The safety of the dissection of lymph node stations 5 and 6 in pylorus-preserving gastrectomy

BACKGROUND

This study was intended to examine the safety of possibly incomplete dissection of lymph node stations (LNS) 5 and 6 in pylorus-preserving gastrectomy (PPG) for gastric cancer.

MATERIALS AND METHODS

We reviewed the medical information from 1802 gastric cancer patients who underwent curative gastrectomy and whose lymph nodes were topographically classified according to LNS between March 2003 and December 2008. We divided the patients who underwent subtotal gastrectomy into 2 groups according to the distance between the distal resection margin (DRM) and primary tumor: those with a distance of < 6 cm (the < 6 DRM group) and those with a distance of >or= 6 cm (the >or= 6 DRM group). We analyzed the lymph node metastasis rate to LNS 5 and 6 according to T stage and the location. The number of retrieved lymph nodes according to LNS was compared between subtotal gastrectomy (STG) and PPG.

RESULTS

The metastasis rate to LNS 5 was very rare in >or= 6 DRM group: T1a, 0% (0 of 105); T1b, 0.9% (1 of 113); and T2a, 0% (0 of 56), although the number of retrieved LNS 5 was significantly lower in PPG than in STG. The metastasis rate to LNS 6 in the >or= 6 DRM group was significantly lower than in the < 6 DRM group, but higher than that of LNS 5: T1a, 0% (0 of 107); T1b, 1.8% (2 of 114); and T2a, 3.6% (2 of 56). The number of retrieved LNS 6 was not significantly different between STG and PPG.

CONCLUSIONS

PPG seems to be safe for early gastric cancer located >or= 5 cm from the pylorus in terms of LNS 5 and 6.

Comparison of the long-term outcomes of uncinate process cancer and non-uncinate process pancreas head cancer: poor prognosis accompanied by early locoregional recurrence

PURPOSE

The embryologic and anatomic peculiarity of the uncinate process may result in distinct clinical features, but few studies have addressed the uncinate process cancer. The purpose of this study was to compare the clinicopathologic characteristics and identify the prognostic factors that affect the survival and recurrence of pancreatic head cancer by tumor location.

METHODS

Between January 2002 and December 2008, 453 patients (161 with uncinate and 292 with non-uncinate process cancer) were treated for pancreatic head cancer. Clinicopathologic variables were analyzed by tumor location.

RESULTS

Invasion into the superior mesenteric artery (SMA) occurred more frequently (p < 0.001), and overall resectability (p = 0.003), curative resection (p < 0.001), and R0 resection rates (22.3% vs 35.6%; p = 0.003) were lower for uncinate process cancer. Furthermore, overall survival after R0 resection was lower for uncinate process cancer (median 21 vs 26 months; p = 0.018), and this was accompanied by more frequent (p = 0.038) and earlier (median 13 vs 52 months; p < 0.001) locoregional recurrence. Concurrent chemoradiation increased overall (median, 26 vs 13 months; p < 0.001) and disease-free survival (median, 15 vs 6 months; p < 0.001) of uncinate and non-uncinate process cancer, respectively, after curative-intended resection.

CONCLUSION

In uncinate process cancer, frequent invasion into the SMA led to lower resectability. Furthermore, lower survival after R0 resection was accompanied with frequent and early locoregional recurrence. Strategies to improve surgical and perioperative locoregional control are required for uncinate process cancer.

Clinical efficacy of organ-preserving pancreatectomy for benign or low-grade malignant potential lesion

