Distribution of lymph node metastasis including micrometastasis in gastric cancer with submucosal invasion

Occult Tumour Cells in Lymph Nodes from Gastric Cancer Patients: Should Isolated Tumour Cells Also Be Considered?

INTRODUCTION

Regional lymph node metastasis is an important prognostic factor for patients with gastric cancer. Occult tumour cells (OTCs), including either micrometastases (MMs) or isolated tumour cells (ITCs), may be a key factor in the development of cancer recurrence in pN0 patients.

AIMS

We aimed to determine the frequency and prognostic significance for disease recurrence of OTCs.

MATERIALS AND METHODS

This retrospective cohort study included all consecutive patients with pN0 gastric adenocarcinoma between January 2000 and December 2011 (n = 73). Immunohistochemistry using the pan-cytokeratin antibody AE1/AE3 was used to detect OTCs in 1257 isolated lymph nodes.

RESULTS

OTCs were identified in 30 patients (41%), including 20 cases with MMs (27%) and 10 cases with ITCs (14%). Disease recurrence and cancer-related death were observed in 24 (33%) and 20 patients (27%), respectively, and both were significantly associated with the detection of OTCs. A significant difference was also observed for the mean survival time between patients with OTCs and those without OTCs [100 vs 158 months (p = 0.015)]. The presence of OTCs was statistically significantly associated with the Lauren classification, tumour size and lymphatic permeation. Multivariate analyses revealed that only age, T stage and the presence of ITCs in lymph nodes were independent factors for recurrence. The presence of ITCs increased the risk for recurrence by 11.1-fold.

CONCLUSIONS

In a significant proportion of patients diagnosed as stage pN0, OTCs may be identified in lymph nodes if carefully searched for, which can negatively affect their prognosis. The presence of ITCs was found to be an independent factor for recurrence and after proper validation should be considered during lymph node assessment for prognosis definition.

Occult Tumor Cells in Lymph Nodes of Patients with Gastric Cancer: A Systematic Review on Their Prevalence and Predictive Role

BACKGROUND AND AIMS

The presence of lymph node (LN) metastasis is a key prognostic factor for gastric adenocarcinoma. However, even among patients without LN metastasis (N0), recurrence may occur. In some of these cases, occult tumor cells (OTC) are thought to play an important role. We aimed to determine the prevalence of OTC and its clinical relevance.

METHODS

We conducted a systematic review of studies in English published until September 2013 that addressed OTC prevalence and/or its clinical relevance. The studies were retrieved from the MEDLINE database.

RESULTS

We included 42 studies. The most frequently used methods for detecting OTC were immunohistochemical examination (IHC) and/or polymerase chain reaction (PCR) with a wide range of markers. Using IHC for OTC detection, in patients and in LN, the prevalence varied from 9 to 88% and 0.4 to 42%, respectively. With PCR, it ranged from 17 to 46% in patients, and from 3 to 33% in LN. In the studies assessing the predictive role of OTC in gastric cancer recurrence (n=24), 8 studies found no statistical association, while 18 concluded that OTC presence was associated with poorer prognosis. However, only 6 studies presented a significantly different 5-year survival rate between patients with and without LN micrometastasis.

CONCLUSIONS

OTC seems to occur in gastric cancer patients with a variable prevalence, depending on the definition, methods and setting. The majority of the retrieved studies (75%) evaluating the predictive role of OTC conclude that its presence is associated with a worse prognosis.

Resection of distal gastric tube cancer with sentinel node biopsy: a case report and review of the literature

Background

The frequency of gastric tube cancershas increased with advances in surgical techniques and improvement of survival rates in patients with esophageal cancer. However, a standard surgical treatment has not yet been established. Total resection of the gastric tube with lymphadenectomy has been considered a radical treatment, while repeat surgery with both laparotomy and thoracotomy has been associated with severe complications, including anastomotic leakage, recurrent nerve paralysis, bronchotracheal injury, and damage to other organs.

Case presentation

We present a successful case of a gastric tube cancer that was treated with surgical resection in combination with sentinel node biopsy. The tumor was diagnosed as a type 0-IIc lesion with ulceration, and was located proximal to the pyloric ring. Endoscopic submucosal dissection was not indicated because the primary lesion was submucosally invasive, and undifferentiated. By the dye-guided method, sentinel nodes were detected along the right gastroepiploic artery and vein. Intraoperative pathological examination revealed no metastasis of the sentinel nodes. Resection of the distal gastric tube was safely performed with a Roux-en-Y reconstruction, preserving the right gastroepiploic artery and vein and the perfusion of the proximal gastric tube.

