Analysis of gene expression EGFR and KRAS, microRNA-21 and microRNA-203 in patients with colon and rectal cancer and correlation with clinical outcome and prognostic factors

Purpose: To evaluate the expression of EGFR, KRAS genes, microRNAs-21 and 203 in colon and rectal cancer samples, correlated with their age at diagnosis, histological subtype, value of pretreatment CEA, TNM staging and clinical outcome. Methods: Expression of genes and microRNAs by real time PCR in tumor and non-tumor samples obtained from surgical treatment of 50 patients. Results: An increased expression of microRNAs-21 and 203 in tumor samples in relation to non-tumor samples was found. There was no statistically significant difference between the expression of these genes and microRNAs when compared to age at diagnosis and histological subtype. The EGFR gene showed higher expression in relation to the value of CEA diagnosis. The expression of microRNA-203 was progressively lower in relation to the TNM staging and was higher in the patient group in clinical remission. Conclusions: The therapy of colon and rectum tumors based on microRNAs remains under investigation reserving huge potential for future applications and clinical interventions in conjunction with existing therapies. We expect, based on the exposed data, to stimulate the development of new therapeutic possibilities, making the treatment of these tumors more effective.(AU)

Serological under expression of microRNA-21, microRNA-34a and microRNA-126 in colorectal cancer

PURPOSE: This paper describes the ability of miRNA value predict oncological outcomes in CRC patients and correlates to clinical and pathologic variables. METHODS: We prospectively analyzed the serological expression of microRNA-21, microRNA-34a, and microRNA-126 in 37 stage II - IV CRC patients and correlate to seven fit counterparts. Serological microRNAs were extracted using the miRNeasy Mini Kit(r) (Qiagen, Hilden, Germany). Quantification of microRNAs was performed using TaqMan Master Mix(r) reagent (Applied Biosystems, USA). RESULTS: We obtained serological underexpression microRNA-21, microRNA-34a, and microRNA-126 in CRC group. However, miRNAs serological values do not impact prognosis. Furthermore, miRNAs was not influenced by CEA values, TNM staging, and histological subtype. CONCLUSION: Despite lower expression of miR-21, miR-34a and miR-126 in the CRC group, no association with poor prognosis was found.(AU)

Transanal endoscopic operation for rectal cancer after neoadjuvant therapy

PURPOSE: In this paper we report the oncological outcomes from clinical series of patients with rectal cancer submitted to local excision after neoadjuvant therapy and discuss the indications for local excision in partial clinical responders. METHODS: We analysed a prospective database of 39 patients submitted to a transanal endoscopic operation for rectal cancer after neoadjuvant chemoradiation between 2006 and 2015, comparing clinical and pathological variables, perioperative complications, recurrence rate and overall survival. RESULTS: We obtained 15.4% ypT0, 17.9% ypT1, 35.9% ypT2 and 28.2% ypT3. After a median follow-up of 24 months, tumoral recurrence was observed in 4 patients, one of them with isolated pulmonary metastasis. R0 resection was achieved in 79.5%, and postoperative complications were observed in 30.2% patients and no perioperative mortality occur. Compromise surgical margins do not affect recurrence rate, and 94.9% of patients are alive nowadays. CONCLUSION: Local excision could be associated with low recurrence rate and good overall survival. Short hospitalization time and low level of serious complications observed could be an interesting option for patients who would not tolerate a radical procedure or for those who declined a total mesorectal excision. A strict long-term follow-up must be warranted to detect early tumoral recurrence.(AU)

Comparative evaluation of oncologic outcomes in colon cancer

PURPOSE: In this paper we report clinical variables on colon cancer series. Oncological outcomes were compared to low-income and high-income countries. METHODS: We analysed a prospective database of 51 colon cancer patients submitted to primary tumor resection between 2010 and 2011, showing clinical variables and oncologic outcomes. RESULTS: R0 resection obtained in 80.4%, 21.6% of patients was TNM stage IV, and only 13.7% showed TNM stage I. Disease-free survival was 32 months, overall survival was 46 months, and the tumoral recurrence rate was 9.8%. Univariate analysis showed association of serum CEA levels 5 ng/dl (p= 0.004), presence of metastasis at diagnosis (p= 0.012), compromised surgical margins (p 0.001) and poorer tumor differentiation (p= 0.041) to death. Multivariate analysis identified compromised surgical margins as an independent risk factor for death due to colon cancer (P=0.003; odds ratio=0.36; 95% confidence interval=0.004-0.33). Nowadays, 62.7% of patients are alive. CONCLUSION: Recurrence rate, disease-free survival and overall survival was similar to those observed in more developed countries. Serum CEA levels 5 ng/dl, the presence of metastasis at diagnosis, compromised surgical margins and poorer tumor differentiation were associated with death. A compromised surgical margin was the only independent risk factor for death.(AU)