The clinical usefulness of organ-preserving pancreatectomy is not well established due to technical difficulty and ambiguity of functional merit. The purpose of this study is to evaluate the clinical efficacy of organ-preserving pancreatectomy such as duodenum-preserving resection of the head of the pancreas (DPRHP), pancreatic head resection with segmental duodenectomy (PHRSD), central pancreatectomy (CP) and spleen-preserving distal pancreatectomy (SPDP). Between 1995 and 2007, the DPRHP were performed in 14 patients, the PHRSD in 16 patients, the CP in 13 patients, and the SPDP in 45 patients for preoperatively diagnosed benign lesions or tumors with low-grade malignant potential. The clinical outcomes including surgical details, postoperative complications and long-term functional outcomes were compared between organ-preserving pancreatectomy and conventional pancreatectomy group. Major postoperative complications constituted the following: bile duct stricture (7.1% [1/14]) in DPRHP, delayed gastric emptying (31.2% [5/16]) in PHRSD, pancreatic fistula (21.4% [3/14]) in CP. There were no significant differences in postoperative complications and long-term functional outcomes between two groups. Organ-preserving pancreatectomy is associated with tolerable postoperative complications, and good long-term outcome comparing to conventional pancreatectomy. Organ-preserving pancreatectomy could be alternative treatment for benign or low-grade malignant potential lesion of the pancreas or ampullary/parapapillary duodenum.

Expansion of hepatic progenitor cell in fatty liver graft after living donor liver transplantation

Although it is known that steatotic livers have a reduced ability to regenerate, most individuals with steatosis show generally benign prognosis. We hypothesized that a proliferative blockade in steatotic hepatocytes results in the compensatory expansion of hepatic progenitor cells (HPC) during fatty liver regeneration. Fifty-four cases of living donor liver transplantation (LDLT) with a liver biopsy performed at the postoperative 10th day were examined. HPC were counted by immunofluorescence histochemical dual-staining technique using cytokeratin 7 and Ki-67, and the replicative arrest of hepatocytes was assessed by p21 immunohistochemistry. The degree of ductular proliferation during regeneration 10 days after LDLT correlated both with the degree of steatosis and the number of HPC (P < 0.001). There was no difference in the average number of HPC and the replicative arrest index between donors with or without steatosis before LDLT (P = 0.111 and P = 0.062). However, degree of steatosis correlated with both the expansion of HPC and the replicative arrest index during liver regeneration 10 days after LDLT (P < 0.001 and P < 0.001, respectively). Moreover, increased replicative arrest was strongly associated with HPC expansion (P < 0.001). In conclusion, the compensatory expansion of HPC as a result of impaired hepatocyte replication occurred during steatotic liver regeneration after LDLT.

Safety of extended endoscopic mucosal resection and endoscopic submucosal dissection following the Japanese Gastric Cancer Association treatment guidelines

BACKGROUND

Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are widely performed. Indications for these procedures have been extended in Korea and Japan. The aim was to evaluate whether these extended indications are safe.

METHODS

All patients who had surgery for early gastric cancer at Seoul National University Bundang Hospital between May 2003 and December 2007 were identified from a prospective database. Lymph node status was examined in patients who met extended indications for EMR and had undergone surgical resection.

RESULTS

Of patients with mucosal cancers, 129 met extended indications for EMR or ESD and three (2.3 per cent) had lymph node metastasis. Of the 52 submucosal cancers meeting extended indications for EMR or ESD, two (4 per cent) had lymph node metastasis. Differentiated mucosal cancers without ulcer formation did not have lymph node metastasis, irrespective of size.

CONCLUSION

Extending the indications for EMR and ESD according to the Japanese Gastric Cancer Association guidelines carries an increased risk of lymph node metastasis. For cancers meeting these criteria, treatment by gastric resection with lymph node dissection should still be considered. A well differentiated mucosal cancer of any size without ulceration may be considered as an extended indication for EMR or ESD.

Predictive factors associated with the reversibility of post-transplantation diabetes mellitus following liver transplantation

Post-transplantation diabetes mellitus (PTDM) is reversible in a considerable number of patients. We examined the prevalence and predictive factors of transient PTDM following liver transplantation. Forty-two of 74 PTDM patients showed the clinical features of transient PTDM. Compared with the persistent PTDM patients, they were characterized by younger age at the time of transplantation (49+/-7 vs. 53+/-8 yr, P<0.05), longer time before the development of PTDM (44+/-59 vs. 13+/-20 days, P<0.05), lower rate of hepatitis c virus seropositivity (0.0 vs. 9.4%, P<0.05), and use of mycophenolate mofetil (59.5 vs. 28.1%, P<0.05). Among these risk factors, age at the time of transplantation is the single independent predictive factor associated with the reversibility of PTDM.

