Hyung Ook Kim

Preoperative colonoscopy for patients with gastric adenocarcinoma

Background and Aim:  In patients with gastric adenocarcinoma (GA), the most common double primary cancer is colorectal cancer. The aim of the present study was to evaluate the necessity of preoperative colonoscopy in patients with GA who have no symptoms of colorectal disease or any past/family history of colorectal cancer.

Prognostic factors associated with long-term survival and recurrence in pancreatic adenocarcinoma.

BACKGROUND/AIMS It is very important to determine the prognostic factors for pancreatic adenocarcinoma when choosing surgical and conservative management strategies. In this study, we identified prognostic factors for survival and recurrence in patients with histologically proven pancreatic adenocarcinoma. METHODOLOGY Between January 2003 and December 2009, 82 patients with histologically proven pancreatic adenocarcinoma were considered for this study. Follow-up consisted of personal contact with patients or review of electronic medical records at this center and was terminated on December 31, 2011 or upon the patients death. RESULTS Overall survival rates of all patients at 1, 3, and 5 years were 51.9, 21.6 and 16.0%. Preoperative jaundice was the only independent prognostic factor for total pancreatic cancer patients, while N stage and perineural invasion in pathological findings was identified as an independent prognostic factor for survival of patients with surgical resection. Chemotherapy was the only independent prognostic factor for survival of patients who underwent palliative surgical bypass. CONCLUSIONS Preoperative jaundice in any patients, lymph node metastasis, perineural invasion in patients with surgical resection, and chemotherapy in patients undergoing palliative surgical bypass are important prognostic factors for survival of pancreatic cancer.

Laparoscopic appendectomy performed during pregnancy by gynecological laparoscopists

OBJECTIVE To evaluate the safety, feasibility, and pregnancy outcomes of laparoscopic appendectomy (LA) during pregnancy. STUDY DESIGN A retrospective review of eight pregnant women who underwent LA from January 2007 to December 2008. RESULTS The median age of the patients and median parity were 29.5 years (range, 25-34 years) and 0 (range, 0-1), respectively. The median operating time of LA was 22.5 min (range, 15-40 min). The median length of hospital stay was 3 days (range, 2-4 days). There was no maternal or fetal mortality or morbidity, conversion to laparotomy, or uterine injury. Seven women delivered seven healthy infants. One patient chose to have an elective abortion in another hospital. The histopathological diagnoses of the resected appendices were of acute appendicitis. CONCLUSION LA performed by gynecologic laparoscopists in pregnant women is safe, feasible, and effective.

Impact of chronologic age in the elderly with gastric cancer

Purpose Although the incidence of gastric cancer has declined in the general population, it is the second most frequent cause of death due to malignancy in the world with its incidence in the elderly increasing as a result of increased life expectancy. This present study tried to find the optimal treatment for patients aged 75 years or older with gastric cancer through comparison of the clinicopathological characteristics, surgical outcomes, and identifying prognostic factors of survival. Methods Elderly patients who underwent gastric resection for gastric cancer from January, 1999 to February, 2009 (n = 470) were divided into two groups: very elderly patients, 75 years or older (n = 95), and younger elderly patients, between 65 and 74 years old (n = 365). Results Distinct characteristics of very elderly patients included more frequent underlying disease, deeper invasion, and more frequent lymph node metastasis. There were significant differences in overall survival between the two groups at stages III-B and IV. However, postoperative hospital stays, postoperative morbidity, mortality and early stage did not differ between curatively resected patients in the two groups. Conclusion Due to improved postoperative care, gastrectomy of gastric cancer is the treatment of choice in very elderly patients. Therefore, early diagnosis through regular medical screening and curative gastrectomy with lymph node dissection should be performed in very elderly gastric cancer patients.

