A new blood-based screening test for colorectal cancer: a pilot study

Background: Colorectal cancer (CRC) can be cured when diagnosed in its early or precancerous (adenoma) stages. Mostly due to poor compliance towards invasive screening procedures, detection rates for adenoma and early CRCs are still low. Available non-invasive screening tests have unfortunately low sensitivity and specificity performances. Therefore, there is a large unmet need calling for a cost-effective, reliable and non-invasive test to screen for early neoplastic and pre-neoplastic lesions. Objective: To develop a routine screening test based on a nucleic acids multi-gene assay performed on peripheral blood mononuclear cells (PBMCs) that can detect early CRCs and adenomas. Methods: 116 patients (mean age: 55 years; range: 18 to 74 years; female/male ration 0.98) were included in this pilot, nonblinded, colonoscopy-controlled study. Colonoscopy revealed 21 patients with CRC, 30 patients with adenoma bigger than 1 cm, 24 patients with inflammatory bowel disease (IBD) and 41 patients had no neoplastic or inflammatory lesions. Blood samples were taken from each patient the day of the colonoscopy and PBMCs were purified. Total RNA was extracted following standard procedures. Multiplex RT-qPCR was applied on 92 different candidate biomarkers. Different univariate and multivariate statistical methods were applied on these candidates, and among them, 57 biomarkers with significant p values (<0.01, Wilcoxon test) were selected, including ADAMTS1, MMP9, CXCL10, CXCR4, VEGFA and CDH1. Two distinct biomarker signatures are used to separate patients without neoplastic lesion from those with cancer (named COLOX 1 test), respectively from those with adenoma (named COLOX 2 test). Result: COLOX 1 and 2 tests have successfully separated patients without neoplastic lesion from those with CRC (sensitivity 70%, specificity 90%, AUC 0.88), respectively from those with adenoma bigger than 1cm (sensitivity 61%, specificity 80%, AUC 0.80). 6/24 patients in the IBD group have a positive COLOX 1 test. Conclusion: These two COLOX tests demonstrated an acceptable sensitivity and a high specificity to detect the presence of CRCs and adenomas bigger than 1 cm. The false positives COLOX 1 test in IBD patients could possibly be due to the chronic inflammatory state. A prospective, multicenter, pivotal study is underway in order to confirm these promising results in a larger cohort.

Dépistage du cancer colorectal: surveillance après résection de polypes coliques ou d'un cancer colorectal [Colorectal cancer screening: follow-up of patients with adenomatous and colorectal cancer]

Les différentes méthodes de dépistage du cancer colorectal sont présentées et commentées. Nos recommandations restent inchangées : à partir de 50 ans, une coloscopie de dépistage est indiquée chez les personnes saines sans risque particulier de développer un cancer colorectal. Les acquisitions de 2007 : lors d'une conférence de consensus interdisciplinaire, de nouvelles recommandations suisses ont été élaborées pour le suivi de patients opérés d'un cancer colorectal ou après polypectomie colorectale. The different methods of colorectal cancer screening are discussed. Our recommendations had not changed: we recommend as colorectal cancer screening a colonoscopy at the age of 50 years in all healthy persons with average risk for colorectal cancer. A 2007 interdisciplinary consensus conference revised the Swiss recommendations for the follow-up of patients with operated colorectal cancer or after polypectomy

The "reversed" treatment approach for synchronous liver metastases and colorectal cancer. Feasability and first results

Background: The « reversed treatment» approach inverts the treatment sequence of¦advanced synchronous colorectal liver metastases - i.e. the liver metastasis is¦treated first, followed by resection of the primary tumor. Chemotherapy is performed¦before and after liver surgery. We recently started to use a reversed treatment¦approach in selected patients. The aim of this study is to critically assess this new¦treatment modality.¦Methods: Nine patients (7 male, 2 female, mean age 62 years) benefited from this¦new treatment between November 2008 and May 2010. The data were collected¦retrospectively.¦Results: All patients responded to the neoadjuvant chemotherapy. The median¦number of liver metastases was 6 (range 1 - 22). The median size of the largest liver¦metastases was 4.3 cm (range 2.6 - 13 cm). Three patients had portal vein¦embolization prior to liver surgery. Two patients could not complete the treatment.¦One had to undergo emergency surgery for occluding colonic tumor. The second one¦showed liver recurrence before starting the adjuvant chemotherapy. The seven¦patients who completed the treatment are still alive after a median time of 27 months¦(range 17 - 37 months). Seven of them had recurrence (1 rectal, 6 liver). The median¦disease-free survival was 9 months (range 0 - 17 months).¦Conclusion: Based on our preliminary experiences, the reversed strategy shows¦encouraging results for the treatment of advanced synchronous colorectal liver¦metastases in well selected patients. The treatment was generally well tolerated and¦long term survival seems to be prolonged.