Actual 3-year survival after laparoscopy-assisted gastrectomy for gastric cancer

OBJECTIVE

To analyze 3-year actual disease-free survival after laparoscopy-assisted gastrectomy for gastric cancer on the assumption that 3-year disease-free survival may represent 5-year overall survival.

DESIGN

Retrospective analysis.

SETTING

Department of surgery of a university hospital.

PATIENTS

A total of 197 patients who underwent laparoscopy-assisted gastrectomy for gastric cancer from May 1998 to September 2007 and who were followed up for more than 3 years.

MAIN OUTCOME MEASURES

Feasibility and long-term survival rate with survival analysis by the Kaplan-Meier method.

RESULTS

Subtotal and total gastrectomies were performed in 178 and 19 patients, respectively. The scope of the lymph node dissections were D1 + beta (n = 152) and D2 (n = 45). There were 153, 28, 8, 6, 1, and 1 patients in stages Ia, Ib, II, IIIa, IIIb, and IV, respectively. The median follow-up was 45 months (range, 1-113 months), and there were 7 recurrences. Multivariate analysis of disease-specific survival showed that depth of invasion and lymph node metastasis influenced the prognosis independently. The actual 3-year disease-free survival rate for all patients was 96.9%. The 173 patients with early gastric cancer and 24 with advanced gastric cancer showed 98.8% and 79.1% actual 3-year disease-free survival rates, respectively.

CONCLUSIONS

Laparoscopy-assisted gastrectomy is acceptable oncologically in early gastric cancer if 3-year disease-free survival represents 5-year overall survival. Laparoscopy-assisted gastrectomy may also play an important role in the treatment of advanced gastric cancer.

Improved outcome of adult recipients with a high model for end-stage liver disease score and a small-for-size graft

Although adult-to-adult living donor liver transplantation (ALDLT) has shown comparable outcomes to deceased donor liver transplantation, the outcome of patients with a high MELD score (>25) and a small-for-size graft (SFSG<0.8% of graft-to-recipient weight ratio) is not known. For 7 years, 167 consecutive hepatitis B virus-infected recipients underwent ALDLT at our institution. Based on their MELD score without additional score for hepatocellular carcinoma (HCC), the recipients were divided into Group L (low MELD score, n = 105) or Group H (high MELD score, n = 62). To analyze the risk of the graft size, the patients were further stratified as follows: Group Hs (high MELD score and SFSG, n = 11), Hn (high MELD score and normal size graft, n = 51), Ls (low MELD score and SFSG, n = 18), and Ln (low MELD score and normal size graft, n = 87). The primary endpoint was one-year patient survival rate (1-YSR). The mean follow-up period was 32.6 months. The mean MELD scores were 17.1 in Group L and 32.6 in Group H. Group H had more patients with the complications of cirrhosis but less patients with HCC than Group L (p < 0.05). However, major morbidity rates and 1-YSR were similar in comparisons between Group L (46.7% and 86.7%) and H (59.7% and 83.8%) (p > 0.05). 1-YSR was similar among Group Hs (72.7%), Hn (86.3%), Ls (83.3%), and Ln (88.5%) groups (p = 0.278). The multivariate analysis revealed accompanying HCC and the year of transplant were risk factors for poor 1-YSR. However, 1-YSR without HCC patients was also similar in comparisons between group L (90.2%) and H (91.7%) (p = 0.847), and among Group Hs (80.0%), Hn (94.7%), Ls (72.7%), and Ln (96.7%) (p = 0.072). In conclusion, high MELD score (>25) didn't predict 1-YSR in ALDLT. Improvement of the 1-YSR might be affected by center's experience as well as the selection of patients with low risk of recurrence of HCC.

Laparoscopic hepatectomy for a modified right graft in adult-to-adult living donor liver transplantation

BACKGROUND

We performed a modified right hepatectomy completely by laparoscopic techniques preserving the middle hepatic vein (MHV) branches in adult-to-adult living donor liver transplantation (LDLT).

