studies; 7742 patients; ratio of RR of response = 0.97; 95% confidence interval [95% CI]: 0.90, 1.04; P = .35). However, LRA overestimated tumor response independently of therapy allocation (interaction test, P = .81) both in control (RR(cont), 1.163; 95% CI: 1.086, 1.246; P < .001) and experimental (RR(exp), 1.156; 95% CI: 1.093, 1.222; P < .001) therapies. Meta-regression did not show any effect of trial characteristics on effects.

CONCLUSION

LRA yields higher response rates in RCTs testing chemotherapy for metastatic CRC, although there was no sign of bias toward experimental therapy. The need for IRR to control evaluation bias must be reappraised.

Metastatic colorectal cancer: current treatment and future options for improved survival. Medical approach--present status

BACKGROUND

Metastatic colorectal cancer has a poor prognosis, and the majority of patients are left with palliative measures. The development seen using medical treatments are reviewed.

MATERIAL AND METHODS

A systematic approach to the literature-based evidence of effects from palliative chemotherapy and targeted drugs was aimed at.

RESULTS

The continuous improvements during the past 20-25 years have been documented in several large conclusive trials. At the end of the 1980s, the evidence that chemotherapy should be used at all was very limited, whereas presently most patients can be offered three lines of chemotherapy with or without a targeted drug based upon good scientific evidence. Median survival in trials has gradually improved from about 6 months to above 24 months in the most recent trials. Survival in the populations has, however, not improved to the same extent. Several important issues remain to be solved, such as the best sequence of treatments, what regimens to use in various situations, when to start and when to stop if a response is seen, whether cure may be possible in a small subset of patients, and socioeconomic issues. Integration of surgery and other local methods have further improved outcome for some individuals, but must be fine-tuned.

CONCLUSIONS

Progress has been rapid in advanced colorectal cancer. This is likely a result of well-designed trials in collaboration between academy and industry, showing a great interest in the disease. A multi-professional approach and future collaborations may hopefully introduce new treatment concepts, further improving outcome.

Costs and clinical outcome of neoadjuvant systemic chemotherapy followed by cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in peritoneal carcinomatosis from gastric cancer

BACKGROUND

The costs for loco-regional treatment of peritoneal carcinomatosis from gastric cancer are not well investigated. The aims of this study were to evaluate the costs and clinical outcome of systemic chemotherapy followed by cytoreductive surgery and intraperitoneal chemotherapy compared to systemic chemotherapy only in patients with peritoneal carcinomatosis from gastric cancer.

MATERIAL AND METHODS

Ten patients were scheduled for systemic chemotherapy followed by loco-regional treatment. A reference group of 10 matched control patients treated with systemic chemotherapy only were used and both groups were evaluated with respect to clinical outcome and cost.

RESULTS

The mean overall cost in the loco-regional group was $145,700 (range $49,900-$487,800) and $59,300 (range $23,000-$94,800) for the control group. The mean overall survival for the loco-regional group was 17.4 months (range 6.0-34.3), and 11.1 months (range 0.1-24.2) for the systemic chemotherapy only group. The gain in life-years was 0.52 and in quality-adjusted life-years 0.49, leading to incremental cost per life-year and quality-adjusted life-years gained of $166,716 and $175,164, for loco-regional group compared to systemic chemotherapy.

DISCUSSION

Treatment of peritoneal carcinomatosis from gastric cancer is costly irrespective of treatment modality. If the survival benefit from adding loco-regional treatment to systemic chemotherapy indicated from this comparison is true, the incremental cost is considered high.

The initial change in tumor size predicts response and survival in patients with metastatic colorectal cancer treated with combination chemotherapy

BACKGROUND

To determine whether the change in tumor diameters at the first follow-up computed tomography (CT) examination after baseline examination (first change) correlates with outcome in patients with metastatic colorectal cancer (mCRC) treated with combination chemotherapy.

