Optimal extent of lymph node dissection for remnant advanced gastric carcinoma after distal gastrectomy: a retrospective analysis of more than 3000 patients from the nationwide registry of the Japanese Gastric Cancer Association

BACKGROUND

No guidelines are available for defining the extent of lymph node (LN) dissection in patients with remnant gastric carcinoma (RGC). Hence, this retrospective study aimed to determine the optimal extent of LN dissection in patients with RGC.

METHODS

We retrospectively evaluated the therapeutic outcomes of node dissection for RGC from a nationwide registry. When the metastatic rate or 5-year survival rate exceeded 10%, dissection was recommended. We calculated the dissection index by multiplying the incidence of metastasis at that nodal station by the 5-year survival rate of patients with metastasis at the station. A dissection index of > 1.0 was considered significant.

RESULTS

We included 1133 patients with RGC (T2-T4 tumor) who had undergone distal gastrectomy as the primary surgery for the evaluation of the survival benefit of nodal dissection. Any regional node station was considered significant. When the primary surgery was for malignant disease, the index was high for Nos. 3 (10.2), 7 (9.5), 1 (7.1), and 9 (8.0) nodes. For nodes at the splenic hilum, the index value was 4.4, which was higher than that for the perigastric nodes (Nos. 4sa and 4sb). The index for No. 10 nodes was the highest (10.5) when tumors involved a greater curvature.

CONCLUSIONS

The therapeutic strategy for RGC remains the same, regardless of the histology of the primary disease during the initial surgery. Total gastrectomy and dissection of the perigastric LNs (Nos. 1-4), suprapancreatic LNs (Nos. 7-9 and 11), and LNs at the splenic hilum (No. 10) are justified.

Determinant Factors on Differences in Survival for Gastric Cancer Between the United States and Japan Using Nationwide Databases

Background

Although the incidence and mortality have decreased, gastric cancer (GC) is still a public health issue globally. An international study reported higher survival in Korea and Japan than other countries, including the United States. We examined the determinant factors of the high survival in Japan compared with the United States.

Methods

We analysed data on 78,648 cases from the nationwide GC registration project, the Japanese Gastric Cancer Association (JGCA), from 2004–2007 and compared them with 16,722 cases from the Surveillance, Epidemiology, and End Results Program (SEER), a United States population-based cancer registry data from 2004–2010. We estimated 5-year relative survival and applied a multivariate excess hazard model to compare the two countries, considering the effect of number of lymph nodes (LNs) examined.

Results

Five-year relative survival in Japan was 81.0%, compared with 45.0% in the United States. After controlling for confounding factors, we still observed significantly higher survival in Japan. Among N2 patients, a higher number of LNs examined showed better survival in both countries. Among N3 patients, the relationship between number of LNs examined and differences in survival between the two countries disappeared.

Conclusion

Although the wide differences in GC survival between Japan and United States can be largely explained by differences in the stage at diagnosis, the number of LNs examined may also help to explain the gaps between two countries, which is related to stage migration.

Five-year survival analysis of surgically resected gastric cancer cases in Japan: a retrospective analysis of more than 100,000 patients from the nationwide registry of the Japanese Gastric Cancer Association (2001-2007)

BACKGROUND

The aim of this retrospective study was to investigate the tumor characteristics, surgical details, and survival distribution of surgically resected cases of gastric cancer from the nationwide registry of the Japanese Gastric Cancer Association.

METHODS

Data from 118,367 patients with primary gastric carcinoma who underwent resection between 2001 and 2007 were included in the survival analyses. The 5-year survival rates were calculated for various subsets of prognostic factors.

RESULTS

The median age of the patients was 67 years. The proportions of patients with pathological stage (Japanese Gastric Cancer Association) IA, IB, II, IIIA, IIIB, and IV disease were 44.0%, 14.7%, 11.7%, 9.5%, 5.0%, and 12.4% respectively. The death rate within 30 days of operation was 0.5%. The 5-year overall survival rate in the 118,367 patients who were treated by resection was 71.1%. The 5-year overall survival rates of patients with pathological stage IA, IB, II, IIIA, IIIB, and IV disease were 91.5%, 83.6%, 70.6%, 53.6%, 34.8%, and 16.4% respectively. The 5-year disease-specific survival rates in the patients with pT1 (mucosa) disease after D1+ dissection of lymph node station no. 7 (D1 + α), D1+ dissection of lymph node station nos. 7, 8, and 9 (D1+ β), and D2 lymphadenectomy were 99.4%, 99.6%, and 99.1% respectively. The 5-year disease-specific survival rates in the patients with pT1 (submucosa) disease after D1 + α, D1 + β, and D2 lymphadenectomy were 97.3%, 98.1%, and 96.9% respectively.

CONCLUSION

Detailed analyses of the data from more than 100,000 patients show the recent trends of the outcomes of gastric cancer treatment in Japan and provide baseline information for use by medical communities around world.