PATIENTS AND METHODS

Two young women (24 and 25 years old) volunteered to be live donors for their parents who had hepatocellular carcinomas. As the donors expressed concerns about scarring, we performed a laparoscopic procedure using a hand port device. Mobilization of the right liver and the hepatic parenchymal transection were performed under pneumoperitoneum. Parenchymal transection was performed using a laparoscopic ultrasonic aspirator without the Pringle maneuver. During parenchymal transection, major MHV branches >5 mm were preserved using Hem-o-lock clips. The graft was extracted through the hand port site. On the back table, the 3 MHV branches were reconstructed using an artificial vascular graft. The livers were transplanted without complications.

RESULTS

The operative times for the donors were 765 and 898 minutes. The donors did not require transfusions or reoperation; they were discharged on postoperative days 10 and 14 with normal liver functions.

CONCLUSION

A hepatectomy performed completely by laparoscopic techniques for a right graft with preservation of the MHV branches was technically feasible.

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.

Diagnostic accuracy of T and N stages with endoscopy, stomach protocol CT, and endoscopic ultrasonography in early gastric cancer

BACKGROUND

Preoperative accurate diagnosis of the T and N stages in early gastric cancer (EGC) is important in determining the application of various limited treatments. The aim of this study is to analyze the accuracy of T and N staging of EGC with esophagogastroduodenoscopy (EGD), Stomach protocol CT (S-CT), and endoscopic ultrasonography (EUS), and the factors influencing the accuracy.

METHODS

Four hundred and thirty-four patients preoperatively diagnosed as EGC using EGD or S-CT and undergoing curative gastrectomy at Seoul National University Hospital in 2005 were included. The T and N stage reviewed by experienced personnel were compared with the surgical pathology.

RESULTS

The predictive values for EGC of EGD, S-CT, and EUS were 87.4%, 92.2%, and 94.1%, respectively. The predictive values for node negativity of S-CT, and EUS were 90.1% and 92.6%, respectively. The factors leading to underestimation of T stage with EGD were the upper third location, the size greater than 2 cm, and diffuse type of tumor. Those with S-CT were female sex, the upper third location and lesion size greater than 2 cm.

CONCLUSIONS

Before applying limited treatment for EGC, a surgeon should consider the risk factors of underestimation of T stage with EGD or S-CT.

Risk factors for operative complications in elderly patients during laparoscopy-assisted gastrectomy

BACKGROUND

We evaluated the feasibility of laparoscopy-assisted gastrectomy in elderly patients with gastric cancer.

STUDY DESIGN

We performed a retrospective analysis of 632 patients who underwent laparoscopy-assisted gastrectomy from May 2003 to December 2007 at Seoul National University Bundang Hospital. Postoperative complication rates were compared between patients older and younger than 70 years of age.

RESULTS

Of the 632 patients, 515 (81.5%) were younger than 70 years and 117 (18.5%) were aged 70 years or older. Significant differences in the prevalence of cardiovascular disease and hypertension were observed in patients older than 70 years (p < 0.05). Although the overall complication rates of the patients younger and older than 70 years were 12.6% and 17.9%, respectively, there was no statistically significant difference between groups (p=0.12). Multiple logistic regression analysis revealed that comorbidities with hypertension or with liver cirrhosis were the only variables that correlated independently with postoperative complications.

CONCLUSIONS

Complications after laparoscopy-assisted gastrectomy for patients older than 70 years of age with gastric cancer were similar to those of younger patients. But a careful approach is required when patients older than 70 years of age have hypertension or liver cirrhosis.

Clinical comparison of distal pancreatectomy with or without splenectomy

The spleen may be preserved during distal pancreatectomy (DP) for benign disease. The aim of this study was to compare the perioperative and postoperative courses of patients with conventional DP and spleen-preserving distal pancreatectomy (SPDP) for benign lesions or tumors with low-grade malignant potential occurred at the body or tail of the pancreas. A retrospective analysis was performed for the hospital records of all the patients undergoing DP and SPDP between January 1995 and April 2006. One-hundred forty-three patients underwent DP and 37 patients underwent SPDP. There were no significant differences in age, sex, indications of operation, estimated blood loss, operative time, and postoperative hospital stay between the two groups. Pancreatic fistula occurred in 21 (13.3%) patients following DP and in 3 (8.1%) following SPDP without a significant difference (p=0.081). Portal vein thrombosis occurred in 4 patients after DP. Splenic infarction occurred in one patient after SPDP. Overwhelming postosplenectomy infection was observed in one patient after DP. SPDP can be achieved with no increase in complication rate, operative time, or length of postoperative hospitalization as compared to conventional DP. Additionally, it has the advantage of reducing the risk of overwhelming postsplenectomy infection and postoperative venous thrombosis.

