Circulating transforming growth factor beta 1 as a predictor of liver metastasis after resection in colorectal cancer

Plasma transforming growth factor pi (TGF-beta1) has been reported to be co rrelated with the extent of disease in colorectal cancer, but it is not kno wn whether measuring this cytokine can help predict liver metastasis after curative resection, We prospectively studied whether plasma TGF-BI levels c ould predict liver metastasis in 117 patients with colorectal cancer before and after curative resection, Blood samples were drawn before and 2 weeks after surgery to determine the cytokine levels. Abdominal ultrasonography o r computed tomography was done every 3 months after surgery. The primary en d point for follow-up was recurrence. Seventy-seven of 117 cases (66%) had preoperative levels of the cytokine higher than the borderline limit of 7.5 ng/ml, Postoperative levels were >7.5 ng/ml in 29 of 117 patients (25%), T he median follow-up period was 42 months (range, 5-66 months), with follow- up of all 117 patients, No recurrence was observed in 13 patients with Duke s' stage A lesions. Liver metastasis occurred in 18 of 104 patients (17%) w ith Dukes' stage B or C disease, Fourteen of 18 patients (78%) who develope d liver metastasis had shown a postoperative plasma TGF-beta1 level of >7.5 ng/ml. Cox proportional hazards regression analysis showed that the postop erative level was a significant predictive factor for liver metastasis (P < 0.001). A single point measurement of plasma TGF-beta1 levels at 2 weeks a fter curative resection seems to be able to predict liver metastasis in col orectal cancer. This finding sugests the value of a prospective trial of fi ver-targeted adjuvant therapy for patients with elevated postoperative plas ma TGF-beta1 levels.