Gastric cancer treated by endoscopic submucosal dissection or endoscopic mucosal resection in Japan from 2004 through 2006: JGCA nationwide registry conducted in 2013

BACKGROUND

The Japanese Gastric Cancer Association (JGCA) initiated a new nationwide gastric cancer registry in 2008 and reported the treatment outcomes of patients with primary gastric cancer who underwent surgical therapy in 2001 and 2003. However, the outcomes of endoscopic therapy have not been reported yet.

METHODS

The JGCA conducted a retrospective nationwide registry in 2013 to investigate the short-term and long-term outcomes of endoscopic mucosal resection or endoscopic submucosal dissection in patients with gastric cancer treated from January 2004 through December 2006. This registry used a computerized database with terminology in accordance with the JGCA classification (13th and 14th editions) and the Japanese Gastric Cancer Treatment Guidelines from 2010.

RESULTS

Accurate data on 12,647 patients were collected from 126 participating hospitals and analyzed. The treatment procedure was endoscopic submucosal dissection in 81% of the patients and endoscopic mucosal resection in 19%. En bloc and R0 resections were achieved in 89% and 79% of the patients respectively. The total proportion of patients who underwent curative resection was 69.2%; 43.8% of patients underwent curative resection for absolute indication lesions, and 25.4% underwent curative resection for expanded indication lesions. Emergency surgery was performed to treat bleeding or perforation in very few patients (0.3% and 0.4% respectively). The 5-year follow-up rate after endoscopic resection was 70%. The 5-year overall survival rate was 91.6% in patients with absolute indications and 90.3% in patients with expanded indications after curative resection and 86.5% in patients who underwent noncurative resection. The 5-year disease-specific survival rates were 99.9%, 99.7%, and 98.7% in patients with absolute indications who underwent curative resection, patients with expanded indications who underwent curative resection, and patients who underwent noncurative resection respectively.

CONCLUSION

Endoscopic resection of gastric cancer resulted in favorable short-term and long-term outcomes nationwide in Japan. Further efforts to increase the follow-up rate are needed.

Lung adenocarcinoma may be a more susceptive subtype to a dendritic cell-based cancer vaccine than other subtypes of non-small cell lung cancers: a multicenter retrospective analysis

OBJECTIVE

The J-SICT DC Vaccine Study Group provides dendritic cell (DC) vaccines for compassionate use under unified cell production and patient treatment regimens. We previously reported beneficial effects of DC vaccines on the overall survival of 62 patients with advanced non-small cell lung cancer (NSCLC) in a single-center analysis. Here, we extended analysis to 260 patients with NSCLC who were treated at six centers.

METHODS

Of the 337 patients who met the inclusion criteria, we analyzed 260 patients who received ≥5 peptide-pulsed DC vaccinations once every 2 weeks.

RESULTS

The mean survival time (MST) from diagnosis was 33.0 months (95 % confidence interval [CI]: 27.9-39.2), and that from time of first vaccination was 13.8 months (95 % CI 11.4-16.8). An erythema reaction at the injection site that was ≥30 mm in diameter was correlated most strongly with overall survival from the first vaccine (≥30 vs. < 30 mm: MST 20.4 vs. 8.8 months, P < 0.001). We reported a similar finding in our previous analysis of patients with advanced pancreatic cancer. Interestingly, although such findings were common between patients with adenocarcinoma and those with other subtypes, the former group experienced significantly prolonged overall survival and a higher response rate for erythema (56.3 vs. 37.3 %, respectively, P = 0.014).

CONCLUSIONS

This is the first multicenter study that suggests a possible clinical benefit of DC vaccines for patients with advanced NSCLC, especially those with adenocarcinoma. These findings suggest a specific potential responder population for DC vaccines and warrant further investigation in well-controlled prospective randomized trials.

Abstract 727: TSLP expression and high serum TSLP level indicate a poor prognosis in gastric cancer patients

Purpose: Thymic stromal lymphopoietin (TSLP) plays an important role in promoting tumor survival, by manipulating the immune response and angiogenesis. However, the clinical significance of TSLP in gastric cancer is unclear.

Method: Immunohistochemistry was used to investigate TSLP expression in non-cancerous gastric mucosa and gastric cancer tissue from patients with gastric cancer. Serum TSLP levels were measured using an enzyme-linked immunosorbent assay.

Results: Tumors with TSLP expression were significantly larger than those without TSLP expression. TSLP expression was observed more frequently in advanced (T2/T3/T4) than in early (T1) gastric cancer and in stage 3/4 than in stage 1/2. Lymph node metastasis, liver metastasis, positive peritoneal lavage cytology, lymphatic

invasion, and vascular invasion occurred significantly more often in TSLP-expressing than in non-expressing tumors. The prognosis of patients with TSLP-positive tumors was significantly worse than that of patients with TSLP-negative tumors. Patients with high serum TSLP concentrations also had a significantly worse prognosis than those with low concentrations. Multivariate analysis identified serum TSLP level as an independent prognostic indicator.