Conclusion

We suggest distal resection of the gastric tube with sentinel node biopsy as a novel surgical method for a cT1N0 gastric tube cancer located in the abdomen.

Clinical impact of the extent of lymph node micrometastasis in undifferentiated-type early gastric cancer

OBJECTIVE

Lymph node (LN) metastasis is one of the most important prognostic factors for undifferentiated-type early gastric cancer (EGC). The aim of this study was to examine expansion of micrometastasis in regional LNs to clarify the importance of lymphadenectomy for undifferentiated-type EGC.

METHODS

Clinicopathological features of 307 patients with undifferentiated-type EGC who underwent gastrectomy with lymphadenectomy between 1997 and 2010 at the Department of Surgical Oncology, Osaka City University, were retrospectively reviewed. Micrometastasis in LNs was detected by immunohistochemistry using anticytokeratin antibody.

RESULTS

The incidence of LN metastasis was 1.8% in patients with mucosal (pT1a) tumors and 17.3% in those with submucosal (pT1b) tumors. Multivariate analysis revealed that lymphatic invasion and tumor depth were independently related to LN metastasis. Micrometastasis was found in 41 (13.3%) patients. Twenty-two patients with pN0 had micrometastasis in the perigastric region. Micrometastasis had spread to the area along the left gastric or common hepatic artery in 12 patients. Patients with an upgraded stage by micrometastasis had significantly worse disease-free survival.

CONCLUSIONS

LN micrometastasis was observed beyond the perigastric LNs and correlated with poor outcomes in patients with undifferentiated-type EGC. These data underscore the importance of adequate lymphadenectomy for patients with undifferentiated-type EGC. © 2014 S. Karger AG, Basel.

Detection and clinical significance of lymph node micrometastasis in gastric cardia adenocarcinoma

OBJECTIVES

Lymph node micro metastasis was investigated in gastric cardia adenocarcinoma (GCA) patients without lymph node metastasis on routine pathological examination. The relationship between micrometastasis and clinicopathological features was also evaluated.

METHODS

A total of 349 lymph nodes were obtained from 45 patients with GCA. Micrometastases were detected by immunohistochemical staining for the markers cytokeratin 19 (CK19) and CD44 variant 6 (CD44v6).

RESULTS

A total of 33 lymph nodes (9.5%) from 15 patients (33.3%) were positive for CK19. Of these, 27 lymph nodes (7.7%) from 12 patients (26.7%) were also positive for CD44v6. Micrometastasis was significantly related to depth of tumour invasion and Lauren classification (intestinal or diffuse). The recurrence rate was significantly higher and 2-year survival rate significantly lower in patients with than in those without lymph node micrometastasis, showing the necessity of detecting micrometastasis in GCA patients who test negative for lymph node metastasis on routine examination.

CONCLUSION

CK19 and CD44v6 were shown to be good markers for micrometastasis detection.

Frequency and predictive factors of lymph node metastasis in mucosal cancer

Purpose

The incidence of lymph node metastasis has been reported to range from 2.6 to 4.8% in early stage gastric cancer with mucosal invasion (T1a cancer). Lymph node metastasis in early stage gastric cancer is known as an important predictive factor. We analyzed the prediction factors of lymph node metastasis in T1a cancer.

Materials and Methods

A total of 9,912 patients underwent radical gastrectomy due to gastric cancer from October 1994 to July 2006 in the Department Of Surgery at Samsung Medical Center. We did a retrospective analysis of 2,524 patients of these patients, ones for whom the cancer was confined within the mucosa.

Results

Among the 2,524 patients, 57 (2.2%) were diagnosed with lymph node metastasis, and of these, cancer staging was as follows: 41 were N1, 8 were N2, and 8 were N3a. Univariate analysis of clinicopathological factors showed that the following factors were significant predictors of metastasis: tumor size larger than 4 cm, the presence of middle and lower stomach cancer, poorly differentiated adenocarcinoma and signet-ring cell carcinoma, diffuse type cancer (by the Lauren classification), and lymphatic invasion. Multivariate analysis showed that lymphatic invasion and tumor larger than 4 cm were significant factors with P<0.001 and P=0.024, respectively.

Conclusions

The frequency of lymph node metastasis is extremely low in early gastric cancer with mucosal invasion. However, when lymphatic invasion is present or the tumor is larger than 4 cm, there is a greater likelihood of lymph node metastasis. In such cases, surgical treatments should be done to prevent disease recurrence.

