Relationship of radiometabolic biomarkers to KRAS mutation status and ALK rearrangements in cases of lung adenocarcinoma.

PURPOSE: Rapid diagnosis of genetic mutations is important for targeted therapies such as EGFR tyrosine kinase inhibitors. KRAS mutation and ALK rearrangement are also important in determining treatment. The purpose of our study was to evaluate the diagnostic value of 18F-FDG PET to predict KRAS mutation and ALK rearrangement in order to determine the frequency of these genetic markers in our lung adenocarcinoma cases and contribute to forthcoming meta-analysis studies. METHODS: A total of 218 patients with lung adenocarcinoma (EGFR analyzed) who were seen at our clinic between 2012 and 2014 were included in the study. The results of the 18 F-FDG-PET scans for each patient were retrospectively recorded with the associated medical documents. ALK rearrangements were analyzed in 166 of the 218 patients, while 50 of the 218 patients were analyzed for KRAS mutational status. SPSS 15.0 for Windows was used for statistical analysis. RESULTS: FDG avidity was higher in cases with KRAS mutations and ALK rearrangements than those without, but the difference was not significant. ALK rearrangements were more common in younger, female, and nonsmoking patients with lung adenocarcinoma. CONCLUSIONS: The small numbers of KRAS mutations and ALK rearrangements are the limitation of this study for evaluation of diagnostic imaging. The frequency of these genetic alterations was as reported in the literature. We believe that our work will contribute to future meta-analysis.

Serum vascular endothelial growth factor receptor-3 levels in patients with esophageal squamous cell cancer.

AIM: Esophageal cancer is one of the most aggressive tumors of the gastrointestinal tract. In this study, we quantified the serum vascular endothelial growth factor-3 (VEGFR-3) expression in patients with esophageal squamous cell carcinoma (ESCC) to evaluate the role of VEGFR-3 in ESCC. MATERIALS AND METHODS: Ninety five patients with ESCC were studied. Pre-therapy and preoperative samples were stored and ELISA was used to designate the concentrations of VEGFR-3. RESULTS: The serum values of VEGFR-3 were significantly higher in patients with ESCC than in healthy donors (p<0.0001). CONCLUSIONS: The results imply a very good sensitivity of VEGFR-3 in ESCC. VEGFR-3 may be a good diagnostic biomarker for ESCC. KEY WORDS: Biomarker, ESCC, VEGFR-3.

Relationship of Radiometabolic Biomarkers to KRAS Mutation Status and ALK Rearrangements in Cases of Lung Adenocarcinoma.

Purpose Rapid diagnosis of genetic mutations is important for targeted therapies such as EGFR tyrosine kinase inhibitors. KRAS mutation and ALK rearrangement are also important in determining treatment. The purpose of our study was to evaluate the diagnostic value of 18F-FDG PET to predict KRAS mutation and ALK rearrangement in order to determine the frequency of these genetic markers in our lung adenocarcinoma cases and contribute to forthcoming meta-analysis studies. Methods A total of 218 patients with lung adenocarcinoma (EGFR analyzed) who were seen at our clinic between 2012 and 2014 were included in the study. The results of the 18 F-FDG-PET scans for each patient were retrospectively recorded with the associated medical documents. ALK rearrangements were analyzed in 166 of the 218 patients, while 50 of the 218 patients were analyzed for KRAS mutational status. SPSS 15.0 for Windows was used for statistical analysis. Results FDG avidity was higher in cases with KRAS mutations and ALK rearrangements than those without, but the difference was not significant. ALK rearrangements were more common in younger, female, and nonsmoking patients with lung adenocarcinoma. Conclusions The small numbers of KRAS mutations and ALK rearrangements are the limitation of this study for evaluation of diagnostic imaging. The frequency of these genetic alterations was as reported in the literature. We believe that our work will contribute to future meta-analysis.

Effects of mesenchymal stem cells and VEGF on liver regeneration following major resection.