Conclusion: TSLP is closely related to the progression of gastric cancer and may predict

survival in these patients.

Citation Format: Joji Watanabe, Hiroaki Saito, Kozo Miyatani, Masahide Ikeguchi, Yoshihisa Umekita, Shinji Otani, Shunichi Tsujitani. TSLP expression and high serum TSLP level indicate a poor prognosis in gastric cancer patients. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 727.

[A Large Number of Circulating Tumor Cells(CTCs)Can Be Isolated from Samples Obtained by Using Leukapheresis Procedures]

We hypothesized that a large number of circulating tumor cells(CTCs)may be isolated from samples obtained by using the leukapheresis procedures that are utilized to collect peripheral blood mononuclear cells for dendritic cell vaccine therapy. We utilized the CellSearch System to determine the number of CTCs in samples obtained by using leukapheresis in 7 patients with colorectal cancer, 5 patients with breast cancer, and 3 patients with gastric cancer. In all patients, a large number of CTCs were isolated. The mean number of CTCs per tumor was 17.1(range 10-34)in colorectal cancer, 10.0(range 2-27)in breast cancer, and 24.0(range 2-42)in gastric cancer. We succeeded in culturing the isolated CTCs from 7 patients with colorectal cancer, 5 patients with breast cancer, and 3 patients with gastric cancer. In conclusion, compared to conventional methods, a large number of CTCs can be obtained by using leukapheresis procedures. The molecular analyses of the CTCs isolated by using this method should be promising in the development of personalized cancer treatments.

Abstract 2813: Survival benefit of an add-on dendritic cell vaccine for patients with inoperable pancreatic cancer receiving chemotherapy: a multicenter study

Purpose: Dendritic cell (DC)-based cancer vaccine may have a significant benefit to patients with advanced pancreatic cancer. However, variations among clinical studies make it hard to detect its clinical outcome. Here we statistically identified factors determining the clinical benefit using data obtained at seven Japanese institutions that employed the same DC preparation and treatment regimen.

Patients and Methods: Among the 354 patients who met the inclusion criteria, 255 patients who received standard chemotherapy combined with peptide-pulsed DC vaccines were analyzed.

Results: The mean survival time from diagnosis was 16.5 months (95%CI=14.4-18.5), and that from the first vaccination was 9.9 months (95%CI=8.0-12.9). Known prognostic baseline factors related to advanced pancreatic cancer, namely ECOG-PS, peritoneal metastasis, liver metastasis, and prognostic nutrition index (PNI) were also representative. Importantly, erythema reaction after vaccination was an independent and treatment-related predictive factor for better survival, and that OK432 might be a good adjuvant enhancing the antitumor immunity during DC vaccination.

Conclusion: This is the first report of a multicenter clinical study suggesting the feasibility and possible clinical benefit of an add-on DC vaccine in patients with advanced pancreatic cancer who are undergoing chemotherapy. These findings need to be addressed in well-controlled prospective randomized trials.

Citation Format: Masanori Kobayashi, Shimodaira Shigetaka, Kazuhiro Nagai, Masahiro Ogasawara, Hidenori Takahashi, Hirofumi Abe, Mitsugu Tanii, Masato Okamoto, Shun-ichi Tsujitani, Masaki Nagaya, Yoshikazu Yonemitsu, The DC vaccine study group of Japan Society of Innovative Cell Therapy (J-SICT). Survival benefit of an add-on dendritic cell vaccine for patients with inoperable pancreatic cancer receiving chemotherapy: a multicenter study. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2813. doi:10.1158/1538-7445.AM2014-2813

Pilot study of preoperative immunonutrition with antioxidants in living donor liver transplantation donors

INTRODUCTION

Previous studies have demonstrated that oxidative stress by mediating the excessive production of reactive oxygen species is involved in tissue damage and organ failure during and after surgery. The impact of the preoperative immunonutrition including antioxidants on the postoperative course of patients undergoing hepatic surgery was investigated in this pilot study.

PATIENTS AND METHODS

Twenty-three living donor liver transplantation (LDLT) donors were randomly assigned to either an experimental (AO) group, received a commercial supplement enriched with antioxidant nutrients for each of the 5 days immediately prior to surgery while maintaining normal food intake, or a control (CT) group, administered no supplement. Antioxidative capacity was measured by spectrophotometry of patient serum using a free-radical analytical system.

RESULTS

The antioxidative capacity of 90.9% patients in the AO group increased after immunonutrition. Compared to the CT group, the AO group was found to have higher antioxidant capacity and transferrin levels; lower WBC, lymphocyte, and neutrophil counts; and briefer duration of postoperative fever during the postsurgical period. No significant differences were found between the 2 groups regarding the nutritional parameters; liver functioning parameters; immunological parameters; intraoperative factors; postoperative outcomes.

CONCLUSION

Preoperative immunonutrition including antioxidants might play a beneficial role in improving postsurgical immunological response but the modest biological advantage was not associated with any significant clinical outcome.