PATIENTS AND METHODS

The first change was analyzed in a multicenter randomized phase III trial (Nordic VI, N = 567) comparing first-line irinotecan with either bolus or infused 5-fluorouracil. Cox proportional hazards multiple regression model and Kaplan-Meier survival analyses after correction for guarantee-time bias were carried out to evaluate correlations between first change, objective response according to RECIST 1.0, progression-free survival (PFS), and overall survival (OS).

RESULTS

The hazard ratios for PFS and OS decreased along with first change. A decrease between 10% and <30%, albeit RECIST does not regard this as a partial response, was a positive prognostic factor for PFS and OS. Patients who had new lesions or unequivocal progression of nonmeasurable lesions had a worse prognosis than those with only an increase in size of >20%.

CONCLUSIONS

The change in tumor size at the first follow-up CT is strongly prognostic for PFS and OS in mCRC.

Does socioeconomic status influence the prospect of cure from colon cancer--a population-based study in Sweden 1965-2000

AIM OF STUDY

Differences in the survival of colon cancer patients by socioeconomic status have been demonstrated in several populations, but the underlying reasons for the differences are not well understood. By simultaneously estimating the proportion of patients cured from colon cancer and the survival times of the 'uncured' we hope to increase understanding of how socioeconomic status affects survival following a diagnosis of colon cancer.

METHODS

We conducted a population-based cohort study of 58,873 patients diagnosed with colon cancer in Sweden 1965-2000. Socioeconomic status was classified based on occupation. We fitted mixture cure models and Poisson regression models adjusted for age, sex and calendar period.

RESULTS

We observed higher excess mortality, lower proportion cured and shorter survival times among the uncured in patients from lower socioeconomic groups compared to the highest socioeconomic group. There was no evidence that the gap between the socioeconomic groups reduced over time. Farmers had the lowest odds of cure (odds ratio (OR) 0.85, 95% confidence interval (CI) 0.75-0.95) compared to higher non-manual workers followed by self-employed (0.91, 0.81-1.03), manual workers (0.93, 0.85-1.03) and lower non-manual workers (0.98, 0.89-1.08).

CONCLUSION

Patients from lower socioeconomic groups in Sweden experience worse survival following a diagnosis of colon cancer. Differences exist in both the cure proportion and the survival time of the uncured, suggesting that socioeconomic differences cannot be attributed solely to lead time bias.Although this study has furthered our understanding of socioeconomic differences in survival, more detailed studies are required in order to identify, and subsequently remove, the underlying reasons for the differences.

CD133 expression in rectal cancer after preoperative chemoradiotherapy

CD133-positive cells have been reported to possess a cancer-initiating-cell phenotype and the property of resistance to chemoradiation therapy in colorectal cancer. The aim of the present study was to evaluate quantitative and locational changes in CD133-positive cells in rectal cancer patients who received preoperative chemoradiation therapy. The prognostic significance of CD133 expression in patients with preoperative chemoradiation therapy was also analyzed. Immunohistochemical staining for CD133 and cancer-initiating-cell marker CD44 were performed in 92 surgically resected rectal cancers. Of the 92 cases, 43 patients received preoperative chemoradiation therapy and 49 patients underwent surgery alone. Forty pretherapic biopsy specimens from 43 patients in preoperative chemoradiation therapy group were also analyzed. CD133-positive cases were more common in the preoperative chemoradiation therapy group than in the surgery-alone group (P = 0.03). Further, CD133-positive cases were more common in the preoperative chemoradiation therapy group than in pretherapic biopsy specimens (P = 0.02). In the preoperative chemoradiation therapy group, the CD133-positive cases showed poorer prognosis than the CD133-negative cases. On the other hand, the frequency of CD44-positive case within cancer tissue was similar between the preoperative chemoradiation therapy group and the surgery-alone group. CD44 expression in the preoperative chemoradiation therapy group was not associated with prognosis. CD44- and CD133-positive cells were distributed evenly within the tumor both in the preoperative chemoradiation therapy group and surgery-alone group, and locational alteration was not observed. The therapy-resistant ability of CD133-positive cells can be associated with poor outcome in the patients with preoperative chemoradiation therapy.