PURPOSE: The study aims to determine the effects of mesenchymal stem cell (MSC) therapy and a combination therapy of MSCs transfected with vascular endothelial growth factor (VEGF) for liver regeneration after major resection. METHODS: Thirty-eight rats were divided into four groups: group 1: control (sham operation); group 2: control (70 % hepatic resection); group 3: 70 % hepatic resection + systemically transplanted MSCs; and group 4: 70 % hepatic resection + systemically transplanted MSCs transfected with the VEGF gene. MSCs were injected via the portal vein route in study groups 3 and 4. Expression levels of VEGF, fibroblast growth factor (FGF), platelet-derived growth factor (PDGF), epidermal growth factor (EGF), transforming growth factor (TGF), hepatocyte growth factor (HGF), and augmenter of liver regeneration (ALR) were analyzed in the remnant liver tissue. We investigated the levels of angiogenic factors, VEGF-receptor, angiopoietin-1 (Angpt1) and Angpt2. Biochemical parameters of liver function in blood samples were measured and a histologic assessment of the livers was performed. The postoperative liver weight and volume of each rat were measured 14 days after surgery. RESULTS: The expression levels of all measured growth factors were significantly increased in groups 3 and 4 compared to the control groups. The levels of Angpt1 and Angpt2 correlated with levels of VEGF and thus were also significantly higher in the study groups. There were significant differences between the estimated liver weights and volumes of group 4 and the resected controls in group 2. With the exception of portal inflammation, levels of all histological parameters were observed to be higher in MSC-treated groups when compared with the resected controls in group 2. CONCLUSIONS: Transplanted stem cells and MSCs transfected with VEGF significantly accelerated many parameters of the healing process following major hepatic resection. After the injection of MSCs and VEGF-transfected MSCs into the portal vein following liver resection, they were engrafted in the liver. They increased bile duct and liver hepatocyte proliferation, and secreted many growth factors including HGF, TGFß, VEGF, PDGF, EGF, and FGF via paracrine effects. These effects support liver function, regeneration, and liver volume/weight.

Effect of hyperbaric oxygen treatment on pilonidal disease surgery.

Surgical excision and lay-open is a well-known technique for the treatment of sacrococcygeal pilonidal disease, which impairs a patient's quality of life considerably since wound healing takes a substantial amount of time. It is known that with this method total healing period is longer, but recurrence rate of the disease is lower. The beneficial effects of hyperbaric oxygen (HBO2) therapy on wound healing have been well established since it was first put into in clinical use. The purpose of this prospective randomized clinical trial was to investigate the effects of HBO2 therapy on wound healing in the patients who had sacrococcygeal pilonidal disease and surgical treatment. Total epithelialization times of 12 patients (Group 1) who received surgical intervention were compared with those of 10 patients who had surgical intervention and HBO2 therapy (Group 2). In both groups excised tissue volume, excised skin area, body mass index, blood hemoglobin, albumin levels, ages and duration of the complaints were recorded and there was no statistically significant difference in these parameters except albumin levels when compared. The complete epithelialization time was significantly shorter in Group 2 (50 ± 11 vs. 83 ± 18, p⟨0.001). We conclude that HBO2 had beneficial effects on wound healing, in the patients who had sacrococcygeal pilonidal disease and were treated with surgical excision applying lay-open technique.

Does Metastatic Lymph Node SUVmax Predict Survival in Patients with Esophageal Cancer?

OBJECTIVE: We aimed to investigate the SUVmax of primary tumor and metastatic lymph node in predicting survival in patients with esophageal cancer. METHODS: We retrospectively analyzed patients with esophageal cancer between 2009 and 2011 who had FDG positron-emission tomography (PET)/computed tomography (CT). All patients were followed-up to 2013. Clinical staging, SUVmax of primary tumor and metastatic lymph node were evaluated. RESULTS: One hundred seven patients were included in the study. All patients were followed-up between 2 and 49 months. The mean SUVmax of primary tumor and metastatic lymph node were 19.3±8.8 and 10.4±9.1, respectively. Metastatic lymph node SUVmax had an effect in predicting survival whereas primary tumor SUVmax did not have an effect (p=0.014 and p=0.262, respectively). Multivariate Cox regression analysis showed that clinical stage of the disease was the only independent factor predicting survival (p=0.001). CONCLUSION: Among patients with esophageal cancer, the value of primary tumor SUVmax did not have an effect on survival. Clinical stage assessed with FDG PET/CT imaging was found to predict survival in esophageal carcinoma. Additionally, lymph node SUVmax was identified as a new parameter in predicting survival in the present study.

Preoperative serum levels of mesothelin in patients with colon cancer.