Prognostic factors for patients after curative resection for proximal gastric cancer

The factors influencing the long-term survival of patients with proximal gastric cancer (PGC) after curative resection were investigated. Data from 171 patients who underwent curative resection for PGC were retrospectively analyzed. The patients were grouped according to the clinicopathological factors and operative procedures. The tumor depth (T stage) and lymph node metastasis (pN stage) were graded according to the fifth edition of TNM Staging System published by UICC in 1997. The metastatic lymph node ratio (MLR) was divided into four levels: 0%, <10%, 10%-30% and >30%. The data of survival rate were analyzed by Kaplan-Meier method (log-rank test) and Cox regression model. The 5-year overall survival rate of 171 patients was 37.32%. The univariate analysis demonstrated that the survival time of the postoperative patients with PGC was related to tumor size (chi2=4.57, P=0.0325), gross type (chi2=21.38, P<0.001), T stage (chi2=27.91, P<0.001), pN stage (chi2=44.72, P<0.001), MLR (chi2=61.12, P<0.001), TNM stage (chi2=44.91, P<0.001), and range of gastrectomy (chi2=4.36, P=0.0368). Multivariate analysis showed that MLR (chi2=10.972, P=0.001), pN stage (chi2=6.640, P=0.010), TNM stage (chi2=7.081, P=0.007), T stage (chi2=7.687, P=0.006) and gross type (chi2=6.252, P=0.012) were the independent prognostic factors. In addition, the prognosis of patients who underwent total gastrectomy (TG) was superior to that of patients who underwent proximal gastrectomy (PG) for the cases of tumor>or=5 cm (chi2=6.31, P=0.0120), Borrmann III/IV (chi2=7.96, P=0.0050), T4 (chi2=4.57, P=0.0325), pN2 (chi2=5.52, P=0.0188), MLR 10%-30% (chi2=4.46, P=0.0347), MLR>30% (chi2=13.34, P=0.0003), TNM III (chi2=14.05, P=0.0002) or TNM IV stage (chi2=4.37, P=0.0366); and combining splenectomy was beneficial to the cases of T3 (chi2=5.68, P=0.0171) or MLR>30% (chi2=6.11, P=0.0134). It was concluded that MLR, pN stage, TNM stage, T stage, and gross type had advantages in providing a precise prognostic evaluation for patients undergoing curative resection for PGC, in which MLR was the most valuable index. TG and combining splenectomy were useful to improve the prognosis to patients with PGC of TNM III/IV stage, serosa invasion, or extensive regional lymph node metastasis.

Risk factors for lymph node metastasis from gastric cancers with submucosal invasion

BACKGROUND

Accurate prediction of the metastatic status of lymph nodes (LNs) is clinically important for selecting treatment strategies in patients with gastric cancer with submucosal invasion (GCSM). In this study, we determined the risk factors for lymph node metastasis (LNM), including micrometastasis, in patients with GCSM.

MATERIALS AND METHODS

A total of 5610 LNs dissected from 189 patients with GCSM who had undergone a standard gastrectomy were immunostained with CAM 5.2 monoclonal antibody to detect LN micrometastasis. Clinicopathological risk factors for lymph node metastasis (LNM), including micrometastasis, were determined.

RESULTS

LNM was detected in 216 LNs (107 macroscopic metastases, 72 micrometastases, and 37 isolated tumor cells) in 55 (29.1%) of the 189 patients with GCSM. A multivariate analysis revealed that a tumor size of more than 20 mm, a mixed- or undifferentiated-type histology, a vertical tumor invasion depth in the submucosal layer (VTIDSM) of more than 0.5 mm, and the presence of lymphatic vessel invasion (LVI) were independent risk factors for LNM. The incidences of LNM in patients with 0, 1, 2, 3, and 4 risk factors were 0, 4.5, 11.4, 36.1, and 52.9%, respectively. Among the patients with only 1 or 2 risk factors, all the metastatic lesions were located only in the first tier. On the other hand, LNM in the second tier was also detected in 24.5% of the patients with more than 3 risk factors.

CONCLUSIONS

Tumor size, histologic type, VTIDSM, and LVI are important risk factors for predicting the presence and extent of LNM in patients with GCSM.

Pattern of lymph node involvement in proximal gastric cancer

BACKGROUND

The operative methods for proximal gastric cancer differ depending on the institution, thus there is no optimal therapeutic strategy. A splenic hilum lymph node (No. 10) dissection is necessary for D2 operation for proximal gastric cancer, which means it requires splenectomy. However, unnecessary splenectomy should be avoided.

METHODS

A total of 127 proximal gastric cancer cases from our institution were studied retrospectively. In addition, 1,569 cases were collected from the literature and were used as pooled data for further analysis. All cases were examined for the depth of tumor invasion and lymph node metastasis.