Field Cancerization in Sporadic Colon Cancer

Background/Aims Aberrant DNA methylation has a specific role in field cancerization. Certain molecular markers, including secreted frizzled-related protein 2 (SFRP2), tissue factor pathway inhibitor 2 (TFPI2), N-Myc downstream-regulated gene 4 (NDRG4) and bone morphogenic protein 3 (BMP3), have previously been shown to be hypermethylated in colorectal cancer (CRC). We aim to examine field cancerization in CRC based on the presence of aberrant DNA methylation in normal-appearing tissue from CRC patients. Methods We investigated promoter methylation in 34 CRC patients and five individuals with normal colonoscopy results. CRC patients were divided into three tissue groups: tumor tissue, adjacent and nonadjacent normal-appearing tissue. The methylation status (positive: methylation level >20%) of SFRP2, TFPI2, NDRG4, and BMP3 promoters was investigated using methylation-specific PCR. Results The methylation frequencies of the SFRP2, TFPI2, NDRG4 and BMP3 promoters in tumor/adjacent/nonadjacent normal-appearing tissue were 79.4%/63.0%/70.4%, 82.4%/53.6%/60.7%, 76.5%/61.5%/69.2%, 41.2%/35.7%/50.0%, respectively. The methylation levels of the SFRP,TFPI2, NDRG4 and BMP3 promoters in tumor tissues were significantly higher than those in normal-appearing tissue (SFRP2, p=0.013; TFPI2, p<0.001; NDRG4, p=0.003; BMP3, p=0.001). No significant correlation was observed between the methylation levels of the promoters and the clinicopathological variables. Conclusions The field effect is present in CRC and affects both the adjacent and nonadjacent normal-appearing mucosa.

Prognostic significance of quantitative carcinoembryonic antigen and cytokeratin 20 mRNA detection in peritoneal washes of gastric cancer patients.

BACKGROUND/AIMS Peritoneal carcinomatosis is the most common recurrence type in gastric cancer. Disseminated tumor cells derived from serosal invasion may be indicators of early peritoneal seeding and subsequent peritoneal dissemination. Reverse-transcriptase polymerase chain reaction (RT-PCR) techniques have been introduced to aid in detection of disseminated tumor cells in peritoneal washes, however, use of a single molecular marker lacks adequate sensitivity. We sought to improve both sensitivity and specificity in detecting disseminated tumor cells in peritoneal washes by using two markers; carcinoembryonic antigen (CEA) and cytokeratin 20 mRNA (CK20 mRNA). METHODOLOGY Between July 2007 and June 2010, peritoneal washing samples were collected from 131 patients who underwent surgery for histologically proven gastric cancer. CEA and CK20 mRNA levels were quantified using a Light Cycler. RESULTS Analysis using of the two markers had higher sensitivity (93.9%) and specificity (87.7%) than single marker detection (p<0.01, p<0.001 respectively). These analyses also correlated with various clinicopathological factors, and aided in predicting survival and peritoneal recurrence. CONCLUSIONS Two-marker analysis has a significant correlation of survival or peritoneal recurrence in gastric cancer, and this analysis may be more useful as a prognostic predictor of peritoneal recurrence compared with RT-PCR mediated detection of CEA or CK20 alone.

Age Over 80 is a Possible Risk Factor for Postoperative Morbidity After a Laparoscopic Resection of Colorectal Cancer.

Purpose With extended life expectancy, the mean age of patients at the time of diagnosis of colorectal cancer and its treatment, including radical resection, is increasing gradually. We aimed to evaluate the impact of age on postoperative clinical outcomes after a laparoscopic resection of colorectal cancers. Methods This is a retrospective review of prospectively collected data. Patients with primary colorectal malignancies or premalignant lesions who underwent laparoscopic colectomies between January 2009 and April 2013 were identified. Patients were divided into 6 groups by age using 70, 75, and 80 years as cutoffs: younger than 70, 70 or older, younger than 75, 75 or older, younger than 80, and 80 or older. Demographics, pathological parameters, and postoperative clinical outcomes, including postoperative morbidity, were compared between the younger and the older age groups. Results All 578 patients underwent a laparoscopic colorectal resection. The overall postoperative complication rate was 21.1% (n = 122). There were 4 cases of operative mortality (0.7%). Postoperative complication rates were consistently higher in the older groups at all three cutoffs; however, only the comparison with a cutoff at 80 years showed a statistically significant difference between the younger and the older groups. Conclusion Age over 80 is a possible risk factor for postoperative morbidity after a laparoscopic resection of colorectal cancer.