Risk factors for survival after lung metastasectomy in colorectal cancer patients: a systematic review and meta-analysis.

BACKGROUND: Resection of lung metastases (LM) from colorectal cancer (CRC) is increasingly performed with a curative intent. It is currently not possible to identify those CRC patients who may benefit the most from this surgical strategy. The aim of this study was to perform a systematic review of risk factors for survival after lung metastasectomy for CRC. METHODS: We performed a meta-analysis of series published between 2000 and 2011, which focused on surgical management of LM from CRC and included more than 40 patients each. Pooled hazard ratios (HR) were calculated by using random effects model for parameters considered as potential prognostic factors. RESULTS: Twenty-five studies including a total of 2925 patients were considered in this analysis. Four parameters were associated with poor survival: (1) a short disease-free interval between primary tumor resection and development of LM (HR 1.59, 95 % confidence interval [CI] 1.27-1.98); (2) multiple LM (HR 2.04, 95 % CI 1.72-2.41); (3) positive hilar and/or mediastinal lymph nodes (HR 1.65, 95 % CI 1.35-2.02); and (4) elevated prethoracotomy carcinoembryonic antigen (HR 1.91, 95 % CI 1.57-2.32). By comparison, a history of resected liver metastases (HR 1.22, 95 % CI 0.91-1.64) did not achieve statistical significance. CONCLUSIONS: Clinical variables associated with prolonged survival after surgery for LM in CRC patients include prolonged disease-free interval between primary tumor and metastatic spread, normal prethoracotomy carcinoembryonic antigen, absence of thoracic node involvement, and a single pulmonary lesion.

Nodal staging in colorectal cancer: should distant lymph nodes be recovered in surgical specimens?

To assess the value of sampling lymph nodes located far sidelong colorectal cancer specimens, we analyzed retrospectively surgical specimens from 345 colorectal cancer patients. The mesocolic and perirectal fat was divided into 2 fractions: close to (<5 cm) and distant from (>5 cm) the tumor. Tumors were located in the cecum (n = 61), ascending colon (n = 29), transverse colon (n = 31), descending colon (n = 27), sigmoid colon (n = 108), and rectum (n = 89). The median number of lymph nodes sampled was 17 in both fractions (range, 4-66), 12 (range, 0-46) in the close fraction, and 3 (range, 0-33) in the distant fraction. There were 169 pN0, 104 pN1, and 72 pN2 cases. The pN staging was accurate in all cases except 10 based on the close fraction alone; of these, 6 were upstaged from pN0 to pN1 and 4 from pN1 to pN2 when the distant fraction was considered. Among pN1-upstaged cases, 5 were rectal (3/5 with neoadjuvant radiotherapy) and 1 colonic. In the colon, we found that lymph node location is more important than lymph node number because metastatic lymph nodes were present mostly in the peritumoral area. This suggests that lymph nodes should be initially recovered from the pericolic fat close to the tumor. If there are less than 4 positive lymph nodes and less than 12 lymph nodes examined in total, additional lymph nodes should be retrieved from the distal fraction for potential upstaging. In the rectum, systematic sampling of close and distant lymph nodes is mandatory because in rare cases, metastases are detected only in distant lymph nodes, particularly in patients who have undergone neoadjuvant radiotherapy.

An EORTC phase I itudy of bortezomib in combination with oxaliplatin, leucovorin and 5-fluorouracil in patients with advanced colorectal cancer.