RESULTS

A retrospective analysis revealed that proximal gastric cancer within submucosa (40 cases) had no N2 lymph node metastasis in our study. The 5-year overall survival of all cases was 25.2% and the disease-free survival was 23.6%. From the pooled data analysis, No. 10 lymph node metastasis was observed in 0.9% of the patients with submucosa proximal gastric cancer. Furthermore, there was no No. 4d lymph node metastasis when the depth of cancer was limited to within the subserosa.

CONCLUSIONS

Although a randomized, controlled trial concerning survival is necessary, according to this study, there is a possibility that limited resection might be accepted for proximal gastric cancer according to the depth of wall invasion.

[Surgical treatment of gastric carcinoma]

The gastric cancer is the most common cancer in Korea. The only treatment modality showing improved survival for gastric cancer is curative surgical resection, which comprises the resection of stomach, proper lymphadenectomy, and reconstruction. However, specific surgical procedures should be decided according to the location of the cancer, advancement of the tumor, and patients condition. Surgical treatment for gastric cancer has been developed toward two directions that are minimal invasive surgery for early gastric cancer and multi-disciplinary approach for advanced gastric cancer. Laparoscopic surgery for early gastric cancer has been accepted for minimally invasive surgery. Moreover, the advancement of diagnostic tools to assess biological aggressiveness of the tumor enables physicians to perform endoscopic resection or minimized resection for early gastric cancer. Recently, surgeons try to extend the application of laparoscopic gastric resection and D2 lymphadenectomy to advanced gastric cancer. However, technical and oncological evidences based on clinical trials should be filed up before adopting it as a standard therapy. In case of advanced gastric cancer, in addition to radical surgery, various treatment modalities including chemotherapy, radiation, and molecular target therapy also have been applied in many clinical trials. However, it should be stressed that a prerequisite for precise evaluation of the efficacy of these combined treatment modalities would be the standardization of surgical procedure.

Predicting lymph node status in early gastric cancer

Accurate prediction of lymph node (LN) status is of crucial importance for appropriate treatment planning in patients with early gastric cancer (EGC). However, there is no definitive consensus yet on which patient and/or tumor characteristics are associated with LN metastasis. A systematic search for studies investigating the relationship between patient and/or tumor characteristics and LN metastasis in EGC was performed in PubMed/MEDLINE. Patient and/or tumor characteristics associated with LN metastasis were identified by meta-analyzing results of individual studies. Forty-five studies were included. Variables significantly associated with LN metastasis in gastric cancer limited to the mucosa were: age younger than 57 years, tumor location in the middle part of the stomach, larger tumor size, macroscopically depressed tumor type, tumor ulcerations, undifferentiated tumors, diffuse tumor type according to the Lauren classification, lymphatic tumor invasion, tumors with a proliferating cell nuclear antigen (PCNA) labeling index of more than 25%, and matrix metalloproteinase-9-positive tumors. Variables significantly associated with LN metastasis in gastric cancer limited to the submucosa were: female sex, tumor location in the lower part of the stomach, larger tumor size, undifferentiated tumors, increasing depth of submucosal invasion, lymphatic tumor invasion, vascular tumor invasion, increased submucosal vascularity, tumors with a PCNA labeling index of more than 25%, tumors with a gastric mucin phenotype, and vascular endothelial growth factor-C-positive tumors. We identified several variables associated with LN metastasis in EGC. These variables should be included in future research, in order to assess which of these variables remain as significant predictors of LN metastasis.

Prognostic impact of metastatic lymph node ratio in advanced gastric cancer from cardia and fundus

AIM: To investigate the prognostic impact of the metastatic lymph node ratio (MLR) in advanced gastric cancer from the cardia and fundus.

METHODS: Two hundred and thirty-six patients with gastric cancer from the cardia and fundus who underwent D2 curative resection were analyzed retrospectively. The correlations between MLR and the total lymph nodes, positive nodes and the total lymph nodes were analyzed respectively. The influence of MLR on the survival time of patients was determined with univariate Kaplan-Meier survival analysis and multivariate Cox proportional hazard model analysis. And the multiple linear regression was used to identify the relation between MLR and the 5-year survival rate of the patients.

