Serum hepatocyte growth factor as a prognostic marker for stage II or III colorectal cancer patients Yuji Toiyama * , Chikao Miki, Yasuhiro Inoue, Yoshinaga Okugawa, Kouji Tanaka and Masato Kusunoki Department of Gastrointestinal and Pediatric Surgery, Mie University Graduate School of Medicine, Tsu, Mie, Japan We previously reported that a combination of serum hepatocyte growth factor (HGF) and carcinoembryonic antigen (CEA) was useful for selecting early-stage colorectal cancer patients with aggressive disease. The aim of the present study was to determine whether serum HGF could provide CEA-independent prognostic information on patients undergoing surgery with curative intent. Serum samples were collected from 184 patients with colorectal cancer and 30 controls. Reverse-transcription polymerase chain reaction was used to detect HGF expression in colorectal cancer cell lines. Serum and tissue levels of HGF were measured by enzyme-linked immunosorbent assay. The serum HGF levels in colorectal cancer patients were compared with those in healthy controls, and we retrospectively assessed the association between serum HGF levels and clinicopathological findings and survival. Expression of HGF was significantly higher in colorectal cancer tissues compared with non-tumor tissues. The serum HGF levels were closely correlated with the HGF levels in cancer tissue. The mean serum HGF level in patients was significantly higher than that in controls, and significantly higher in patients with large tu- mor, lymph-node involvement and distant metastasis. According to the receiver operating characteristic (ROC) analysis, elevated serum HGF levels can predict patients with larger tumor, lymph- node and distant metastasis. Elevated serum HGF level demon- strated a significant association with poor survival, and was only an independent risk factor for poor survival in Stage II or/and III. Elevated serum HGF level is significantly associated with colorec- tal cancer development, lymph or distant invasive phenotypes and survival, especially in Stage II or III patients. ' 2009 UICC Key words: colorectal cancer; HGF; CEA; prognostic factor; stage II; stage III Colorectal cancer remains the most common malignant disease worldwide, and after potential curative surgery, 30% of the patients will eventually develop metastases, often in spite of adju- vant therapies, such as chemotherapy and radiochemotherapy. 1 Although adjuvant chemotherapy provides significant survival benefit in Stage III patients, it is controversial whether this treat- ment has any effect on patients with Stage II colon cancer, 20– 30% of whom eventually experience tumor relapses. 2 Adjuvant chemotherapy was shown to increase the survival of certain popu- lations of Stage II patients 3 ; furthermore, almost 60% of Stage III patients were not relapsing, even if adjuvant chemotherapy was not received. 4 Therefore, identification of high-risk patients among Stage II and III colorectal cancer patients would be of great benefit in selecting appropriate candidates for standard or intense adjuvant therapy. Carcinoembryonic antigen (CEA) is a complex glycoprotein that is upregulated in 90% of advanced colorectal cancers and contributes to the malignant characteristics of tumors. 5 However, it is not useful in detecting asymptomatic cancer, because the sen- sitivity of CEA determination for early colorectal cancer is as low as 30–40%. 6 Moreover, CEA is not significantly associated with survival among patients with Stage I and II lesions, and CEA test- ing is relatively insensitive to tumors with local or peritoneal involvement. 7 Hepatocyte growth factor (HGF) is a mesenchymal cytokine with a number of biological activities, including mitogenic, moto- genic and/or morphogenic properties, in a variety of epithelial tissues. HGF is also a known angiogenesis factor that promotes endothelial cell growth, survival and migration, both in vitro and in vivo. 8,9 A relationship between the concentration of HGF in the serum or cancer tissue of cancer patients and the progression of disease has been reported. This relationship is seen in patients with breast, gastric, bladder, prostate, lung cancers and colorectal cancer. 10–14 Previously, we reported preliminary data on serum HGF levels in patients with colorectal cancer, and found that these were elevated in a significant population of the patients, reflecting not only disease progression, but also an association between the host’s nutritional and immunologic conditions. 15 Recently, we reported that HGF and CEA tests provided more information than CEA alone for prognosis in Stage I and II patients. 16 In the current study, we further assessed a possible role for pre- operative serum HGF as a potent predictor of prognosis in color- ectal cancer patients undergoing surgery with curative intent. The incentive for this work was that a new biomarker would be of more benefit to specific subgroups of patients, namely Stage II and III patients, than the existing systems and serum tumor markers such as CEA. Material and methods Patients One hundred eighty-four patients who underwent resection of colorectal carcinoma at our institution between January 1996 and January 2002 were enrolled in this retrospective study. The patients included 111 men and 73 women with a mean age of 64 (range, 27–86) years. The locations of the tumors and distant me- tastases were determined by barium enemas, colonoscopies, com- puterized tomography (CT) and magnetic resonance imaging (MRI). The primary lesion was located in the rectum in 68 patients, the sigmoid colon in 64, the ascending colon in 35, the transverse colon in 9, and the descending colon in 7. Twenty-nine patients were diagnosed as having synchronous liver metastasis and 3 patients were diagnosed with both liver metastases and peri- toneal dissemination. Tumor resection was performed on all patients and simultaneous partial hepatectomy for liver metastasis was performed on 15. No peri-operative mortalities were observed among these patients. Seventeen patients had a poorly differenti- ated adenocarcinoma, whereas, in 167 patients, the adenocarci- noma was well or moderately differentiated. All patients were classified according to UICC stage classifications using resected specimens. There were 20 patients with Stage I disease, 75 patients with Stage II disease and 60 patients with Stage III dis- ease. Twenty-nine patients with distant metastases were classified as having Stage IV disease. Stage III and IV patients received fluo- rouracil-based chemotherapy, whereas, in Stage I and II patients, no adjuvant therapy was applied postoperatively. Patients were observed at 3-month intervals for 24 months after the completion of surgery, then every 6 months for 3 years, and then yearly. A history was taken and physical examination was performed at *Correspondence to: Department of Gastrointestinal and Pediatric Sur- gery, Mie University Graduate School of Medicine, Tsu, Mie, Japan. Fax: 181-59-232-6968. E-mail: ytoi0725@clin.medic.mie-u.ac.jp Received 25 November 2008; Accepted after revision 27 April 2009 DOI 10.1002/ijc.24554 Published online 4 May 2009 in Wiley InterScience (www.interscience. wiley.com). Int. J. Cancer: 125, 1657–1662 (2009) ' 2009 UICC Publication of the International Union Against Cancer