The combination of oxaliplatin, leucovorin and 5-fluorouracil (FOLFOX-4) is still a reference regimen in advanced colorectal cancer; however, the addition of new biologic compounds represents a significant way forward. Bortezomib is an inhibitor of proteasome, a multicatalytic enzyme complex that degrades several intracellular proteins. In this study, escalating doses of Bortezomib were administered along with the standard FOLFOX-4 doses, in order to evaluate the dose-limiting toxicity (DLT), toxicity profile and activity of the combination. Patients with advanced colorectal cancer, unpretreated for metastatic disease, were enroled in the study. Bortezomib starting dose was 1.3mg/m(2), which was to be escalated in the subsequent steps according to the toxicities observed after first cycle. Exploratory pharmacogenetics research was conducted by analysing the association between clinical outcomes and polymorphisms in candidate genes for response to each of the used drugs. Correlation between tumour marker changes and response was also investigated. One mg/m(2) (DL-1) was defined as being the maximum tolerated dose since only 1 DLT was observed in 6 patients. The main toxicities were haematologic, neuropathy, diarrhoea and fatigue. Amongst 13 evaluable patients, five had a partial response, five had a stable disease and three patients progressed. Two patients are long-term survivors after a combined chemosurgical approach. Further trials of the current combination may be justified.

p53 and Ki-ras as prognostic factors for Dukes' stage B colorectal cancer.

Mutations of the TP53 and Ki-ras genes have been reported to be of prognostic importance in colorectal carcinomas. An increased intracellular concentration of the p53 protein, although not identical to, is sometimes seen in tumours with TP53 mutation and has been correlated with poor prognosis in some tumour types. Previous colorectal cancer studies, addressing the prognostic importance of Ki-ras mutation and TP53 aberrations, yielded contradictory results. The aim of this study was to determine in a clinically and therapeutically homogeneous group of 122 sporadic Dukes' B colorectal carcinomas with a median follow-up of 67 months (3-144 months) whether or not p53 protein expression, TP53 mutation and K-ras mutation correlated with prognosis. p53 staining was performed by immunohistochemistry, using the monoclonal antibody DO7 on paraffin-embedded tissue. Mutations in exons 5-8 of the TP53 gene and in codons 12 and 13 of the K-ras gene were assayed in paraffin-embedded tissue by the single-strand conformation polymorphism (SSCP) assay. Nuclear p53 staining was found in 57 (47%) tumours. Aberrant migration patterns indicating mutation of the TP53 gene were found in 39 (32%) tumours. Forty-six carcinomas (38%) showed a mutation of the Ki-ras codons 12 or 13. In a univariate analysis, patients with wild-type TP53 status showed a trend towards better survival, compared with those with mutated TP53 (log-rank test, P = 0.051). Likewise, tumours immunohistochemically positive for p53 showed a worse prognosis than p53-negative tumours (P = 0.010). The presence or absence of mutations in Ki-ras did not correlate with prognosis (P = 0.703). In multivariate analysis, only p53 immunoreactivity emerged as an independent marker for prognosis hazard ratio (HR) = 2.16, 95% confidence interval (CI) 1.12-4.11, P = 0.02). Assessment of p53 protein expression is more discriminative than TP53 mutation to predict the outcome of Dukes' stage B tumours and could be a useful tool to identify patients who might benefit from adjuvant therapy.

Metabolic syndrome is associated with colorectal cancer in men.

AIM OF THE STUDY: We assessed the relation between metabolic syndrome (MetS) and its components and colorectal cancer. METHODS: We analysed data from a multicentre case-control study conducted in Italy and Switzerland, including 1378 cases of colon cancer, 878 cases of rectal cancer and 4661 controls. All cases were incident and histologically confirmed. Controls were subjects admitted to the same hospitals as cases with acute non-malignant conditions. MetS was defined according to the International Diabetes Federation criteria. Odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) were estimated by multiple logistic regression models, including terms for major identified confounding factors for colorectal cancer. RESULTS: With reference to each component of the MetS, the ORs of colorectal cancer in men were 1.27 (95% CI, 0.95-1.69) for diabetes, 1.24 (95% CI, 1.03-1.48) for hypertension, 1.14 (95% CI, 0.93-1.40) for hypercholesterolaemia and 1.26 (95% CI, 1.08-1.48) for overweight at age 30. The corresponding ORs in women were 1.20 (95% CI, 0.82-1.75), 0.87 (95% CI, 0.71-1.06), 0.83 (95% CI, 0.66-1.03) and 1.06 (95% CI, 0.86-1.30). Colorectal cancer risk was increased in men (OR=1.86; 95% CI, 1.21-2.86), but not in women (OR=1.13; 95% CI, 0.66-1.93), with MetS. The ORs were 2.09 (95% CI, 1.38-3.18) in men and 1.15 (95% CI, 0.68-1.94) in women with > or =3 components of the MetS, as compared to no component. Results were similar for colon and rectal cancers. CONCLUSION: This study supports a direct association between MetS and both colon and rectal cancers in men, but not in women.

A colorectal cancer classification system that associates cellular phenotype and responses to therapy.