RESULTS: The MLR did not correlate with the total lymph nodes resected (r = -0.093, P = 0.057). The 5-year overall survival rate of the whole cohort was 37.5%. Kaplan-Meier survival analysis identified that the following eight factors influenced the survival time of the patients postoperatively: gender (χ² = 4.26, P = 0.0389), tumor size (χ² = 18.48, P < 0.001), Borrmann type (χ² = 7.41, P = 0.0065), histological grade (χ² = 5.07, P = 0.0243), pT category (χ² = 49.42, P < 0.001), pN category (χ² = 87.7, P < 0.001), total number of retrieved lymph nodes (χ² = 8.22, P = 0.0042) and MLR (χ² = 34.3, P < 0.001). Cox proportional hazard model showed that tumor size (χ² = 7.985, P = 0.018), pT category (χ² = 30.82, P < 0.001) and MLR (χ² = 69.39, P < 0.001) independently influenced the prognosis. A linear correlation between MLR and the 5-year survival was statistically significant based on the multiple linear regression (β = -0.63, P < 0.001). Hypothetically, the 5-year survival would surpass 50% when MLR was lower than 10%.

CONCLUSION: The MLR is an independent prognostic factor for patients with advanced gastric cancer from the cardia and fundus. The decrease of MLR due to adequate number of total resected lymph nodes can improve the survival.

Lymph node micrometastasis in node negative early gastric cancer

AIMS

The clinical significance of lymph node micrometastasis for histologically node negative gastric cancer is not well documented. This study was to assess the incidence and to clarify the risk factors of lymph node micrometastasis in patients with node negative early gastric cancer (EGC).

METHODS

We investigated the lymph node micrometastasis with using an anticytokeratin immunohistochemical stain in 90 patients with node negative EGC who underwent curative resection between 1991 and 2000.

RESULTS

Among 3526 nodes from 90 patients, there were 17 cytokeratin immunohistochemical stain positive nodes from nine patients. The incidence of micrometastasis was higher in patients with lymphatic invasion (p=0.012), venous invasion (p=0.026) and larger tumor (p=0.003). The independent risk factors for lymph node micrometastasis were lymphatic invasion (p=0.004, RR=22.915, 95% CI = 2.709 ~ 193.828) and tumor size (p=0.029, RR=1.493, 95% CI = 1.042 ~ 2.138). Although there were 10 deaths during the follow-up period of mean 67.6 months (1 month ~ 147 months), there was no death from a cancer recurrence.

CONCLUSIONS

The incidence of lymph node micrometastasis in patients with node negative early gastric cancer was 10%, and the independent risk factors for micrometastasis were lymphatic invasion and tumor size.

Detection of sentinel and non-sentinel lymph node micrometastases by complete serial sectioning and immunohistochemical analysis for gastric cancer

BACKGROUND

We investigated the presence and distribution of the sentinel and the non-sentinel node micrometastases using complete serial sectioning and immunohistochemical staining (IHC), to inspect whether lymph node micrometastases spread to the sentinel lymph nodes first.

METHODS

A total of 35 patients, who underwent gastrectomy with a sentinel lymph node biopsy for gastric cancer, were enrolled in this study. Total of 1028 lymph nodes of 35 patients having gastric cancer without metastasis of lymph node by permanent section with hematoxylin and eosin staining (H&E) were selected. There were 252 sentinel nodes and the other 776 were non-sentinel nodes. All nodes were sectioned serially and stained alternately with H&E and IHC. Lymph node micrometastases was defined as proving to be positive first either the IHC or the complete serial sectioning.

RESULTS

Micrometastases were detected in 4 (11%) of the 35 patients, 6 (0.58%) of 1028 nodes. Of these 4 patients, 3 had micrometastases exclusively in sentinel nodes, and the other had micrometastasis in both sentinel and non-sentinel nodes. There was no patient who had the micrometastases only in non-sentinel nodes.

CONCLUSION

These results support the concept that lymph node micrometastasis of gastric cancer spreads first to sentinel nodes.

Prognostic significance of gastric cancer metastasis in second-tier lymph nodes detected on reverse transcriptase-polymerase chain reaction and immunohistochemistry

To determine the prognostic significance of the methods used to determine the presence of metastasis in second-tier lymph nodes of patients with gastric cancer, the authors studied lymph nodes surgically removed from 100 patients with gastric cancer (55 with early cancer, 45 with progressive). The results of HE staining were compared with those of immunohistochemistry using the anticytokeratin (CK) antibody and reverse transcriptase-polymerase chain reaction (RT-PCR) assays. Lymph node 7 or 8a was obtained intraoperatively, then mRNA was extracted using an immunobeads method, and RT-PCR with CK19 mRNA was performed. The P for Cox regression analysis for metastasis detected by HE staining, CK staining, and RT-PCR of all 100 cases was 0.312, 0.426, and 0.021, respectively, while for second-tier lymph nodes it was 0.154, 0.013, and 0.006, respectively. In conclusion, RT-PCR and CK staining for detection of metastasis in second-tier lymph nodes were more reliable prognostic indicators than conventional HE staining.

