Solitary fibrous tumor of the lesser omentum mimicking stomach gastrointestinal stromal tumor.

Solitary fibrous tumor (SFT) is a mesenchymal tumor that rarely occurs in the abdomen. We report a very rare case of an abdominal SFT in the lesser omentum. A 39-year-old Korean man was referred to our center for management of a 9 cm incidental mass in the abdominal space found on a chest computed tomography (CT) during a routine medical examination. He had no symptoms, and there were no specific findings on physical examination. A contrast enhancement CT was performed, and an extraluminal gastrointestinal stromal tumor in the stomach or a pancreatic origin mass was suspected. Surgery was performed and an enclosed mass in the lesser omentum was observed, which was resected completely. The postoperative course was uneventful. Based on microscopy, the omental tumor was diagnosed as SFT.

Time-Dependent Effects of Prognostic Factors in Advanced Gastric Cancer Patients.

PURPOSE: This study aimed to identify time-dependent prognostic factors and demonstrate the time-dependent effects of important prognostic factors in patients with advanced gastric cancer (AGC). MATERIALS AND METHODS: We retrospectively evaluated 3,653 patients with AGC who underwent curative standard gastrectomy between 1991 and 2005 at the Korea Cancer Center Hospital. Multivariate survival analysis with Cox proportional hazards regression was used in the analysis. A non-proportionality test based on the Schoenfeld residuals (also known as partial residuals) was performed, and scaled Schoenfeld residuals were plotted over time for each covariate. RESULTS: The multivariate analysis revealed that sex, depth of invasion, metastatic lymph node (LN) ratio, tumor size, and chemotherapy were time-dependent covariates violating the proportional hazards assumption. The prognostic effects (i.e., log of hazard ratio [LHR]) of the time-dependent covariates changed over time during follow-up, and the effects generally diminished with low slope (e.g., depth of invasion and tumor size), with gentle slope (e.g., metastatic LN ratio), or with steep slope (e.g., chemotherapy). Meanwhile, the LHR functions of some covariates (e.g., sex) crossed the zero reference line from positive (i.e., bad prognosis) to negative (i.e., good prognosis). CONCLUSIONS: The time-dependent effects of the prognostic factors of AGC are clearly demonstrated in this study. We can suggest that time-dependent effects are not an uncommon phenomenon among prognostic factors of AGC.

Is Helicobacter Pylori associated with Her2/neu Overexpression in Gastric Cancer Patients who Underwent Curative Resection?

BACKGROUND/AIMS: Human epidermal growth factor receptor 2 (Her2/neu) is an important target for treatment of gastric cancer using trastuzumab and Helicobacter pylori is a well-known risk factor of gastric cancer. We investigated the association of Her2/neu overexpression with Helicobacter pylori and other clinicopathologic factors in gastric cancer patients who underwent curative resection. METHODOLOGY: Her2/neu immunohistochemistry was performed in gastric cancer patients who underwent curative gastrectomy or endoscopic submucosal dissection. Analysis about its associations with clinicopathologic features such as Lauren histologic types, differentiation, Helicobacter pylori infection, location, depth of invasion, lymph node metastasis, and AJCC tumor stage was performed retrospectively. RESULTS: The incidence of Her2/neu 3+, 2+, 1+ and 0 was 8.9%, 22.1%, 4.4% and 64.6% respectively. Intestinal type of gastric cancer showed higher incidence of Her2/neu 3+ than diffuse type. The score 2+ and 3+ was more common in Helicobacter pylori-positive patients than Helicobacter pylori-negative patients (p = 0.024). 7th American joint Cancer Committee Tumor stage, depth of tumor invasion and lymph node metastasis did not show correlation with the level of Her2/neu expression. CONCLUSIONS: Helicobacter pylori-positive gastric cancer showed more Her2/neu overexpression. Helicobacter pylori eradication may be necessary to avoid Her2/neu overexpression.

Hepatic resection for hepatic metastases from gastric adenocarcinoma.

PURPOSE: The effects of hepatic resection on patients with metastatic tumors from gastric adenocarcinomas are unclear. Therefore, we analyzed early clinical outcomes in patients who underwent surgical resection for hepatic metastases from gastric adenocarcinomas. MATERIALS AND METHODS: From January 2003 to December 2010, 1,508 patients with primary gastric cancers underwent curative gastric resections at the Korea Cancer Center Hospital. Of these patients, 12 with liver-only metastases underwent curative hepatic resection. Their clinical data were analyzed retrospectively. RESULTS: The median follow-up period was 12.5 months (range, 1~85 months); no operative mortalities or major complications were observed. Three patients underwent synchronous resections, and 9 underwent metachronous resections. In the latter group, the median interval between gastrectomy and hepatectomy for hepatic metastasis was 10.5 months (range, 5~47 months). The overall 1- and 5-year survival rates of these 12 patients were 65% and 39%, respectively, with a median overall survival of 31.0 months; 2 patients survived for >5 years. CONCLUSIONS: Hepatic resection can be a feasible procedure for treating hepatic metastases from gastric adenocarcinomas. Although this study was small and involved only selected cases, the outcomes of the hepatic resections were comparable and long-term (>5 years) survivors were identified. Surgical resection of the liver can be considered a feasible option in managing hepatic metastases from gastric adenocarcinomas.