Colorectal cancer (CRC) is a major cause of cancer mortality. Whereas some patients respond well to therapy, others do not, and thus more precise, individualized treatment strategies are needed. To that end, we analyzed gene expression profiles from 1,290 CRC tumors using consensus-based unsupervised clustering. The resultant clusters were then associated with therapeutic response data to the epidermal growth factor receptor-targeted drug cetuximab in 80 patients. The results of these studies define six clinically relevant CRC subtypes. Each subtype shares similarities to distinct cell types within the normal colon crypt and shows differing degrees of 'stemness' and Wnt signaling. Subtype-specific gene signatures are proposed to identify these subtypes. Three subtypes have markedly better disease-free survival (DFS) after surgical resection, suggesting these patients might be spared from the adverse effects of chemotherapy when they have localized disease. One of these three subtypes, identified by filamin A expression, does not respond to cetuximab but may respond to cMET receptor tyrosine kinase inhibitors in the metastatic setting. Two other subtypes, with poor and intermediate DFS, associate with improved response to the chemotherapy regimen FOLFIRI in adjuvant or metastatic settings. Development of clinically deployable assays for these subtypes and of subtype-specific therapies may contribute to more effective management of this challenging disease.

Identification by Real-time PCR of 13 mature microRNAs differentially expressed in colorectal cancer and non-tumoral tissues

MicroRNAs (miRNAs) are short non-coding RNA molecules playing regulatory roles by repressing translation or cleaving RNA transcripts. Although the number of verified human miRNA is still expanding, only few have been functionally described. However, emerging evidences suggest the potential involvement of altered regulation of miRNA in pathogenesis of cancers and these genes are thought to function as both tumours suppressor and oncogenes. In our study, we examined by Real-Time PCR the expression of 156 mature miRNA in colorectal cancer. The analysis by several bioinformatics algorithms of colorectal tumours and adjacent non-neoplastic tissues from patients and colorectal cancer cell lines allowed identifying a group of 13 miRNA whose expression is significantly altered in this tumor. The most significantly deregulated miRNA being miR-31, miR-96, miR-133b, miR-135b, miR-145, and miR-183. In addition, the expression level of miR-31 was correlated with the stage of CRC tumor. Our results suggest that miRNA expression profile could have relevance to the biological and clinical behavior of colorectal neoplasia.

COLOX: a new blood-based test for colorectal cancer (CRC)screening

BACKGROUND: The objective is to develop a cost-effective, reliable and non invasive screening test able to detect early CRCs and adenomas. This is done on a nucleic acids multigene assay performed on peripheral blood mononuclear cells (PBMCs). METHODS: A colonoscopy-controlled study was conducted on 179 subjects. 92 subjects (21 CRC, 30 adenoma >1 cm and 41 controls) were used as training set to generate a signature. Other 48 subjects kept blinded (controls, CRC and polyps) were used as a test set. To determine organ and disease specificity 38 subjects were used: 24 with inflammatory bowel disease (IBD),14 with other cancers (OC). Blood samples were taken and PBMCs were purified. After the RNA extraction, multiplex RT-qPCR was applied on 92 different candidate biomarkers. After different univariate and multivariate analysis 60 biomarkers with significant p-values (<0.01) were selected. 2 distinct biomarker signatures are used to separate patients without lesion from those with CRC or with adenoma, named COLOX CRC and COLOX POL. COLOX performances were validated using random resampling method, bootstrap. RESULTS: COLOX CRC and POL tests successfully separate patients without lesions from those with CRC (Se 67%, Sp 93%, AUC 0.87), and from those with adenoma > 1cm (Se 63%, Sp 83%, AUC 0.77). 6/24 patients in the IBD group and 1/14 patients in the OC group have a positive COLOX CRC. CONCLUSION: The two COLOX tests demonstrated a high Se and Sp to detect the presence of CRCs and adenomas > 1 cm. A prospective, multicenter, pivotal study is underway in order to confirm these promising results in a larger cohort.

Combined radioimmunotherapy and radiotherapy of liver metastases from colorectal cancer: a feasibility study.