Repeat hepatectomy for intrahepatic recurrence of cholangiolocellular carcinoma

A 68-year-old man underwent a partial resection of the liver and lymph node dissection for a tumor, 3.0 cm in diameter, in S4 of the liver under the diagnosis of cholangiocellular carcinoma (CCC). The histological diagnosis was cholangiolocellular carcinoma (CoCC) and lymphatic permeation and venous invasion were recognized. Seven months after surgery, CT demonstrated two recurrent nodules in S7 and S8 of the liver, then a partial resection of the liver was performed. The gross and pathological findings were the same as the previously resected tumor. Four months after the second operation, CT demonstrated dilated intrahepatic bile ducts and lymph node swelling of the hepatic hilum. The patient died of disease thirteen months after the first operation. On the basis of the clinical and pathological features of this case, we consider that CoCC clinically resembles CCC and prognosis may be unfavorable, although it has characteristic pathological findings. It is still controversial whether CoCC should be accepted as a separate entity. The significance of repeat hepatectomy for recurrence and adjuvant chemotherapy should be clarified to improve the prognosis of CoCC.

Dendritic cell-based immunotherapy targeting synthesized peptides for advanced biliary tract cancer

BACKGROUND

The aim of this retrospective study was to clarify the safety and efficacy of dendritic cell (DC)-based immunotherapy targeting synthesized peptides, Wilms tumor 1 (WT1) and Mucin 1, cell surface associated (MUC1) for biliary tract cancers (BTCs).

METHODS

Sixty-five patients who had nonresectable, recurrent, or metastatic BTCs and received the DC-based immunotherapy were selected for the study. DCs were pulsed with WT1 and/or MUC1. The adverse events (AEs) and clinical responses were examined.

RESULTS

No serious treatment-related AEs were observed. Median survival time (MST) from diagnosis and from the first vaccination was 18.5 and 7.2 months, respectively. By multivariate Cox proportional hazard analysis, the significant independent factors were found to be (1) combined chemotherapy, (2) albumin level ≥4.0 g/dL before vaccination, (3) C-reactive protein level <0.5 mg/dL before vaccination, and (4) fever after vaccination. The MST from the first vaccination with or without chemotherapy was 8.2 and 5.3 months, respectively (P = 0.016), and MST for the patients with prognostic nutritional index ≥40 and <40 was 8.1 and 5.0 months, respectively (P = 0.023).

CONCLUSIONS

Although a small uncontrolled nonrandomized study, DC-based immunotherapy for BTCs was safe and produced a clinical response for the patients who underwent chemotherapy and maintained a good nutrition status.

Abstract 1759: Immunohistochemical detection of human telomerase reverse transcriptase in human cholangiocarcinoma and risk condition

Background/Aims: Telomerase activation plays a critical role in several human carcinogenesis through the maintenance of telomeres. The catalytic subunit of telomerase is human telomerase reverse transcriptase (hTERT), whose expression is the critical determinant of telomerase activity. Studies on hTERT in human cholangiocarcinoma (ChC) are rare, and there are no immunohistochemical studies on the correlations with its expressions and ChC patient's clinicopathological parameters.

Methods : HTERT Immunoreactivity was measured in cancerous parenchyma of 28 archival cases of human cholangiocarcinoma (ChC) compared with hyperplastic small biliary ducts in surrounding non-neoplastic liver. And hTERT immunoreactivity was also assessed in both large and small hyperplastic biliary ducts (HBDs) in 9 archival cases of primary sclerosing cholangitis (PSC), which is risk condition for human cholangiocarcinogenesis. Measurements of intrahepatic biliary duct sizes and quantitative microdensitometry measurements of immunostaining intensities were determined using a color video image analysis system. Micro-optical density values related to a standard optical density curve were generated for each set of measurements, using arbitrary units of immunostaining intensity ranging from 0 (nondetectable) to 255 (highest intensity).

Results : HTERT immunoreactivity was presented in nuclei of ChC and PSC cells. Mean micro-optical density values for hTERT in tumorous cells were almost 8-fold greater than that measured in small HBDs in surrounding non-tumorous liver within the same tissue sections. Although there was no significantly difference of tumor differentiation in hTERT expression, its expression was stronger in tubular type than in papillary type and in tubulopapillary type. In PSC cases, hTERT expression was significantly stronger in large HBDs (&gt;500μm cross-sectional diameter) than in small HBDs (&lt;500μm cross-sectional diameter).

Conclusion : Our findings suggest that hTRET protein in human ChC may emerge at a early stage in the progression of the malignant process. The results also suggest hTERT as potentially important targets relevant to chemoprevention or adjunct therapy of ChC.

