[Study on relationship of the K-ras mutation with the occurrence of colorectal liver metastasis and survival outcomes].

OBJECTIVE: To analyze the relationship of K-ras mutation with the development of liver metastasis in colorectal cancer patients and the survival outcomes. METHODS: From 2003 to 2008, 300 patients who underwent colorectal cancer surgery in the Department of General Surgery of Zhongshan Hospital, Fudan University were assigned to different groups, according to the diagnosis and follow-up results. The mutation of exon 2 of K-ras was detected in primary paraffin-embedded lesions by PCR and Pyrosequencing. The association of gene mutation with the development of liver metastasis and its prognosis was studied. RESULTS: Among 300 cases, the mutations of exon 2 were present in 120 cases(40%). The G13D mutation was more common in metachronous metastasis group than that in synchronous group(17.0% vs. 8.0%, P=0.041). Multivariable regression analysis showed that G13D mutation was an independent risk factor(HR=1.108, 95%CI:1.032-5.062, P=0.048) for metachronous metastasis. Patients with mutated K-ras had a poorer overall survival compared to those without mutated K-ras for patients without liver metastasis(median overall, 65 vs. 72 months, P=0.039), and for patients who received metastasis resection(median disease-free survival 18 vs. 24 months, P=0.048). Multivariable analysis showed that K-ras mutation was an independent risk factors of overall survival(HR=1.561, 95%CI:1.022-6.422, P=0.045) in patients without liver metastasis. CONCLUSION: Detection of K-ras mutation may predict the development of liver metastasis and prognosis.

[Application of enhanced recovery program after surgery(ERAS) in patients undergoing radical resection for colorectal cancer].

OBJECTIVE: To compare the enhanced recovery program after surgery (ERAS) with conventional perioperative management in patients undergoing radical resection for colorectal cancer. METHODS: The ERAS protocol included a combination of evidence-based and consensus methodology. A total of 597 consecutive patients undergoing elective colorectal resection were randomized to either the ERAS(n=299) or the control group(n=298). Outcomes related to nutrition and metabolism index, stress index, and recovery index were measured and recorded. RESULTS: Demographics and operative parameters were similar between the two groups(P>0.05). The nutritional status of patients in the ERAS group was improved after surgery compared with that of the control group. On postoperative day (POD) 1, the HOMA-IR in the ERAS group was significantly lower than that in the control group(P<0.01). The cortisol level in the control group was elevated on both POD 1(P<0.01) and POD 5(P<0.01) compared to the preoperative level. However, the cortisol level was not increased until POD 5(P<0.01) in the ERAS group. The levels of TNF-α, IL-1ß, IL-6, and IFN-γ were reduced in the ERAS group, indicating less postoperative stress responses compared with the control group. In addition, ERAS group was associated with accelerated recovery of gastrointestinal function. The postoperative length of stay [(5.7±1.6) d vs. (6.6±2.4) d, P<0.01] and expense[(15 998±2655) RMB vs. (17 763±3059) RMB, P<0.01] were reduced in the ERAS group. Twenty-eight patients(9.4%) in the control group and 29(9.7%) in the ERAS group developed complications, while the difference was not statistically significant(P>0.05). CONCLUSION: ERAS protocol alleviates surgical stress response and accelerates postoperative recovery without compromising patient safety.