BACKGROUND: Screening for biochemical markers is important for diagnosing colon cancer. In this study, the reliability of serum mesothelin levels as a potential diagnostic and screening instrument was evaluated concerning colon cancer. METHODS: Ninety-five patients who had undergone colonoscopic examination and who were diagnosed with colon cancer were included in the study. The serum mesothelin levels were measured with the ELISA kits and were evaluated in terms of significant difference when compared between colon cancer and control group. RESULTS: Patients with colon cancer had significantly higher mesothelin serum levels (P < 0.001) than the control groups. We found significant associations between serum levels and tumor grade, perineural invasion, and vascular invasion (resp., P < 0.001). CONCLUSION: Evaluating the serum levels of mesothelin has a potential to detect and screen the colon cancer in affected patients. Our data suggest that mesothelin exhibits effects towards colon cancer and serves as a biomarker for this deadly disease.

The assessment of high sensitivity C-reactive protein as a systemic marker in moderate asthma patients and changing levels by inhaled corticosteroids.

OBJECTIVES: To see if high-sensitivity C-reactive protein levels increase even in the early stages of asthma, and to evaluate if corticosteroid therapy affects the levels in asthma patients. METHODS: The case-control pilot study was conducted at Yedikule Chest Disease and Surgery Education and Research Hospital, Turkey, from February to April 2011. Patients newly diagnosed with asthma who reported symptoms that occurred six months before diagnosis were included in the study.The protein levels were measured pre-treatment and one month post-treatment. In addition, pulmonary function test and total Immunoglobulin-E measurements were taken and the prick test was performed. Statistical analysis was done using SPSS 15. RESULTS: There were 15 cases; 8 (53%) females and 7 (47%) males. Besides, there were 19 Controls; 9 (47%) females and 10 (53%) males. The mean age of the Cases was 29.13+/-10.30 years, while for the Controls it was 28.9+/-5.35 years. The difference was not statistically significant (p<0.54). The difference in protein levels pre and post-treatment was not significant. However, a higher level in the pre-treatment period was found compared to the Controls. Posttreatment levels in the Cases were not significantly different than the Controls. CONCLUSION: Elevated high-sensitivity C-reactive protein levels in asthmatic patients may indicate an increased risk for cardiovascular disease. Future studies in asthma patients should focus on this relationship.

Immunohistochemical expression of telomerase in patients with non-small cell lung cancer: prediction of metastasis and prognostic significance.

AIM: To detect telomerase reverse transcriptase (TERT) expression in tissue and metastatic and non-metastatic lymph node samples from patients with non-small cell lung cancer; to evaluate whether TERT expression is correlated with pathological and clinical features, and/or patient survival times; to determine differences between TERT expression in metastatic and non-metastatic lymph nodes. PATIENTS AND METHODS: Tumor tissue samples from 17 patients with squamous cell lung cancer and 11 patients with adenocarcinoma diagnosed between 2003 and 2004 were included in this study. All patients were diagnosed at our hospital and had samples stored in the pathology archive. Additionally, dissected lymph node samples, with and without metastases, were studied. Telomerase Gene Tex, Inc, Irvine, CA USA (TERT (2C4) antibody), Universal Kit (Lab Vision, Newmarket, UK) were used for immunohistochemical staining. Statistical analyses were performed using SPSS 17.0 statistical software. RESULTS: TERT was positive in 18/28 of the samples, regardless of the histological tumor type. There was no significant correlation between TERT expression in lymph nodes with metastasis and clinical stage, histological type, tumor differentiation, or survival time. CONCLUSION: TERT expression may be used as a target for therapy. It may also be helpful in predicting metastasis but not in predicting survival time.

Comparison of phenol matricectomy and nail-splinting with a flexible tube for the treatment of ingrown toenails.

BACKGROUND: The treatment of ingrown toenail is usually bothersome for patients and doctors. OBJECTIVES: To compare two treatment techniques of ingrown toenails-phenol matricectomy (PM) and nail-splinting using a flexible tube (FT)-in terms of efficacy, postoperative pain, postoperative cosmetic satisfaction, amount of tissue damage, and recurrence. METHODS AND MATERIALS: One hundred twenty ingrown toenails were randomized and divided into PM and FT groups. All cases were evaluated 2 days and 1 and 6 months after treatment. Postoperative pain, cosmetic satisfaction, time to recovery, and recurrence rate were measured. RESULTS: Postoperative pain was less and cosmetic satisfaction was good in both groups (p <.001). Our recurrence rate was 8.4%. There were no statistical differences between groups in these measures. Tissue improvement rate was 6% in the PM group and 93% in the FT group 2 days after the procedures (p <.001). CONCLUSIONS: Although FT provides faster recovery and less postoperative morbidity than PM, the techniques are equally effective in treating ingrown toenails.

