Short-course radiotherapy in stage IV rectal cancer with resectable disease

Introduction Stage IV rectal cancer with resectable disease presents challenging issues, as the radical treatment of the whole disease is difficult. Surgery and chemotherapy (CT) play an unquestionable role, but the contribution of pelvic radiotherapy (RT) is not very clear. Methods In 2009, we established a prospective treatment protocol that included CT, short-course preoperative radiotherapy (SCRT) with surgery of the primary tumour and all metastatic locations. Results Forty patients were included. Eight (20%) patients did not receive CT due to significant comorbidities. Radical surgery treatment was possible in 22 (55%) patients. The mean follow-up was 42.81 months (3.63–105.97). Overall survival at 24 and 36 months was 71.4% and 58.2%, respectively. There was good local control of the disease, as 97.2% of pelvic surgeries were R0 and there were no local recurrences. Conclusion In stage IV with resectable metastatic disease, the proposed therapeutic regimen seems very appropriate in well selected patients able to tolerate the treatment. We bet on the role of pelvic RT, due to the good local control of the disease in our series (AU)

Short-course radiotherapy in stage IV rectal cancer with resectable disease.

INTRODUCTION: Stage IV rectal cancer with resectable disease presents challenging issues, as the radical treatment of the whole disease is difficult. Surgery and chemotherapy (CT) play an unquestionable role, but the contribution of pelvic radiotherapy (RT) is not very clear. METHODS: In 2009, we established a prospective treatment protocol that included CT, short-course preoperative radiotherapy (SCRT) with surgery of the primary tumour and all metastatic locations. RESULTS: Forty patients were included. Eight (20%) patients did not receive CT due to significant comorbidities. Radical surgery treatment was possible in 22 (55%) patients. The mean follow-up was 42.81 months (3.63-105.97). Overall survival at 24 and 36 months was 71.4% and 58.2%, respectively. There was good local control of the disease, as 97.2% of pelvic surgeries were R0 and there were no local recurrences. CONCLUSION: In stage IV with resectable metastatic disease, the proposed therapeutic regimen seems very appropriate in well selected patients able to tolerate the treatment. We bet on the role of pelvic RT, due to the good local control of the disease in our series.

Short-Course Radiotherapy in Locally Advanced Rectal Cancer.

INTRODUCTION: To date, we do not know the best therapeutic scheme in locally advanced rectal cancer when patients are older or have comorbidities. METHODS: In 2009, we established a prospective treatment protocol that included short-course preoperative radiotherapy (RT) with standard surgery +/- chemotherapy in frail patients, mostly older than 80 years or with comorbidities. RESULTS: We included 87 patients; the mean follow-up was 43.5 months (0.66-106.3). Disease-specific survival and disease-free survival at 36 months were 86.3% and 82.8%; at 60 months, they were 78.2% and 78%, respectively, with a local recurrence rate of 2.5%. The rate of late radiotoxicity was 9% in the form of sacral insufficiency fracture and small bowel obstruction with one death. The interval before surgery varied according to the involvement of the mesorectal fascia, but it was less than 2 weeks in 45% of cases. The rate of R0 was 95%. Surgical complications included abdominal wound dehiscence (3.5%), anastomotic leak (2.4%), and reoperations (11.5%). Downstaging was observed in 51% of the cases, regardless of the interval before surgery. DISCUSSION: Therapeutic outcomes in our group of elderly patients and/or patients with comorbidities with neoadjuvant short-course RT are such as those of the general population treated with neoadjuvant RT-chemotherapy, all with acceptable toxicity. Therefore, this treatment scheme, with short-course preoperative RT, would be the most appropriate in this group of patients.

Clinicopathological risk factors of Stage II colon cancer: results of a prospective study.

AIM: Adjuvant 5-fluorouracil based chemotherapy has demonstrated benefit in Stage III colon cancer but still remains controversial in Stage II. The aim of this study was to analyse the prognostic impact of clinicopathological factors that may help guide treatment decisions in Stage II colon cancer. METHOD: Between 1996 and 2006 data from patients diagnosed with colorectal cancer at Hospital Universitari Bellvitge and its referral comprehensive cancer centre Institut Català d'Oncologia/L'Hospitalet were prospectively included in a database. We identified 432 patients with Stage II colon cancer operated on at Hospital Universitari Bellvitge. The 5-year relapse-free survival (RFS) and colon-cancer-specific survival (CCSS) were determined. RESULTS: The 5-year RFS and CCSS were 83% and 88%, respectively. Lymphovascular or perineural invasion was associated with RFS [hazard ratio (HR) 1.84; 95% CI 1.01-3.35]. Gender (women, HR 0.48; 95% CI 0.23-1) and lymphovascular or perineural invasion (HR 3.51; 95% CI 1.86-6.64) together with pT4 (HR 2.79; 95% CI 1.44-5.41) influenced CCSS. In multivariate analysis pT4 and lymphovascular or perineural invasion remained significantly associated with CCSS. We performed a risk index with these factors with prognostic impact. Patients with pT4 tumours and lymphovascular or perineural invasion had a 5-year CCSS of 61%vs the 93% (HR 5.87; 95 CI 2.46-13.97) of those without any of these factors. CONCLUSION: pT4 and lymphatic, venous or perineural invasion are confirmed as significant prognostic factors in Stage II colon cancer and should be taken into account in the clinical validation process of new molecular prognostic factors.