Early oral feeding following laparoscopic colorectal cancer surgery

Early oral feeding (EOF) following colorectal surgery can accelerate patient recovery and shorten hospital stay. However, some patients are intolerable to postoperative early oral feeding. The aim of this study was to evaluate the tolerability of EOF following laparoscopic colorectal cancer surgery and the effects of intravenous lidocaine.

Clinicopathologic Significance of BRAF Mutation and Extracellular Signal Regulated Kinase 1/2 Expression in Patients With a Colorectal Adenocarcinoma

Purpose BRAF mutation and expression of extracellular signal regulated kinase (ERK) are linked with colorectal carcinogenesis through the serrated pathway. BRAF and ERK1/2 play important roles in the activation of mitogen-activated protein (MAP) kinase signaling pathways. The present study investigated the clinicopathologic outcomes of BRAF mutation and ERK1/2 expression in patients with colorectal cancer (CRC) and the possibility of using them as prognostic indicators. Methods Dual-priming oligonucleotide-based multiplex polymerase chain reaction for BRAFV600E mutation and immunohistochemical analysis of ERK1/2 were performed using 65 formalin-fixed, paraffin-embedded samples from patients with CRC. We analyzed the dependences of the clinicopathologic features on BRAF mutation and ERK1/2 expression. Results Out of 65 samples from CRC patients, BRAF mutation was detected in 3 (4.6%). The 3 patients with BRAF mutation presented with T3 CRC with lymph node metastasis (stage III) showing moderately or poorly differentiated histology. ERK1 and ERK2 were positively detected in 73.8% and 15.4% of the patients with CRC, respectively. ERK1 expression was significantly correlated with lymph node metastasis (P = 0.049). ERK2 expression was significantly correlated with tumor emboli (P < 0.05), tumor invasion (P = 0.035), lymph node metastasis (P = 0.017), and stage (P = 0.02). Conclusion BRAF mutation and ERK1/2 expression may be associated with advanced or more aggressive CRC. These molecular markers might play prognostic roles in CRC developed through the serrated pathway.

Is methylation analysis of SFRP2, TFPI2, NDRG4, and BMP3 promoters suitable for colorectal cancer screening in the Korean population?

Background/Aims Colorectal cancer (CRC) screening using stool DNA was recently found to yield good detection rates. A multi-target stool DNA test (Cologuard®, Exact Sciences), including methylated genes has been recently approved by the U.S. Food and Drug Administration. The aim of this study was to validate these aberrantly methylated genes as stool-based DNA markers for detecting CRC and colorectal advanced adenoma (AA) in the Korean population. Methods A single-center study was conducted in 36 patients with AA; 35 patients with CRC; and 40 endoscopically diagnosed healthy controls using CRC screening colonoscopy. The methylation status of the SFRP2, TFPI2, NDRG4, and BMP3 promoters was investigated blindly using bisulfate-modified stool DNA obtained from 111 participants. Methylation status was investigated by methylation-specific polymerase chain reaction. Results Methylated SFRP2, TFPI2, NDRG4, and BMP3 promoters were detected in 60.0%, 31.4%, 68.8%, and 40.0% of CRC samples and in 27.8%, 27.8%, 27.8%, and 33.3% of AA samples, respectively. The sensitivities obtained using 4 markers to detect CRC and AA were 94.3% and 72.2%, respectively. The specificity was 55.0%. Conclusions Our results demonstrate that the SFRP2, TFPI2, NDRG4, and BMP3 promoter methylation analysis of stool sample DNA showed high sensitivity but low specificity for detecting CRC and AA. Because of the low specificity, 4 methylated markers might not be sufficient for CRC screening in the Korean population. Further large-scale studies are required to validate the methylation of these markers in the Asian population and to find new markers for the Asian population.