Could serum ß-hCG levels and gestational age be the indicative factors for the prediction of the degree of trophoblastic invasion into tubal wall in unruptured ampullary pregnancies?

OBJECTIVE: To evaluate the predictive value of gestational age and maternal serum ß-hCG concentration for the determination of the depth of trophoblastic invasion into the tubal wall. METHODS: This is a retrospective trial conducted on women with a diagnosis of ampullary pregnancy (71) who were submitted to salpingectomy. Serum ß-hCG measurements were obtained at the initial admission of hospital. Histological investigation was performed by a single well-experienced pathologist who was blind to the clinical and laboratory characteristics of the patients. Ampullary pregnancy was classified histologically according to the depth of trophoblastic infiltration into tubal wall: trophoblast limited to the tubal mucosa (stage I), extended to muscularis layer (stage II) and complete tubal wall infiltration up to serosal layer (stage III). RESULTS: There was a significant difference in maternal serum ß-hCG concentrations regarding the histological stages of trophoblastic invasion. The serum ß-hCG concentrations that the best predicted for stage III trophoblastic invasion was 6,475 mIU/ml, with a sensitivity of 100 %, a specificity of 92 %. CONCLUSION: The depth of trophoblastic tissue infiltration into tubal wall is correlated with serum ß-hCG levels, but not with gestational age. These findings may explain the reason for conservative management failure of EP in women with high ß-hCG concentrations.

Plasma human neutrophil proteins-1, -2, and -3 levels in patients with bladder cancer.

OBJECTIVES: Human neutrophil proteins-1, -2, and -3 (HNPs -1, -2, and -3) are expressed in several tumor types. However, the role of HNPs 1-3 in human bladder cancer has not yet been determined. We investigated the association between the plasma levels of HNPs 1-3 and clinicopathological parameters in bladder cancer patients. DESIGN AND METHODS: The plasma levels of HNPs 1-3 were measured in 60 patients with bladder cancer and in 58 healthy controls. The plasma levels of HNPs 1-3 were determined by a solid-phase enzyme-linked immunosorbent assay (ELISA). Plasma samples were obtained before surgery. Plasma samples were permitted to clot and were then stored at -80 °C until use. RESULTS: The levels of the HNPs increased from grade 1 to 4 tumors and this difference was statistically significant (p < 0.001). Additionally, plasma HNP levels were significantly higher in patients with metastatic bladder cancer and in patients with lymphovascular involvement, metastasis of the lymph nodes, and increased tumor burden (p < 0.001). CONCLUSIONS: The preoperative plasma levels of HNPs 1-3 paralleled the progression and pathological stages of the malignancies. This study suggests that HNPs 1-3 promote tumor invasion and are potential indicators of disease progression in patients with bladder cancer.

Differences in Mucociliary activity of volunteers undergoing Ramadan versus Nineveh fasting.

This study, aimed to evaluate the difference in mucociliary clearance among volunteers who underwent Ramadan versus Nineveh fasting regimens as well as the difference between the fasting period and 4 weeks following the fasting period in both groups. In this study, two different fasting groups were established: Ramadan (fasting for an average of 15 h for 29 consecutive days, n = 40) and Nineveh (60 h of nonstop fasting, n = 26). Subjects in each group underwent saccharin testing twice: at the end of the fasting period prior to resumption of eating and at 4 weeks after the end of Ramadan or Nineveh fasting. Statistical analysis was performed using the Mann-Whitney U-test, Wilcoxon, Chi-square, and paired t test. A p value less than 0.05 was considered statistically significant. Forty subjects who underwent Ramadan fasting and 26 subjects who underwent Nineveh fasting were included in this study. Of the 66 study participants, 34 (51.5 %) were men and 32 (48.5 %) were women. Their median age was 31 years (range 17-70 years) for Nineveh fasting subjects and 40 years (range 17-70 years) for Ramadan fasting subjects. Chi-square tests revealed no significant difference between the Ramadan and Nineveh fasting groups in gender (p = 0.418), and the Mann-Whitney U-test showed no difference in age. A statistically significant difference was found in the mucociliary clearance time between the Nineveh fasting and non-fasting periods (p = 0.013). Using Wilcoxon signed-rank tests, we found no significant difference in the mucociliary clearance time between the Ramadan fasting and control (4 weeks after the fasting period) periods (p = 0.121). The percentage difference between the fasting and control periods was similar between groups and was not statistically significant for the Ramadan and Nineveh fasting groups (p = 0.086). The results of the present study indicated that long-term fasting with hypohydration contributed to the deterioration of nasal mucociliary clearance. Our data indicate that optimal hydration, sleep patterns, and fasting times contribute to proper mucociliary clearance.