Citation Format: Kanenori Endo, Shunichi Tsujitani, Miwa Yoshimoto, Jyoji Watanabe, Naruo Tokuyasu, Teruhisa Sakamoto, Takuji Naka, Yasuaki Hirooka, Masahide Ikeguchi. Immunohistochemical detection of human telomerase reverse transcriptase in human cholangiocarcinoma and risk condition. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1759. doi:10.1158/1538-7445.AM2013-1759

Abstract 2840: Dendritic cell-based immunotherapy targeting WT1 and MUC1 for advanced biliary tract cancer

Objectives:Despite intensive chemotherapy for biliary tract cancer (BTC), the outcome is not enough. Dendritic cells are the powerful antigen-presenting cells that have attracted attention from the efficacy of DC-based immunotherapy against many types of cancers. The objective of this study was to clarify the safety and efficacy of dendritic cell therapy for BTC.Methods: This retrospective study selected patients who underwent DC-based vaccine for BTC between May of 2009 and February of 2012. The safety of this treatment, median survival time (MST), 1-year survival rate, objective response rate (ORR), and disease control rate (DCR) were evaluated. The univariate and multivariate analyses were performed to identify the efficacy of DC by a Cox proportional hazards analysis.Results:Twenty-seven patients were selected for the study. The patients, and all but one patient had previous therapy, 13 patients had undergone prior surgical resection, and 21 patients went on to receive chemotherapy. No serious treatment-related adverse events were observed during the study period. One-year survival rate from 1st vaccination was 22 % and from the initial diagnosis was 67%. The MST from 1st vaccination and from the initial diagnosis were 8.2 months and 18.5 months, respectively. DCR and ORR were 37% and 11%,respectively. None of 27 patients showed complete response (CR), but we have found out 3 cases of partial responses (PR) and 7 cases of stable disease (SD).Furthermore, LDH, CRP, DTH, Performance Status (PS), combination with lymphokine-activated killer, chemotherapy were found to be statistically significant independent risk factors in multivariate analysis.Conclusion: DC-based immunotherapy for BTC was safe and prolonged the MST of the patients with BTC compared to chemotherapy alone,comparing the result from UK ABC-02 trial. DC-based immunotherapy for BTC may another option for BTC patient who has no chance for curative surgery.

Citation Format: Masanori Kobayashi, Tomoyo Sakabe, Mitsugu Tanii, Hirofumi Abe, Hedenori Takahashi, Shun-ichi Tsujitani, Shigetaka Shimodaira, Yoshikazu Yonemitsu, Masato Okamoto, Masaki Nagaya. Dendritic cell-based immunotherapy targeting WT1 and MUC1 for advanced biliary tract cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2840. doi:10.1158/1538-7445.AM2013-2840

Gastric cancer treated in 2002 in Japan: 2009 annual report of the JGCA nationwide registry

BACKGROUND

The Japanese Gastric Cancer Association (JGCA) started a new nationwide gastric cancer registration in 2008.

METHODS

From 208 participating hospitals, 53 items including surgical procedures, pathological diagnosis, and survival outcomes of 13,626 patients with primary gastric cancer treated in 2002 were collected retrospectively. Data were entered into the JGCA database according to the JGCA classification (13th edition) and UICC TNM classification (5th edition) using an electronic data collecting system. Finally, data of 13,002 patients who underwent laparotomy were analyzed.

RESULTS

The 5-year follow-up rate was 83.3 %. The direct death rate was 0.48 %. UICC 5-year survival rates (5YEARSs)/JGCA 5YEARSs were 92.2 %/92.3 % for stage IA, 85.3 %/84.7 % for stage IB, 72.1 %/70.0 % for stage II, 52.8 %/46.8 % for stage IIIA, 31.0 %/28.8 % for stage IIIB, and 14.9 %/15.3 % for stage IV, respectively. The proportion of patients more than 80 years old was 7.8 %, and their 5YEARS was 51.6 %. Postoperative outcome of the patients with primary gastric carcinoma in Japan have apparently improved in advanced cases and among the aged population when compared with the archival data. Further efforts to improve the follow-up rate are needed.

CONCLUSIONS

Postoperative outcome of the patients with primary gastric carcinoma in Japan have apparently improved in advanced cases and among the aged population when compared with the archival data. Further efforts to improve the follow-up rate are needed.

Impact of dendritic cell vaccines pulsed with Wilms' tumour-1 peptide antigen on the survival of patients with advanced non-small cell lung cancers

PURPOSE

Dendritic cell (DC)-based vaccines have been expected to serve as new therapeutic approaches for advanced non-small cell lung cancers (NSCLCs); however, their clinical outcomes have not been fully elucidated. We report a single-centre clinical study analysing factors affecting the survival of patients with advanced NSCLCs who received DC vaccines pulsed with or without Wilms' tumour protein-1 (WT1) peptide.

METHODS

Among 62 patients with previously treated inoperable or postoperatively relapsed NSCLCs who met the inclusion criteria, DCs from 47 (76%) patients who showed HLA-A2402/0201/0206 were pulsed with one or more corresponding WT1 peptide antigens. DC vaccines were intradermally injected biweekly.