Symptom evaluation of long-term postoperative outcomes after pylorus-preserving gastrectomy for early gastric cancer

BACKGROUND

Since the early 1990s, pylorus-preserving gastrectomy (PPG) has been used in the treatment of patients with early gastric cancer in order to reduce postprandial symptoms. To date, there have been few reports of long-term symptom evaluation following this procedure. The aim of this study was to evaluate long-term postoperative outcomes after PPG.

METHODS

Three hundred and ninety-seven patients with early gastric cancer were enrolled in this study: 194 patients who underwent PPG and 203 who underwent distal gastrectomy with Billroth-I reconstruction (DGBI). We compared the symptoms for the two groups in a questionnaire on postoperative functional outcomes, endoscopy findings and the appearance of gallstones after surgery.

RESULTS

The incidence of symptoms suggesting early dumping syndrome was significantly lower in the PPG group compared with the DGBI group (P < 0.05). The incidences of disturbed bowel habit and frequent flatus were significantly lower in the PPG than in the DGBI group. The average relative body weight (actual BW/ BW immediately before the surgery) was significantly better in the PPG than in the DGBI group (P < 0.001).

CONCLUSION

The long-term results show that PPG has clear advantages over DGBI in terms of postoperative symptoms and functional outcomes. These results imply that PPG should be the recommended procedure for early gastric cancers located in the middle third of the stomach.

Billroth 1 versus Roux-en-Y reconstructions: a quality-of-life survey at 5 years

BACKGROUND

In the majority of gastric surgical units across Japan, Billroth 1 is the preferred method of anastomosis following subtotal distal gastrectomy for gastric cancer. However, across Europe and North America, reconstruction using a Roux-en-Y anastomosis is more common. There is a lack of comparative studies of the two methods focusing on long-term outcome. This study evaluated patient outcome, in terms of adverse gastrointestinal complaints and quality of life, at 5 years following surgery.

METHODS

A total of 652 patients had a subtotal distal gastrectomy for early gastric cancer between January 1993 and December 1999. We studied 229 patients with reconstruction by the Billroth 1 procedure and 214 patients with the Roux-en-Y procedure. All patients had an abdominal ultrasound and endoscopy as part of their follow-up. Quality of life was assessed by questionnaire.

RESULTS

We had an 87% response rate from the questionnaire assessment. The results demonstrated that patients were less likely to experience symptoms of either early or late dumping after Roux-en-Y anastomosis than after Billroth 1. In addition, there were significantly fewer patients with gastritis on endoscopy in the Roux-en-Y group. There was no significant difference in the average relative body weight between the groups. However, patients were more likely to develop gallstones after a Roux-en-Y than after a Billroth 1 reconstruction.

CONCLUSION

The results from this study show that, at 5 years, both symptomatically and functionally, Roux-en-Y reconstruction was superior to the Billroth I method after subtotal distal gastrectomy for gastric cancer. However, the overall outcome in both groups was good, with patient satisfaction scores of around 75% in each group.

Effect of lymph node micrometastases on prognosis of gastric carcinoma

AIM: To evaluate the relationship between lymph node micrometastases and prognosis of patients with gastric carcinoma and to evaluate the significance of the new assessment of nodal status in determining the pN categories in the 5th edition of the UICC TNM classification.

METHODS: A total of 850 lymph nodes from 30 patients with gastric carcinoma who underwent gastrectomy with lymphadenectomy were assessed by reverse transcription polymerase chain reaction assay in addition to histologic examination. Cytokeratin-20 gene marker was used in this assay.

RESULTS: Routine examination by HE staining confirmed metastasis in 233 lymph nodes from 20 patients. All these 233 lymph nodes were cytokeratin-20 positive. Moreover, lymph node micrometastases were detected in an additional 67 lymph nodes in 12 of these 20 patients. Lymph node micrometastases were also detected in 10 lymph nodes from 2 of 10 patients who had no obvious metastases identified by HE staining. Totally, lymph node micrometastases were identified by the reverse transcription polymerase chain reaction assay in 77 (12.5%) lymph nodes from 14 (46.7%) patients with gastric carcinoma. Of 27 patients who underwent curative resection, 7 (25.9%) were up-staged (fromIB stage to II stage in 1 patient, from IB stage to IIIA stage in 1 patient, from II stage to IIIA stage in 1 patient, from IIIA stage to IIIB stage in 1 patient, from IIIA stage to IV stage in 1 patient, from IIIB stage to IV stage in 2 patients). In a median follow-up of 32 (range 8-36) mo, Kaplan-Meier survival analysis showed significant improvements in median survival (22.86 ± 3.17 mo, 95% CI: 16.64-29.08 mo vs 18.00 ± 7.4 mo, 95% CI: 3.33-32.67 mo) of patients with negative lymph node micrometastases over patients with positive lymph node micrometastases (log-rank, P < 0.05).