Actual long-term outcome of Klatskin's tumor after surgical resection

BACKGROUND/AIMS

To analyze the actual long-term outcome of Klatskin's tumor after surgical resection and to identify the factors affecting long-term survival.

METHODOLOGY

We reviewed the records of 145 Klatskin's tumor cases who underwent operation from 1991 to 1999 and analyzed the actual outcome and prognostic factors. We also compared the clinicopathologic characteristics of long-term and short-term survivors.

RESULTS

Seventy-six patients underwent resection (resection rate 52.4%). Twenty-one of the 76 patients survived more than 5 years, an actual 5-year survival rate of 28%, and of these survivors, 4 had recurrent disease at 5 years and 3 developed recurrence after 5 years. Five patients with well-known poor prognostic factors, such as, lymph node metastasis and resection margin involvement survived more than 5 years. Lymph node metastasis was identified as a significant prognostic factor, and long-term survivors were found to have more favorable T and N stages than short-term survivors.

CONCLUSIONS

The actual 5-year survival rate after resection was 28%, and lymph node metastasis was identified as a significant prognostic factor. Long-term follow-up is mandatory, because recurrence occurs beyond 5 years after surgery. An aggressive surgical approach should be used to give patients with poor prognostic factors a chance of survival.

Clinical outcome of pylorus-preserving gastrectomy in gastric cancer in comparison with conventional distal gastrectomy with Billroth I anastomosis

BACKGROUND

Pylorus-preserving gastrectomy (PPG) was originally a treatment option in gastric ulcer surgery and is now being performed as a limited surgery in some early gastric cancer cases. This study was designed to evaluate the postoperative functional characteristics of PPG versus conventional distal gastrectomy with Billroth I anastomosis (BI).

METHODS

Patients who underwent PPG (study group) between November 1999 and April 2003 were enrolled and BI patients (control group) were matched for number, gender, age, weight, height, stage, and follow-up period. We evaluated postprandial symptoms and nutritional status. Gastric emptying studies with a 99mTc gamma camera, follow-up endoscopies with random biopsies of remnant gastric mucosa to evaluate bile reflux gastritis, and ultrasonography to detect gallbladder stones were performed. Recurrence and survival also were investigated.

RESULTS

Twenty-two PPG patients (study group) and 17 BI patients (control group) were enrolled. Overall modified Visick scores of postprandial symptoms were lower in PPG patients than in BI patients (0.9 +/- 0.7 vs. 2.3 +/- 1.4; p = 0.018). Gastric emptying was delayed in PPG patients versus BI patients for solids (p < 0.05). Moderate gastritis, bile reflux, and gallbladder stone were observed only in BI patients. Remnant stomach pathologic findings corresponding to bile reflux gastritis in the two groups were similar, except for Helicobacter pylori colonization. No recurrence occurred in either group (mean follow-up period = 41 +/- 9.5 months).

CONCLUSIONS

PPG patients had fewer subjective postprandial symptoms than BI patients. The present study also suggests that PPG has advantages over BI in terms of the avoidance of bile reflux and gallbladder stones.

Synchronous and metachronous cancers in patients with gastric cancer

BACKGROUND AND OBJECTIVES

The purpose of this study is to investigate characteristics of synchronous and metachronous cancer in gastric cancer and to suggest appropriate methods of treatment management.

METHODS

We reviewed 4,593 patients who underwent operations for gastric cancer at Seoul National University Hospital from 1999 to 2005. We selected those patients who had also been diagnosed with another primary cancer and classified patients into three groups according to the date of detection of another primary cancer. We analyzed their clinicopathological features.