RESULTS

Clinical responses based on response evaluation criteria in solid tumours (RECIST) were found in 31 (50%) patients at 3 months after the first DC vaccine (complete response: 1 (1.6%), partial response: 4 (6.5%), stable disease: 26 (41.9%)). Median survival time was 27 months (82% in 1 year and 54% in 2 years) from initial diagnosis, and that was 12 months (48% in 1 year and 22% in 2 years) from the first DC vaccination. Importantly, multivariate analyses revealed that only two factors, blood haemoglobin and the use of WT1 peptides, significantly affected the overall survival of patients from both initial diagnosis and first vaccination.

CONCLUSIONS

This study is the first to suggest that DC vaccines pulsed with WT1 may hold a significant impact to prolong the overall survival of patients with advanced NSCLCs.

Prognostic significance of KRAS and BRAF mutations in Japanese patients with colorectal cancer

e14033

Background: Recent evidence highlights the potential prognostic and predictive value of BRAF and K-RAS gene alterations in patients with colorectal cancer. To determine whether differences exist in the molecular mechanisms driving colorectal cancer between Japanese and Western, we characterized Japanese patients with colorectal cancer by assessing genetic alterations involved in cancer progression and response to treatment. Methods: We retrospectively evaluated 254 Japanese diagnosed with colorectal cancer at our institution between 1994 and 2009. Mutations in KRAS codons 12 and 13 and BRAF codon 600 were identified by direct sequencing. Microsatellite instability (MSI) status was determined by genotyping in the 5 loci. Associations between KRAS or BRAF mutation and clinicopathological characteristics and prognosis were evaluated. Results: KRAS and BRAF mutation were detected in 33.5% and 6.7% of all patients, respectively. KRAS mutation was correlated with poor recurrence free survival (RFS) (p = 0.03), especially in stage II patients (p = 0.007). BRAF mutation was significantly correlated with the anatomical site of tumor (p < 0.001), tumor grade (p = 0.001) and high frequency of microsatellite instability (p < 0.001). BRAF mutation was also correlated with poor overall survival in all cases of patients (p = 0.009). Overall, the background of KRAS and BRAF mutation was almost similar between CRCs of Western countries and those of Japanese. However, KRAS mutation status was considered to be helpful to predict recurrence in Japanese patients with stage II CRC. Conclusions: Our findings indicate that BRAF and K-RAS mutation plays an important role in the tumorigenesis of colorectal cancer. These results indicate that molecular analysis for BRAF and K-RAS may be a useful biomarker for identifying patients with right-sided colon cancer with poor outcome who may benefit from a more individualized course of therapy.

Significance of mortalin expression in gastric cancer with normal p53

25

Background: Gastric cancer still has the highest morbidity rate and the second highest mortality rate. As chemotherapy confers only a minimal survival advantage, the prognosis of patients with advanced or recurrent gastric cancer remains poor. Studying the mechanisms and underlying molecules that drives gastric cancer malignant, could contribute to finding a remedy for gastric cancer. Mortalin is a heat non-inducible member of the heat shock protein 70 family. Mortalin binds to p53 and prevents p53 from entering the nucleus, as well as cell stress. To understand the significance of mortalin in gastric cancer, we investigated the expression of mortalin and p53.

Methods: The expression of mortalin and p53 were examined by immunohistochemical staining of 182 clinical samples of gastric cancer.

Results: Mortalin-positive and aberrant-p53-positive samples were found in 75.2% and 62.6% of cases, respectively. Mortalin-positive tumors were deeper in invasion and had more lymph node and liver metastases compared with mortalin-negative tumors (p < 0.01, p < 0.05, respectively). Mortalin-positive tumors had worse prognosis compared with mortalin-negative tumors (p = 0.035). Moreover, in tumors with normal p53 expression, mortalin-positive tumors had especially worse prognosis compared with mortalin-negative tumors (p = 0.013). With multivariate analysis, mortalin expression appeared to be an independent prognostic factor in gastric cancer with expression of normal p53 (p = 0.0174).

Conclusions: Mortalin has a great impact on gastric cancer with normal p53. Therefore, mortalin is a target molecule for treatment of gastric cancer, as well as a promising prognostic factor, especially in tumors with normal p53.

Randomized controlled phase II study of alternate-day S-1 as adjuvant chemotherapy for gastric cancer

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Background: Based on the results of ACTS-GC, oral administration of S-1 for 1 year is considered standard postoperative adjuvant chemotherapy for gastric cancer in Japan. However, the 1-year treatment completion rate was only 65.8%, and completion of the treatment is a problem to be solved. On the other hand, we experienced in clinical practice that the alternate-day administration of S-1 reduced adverse effects and was tolerable for advanced gastric cancer patients unwilling to continue the standard daily administration. We therefore conducted a multi-center cooperative prospective study to compare daily with alternate-day administration of S-1 as postoperative adjuvant therapy for gastric cancer.