Prediction of irinotecan and 5-fluorouracil toxicity and response in patients with advanced colorectal cancer

Irinotecan and 5-fluorouracil (5-FU) are used to treat metastatic colorectal cancer. Irinotecan's active metabolite is inactivated by UDP-glucuronosyltransferase 1A1 (UGT1A1), which is deficient in Gilbert's syndrome. Irinotecan and metabolites are transported by P-glycoprotein, encoded by ABCB1. 5-FU targets folate metabolism through inhibition of thymidylate synthase (TYMS). Methylenetetrahydrofolate reductase (MTHFR) generates active folate necessary for haematopoiesis. We retrospectively genotyped 140 Swedish and Norwegian irinotecan and 5-FU-treated colorectal cancer patients from the Nordic VI clinical trial for selected variants of UGT1A1, ABCB1, TYMS and MTHFR. We found an increased risk of clinically relevant early toxicity in patients carrying the ABCB1 3435 T/T genotype, Odds ratio (OR)=3.79 (95% confidence interval (CI)=1.09–13.2), and in patients carrying the UGT1A1^*28/^*28 genotype, OR=4.43 (95% CI=1.30–15.2). Patients with UGT1A1^*28/^*28 had an especially high risk of neutropenia, OR=6.87 (95% CI=1.70–27.7). Patients who had reacted with toxicity during the first two cycles were in total treated with fewer cycles (P<0.001), and less often responded to treatment (P<0.001). Genetic variation in ABCB1 was associated with both early toxicity and lower response to treatment. Carriers of the ABCB1 1236T-2677T-3435T haplotype responded to treatment less frequently (43 vs 67%, P=0.027), and survived shorter time, OR=1.56 (95% CI=1.01–2.45).

Low-dose continuous 5-fluorouracil infusion stimulates VEGF-A-mediated angiogenesis

BACKGROUND

Tumor growth is angiogenesis-dependent. Animal studies have demonstrated that frequent administration of chemotherapeutics may have marked antiangiogenic effects and improved antitumor effects, with less severe toxic side-effects than intermittent maximum tolerated dose chemotherapy. Currently, research focused on low-dose antiangiogenic chemotherapy is increasing. We have recently reported that certain chemotherapeutics, including 5-fluorouracil (5-FU), may in fact stimulate angiogenesis in the tumor-free rat mesenteric window assay. The aim of the present study was to extend the investigation of the angiogenesis-modulating effects of 5-FU by prolonging the continuous infusion treatment time.

METHOD

Angiogenesis was induced in the mesenteric test tissue in adult male Sprague-Dawley rats by i.p. injection of VEGF-A, which is a key angiogenic factor in most tumors. During the subsequent angiogenesis, 5-FU was delivered continuously for 14 days by an osmotic pump implanted subcutaneously. The angiogenic response was analyzed by morphometry in the mesenteric windows.

RESULTS

The 14-days continuous infusion of 5-FU significantly stimulated angiogenesis. Thus the possibility that the previously reported surprising proangiogenic effect of 5-FU reflected an insufficiently long treatment period can be ruled out.

CONCLUSION

The finding that continuously infused 5-FU is able to stimulate angiogenesis in the present rat model of angiogenesis warrants investigation of the mechanisms behind this unexpected finding. It may further have implications for the choice of antiangiogenic chemotherapeutic schedule used for cancer patients.