CONCLUSION: Lymph node micrometastases have a significant impact on the current staging system of gastric carcinoma, and are significant risk factors for prognosis of patients with gastric carcinoma.

Survival of early gastric cancer in a specialized European center. Which lymphadenectomy is necessary?

PURPOSE

A clinicopathological study of early gastric cancer has been carried out in a single experienced surgical unit to identify prognostic indicators for survival and factors related to lymph nodes metastasis and document a survival benefit of D2 gastrectomy.

METHODS

A retrospective review of our database from January 1990 to December 2004 revealed 189 patients with early gastric cancer undergoing surgical resection with either D1 or D2 lymph node dissection. Clinicopathological factors analyzed included Lauren's histological type, histological differentiation, size, mucosal versus submucosal invasion, venous invasion, number of lymph node involved, and extent of nodal dissection performed. Factors related to increased risk of nodal metastases and predicting 5- and 10-year disease-specific survival were evaluated by univariate and multivariate analysis.

RESULTS

Median follow-up time was 77 months. Lymph node involvement was documented in 21.1% of patients. A D2 gastrectomy was performed in 56% of patients. The cumulative 10-year survival rate was 92.5%; it was strictly related to nodal metastases (p = .0014). Poor differentiation, size larger than 2 cm, and submucosal depth of invasion were related to increased risk of nodal metastases but not to decreased survival. Overall, 10-year survival after D2 gastrectomy was higher than after D1 gastrectomy (95 versus 87.5%), but this difference was not statistically significant (p = .80). No survival benefit was documented for D2 gastrectomy in subsets of patients with increased risk of nodal metastasis.

CONCLUSION

In this retrospective analysis a survival benefit of D2 gastrectomy was not documented either in the overall population or in subset analyses of patients with increased risk of nodal metastasis.

Diagnostic accuracy of multidetector row computed tomography in T- and N staging of gastric cancer with histopathologic correlation

PURPOSE

To evaluate the diagnostic accuracy of multidetector row computed tomography (MDCT) for the preoperative T- and N staging of gastric cancer.

MATERIALS AND METHODS

Eighty-four consecutive patients with gastric cancer underwent preoperative MDCT. Except for 15 patients who did not undergo surgery, 69 patients were included in our study. Two radiologists independently evaluated the T- and N staging on the axial CT images alone and in combination with the MPR images. For N staging, the new TNM and Japanese classifications were independently used. Differences in staging accuracy for T- and N staging were assessed using the McNemar test.

RESULTS

The overall T staging accuracy of the axial and combined axial and MPR images was as follows: 67% (47 of 70 cancers) versus 77% (54 of 70 cancers) (P=0.039). The overall N staging accuracy of the axial and combined axial and MPR images was as follows: 59% (41 of 69 cancers) versus 67% (46 of 69 cancers) (P=0.180, Japanese classification) and 54% (37 of 69 cancers) versus 59% (41 of 69 cancers) (P=0.109, TNM classification).

CONCLUSIONS

Using MPR images enables more accurate preoperative T staging of gastric cancer, but not for N staging in either classification system.

Lymph node micrometastasis and its correlation with MMP-2 expression in gastric carcinoma

AIM: To examine matrix metalloproteinase-2 (MMP-2) expression in gastric cancer tissues and to evaluate its relationship with lymph node micrometastasis.

METHODS: The authors studied 850 lymph nodes resected from 30 patients with gastric carcinoma who underwent gastrectomy with lymphadenectomy using reverse transcription polymerase chain reaction (RT-PCR) assay in addition to H-E staining. MMP-2 expression of the tumor tissues was detected by immunohistochemical technique (EliVision^TM plus).

RESULTS: MMP-2 expression was positive in 21 (70%) cases and negative in 9 (30%) cases. No significant correlations were found between MMP-2 expression and other variables such as age, gender, tumor location, tumor diameter, Lauren classification and lymphatic invasion. In contrast, MMP-2 expression correlated significantly with depth of tumor infiltration (P = 0.022), lymph node metastasis (P = 0.030) and tumor differentiation (P = 0.043). Lymph node micrometastases were detected in 77 (12.5%) lymph nodes of 14 (46.7%) gastric carcinoma patients. MMP-2 expression was positive in 12 (85.7%) of the 14 patients with lymph node micrometastasis, and in 9 (56.3%) of the 16 patients without lymph node micrometastasis (P = 0.118).

