Expression and clinical significance of IGF-1 and LP in serum of colorectal cancer patients

Objective To detect the expression levels of insulin-like growth factor 1 (IGF-1) and leptin (LP) in serum of patients with colorectal cancer, and to analyze its clinical significance. Methods Seventy-three patients with colorectal cancer, 37 patients with benign colorectal cancer and 40 healthy subjects were enrolled. Serum IGF-1 and LP levels of all the subjects were measured. A two-year follow-up study of colorectal patients was performed to observe the occurrence of lymph node metastasis. Logistic regression was used to analyze the factors affecting lymph node metastasis in colorectal cancer patients. The area under the receiver operating characteristic curve (AUC) was used to analyze the diagnostic value of IGF-1 and LP for colorectal cancer and recurrence. Results The serum IGF-1 concentration in colorectal cancer was significantly lower than that in the control group (P 0.05). The serum LP level of colorectal cancer was significantly higher than that of benign lesions and control group (P<0.05). Both IGF-1 and LP have certain diagnostic value for colorectal cancer, and the combined test and efficacy of the two methods are higher than those of the separate test (P<0.05). The two-year recurrence rate of colorectal cancer patients was 16.43%, and the patient age (≥40 years old), TNM grade (Ⅲ~Ⅳ grade), tumor diameter (≥4 cm), vascular infiltration and deep muscle infiltration in the recurrent patients were significantly higher than that in the untreated patients (all P<0.05). In the cancer metastasis patients, the level of serum IGF-1 and LP was significantly lower and higher than that in non-metastatic patients, respectively (all P<0.05). Vascular infiltration, deep myometrial invasion, low IGF-1 levels, and high LP levels were independent predictors of recurrence in colorectal cancer patients, and the combined predictive AUC of the above four factors was 0.956 (95%CI: 0.988 1~0.990). Conclusions In patients with colorectal cancer, IGF-1 level is low and LP level is high, which is closely related to cancer recurrence. Key words: Insulin-like growth factor; Leptin; Colorectal cancer; Risk factors; Diagnosis