Methods: Patients with Stage II or III gastric cancer who underwent curative surgery were randomly assigned to receive standard daily administration (group A: S-1 80-120 mg/day according to BSA, days 1 to 28, every 6weeks, for 1 year) or alternate-day administration of S-1 (group B: S-1 80-120 mg/day according to BSA, every other day, for 15 months). The primary endpoints were treatment completion rate and relative dose intensity. Secondary endpoints were safety, overall survival, and relapse-free survival.

Results: A total of 73 patients were enrolled. As of August 30, 2011 analysis of the compliance data of 62 cases had been completed. The results showed a treatment completion rate of 74.2% in group A and 93.5% in group B and relative dose intensity of 72.1% in group A and 85.6% in group B, and compliance tended to be better in group B. Assessment of survival time showed a median follow-up time of 545 days, a 1-year survival rate of 93.8% in group A and 96.9% in group B and 1-year relapse-free survival rate of 79.5% in group A and 90.7% in group B. Digestive system adverse events were less frequent in group B than in group A.

Conclusions: We will report the data from the final analysis at this meeting. The current data show improved compliance and mitigation of adverse effects with alternate-day administration of S-1, and it appears to be a more sustainable option for adjuvant chemotherapy for Stage II and III gastric cancer.

Biological mechanism and clinical effect of protein-bound polysaccharide K (KRESTIN(®)): review of development and future perspectives

The mechanism of action of protein-bound polysaccharide K (PSK; KRESTIN(®)) involves the following actions: (1) recovery from immunosuppression induced by humoral factors such as transforming growth factor (TGF)-β or as a result of surgery and chemotherapy; (2) activation of antitumor immune responses including maturation of dendritic cells, correction of Th1/Th2 imbalance, and promotion of interleukin-15 production by monocytes; and (3) enhancement of the antitumor effect of chemotherapy by induction of apoptosis and inhibition of metastasis through direct actions on tumor cells. The clinical effectiveness of PSK has been demonstrated for various cancers. In patients with gastric or colorectal cancer, combined use of PSK with postoperative adjuvant chemotherapy prolongs survival, and this effect has been confirmed in multiple meta-analyses. For small-cell lung carcinoma, PSK in conjunction with chemotherapy prolongs the remission period. In addition, PSK has been shown to be effective against various other cancers, reduce the adverse effects of chemotherapy, and improve quality of life. Future studies should examine the effects of PSK under different host immune conditions and tumor properties, elucidate the mechanism of action exhibited in each situation, and identify biomarkers.

Relationship between expression of apoptosis-related proteins and the efficacy of postoperative chemotherapy in patients with T3 gastric cancer

PURPOSE

We investigated the relationship between the p53-dependent apoptotic pathway and the survival of patients with gastric cancer, retrospectively, to elucidate new biomarkers of uracil/tegafur (UFT) chemotherapy.

METHODS

We examined the expression of p53, p21, Bax, and myeloid cell leukemia 1 (Mcl-1) proteins immunohistochemically in 105 patients who underwent curative gastrectomy for gastric cancer invading the serosa. Postoperative oral UFT was prescribed for 1 year. Kaplan-Meier survival curves were compared with the two-sided log-rank test.

RESULTS

Positive staining for p53, p21, Bax, and Mcl-1 proteins was found in 63.8, 52.4, 39.0, and 72.4% of the subjects, respectively. Survival time did not differ significantly between the patients with and those without p53, p21, and Bax expression. However, patients with Mcl-1- tumors survived longer than those with Mcl-1+ tumors. Postoperative UFT treatment did not improve survival; however, adjuvant UFT significantly prolonged the survival of patients with p53-, p21-), Bax+, or Mcl-1+ tumors, but not of patients with p53+, p21+, Bax-, or Mcl-1- tumors.

CONCLUSIONS

The efficacy of adjuvant chemotherapy for gastric cancer may be affected by the status of apoptosis-related proteins such as p53, p21, Bax, and Mcl-1. However, because susceptibility to apoptosis did not explain the sensitivity of chemotherapeutic agents, further investigation of the mutual interaction between apoptosis-related proteins is required.

Cytokine-based high log-scale expansion of functional human dendritic cells from cord-blood CD34-positive cells

Dendritic cells (DCs) play a crucial role in maintaining the immune system. Though DC-based cancer immunotherapy has been suggested as a potential treatment for various kinds of malignancies, its clinical efficacies are still insufficient in many human trials. Issues that limit the clinical efficacy of DC-based immunotherapy, as well as the difficulty of the industrial production of DCs, are largely due to the limited number of autologous DCs available from each patient. We here established a possible breakthrough, a simple cytokine-based culture method to expand the log-scale order of functional human DCs. Floating cultivation of cord-blood CD34(+) cells under an optimized cytokine cocktail led these progenitor cells to stable log-scale proliferation and to DC differentiation. The expanded DCs had typical features of conventional myeloid DCs in vitro. Therefore, the concept of DC expansion should contribute significantly to the progress of DC immunotherapy.