BACKGROUND: A combination of radioimmunotherapy (RIT) and radiotherapy (RT) should allow one to increase the dose of radiation targeting a particular tumour without the concomitant increase of toxic side effects. This might be obtained if the dose limiting side effect of each individual radiation therapy concerned different organs. METHODS: Six patients with limited liver metastatic disease from colorectal cancer were treated with 6.9 GBq (range 4.7 to 8.4 GBq) 131I-labelled anti-CEA MAb F(ab')2 fragments combined with 20 Gy RT to the liver. Both treatments were given in close association, according to timing schedules evaluated in animals that gave the best results. RESULTS: Reversible bone marrow and liver toxicity was observed in 6 and 5 patients, respectively. Three patients who first received 20 Gy RT to the liver, showed a significant platelet drop upon completion of RT. Repeat computerized tomography (CT) after 2 months showed a minor response in 1 patient and stable disease in 3 patients. CONCLUSION: The study shows potential ways of combining RIT and RT, suggesting that this combination is feasible for the treatment of liver metastases.

Risk factors for young-onset colorectal cancer.

PURPOSE: We investigated risk factors for colorectal cancer in early-onset cancers, to provide quantitative estimates for major selected risk factors. METHODS: We analyzed data from three Italian and Swiss case-control studies conducted between 1985 and 2009, including 329 colorectal cancer cases and 1,361 controls aged ≤45 years. We computed odds ratios (ORs) from unconditional logistic regression models, adjusted for major confounding factors. RESULTS: The OR of young-onset colorectal cancer was 4.50 for family history of colorectal cancer in first-degree relatives, the association being higher in subjects with affected siblings (OR 11.68) than parents (OR 3.75). The ORs of young-onset colorectal cancer were 1.56 for ≥14 drinks/week of alcohol, 1.56 for the highest tertile of processed meat, 0.40 for vegetables, 0.75 for fruit, and 0.78 for fish intake. Among micronutrients, the ORs were 0.52 for β-carotene, 0.68 for vitamin C, 0.38 for vitamin E, and 0.59 for folate. No significant associations emerged for physical activity, overweight, and diabetes. CONCLUSIONS: This study-the largest on young-onset colorectal cancer-confirms that several recognized risk factors for colorectal cancer are also relevant determinants of young-onset colorectal cancer. Family history of colorectal cancer in particular is a stronger risk factor in young subjects, as compared to middle age and elderly ones.

Colorectal cancer detection: how well do appropriateness criteria perform?

Comment on: Hassan C, Di Giulio E, Pickhardt PJ, Zullo A, Laghi A, Kim DH, Iafrate F, Morini S. Cost effectiveness of colonoscopy, based on the appropriateness of an indication. Clin Gastroenterol Hepatol. 2008 Nov;6(11):1231-6.

Two Signatures For A New Blood-Based Test For Colorectal Cancer Screening

Background: Detection rates for adenoma and early colorectal cancer (CRC) are unsatisfactory due to low compliance towards invasive screening procedures such as colonoscopy. There is a large unmet screening need calling for an accurate, non-invasive and cost-effective test to screen for early neoplastic and pre-neoplastic lesions. Our goal is to identify effective biomarker combinations to develop a screening test aimed at detecting precancerous lesions and early CRC stages, based on a multigene assay performed on peripheral blood mononuclear cells (PBMC).Methods: A pilot study was conducted on 92 subjects. Colonoscopy revealed 21 CRC, 30 adenomas larger than 1 cm and 41 healthy controls. A panel of 103 biomarkers was selected by two approaches: a candidate gene approach based on literature review and whole transcriptome analysis of a subset of this cohort by Illumina TAG profiling. Blood samples were taken from each patient and PBMC purified. Total RNA was extracted and the 103 biomarkers were tested by multiplex RT-qPCR on the cohort. Different univariate and multivariate statistical methods were applied on the PCR data and 60 biomarkers, with significant p-value (< 0.01) for most of the methods, were selected.Results: The 60 biomarkers are involved in several different biological functions, such as cell adhesion, cell motility, cell signaling, cell proliferation, development and cancer. Two distinct molecular signatures derived from the biomarker combinations were established based on penalized logistic regression to separate patients without lesion from those with CRC or adenoma. These signatures were validated using bootstrapping method, leading to a separation of patients without lesion from those with CRC (Se 67%, Sp 93%, AUC 0.87) and from those with adenoma larger than 1cm (Se 63%, Sp 83%, AUC 0.77). In addition, the organ and disease specificity of these signatures was confirmed by means of patients with other cancer types and inflammatory bowel diseases.Conclusions: The two defined biomarker combinations effectively detect the presence of CRC and adenomas larger than 1 cm with high sensitivity and specificity. A prospective, multicentric, pivotal study is underway in order to validate these results in a larger cohort.