An explorative randomised phase II study of sequential chemotherapy in advanced upper gastrointestinal cancer

The feasibility, safety, and efficacy of planned sequential administration of docetaxel and irinotecan with 5-fluorouracil (5-FU)/leucovorin in advanced upper gastrointestinal adenocarcinoma (UGIA) are unknown. Seventy-three patients with gastric (GC; n = 22), pancreatic (PC; n = 28) or biliary cancer (BC; n = 23) were randomised to start with 45 mg/m(2) docetaxel or 180 mg/m(2) irinotecan combined with 5-FU/leucovorin every 2nd week. After every 2nd course, the patients were crossed over to the other combination. Treatment was given for a maximum of 12 courses. Quality-of-life (QoL) was evaluated during the first two months using the EORTC QLQ-C30. Eighteen patients (25%; GC 32%, PC 21%, BC 22%) demonstrated partial response (PR) and 21 (29%) had prolonged stable disease. Mean QoL scores were low at baseline. Twenty-three (32%) patients had improved QoL using a summary measure and 13 were stable. Median time to progression was 4.4 months and overall survival 8.2 months. The treatments were reasonably well tolerated. Grade 3-4 toxicities were slightly more common for the docetaxel combination. There were two treatment-related deaths. Planned sequential treatment with docetaxel or irinotecan with 5-FU/leucovorin is feasible, reasonably tolerable and appears active in advanced UGIA.

Early prediction of response to first-line chemotherapy by sequential [18F]-2-fluoro-2-deoxy-D-glucose positron emission tomography in patients with advanced colorectal cancer

BACKGROUND

To evaluate [(18)F]-2-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET), for early evaluation of response to palliative chemotherapy and for prediction of long-term outcome, in patients with metastatic colorectal cancer (mCRC).

PATIENTS AND METHODS

In a randomized trial, patients with mCRC received irinotecan-based combination chemotherapy. FDG-PET was carried out before treatment and after two cycles in 51 patients at two centers. Visual changes in tumor FDG uptake and changes measured semi-automatically, as standard uptake values (SUVs), were compared with radiological response after four and eight cycles.

RESULTS

The mean baseline SUV for all tumor lesions per patient was higher in nonresponders than in responders (mean 7.4 versus 5.6, P = 0.02). There was a strong correlation between metabolic response (changes in SUV) and objective response (r = 0.57, P = 0.00001), with a sensitivity of 77% and a specificity of 76%. There was no significant correlation between metabolic response and time to progression (P = 0.5) or overall survival (P = 0.1).

CONCLUSIONS

Although metabolic response assessed by FDG-PET reflects radiological tumor volume changes, the sensitivity and specificity are too low to support the routine use of PET in mCRC. Furthermore, PET failed to reflect long-term outcome and can, thus, not be used as surrogate end point for hard endpoint benefit.

Serum vitamin B12 and folate status among patients with chemotherapy treatment for advanced colorectal cancer

BACKGROUND

There are conflicting results on the role of cobalamin and folate for epidemiology and carcinogenesis in colorectal cancer patients and the need of supplementation for prevention of chemotherapy toxicity.

PATIENTS AND METHODS

Serum cobalamin, folate, and homocysteine were analysed before and during the treatment of 93 patients with advanced colorectal cancer (ACRC) with first-line chemotherapy treatment. This cohort was compared with a healthy control group of 224 individuals.

RESULTS

Patients with ACRC had similar cobalamin, folate, and homocysteine values as the healthy control group. There were no correlations between serum cobalamin, folate, and homocysteine values and objective response. There were no correlations to anaemia or other severe toxicity for cobalamin and homocysteine. A total of 12 patients had folate deficiency, and 10 of those suffered from severe toxicity (grade 3 or more). All patients had markedly increased folate values after 2 months of treatment. Folate and homocysteine did not predict patient outcome; however, patients with subclinically low cobalamin values (<300 pmol/L) had significant better overall survival and time to progression than patients with normal or high cobalamin values.

CONCLUSION

Patients with ACRC seem to have fairly adequate cobalamin and folate status before and during chemotherapy treatment. This study indicates that ACRC patients receiving chemotherapy do not need supplementation with vitamin B12 and folate. A minor portion of the patients had folate deficiency, and most of those patients had severe toxicity. Patients with subclinically low cobalamin values had surprisingly better survival.