Alpha-1 protease inhibitor and antichymotrypsin levels in acute pancreatitis.

BACKGROUND: Acute pancreatitis with high mortality of severe onset is still a major problem in medicine. Early identification of the severity of the disease is critical for effective treatment. Many markers have been tried and are still being tested. The ideal marker should be able to identify the cases and distinguish between mild and severe. METHODS: This prospective study included 34 cases (14 males, 20 females, mean age: 58 years) of acute pancreatitis and 33 cases (17 males, 16 females, mean age: 53 years) as a control group. Mild (n=29) and severe (n=5) cases were compared with respect to serum levels of amylase, C-reactive protein (CRP), alpha-1-protease inhibitor, and antichymotrypsin on admission and 24 and 48 hours (h) after admission. RESULTS: Alpha-1 protease inhibitor and antichymotrypsin levels were significantly elevated in the first 24 h; however, CRP peaked after 48 h in the acute pancreatitis group. While CRP showed significantly higher concentrations in patients with severe pancreatitis, alpha-1-protease inhibitor and antichymotrypsin levels changed slightly, but without significance, in severe cases. CONCLUSION: Alpha-1 protease inhibitor and antichymotrypsin are early events in acute pancreatitis, with high levels on admission. Activation of these variables declines after 24 h. These markers may have early diagnostic value in patients with acute pancreatitis. Because neither of them is good at discrimination of mild and severe cases in the disease, they should not be incorporated into routine clinical investigations.

Preoperative serum placenta growth factor level as a new marker for stage II or III colorectal cancer patients.

BACKGROUND/AIMS: We first reported in this study that serum placenta growth factor and carcinoembryonic antigen in combination were useful markers for selecting early-stage colorectal cancer patients. The aim of the present study was to determine whether serum placenta growth factor could provide carcinoembryonic antigen-independent prognostic information on patients undergoing curative surgery. METHODS: Serum and tissue samples were collected from 158 patients with colorectal cancer and from 50 controls. Serum and tissue levels of placenta growth factor were measured by enzyme-linked immunosorbent assay. The serum placenta growth factor levels in colorectal cancer patients were compared with those in healthy controls, and we retrospectively assessed the association between serum placenta growth factor levels and clinicopathological findings and survival. RESULTS: Expression of placenta growth factor was significantly higher in colorectal cancer tissues compared with non-tumor tissues. The mean serum placenta growth factor level in patients was significantly higher than that in controls and significantly higher in patients with large tumor, lymph-node involvement and distant metastasis. CONCLUSIONS: Elevated serum placenta growth factor levels are significantly associated with colorectal cancer development, lymph or distant invasive phenotypes and survival, especially in stage II or III patients.

Relationship between the levels of oxidative stress in mesenteric and peripheral serum and clinicopathological variables in colorectal cancer.

OBJECTIVE: To explore the differences existing between the levels of oxidative stress in peripheral and mesenteric serum in patients with colorectal cancer. MATERIAL AND METHODS: One hundred fifty patients with colorectal cancer who underwent surgery between May 2005 and March 2010 were prospectively analyzed. The differences between oxidative stress parameters in their peripheral and mesenteric blood were measured. The associations between peripheral and mesenteric levels and the staging and clinicopathological variables were investigated. RESULTS: Oxidative stress parameters were higher in patients with advanced tumor staging (p<0.01), lymph node invasion (p<0.01), and venous invasion (p<0.01). Differences between oxidative stress parameters in peripheral and mesenteric blood samples were also observed. CONCLUSIONS: The mesenteric levels of the oxidative stress markers were higher than the peripheral levels in these colorectal cancer patients. Higher levels of these oxidative stress markers are associated with an advanced state of cancer.

Serum procarboxypeptidase A and carboxypeptidase A levels in pancreatic disease.

