In Kyu Lee

Multidimensional analysis of the learning curve for laparoscopic rectal cancer surgery.

BACKGROUNDnThe need for an initial learning experience in laparoscopic colorectal cancer surgery has been well established. However, the inherent differences in the complexity and results of laparoscopic rectal cancer surgery, as compared to colon surgery, warrant a study to analyze the learning curve exclusively for rectal cancer resections.nnnMATERIALS AND METHODSnfour hundred thirty-one patients operated on between April 1994 and March 2006 were analyzed retrospectively for changes in surgical outcomes according to case sequence. A multidimensional analysis was done, based on the following parameters: conversion to laparotomy, intraoperative complications, postoperative complications, reoperations, operative time, and transfusion volumes. Multiple statistical methods were used for evaluation of the learning curve, which included the cumulative sum (CUSUM) method, risk-adjusted CUSUM, moving average method, and analysis of variance (ANOVA).nnnRESULTSnThe risk factors for conversion were prior abdominal surgery (hazard ratio, 2.52; 95% CI, 1.04-6.10; P = 0.04) and tumor size > or =3.5 cm (hazard ratio, 5.05; 95% CI, 1.95-13.08; P = 0.001). Risk-adjusted CUSUM analysis showed that case 61 was the peak change point for conversion. Postoperative complications occurred in 56 patients (13.0%), and the rate was associated significantly with case sequence (P < 0.001). The turning point in the CUSUM model occurred at case 79, and the complication rates decreased thereafter. Operative time and intraoperative transfusion volumes stabilized over cases 61-75 and declined thereafter.nnnCONCLUSIONSnMultidimensional analysis considering various surgical outcomes is necessary to evaluate the learning curve for laparoscopic rectal cancer surgery. The effective surgical learning curve was approximately 60-80 procedures in this series.

The diagnostic criteria for right colonic diverticulitis: prospective evaluation of 100 patients

Background and aimsIn this study, we evaluate prospective diagnostic criteria and propose a clinical scoring system for the evaluation of patients suspected to have right colonic diverticulitis (RCD) prospectively.Patients and methodsOne hundred adult patients, who were clinically suspected to have appendicitis or RCD, and in whom we were not able to preoperatively rule out appendicitis, were examined prospectively. Patients were scored upon clinical presentation based on major diagnostic criteria included (1) no migration pain to the right lower quadrant; (2) a leukocyte count <10,000/mm3; (3) lateralized abdominal pain, and (4) a history of right colonic diverticulum (two points each). Minor diagnostic criteria (one point each) included (1) a history of right lower quadrant abdominal pain; (2) no symptoms of nausea or vomiting; (3) symptoms of constipation or diarrhea, and (4) abdominal pain for at least seven days. For patients in whom the diagnostic score exceeded two points, a contrast enhanced computed tomography (CT) scan of the abdomen was performed.ResultsThirteen patients had a final diagnosis of RCD. These diagnostic criteria demonstrated a sensitivity of 85%, a specificity of 68%, a positive predictive value of 28%, a negative predictive value of 97%, and a diagnostic accuracy of 70%. Among the 38 patients examined with CT, diagnoses for acute diverticulitis included nine true positives, 26 true negatives, two false positives, and one false negative.ConclusionPerforming CT scans after application of these diagnostic criteria gave a superior preoperative diagnostic rate for patients with RCD.

Simultaneous Laparoscopic Resection of Primary Colorectal Cancer and Metastatic Liver Tumor: Initial Experience of Single Institute

BACKGROUNDnApproximately 20%-25% of patients with colorectal cancer have synchronous liver metastasis at the time of diagnosis. Simultaneous resection of primary colorectal cancer and metastatic liver tumor is the treatment option in colorectal cancer with liver metastasis. The aim of this study was to report our initial experiences of simultaneous laparoscopic resection of colorectal cancer and liver metastasis.nnnMETHODSnA single-center, retrospective study of 10 cases of laparoscopic simultaneous resection of colorectal cancer and liver metastasis was carried out.nnnRESULTSnThe patients average age was 63.7 years (range, 48-75 years) and average body mass index was 23.5 kg/m2(range, 20-27.4 kg/m2). The primary cancer was right-sided colon cancer in 4 cases, left-sided colon cancer in 3 cases, and rectal cancer in 3 cases. Single-lesion liver metastasis was found in 6 cases and two or more lesion liver metastasis was found in 4 cases. The mean operating time was 401 minutes (range, 230-620 minutes) and blood loss was 500 mL (range, 60-1000 mL). The mean hospital stay was 10 days (range, 7-15 days). One case was converted to open surgery and anastomotic leakage was encountered in the converted case.nnnCONCLUSIONSnThis study shows that simultaneous laparoscopic resection of primary colorectal cancer and liver metastasis is safe and technically feasible in selected patients.