Test execution variation in peritoneal lavage cytology could be related to poor diagnostic accuracy and stage migration in patients with gastric cancer.

PURPOSE: Peritoneal lavage cytology is part of the routine staging workup for patients with advanced gastric cancer. However, no quality assurance study has been conducted to show variations or biases in peritoneal lavage cytology results. The aim of this study was to demonstrate a test execution variation in peritoneal lavage cytology between investigating surgeons. MATERIALS AND METHODS: A prospective cohort study was designed for determination of the positive rate of peritoneal lavage cytology using a liquid-based preparation method in patients with potentially curable advanced gastric cancer (cT2~4/N0~2/M0). One hundred thirty patients were enrolled and underwent laparotomy, peritoneal lavage cytology, and standard gastrectomy, which were performed by 3 investigating surgeons. Data were analyzed using the chi-square test and a logistic regression model. RESULTS: The overall positive peritoneal cytology rate was 10.0%. Subgroup positive rates were 5.3% in pT1 cancer, 2.0% in pT2/3 cancer, 11.1% in pT4a cancer, and 71.4% in pT4b cancer. In univariate analysis, positive peritoneal cytology showed significant correlation with pT stage, lymphatic invasion, vascular invasion, ascites, and the investigating surgeon. We found the positive rate to be 2.1% for surgeon A, 10.2% for surgeon B, and 20.6% for surgeon C (P=0.024). Multivariate analysis identified pT stage, ascites, and the investigating surgeon to be significant risk factors for positive peritoneal cytology. CONCLUSIONS: The peritoneal lavage cytology results were significantly affected by the investigating surgeon, providing strong evidence of test execution variation that could be related to poor diagnostic accuracy and stage migration in patients with advanced gastric cancer.

Risk stratification for serosal invasion using preoperative predictors in patients with advanced gastric cancer.

PURPOSE: Although serosal invasion is a critical predisposing factor for peritoneal dissemination in advanced gastric cancer, the accuracy of preoperative assessment using routine imaging studies is unsatisfactory. This study was conducted to identify high-risk group for serosal invasion using preoperative factors in patients with advanced gastric cancer. MATERIALS AND METHODS: We retrospectively analyzed clinicopathological features of 3,529 advanced gastric cancer patients with Borrmann type I/II/III who underwent gastrectomy at Korea Cancer Center Hospital between 1991 and 2005. We stratified patients into low- (≤40%), intermediate- (40~70%), and high-risk (>70%) groups, according to the probability of serosal invasion. RESULTS: Borrmann type, size, longitudinal and circumferential location, and histology of tumors were independent risk factors for serosal invasion. Most tumors of whole stomach location or encircling type had serosal invasion, so they belonged to high-risk group. Patients were subdivided into 12 subgroups in combination of Borrmann type, size, and histology. A subgroup with Borrmann type II, large size (≥7 cm), and undifferentiated histology and 2 subgroups with Borrmann type III, large size, and regardless of histology belonged to high-risk group and corresponded to 25% of eligible patients. CONCLUSIONS: This study have documented high-risk group for serosal invasion using preoperative predictors. And risk stratification for serosal invasion through the combination with imaging studies may collaboratively improve the accuracy of preoperative assessment, reduce the number of eligible patients for further staging laparoscopy, and optimize therapeutic strategy for each individual patient prior to surgery.

Comparative analysis of the efficacy and safety of chemotherapy with oxaliplatin plus fluorouracil/leucovorin between elderly patients over 65 years and younger patients with advanced gastric cancer.

BACKGROUND: A chemotherapy regimen with oxaliplatin, fluorouracil, and leucovorin is commonly used to treat advanced gastric cancer (AGC). This study was designed to compare the efficacy and the safety of oxaliplatin plus fluorouracil/leucovorin administered biweekly (mFOLFOX6) between elderly patients aged over 65 years and younger counterparts with AGC. METHODS: This analysis included 82 AGC patients (≥65:31, <65:51). Patients with previously untreated chemo-naïve advanced adenocarcinoma of the stomach received oxaliplatin 85 mg/m(2), 5-FU bolus 400 mg/m(2) on day 1 and 5-FU 1,500 mg/m(2), leucovorin 75 mg/m(2) 22 h infusion on days 1 and 2 every 2 weeks. The aim of the study was to compare efficacy and safety, including response rate (RR), progression-free survival (PFS), overall survival, and grade ≥3 adverse events, between patients aged ≥65 years and patients aged <65 years. RESULTS: Median progression-free survival (PFS) was not significantly different between both groups (≥65: 5.8 months, <65: 5.7 months, respectively, HR 0.77, 95% CI: 0.44-1.16, P = 0.18). Median overall survival was not significantly different between both groups (≥65: 10.3 months, <65: 9.5 months HR 0.83, 95% CI: 0.50-1.37, P = 0.46). The rate of grade 3 or 4 neutropenia did not differ with age group (≥65: 51.6%, <65: 43.1%); nor did the rates of neutropenic fever (≥65: 16.1%, <65: 5.9%), and infection without neutropenia (≥65: 3.2%, <65: 3.9%). Rates of grade ≥3 toxicities such as thrombocytopenia, nausea/vomiting, or peripheral neuropathy were not significantly different between the two groups. CONCLUSIONS: mFOLFOX6 maintains its efficacy and safety in elderly patients aged over 65 years in comparison with AGC patients aged <65 years. Its judicious use should be considered regardless of age.