BACKGROUND AND OBJECTIVES: To determine the serum levels of procarboxypeptidase A (pro-CPA) and carboxypeptidase A (CPA) in patients with acute and chronic pancreatitis and pancreatic cancer. MATERIALS AND METHODS: Serum samples obtained from 96 patients with acute pancreatitis, 101 patients with chronic pancreatitis, 98 patients with pancreatic cancer and 96 control groups were assayed for biochemical parameters and serum pro-CPA and CPA. RESULTS: Serum pro-CPA and CPA levels were significantly higher in acute and in chronic pancreatic cancer patients compared to control group (p < 0.001). Pancreatic cancer patients had significantly higher serum pro-CPA and CPA levels when compared with acute and chronic pancreatitis cases (p < 0.001). CONCLUSION: These data prove for increased pro-CPA and CPA levels as a biomarker for the diagnosis of pancreatitis and pancreatic cancer.

Levels of matrix metalloproteinase-1 and tissue inhibitors of metalloproteinase-1 in gastric cancer.

AIM: To evaluate the levels of preoperative serum matrix metalloproteinase-1 (MMP-1) and tissue inhibitor of metalloproteinase-1 (TIMP-1) in gastric cancer. METHODS: One hundred gastric cancer patients who underwent gastrectomy were enrolled in this study. The serum concentrations of MMP-1 and TIMP-1 in these patients and in fifty healthy controls were determined using an enzyme-linked immunosorbent assay. RESULTS: Higher serum MMP-1 and TIMP-1 levels were observed in patients than in controls (P < 0.001). Serum MMP-1 and TIMP-1 levels were positively associated with morphological appearance, tumor size, depth of wall invasion, lymph node metastasis, liver metastasis, perineural invasion, and pathological stage. They were not significantly associated with age, gender, tumor location, or histological type. CONCLUSION: Increased MMP-1 and TIMP-1 were associated with gastric cancer. Although these markers are not good markers for diagnosis, these markers show in advanced gastric cancer.

Relationship between lymphocytes, IL2 and the hormones E2, LH, PRG and FSH in menopausal and postmenopausal women.

PROBLEM In this baseline study, our aim is to show the relationship of parameters and gonad hormones in menopausal and postmenopausal women. METHOD Blood samples were taken from menopausal and postmenopausal women (12-14 months and ≥10 years, respectfully, since their last menstruation). Adolescents aged 13.7 ± 0.7 were used as controls. Hormones were measured by ELISA and percentages of CD45, CD4, CD8, CD3, CD19, IL-2, CD25 and HLA-DR were measured by flow cytometry. RESULTS Both groups showed an increase in the percentage of CD3, CD4 and CD8. Levels of CD19 were significantly lower in the postmenopausal group. However, changes in immunologic parameters during menopause were less marked than the hormonal changes observed in these groups. Most of the correlations LH × CD3 (-ve), LH × IL2R (-ve) and E2 × CD19 (+ve) suggesting how menopausal women with particularly high LH or low E2 levels may be affected. Only CD3 and HLA-DR correlated with the hormonal changes in the postmenopausal group. IL-2 levels were high in the menopausal group and low in the postmenopausal group; however, no correlation was observed. DISCUSSION Menopause is characterized by increased levels of IL-2, which has critical immune-modulatory effects. These changes may be related to the overall hormonal change process observed during menopause.

Serum YKL-40 Levels in Patients with Gastric Cancer.

AIMS AND BACKGROUND: YKL-40 is secreted by several types of tumors. Increased serum YKL-40 levels have been reported in prostate, glioblastoma, breast and colorectal cancers. Determination of YKL-40 levels may serve as a valuable biomarker for the diagnosis and treatment of gastric cancer. The purpose of this study was to determine the serum YKL-40 levels expressed in gastric carcinomas. METHODS: Between 2009 and 2011, we retrospectively reviewed 100 patients with gastric cancer and compared their serum samples to 75 healthy volunteers. YKL-40 levels were determined by an enzyme-linked immunosorbent assay (ELISA). RESULTS: We found significantly higher serum levels of YKL-40 in patients with gastric cancer compared to the healthy population (P < 0.0001). We also found significant differences in serum YKL-40 levels between female and male patients with gastric cancer (P < 0.01). CONCLUSIONS: YKL-40 is over-expressed in gastric cancer, suggesting a more aggressive phenotype. YKL-40 may be a useful serum biomarker for gastric cancer identification, and future studies should focus on the role of YKL-40 in the tumorigenesis of gastric cancer and responsiveness toward treatment.