CONCOUSION: Our results demonstrate that MMP-2 expression has significant correlation with tumor invasion, tumor differentiation and lymph node metastases. MMP-2 expression may be an important biological characteristics and significant prognostic parameter of gastric carcinoma. We also conclude that MMP-2 may participate in the development of lymph node micrometastasis of gastric carcinoma. Further investigations are needed to draw a conclusion.

Significance of isolated tumor cells in lymph nodes among gastric cancer patients

PURPOSE

To determine the frequency and prognostic impact of isolated tumor cells (ITC) in regional lymph nodes judged to be tumor free in conventional histopathology among gastric cancer patients.

METHODS

Among 161 patients who underwent gastrectomy and D2-lymphadenectomy, 56 were staged pN0(35%). Archival paraffin blocks of 1148 resected regional lymph nodes of those pN0 patients were reevaluated for ITC using monoclonal antibody Ber-EP4. Patients with and without ITC were compared with regard to the distribution of various clinicopathological factors. Prognostic impact of ITC was tested in uni- and multivariate analysis.

RESULTS

Of 56 pN0 patients, 33 (59%) exhibited single Ber-Ep4 immunoreactive cells or small cell clusters in at least one lymph node. The occurrence of ITC was not dependent on other clinicopathological factors. ITC impaired patients' prognoses significantly in uni- as well as multivariate analyses [estimated 5-year survival rate: 82% for pN0((i-))vs 58% for pN0((i+))(p = 0.059) and 15% for pN1/2 (p = 0.0005 and p < 0.0001, respectively)].

CONCLUSION

ITC are a frequent event in apparently tumor-free lymph nodes of gastric cancer patients and are overlooked by conventional histopathology. They are encountered even in limited stages of disease and impair patients' prognoses. This should be borne in mind when advocating local resection for early gastric cancer.

Novel Operative Technique for Vagal Nerve- and Pyloric Sphincter-preserving Distal Gastrectomy Reconstructed by Interposition of a 5 cm Jejunal J Pouch with a 3 cm Jejunal Conduit for Early Gastric Cancer and Postoperative Quality of Life 5 Years after Operation

The importance of the vagal nerve and pyloric sphincter, the need for pouch reconstruction, and the ideal pouch volume are all matters of controversy. A novel operative technique for vagal nerve- and pyloric sphincter-preserving distal gastrectomy reconstructed by interposition of a 5 cm jejunal J pouch with a 3 cm jejunal conduit was developed as a function-preserving surgical technique to prevent postgastrectomy disorders. The application criteria and technique are outlined in this article. Postoperative quality of life was also investigated clinically. Twenty subjects who underwent this surgical operation (group A: 16 men and 4 women aged 41 to 70 years, mean age 59.5 years) were interviewed to inquire about postoperative gastrointestinal symptoms. These patients were compared with 44 others who underwent conventional distal gastrectomy with D2 lymphadenectomy (group B: 30 men and 14 women aged 43 to 73 years, mean age 62.6 years). Included were patients with early cancer [mucosal or submucosal 1 (SM1) cancer and no lymph node metastasis (N0)] in the middle or lower third of stomach (or both) who were either not eligible for endoscopic excision of gastric mucosa or for partial gastric excision in the mucosa = 3.5 cm or SM1 5.5 cm, or further in distance from the anal margin of the cancer to the pyloric sphincter. Cases in which the remnant stomach would become one-third or less of the original size were also applied. During excision with lymph nodes, the hepatic and celiac branches bifurcating from the anterior and posterior trunks of the vagal nerve were preserved. The antrum was severed 1.5 cm from the pyloric sphincter, preserving the arteria supraduodenalis. The substitute stomach was created as a 5 cm jejunal pouch with a 3 cm jejunal conduit for orthodromic peristaltic movement using an automatic suture instrument to complete a side-to-side anastomosis of the folded jejunum. The anal side of the gastric remnant was manually anastomosed with the jejunal J pouch, and anastomosis of the pyloric antrum with the jejunal conduit was manually completed by stratum anastomosis. Postoperatively, the procedure in group A alleviated gastrointestinal symptoms such as appetite loss, epigastric fullness, reflux esophagitis, early dumping syndrome, body weight loss, endoscopic reflux esophagitis, and endoscopic gastritis in the remnant stomach, postprandial stasis of the substitute stomach, and postgastrectomy cholecystolithiasis better than in group B. The results suggest that the proposed technique is a function-preserving gastric operation appropriate for preventing postgastrectomy disorder.