Prognosis of curatively resected pT4b gastric cancer with respect to invaded organ type.

PURPOSE: Curative resection, including gastrectomy, extensive lymph node dissection, and combined resection of invaded organs, is the mainstay of treatment for T4b gastric cancers. We sought to investigate the clinicopathologic features, surgical outcomes, and prognostic factors of curatively resected pathologic T4b gastric cancer with a focus on organs invaded. METHODS: Data of 243 pT4b gastric cancer patients who underwent curative resection at Korea Cancer Center Hospital from 1991 to 2005 were retrospectively subjected to univariate and multivariate analyses. RESULTS: Overall 5-year survival rate and median survival time were 36.8% and 26 months, respectively. Five-year survival rates were 23.3% in the pancreatic invasion group (n = 67) and 42.1% in the nonpancreatic invasion group (n = 176) (P = 0.002). Regarding operative methods used for pancreatectomy in pancreatic invasion group, 5-year survival rates were 0% in the pancreaticoduodenectomy group (n = 9) and 27.4% in the other pancreatectomies group (n = 58) (P = 0.013). Multivariate analysis revealed that advanced lymph node stages (hazard ratio [HR] 1.637 for N0 vs. N1, HR 2.177 for N0 vs. N2, HR 3.241 for N0 vs. N3a, and HR 4.000 for N0 vs. N3b), encircling type of tumor (HR 1.804), and pancreatic invasion (HR 1.463) were independently unfavorable prognostic factors. CONCLUSIONS: In pT4b gastric cancer, pancreatic invasion was found to portend the least favorable prognosis, especially in cases requiring pancreaticoduodenectomy. However, prognoses were more favorable after curative resection in patients without advanced lymph node stages (N2, N3a, and N3b), an encircling type of gastric tumor, or pancreatic invasion. We propose a novel therapeutic strategy for patients with T4b gastric cancer.

Phenotypic Differences of Gastric Cancer according to the Helicobacter pylori Infection in Korean Patients.

PURPOSE: Infection with Helicobacter pylori is an important risk factor for gastric cancer in humans. We compared the clinicopathologic features of gastric cancer patients based on H. pylori infection. MATERIALS AND METHODS: We prospectively studied 155 patients who had gastric cancer and underwent gastrectomies in 1 hospital in Korea. We examined H. pylori infections using the rapid urease test (RUT) with gastrectomy specimens and collected clinical and pathologic data. RESULTS: The number of H. pylori infections based on the RUT was 137 (88%). The H. pylori-negative group was significantly associated with AGC and tumor histology. H. pylori infection was significantly correlated with type I/IIa in EGC and type III/IV/V in AGC. AGC was significantly correlated with larger tumor size, lymphatic invasion, perineural invasion, and H. pylori infection based on univariate and multivariate analyses. CONCLUSIONS: We report the prevalence of H. pylori based on the RUT in gastric cancer patients. H. pylori infection influences the tumor histology, progression, and growth type of gastric cancer.

High prevalence of osteoporosis in patients with gastric adenocarcinoma following gastrectomy.

AIM: To evaluate the prevalence and predictive factors of osteoporosis in patients with gastric adenocarcinoma after gastrectomy. METHODS: The study included 133 patients diagnosed with gastric adenocarcinoma but who did not undergo prior diagnostic work-up for osteoporosis. Bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry (DXA) and vertebral deformity was assessed by plain X-rays. We evaluated the effects of age, sex, body mass index (BMI), anemia, back pain, vertebral deformity, tumor staging, reconstruction type, and past medical history to determine predictive factors of osteoporosis in these patients. RESULTS: The prevalence of osteoporosis in the lumbar spine was 38.3% (male, 28.9%; female, 54.0%), and 15.0% in the femoral neck (male, 10.8%; female, 22.0%). The vertebral deformity rate was 46.6% (male, 43.4%; female, 52.0%). Age, BMI and hemoglobin correlated with BMD (P < 0.01). In males, anemia and age > 64 years were independent predictive factors of osteoporosis in multivariate analysis. In females, back pain was an independent factor for osteoporosis. CONCLUSION: The results of this study revealed that prevalence of osteoporosis and vertebral bone deformity rate were high in gastric cancer patients, regardless of post-gastrectomy duration and operation type. Early diagnosis and a proper management plan must be established in these patients.