Prognostic Value of CEA and CA 19-9 Tumor Markers Combined with Cytology from Peritoneal Fluid in Colorectal Cancer

BackgroundEarly diagnosis and management of peritoneal metastases from colorectal cancer patients are difficult clinical challenges. The aims of this study were to evaluate the clinical significance of tumor markers and cytology in peritoneal effusions (PE) and peritoneal irrigation fluid (PI) and to determine their value as prognostic indicators in this disease.MethodsTwo hundred thirty-four consecutive patients who underwent abdominal surgery for colorectal cancer from January 2006 to December 2007 were included, and tumor markers and cytology in PE and PI were analyzed prospectively.ResultsThe incidence of free cancer cells retrieved from peritoneal samples was 7.9%. Cytology was positive in 40.0% by Papanicolaou and Giemsa staining, 73.3% by hematoxylin and eosin staining of cell blocks, and 66.7% by carcinoembryonic antigen (CEA) and calretinin immunohistochemistry. Multivariate analysis revealed that peritoneal CEA and cancer antigen (CA) 19–9 in PI were correlated with peritoneal metastasis and cytology. Level of peritoneal fluid CEA was statistically significantly correlated with recurrence and peritoneal metastatic recurrence in patients with negative peritoneal cytology. Cytology, peritoneal CEA, and peritoneal CA 19-9 showed correlations with cancer-free survival and overall survival.ConclusionsThese correlations demonstrate the importance of continuous follow-up of peritoneal metastasis if there is positive cytology or an increase in CEA and CA 19-9 in peritoneal fluid.

The expression of multiple proteins as prognostic factors in colorectal cancer: cathepsin D, p53, COX-2, epidermal growth factor receptor, C-erbB-2, and Ki-67.

Background/Aims A single gene mutation alone cannot explain the poor prognosis of colorectal cancer. This study aimed to establish a correlation between the expression of six proteins and the prognosis of colorectal cancer patients. Methods Tissue samples were collected from 266 patients who underwent surgery for colorectal cancer at our institution from January 2006 to December 2007. The expression of six proteins were determined using immunohistochemical staining of specimens. Results Cathepsin D, p53, COX-2, epidermal growth factor receptor, c-erbB-2, and Ki-67 expression were detected in 38.7%, 60.9%, 37.6%, 35.7%, 30.1%, and 74.4% of the samples, respectively. The expression of cathepsin D was significantly correlated with reduced cancer-free survival (p=0.036) and colorectal cancer-specific survival (p=0.003), but the other expression levels were not. In a multivariate analysis, cathepsin D expression was found to be an independent prognostic factor for poorer colorectal cancer-specific survival (hazard ratio, 8.55; 95% confidence interval, 1.07 to 68.49). Furthermore, patients with tumors expressing four or more of the proteins had a significantly decreased cancer-free survival rate (p=0.006) and colorectal cancer-specific survival rate (p=0.002). Conclusions Patients with cathepsin D positivity had a poorer outcome than patients who were cathepsin D-negative. Thus, cathepsin D may provide an indicator for appropriate intensive follow-up and adjuvant chemotherapy.

Clinical Characteristics of Gastric Cancer Associated with Pregnancy

Background/Aims: This study was conducted to evaluate the clinical features and treatment outcome of gastric cancer associated with pregnancy. Methods: Clinicopathologic characteristics of 15 patients who were diagnosed as having gastric cancer during pregnancy or within 1 year after delivery (the P-related group) were compared with those of 53 age-matched pregnancy-unrelated gastric cancer patients (the control group). Results: Significant differences were found in tumor stage and surgical curability; the numbers of stage IV disease were 12 (80%) and 21 (40%; p = 0.006), and those of curative resection were 4 (27%) and 20 (62%; p = 0.02) in the P-related and the control group, respectively. Three-year survival rate was significantly lower in the P-related group (23.3%) than in the control group (52.8%; p = 0.007). In the P-related group, only 3 patients, including one patient diagnosed using endoscopy, survived without recurrences. In the multivariate analysis, pregnancy was not identified as an independent risk factor associated with poor outcome. Conclusion: Gastric cancer associated with pregnancy is discovered at its advanced stage and consequently shows a dismal prognosis. Considering that the patients who underwent curative resection have a favorable prognosis, primary efforts should be focused on early diagnosis.

Transumbilical single-port laparoscopic transabdominal preperitoneal repair of inguinal hernia: initial experience of single institute.

Background Conventional laparoscopic repair of inguinal hernias is generally performed by using 3 ports. In this study, the authors report their initial experiences of transumbilical single-port transabdominal preperitoneal (TAPP) repair of inguinal hernia using a unique “single port.” Methods Since November 2008, transumbilical single-port TAPP was performed in 24 patients with an inguinal hernia. A wound retractor and a surgical glove attached with 5 mm trocar and 2 pipes were inserted through a 1.5 cm-sized transumbilical incision. TAPP procedure was performed similarly compared with conventional laparoscopy. Results Transumbilical single-port TAPP repair of an inguinal hernia was successfully performed in 24 patients (19 male and 5 female; 17 with an indirect hernia and 7 with a recurrent hernia; mean age 54.2 y; mean body mass index 24.2 kg/m2). No major or minor intraoperative and postoperative complication was encountered and no conversion to conventional 3-port approach or open surgery was required. Mean operating time was 65.6 minutes and mean hospital stay was 2.1 postoperative days. Conclusions Transumbilical single-port TAPP repair of an inguinal hernia is technically feasible, provides nearly scarless surgery and can be performed safely and effectively in selected patients with an inguinal hernia.