Pharmacogenomics in colorectal cancer: a genome-wide association study to predict toxicity after 5-fluorouracil or FOLFOX administration.

The development of genotyping technologies has allowed for wider screening for inherited causes of variable outcomes following drug administration. We have performed a genome-wide association study (GWAS) on 221 colorectal cancer (CRC) patients that had been treated with 5-fluorouracil (5-FU), either alone or in combination with oxaliplatin (FOLFOX). A validation set of 791 patients was also studied. Seven SNPs (rs16857540, rs2465403, rs10876844, rs10784749, rs17626122, rs7325568 and rs4243761) showed evidence of association (pooled P-values 0.020, 9.426E-03, 0.010, 0.017, 0.042, 2.302E-04, 2.803E-03) with adverse drug reactions (ADRs). This is the first study to explore the genetic basis of inter-individual variation in toxicity responses to the administration of 5-FU or FOLFOX in CRC patients on a genome-wide scale.

Tools for protein-protein interaction network analysis in cancer research

As cancer is a complex disease, the representation of a malignant cell as a protein-protein interaction network (PPIN) and its subsequent analysis can provide insight into the behaviour of cancer cells and lead to the discovery of new biomarkers. The aim of this review is to help life-science researchers without previous computer programming skills to extract meaningful biological information from such networks, taking advantage of easy-to-use, public bioinformatics tools. It is structured in four parts: the first section describes the pipeline of consecutive steps from network construction to biological hypothesis generation. The second part provides a repository of public, user-friendly tools for network construction, visualisation and analysis. Two different and complementary approaches of network analysis are presented: the topological approach studies the network as a whole by means of structural graph theory, whereas the global approach divides the PPIN into sub-graphs, or modules. In section three, some concepts and tools regarding heterogeneous molecular data integration through a PPIN are described. Finally, the fourth part is an example of how to extract meaningful biological information from a colorectal cancer PPIN using some of the described tools (AU)

No association between germline allele-specific expression of TGFBR1 and colorectal cancer risk in Caucasian and Ashkenazi populations.

BACKGROUND: Germline allele-specific expression (ASE) of the TGFBR1 gene has been reported as a strong risk factor for colorectal cancer (CRC) with an odds ratio close to 9. Considering the potential implications of the finding, we undertook the task of validating the initial results in this study. METHODS: Allele-specific expression was measured using the highly quantitative and robust technique of pyrosequencing. Individuals from two different populations were studied, one Caucasian-dominated and the other of Ashkenazi Jewish descent, with different sources of non-tumoral genetic material in each. RESULTS: Our results showed no statistically significant differences in the degree of ASE between CRC patients and controls, considering ASE as either a quantitative or a binary trait. Using defined cutoff values to categorise ASE, 1.0% of blood lymphocytes from informative Israeli cases (total n=96) were ASE positive (median 1.00; range 0.76-1.31) and 2.2% of informative matched controls (total n=90) were ASE positive (median 1.00; range 0.76-1.87). Likewise, normal mucosae from Spanish patients (median 1.03; range: 0.68-1.43; n=75) did not show significant differences in the degree of ASE when compared with the Israeli patients or controls. CONCLUSIONS: Taken together, these results suggest that ASE of TGFBR1 does not confer an increased risk of CRC.

Polymorphisms in prostaglandin synthase 2/cyclooxygenase 2 (PTGS2/COX2) and risk of colorectal cancer.

Inflammation plays a key role in the development of colorectal cancers. We have investigated the relationship between PTGS2 (COX2) polymorphisms and colorectal cancer risk in a hospital based case-control study. We recruited 292 patients with colorectal cancer and 274 controls from new patients admitted to Bellvitge Hospital, Barcelona, Spain, from 1996 to 1998. Subjects responded to a questionnaire on risk factors. Genotypes of the eight more frequent polymorphisms of PTGS2 were determined. Two polymorphisms are located in the promoter sequence, one in the untranslated region of exon 1, one in exon 3, one in intron 5, two in the untranslated region of exon 10, and one downstream of the last polyadenylation (poly-A) signal. Associations were analysed with logistic regression models assuming a dominant effect for rare variants to increase statistical power. An association was detected between colorectal cancer and a polymorphism in the untranslated region of exon 10 of PTGS2, with an odds ratio (OR) of 2.49, 95% confidence interval (CI) of 1.17-5.32, P=0.01. A nearby polymorphism downstream of the last poly-A signal also showed a nonsignificant increase in risk (OR 2.17, 95% CI 0.99-4.78, P=0.05). Analysis of haplotypes confirmed that individuals with these variants were at increased risk of colorectal cancer (OR compared to the most frequent haplotype: 2.17, 95% CI 0.97-4.84, P=0.06) Interactions between PTGS2 genotype and use of nonsteroidal anti-inflammatory drugs and risk of colorectal cancer were also explored.