RESULTS

The incidence of synchronous or metachronous cancer in addition to gastric cancer was 3.4%. The most common another primary cancer was colorectal cancer (20.1%), followed by lung cancer and liver cancer. The majority of synchronous cancers were operated on at the same time as gastric cancer. Eighty-five percent of the synchronous group and 45% of the post-metachronous group were detected by a routine checkup, without prior symptoms. There was no postoperative mortality and the overall 5-year survival rate was 69.4%.

CONCLUSION

Synchronous cancer should be considered in the preoperative workup and combined resection should be applied whenever possible. Periodic examination for metachronous cancer is necessary during the postoperative period.

Clinicopathologic characteristics of gastrointestinal stromal tumor of the stomach

BACKGROUND/AIMS

This study was undertaken to investigate a surgical role in treating gastrointestinal stromal tumors (GISTs) of the stomach and to find their behavior and prognostic factors.

METHODOLOGY

The clinicopathologic results of 112 patients with gastric GISTs who underwent surgery from December 1999 to August 2006 were reviewed.

RESULTS

Forty (35.7%) patients had no symptoms. Of a total of 112 patients, curative resections were performed on 105 (93.8%). There were 41 (36.6%) high-risk patients. The mean follow-up period was 34.3 months (1-82 months) and there were two deaths. Six (5.7%) of the 105 patients who received curative resections had recurrences and all recurrences occurred only in high-risk patients. Univariate analysis showed that tumor size and mitotic count were prognostic for disease-free survival of GIST patients (p=0.0004 and p<0.0001, respectively), but multivariate analysis identified mitotic count as the only prognostic factor for disease-free survival of GIST patients (p=0.039).

CONCLUSIONS

The curative resection rate was high in GISTs of the stomach and they were treated using various surgical procedures. Patient survival after curative resection was good. Mitotic count was the independent prognostic factor for disease-free survival and only high-risk patients had recurrences.

Hypophosphatemia after live donor right hepatectomy

BACKGROUND

It is known that hypophosphatemia can frequently develop after hepatectomy and may result from an increased renal phosphate leak. However, its clinical significance has not been well defined in live donor right hepatectomy (LDRH). The purpose of this study was to investigate the correlation between postoperative hypophosphatemia and both donor morbidity and the degree of hepatic resection in LDRH.

METHODS

In all, 88 live liver donors were enrolled, who had undergone right hemihepatectomy between January 2002 and December 2005. Based on the severity of the postoperative hypophosphatemia, we divided the donors into 3 groups: mild (1.5-2.5 mg/dL, n = 30), moderate (1.0-1.5 mg/dL, n = 41), and severe (<1.0 mg/dL, n = 17), and we compared the incidence of complications among these groups. In addition, we investigated the possible correlation between the nadir phosphorus levels and both remnant liver volume and alkaline phosphate (ALP) levels.

RESULTS

All donors developed hypophosphatemia postoperatively. The mean value of the nadir phosphorus levels was 1.4 +/- 0.04 mg/dL. However, no significant difference was observed in the incidence of postoperative complications among the hypophosphatemia groups. The phosphorus level was positively correlated with the remnant liver volume (r = 0.389, P < 0.001), but it was negatively correlated with a postoperative increase in the ALP (r = -0.276, P = 0.014).

CONCLUSIONS

Hypophosphatemia developed very frequently after LDRH. However, transient hypophosphatemia was unlikely to lead to severe complications in healthy donors. Therefore, based on the serum level, oral or intravenous phosphorus replacement treatment might be more appropriate than routine aggressive replacement by TPN. In addition, although the factors responsible for posthepatectomy hypophosphatemia have not been identified, they might be substances that are associated with hepatic regeneration.

Gene expression-based recurrence prediction of hepatitis B virus-related human hepatocellular carcinoma

PURPOSE

The poor prognosis of hepatocellular carcinoma (HCC) is, in part, due to the high rate of recurrence even after "curative resection" of tumors. Therefore, it is axiomatic that the development of an effective prognostic prediction model for HCC recurrence after surgery would, at minimum, help to identify in advance those who would most benefit from the treatment, and at best, provide new therapeutic strategies for patients with a high risk of early recurrence.