Novel Methods of Lymph Node Evaluation for Predicting the Prognosis of Colorectal Cancer Patients with Inadequate Lymph Node Harvest

Purpose Lymph node metastasis is an important factor for predicting the prognosis of colorectal cancer patients. However, approximately 60% of patients do not receive adequate lymph node evaluation (less than 12 lymph nodes). In this study, we identified a more effective tool for predicting the prognosis of patients who received inadequate lymph node evaluation. Materials and Methods The number of metastatic lymph nodes, total number of lymph nodes examined, number of negative metastatic lymph nodes (NL), lymph node ratio (LR), and the number of apical lymph nodes (APL) were examined, and the prognostic impact of these parameters was examined in patients with colorectal cancer who underwent surgery from January 2004 to December 2011. In total, 806 people were analyzed retrospectively. Results In comparison of different lymph node analysis methods for rectal cancer patients who did not receive adequate lymph node dissection, the LR showed a significant difference in overall survival (OS) and the APL predicted a significant difference in disease-free survival (DFS). In the case of colon cancer patients who did not receive adequate lymph node dissection, LR predicted a significant difference in DFS and OS, and the APL predicted a significant difference in DFS. Conclusion If patients did not receive adequate lymph node evaluation, the LR and NL were useful parameters to complement N stage for predicting OS in colon cancer, whereas LR was complementary for rectal cancer. The APL could be used for prediction of DFS in all patients.

Adjuvant therapy with zoledronic acid (AZURE-BIG 01/04): The influence of menopausal status and age on treatment effects.

502 Background: This study aimed to establish a correlation between the expression of cathepsin D; p53; Cox-2; EGFR; C-erbB2; Ki-67 protein and the prognosis of colorectal cancer patients.nnnMETHODSnTissue samples were collected from 266 patients who underwent surgery for colorectal cancer from January 2006 to December 2007. The expression of the six proteins was determined using immunohistochemical staining of paraffin-embedded tissue specimens.nnnRESULTSnCathepsin D, p53, Cox-2, EGFR, C-erbB2, and Ki-67 expression was detected in 38.7%, 60.9%, 37.6%, 35.7%, 30.1%, and 74.4% of the samples, respectively. The expression of cathepsin D was significantly correlated with reduced cancer-free survival (p=0.036) and overall survival (p=0.003), whereas the expression of the other proteins could not be correlated. In a multivariate analysis, after adjusting for age, sex, and stage, cathepsin D expression was found to be an independent prognostic factor for a short overall survival(HR=8.55, 95% CI 1.07-68.49). Furthermore, patients with tumors expressing four or more of the proteins had a significantly decreased cancer-free survival rate (p=0.006) and overall survival rate (p=0.002), when compared with patients expressing fewer than four of the proteins Conclusions: In this study, the expression of CD was correlated with a poor prognosis in terms of the cancer-free survival and the overall survival rate. Importantly, the high hazard ratio (HR=8.55) associated with CD expression from the multivariate analysis, even after adjusting for the tumor stage, demonstrates its potential as an independent, single-gene prognostic factor. The expression of four or more of the examined proteins was significantly correlated with a poor prognosis, even after adjusting for the stage. Currently, the prognostic value of a single gene marker in CRCA is very controversial, but based on these results, we believe that the number of expressed genes/proteins may be helpful in identifying patients with both early-stage cancer and a potentially poor prognosis, which will help to determine if adjuvant chemotherapy is necessary.

Effect of Adjuvant Chemotherapy on Stage II Colon Cancer: Analysis of Korean National Data

Purpose Debates exist regarding the effectiveness of adjuvant chemotherapy for stage II colon cancer. This study aimed to investigate the current status of adjuvant chemotherapy and its impact on survival for Korean stage II colon cancer patients by analyzing the National Quality Assessment data. Materials and Methods A total of 7,880 patientswho underwent curative resection for stage II colon adenocarcinoma between January 2011 andDecember 2014 in Koreawere selected randomly as evaluation subjects for the quality assessment. The factors that influenced overall survival were identified. The high-risk group was defined as having at least one of the following: perforation/obstruction, lymph node harvest less than 12, lymphovascular/perineural invasion, positive resection margin, poor differentiation, or pathologic T4 stage. Results The median follow-up period was 38 months (range, 1 to 63 months). Chemotherapy was a favorable prognostic factor for either the high- (hazard ratio [HR], 0.76; 95% confidence interval [CI], 0.38 to 0.59; p < 0.001) or low-risk group (HR, 0.74; 95% CI, 0.61 to 0.89; p=0.002) in multivariate analysis. This was also the case in patients over 70 years of age. The hazard ratio was significantly increased as the number of involved risk factors was increased in patients who didn’t receive chemotherapy. Adding oxaliplatin showed no difference in survival (HR, 1.36; 95% CI, 0.91 to 2.03; p=0.132). Conclusion Adjuvant chemotherapy can be recommended for stage II colon cancer patients, but the addition of oxaliplatin to the regimen must be selective.