EXPERIMENTAL DESIGN

For the prediction of the recurrence time in patients with HCC, gene expression profiles were generated in 65 HCC patients with hepatitis B infections.

RESULT

Recurrence-associated gene expression signatures successfully discriminated between patients at high-risk and low-risk of early recurrence (P=1.9 x 10(-6), log-rank test). To test the consistency and robustness of the recurrence signature, we validated its prognostic power in an independent HCC microarray data set. CD24 was identified as a putative biomarker for the prediction of early recurrence. Genetic network analysis suggested that SP1 and peroxisome proliferator-activated receptor-alpha might have regulatory roles for the early recurrence of HCC.

CONCLUSION

We have identified a gene expression signature that effectively predicted early recurrence of HCC independent of microarray platforms and cohorts, and provided novel biological insights into the mechanisms of tumor recurrence.

Laparoscopic surgery for submucosal tumors located at the esophagogastric junction and the prepylorus

BACKGROUND

Laparoscopic partial gastric resection is widely accepted as a treatment for gastric submucosal tumors (SMTs). However, SMTs of either end of the stomach are generally managed by subtotal gastrectomies or total gastrectomies. This study was conducted to evaluate surgical techniques for management of SMTs located at the ends of the stomach.

METHODS

Among 63 patients who were diagnosed and underwent laparoscopic surgery for gastric SMTs at Seoul National University Bundang Hospital from May 2003 to May 2007, 11 SMTs located at the ends of the stomach were identified. The clinicopathologic results of these 11 SMTs were analyzed.

RESULTS

Laparoscopic partial wedge resections or tumor excisions were successfully performed on all patients except for those who had prepyloric tumors. Six men and five women had SMTs at the ends of the stomach. The patients ranged in age from 21-63 years (mean 43.4 +/- 13.5 years). Of six esophagogastric junctional tumors that showed low, homogeneous contrast enhancement on computed tomography (CT) scans, five were treated by laparoscopic transgastric enucleation and one by tumor-everting resection. One esophagogastric junctional tumor that leaned toward the fundus and showed a 6-cm-diameter endophytic mass with heterogeneous enhancement on CT scan was resected by laparoscopic wedge resection. The mean operation time was 100 min (range 60-210 min). Three laparoscopy-assisted distal gastrectomies and one laparoscopic wedge resection were performed on SMTs located near the prepyloric antrum. There were no intra- or postoperative complications. Duration of postoperative hospital stay ranged from 4-7 days.

CONCLUSION

Laparoscopic local resection is an effective treatment for SMTs located at the esophagogastric junction and can be used instead of a total or proximal gastrectomy. However, gastrectomies should be considered for SMTs located near the pylorus because of the small volume of the lower third of the stomach.

Clinicopathological features and surgical outcomes of patients with remnant gastric cancer after a distal gastrectomy

BACKGROUND

The incidence of gastric cancer in the remnant stomach after distal gastrectomy is increasing. The aim of this study was to evaluate the clinicopathological features and surgical outcomes of remnant gastric cancer (RGC).

METHODS

We reviewed the medical records of 58 patients who underwent laparotomy for RGC at Seoul National University Hospital between 2000 and 2005.

RESULTS

The mean interval between the first and second operations was 12.5 years, and the rate of RGC diagnosis by tests included the follow-up program was 41.4%. The 45 RGCs occurring after distal gastrectomy for initial gastric cancer had a shorter interval and were more frequently located at the non-anastomotic site than those following benign lesions (P <0.001 and P = 0.010). Of all patients, 41 (70.7%) underwent, and the overall 3-year survival rate was 62.4%. An early stage of the initial gastric cancer, no symptoms at diagnosis, curative resection, tumor size smaller than 6 cm, and an early TNM stage of the RGC were associated with longer survival; the initial gastric disease, the interval and the location of RGC were not.

CONCLUSION

The successful curative resection and an early stage of the RGC led to good outcomes. In considering the different latency periods of the two initial gastric diseases, appropriate follow-up programs should be developed.