Secondary resistance of extra-gastrointestinal stromal tumors to imatinib mesylate: report of a case

Extra-gastrointestinal stromal tumors (EGISTs) that do not originate in the digestive tract are rare. We report a case of multiple EGISTs, which was monitored closely by KIT gene mutation analysis and other investigations. The patient was a 52-year-old man in whom multiple tumors in the abdominal cavity were diagnosed as EGISTs. Immunohistochemical analysis revealed positive staining for c-kit; however, no mutations were found in the KIT gene. The tumors decreased in size remarkably following treatment with imatinib mesylate, but after 2 years of this treatment, multiple liver metastases and some regrowth of the abdominal masses were found simultaneously. The liver metastasis and the abdominal masses were excised, and further analysis of the KIT gene revealed the same mutation in exon 11 in the KIT gene in the metastatic tumors. We speculate that the treatment might have triggered development of the imatinib mesylate-resistant clone, which may have existed in the primary lesion as a KIT gene mutant. This report provides valuable insight into the mechanisms of recurrent GISTs after treatment with imatinib mesylate.

Assessment of predictors of mortality and severity in patients with colorectal perforation

Colorectal perforation is a life-threatening disease with high mortality and morbidity. The correct and prompt diagnosis and accurate judgment of severity are necessary. We retrospectively investigated 30 patients with colorectal perforation to assess predictors of mortality and severity, and evaluated the usefulness of computed tomography (CT) for the initial diagnosis. The severity of peritonitis was assessed using clinical factors and Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity (POSSUM) scores. Abdominal free air was detected by CT in 92% of patients with colorectal perforation, whereas only 36.6% showed evidence of abdominal free air by conventional radiography. The perforation site was correctly diagnosed in 14 of 25 cases (56%). Overall mortality was 16.7%. Survivors were younger than nonsurvivors, and POSSUM physiological and mortality scores were significantly lower for survivors compared with nonsurvivors. The amount of intraperitoneal soiling by large bowel content determined disease severity in terms of the need for postoperative respiratory management. In conclusion, CT is necessary for precise diagnosis, and the POSSUM score is helpful for the evaluation of disease mortality and severity.

Antagonism of VEGF by genetically engineered dendritic cells is essential to induce antitumor immunity against malignant ascites

Malignant ascitis (MA) is a highly intractable and immunotherapy-resistant state of advanced gastrointestinal and ovarian cancers. Using a murine model of MA with CT26 colon cancer cells, we here determined that the imbalance between the VEGF-A/vascular permeability factor and its decoy receptor, soluble fms-like tryrosine kinase receptor-1 (sFLT-1), was a major cause of MA resistance to dendritic cell (DC)-based immunotherapy. We found that the ratio of VEGF-A/sFLT-1 was increased not only in murine but also in human MA, and F-gene-deleted recombinant Sendai virus (rSeV/dF)-mediated secretion of human sFLT-1 by DCs augmented not only the activity of DCs themselves, but also dramatically improved the survival of tumor-bearing animals associated with enhanced CTL activity and its infiltration to peritoneal tumors. These findings were not seen in immunodeficient mice, indicating that a VEGF-A/sFLT-1 imbalance is critical for determining the antitumor immune response by DC-vaccination therapy against MA.

Prognostic indicators in node-negative advanced gastric cancer patients

BACKGROUND AND OBJECTIVES

Despite carrying better overall prognoses, some node-negative gastric cancer patients die from recurrent malignancies. Identifying factors associated with disease-specific survival in adequately staged node-negative gastric cancer is important, as these patients are presumably free of microscopic regional metastases and may derive significant benefit from existing or future adjuvant strategies.

METHODS

To investigate significant prognostic indicators in node-negative advanced gastric cancer patients, we reviewed 777 advanced gastric cancer patients who had undergone curative gastrectomies.

RESULTS

The 5-year survival rate of node-negative advanced gastric cancer patients is 84.9%, which is significantly better than that of patients with lymph node metastasis. Multivariate analysis indicated that tumor size, histology, and depth of invasion are independent prognostic factors. The 5-year survival rate of patients with larger tumors (>or=7 cm), poorly differentiated adenocarcinoma, and serosal invasion was 49.1%, which was significantly worse that of patients with fewer or none of these factors.

CONCLUSIONS

Tumor size, histology, and the presence of serosal invasion are strong indicators of poor prognosis in node-negative advanced gastric cancer patients.

Abstract 185: Protein expression of DNMT1, DNMT3a, and DNMT3b in human hepatocellular carcinoma

Background/Aims: DNA methylation plays an important roles in the regulation of gene expression. Gene silencing by aberrant hypermethylation of CpG islands in gene promoter regions in frequently found in human cancers. By the assistance of DNA methyltransferases (DNMTs), methyl groups are transferred to promoter CpG islands, many tumor suppressor gene can be silenced by promoter CpG islands methylation. However, studies on DNMTs in hepatocellular carcinoma (HCC) are rare, and there are no immunohistochemical studies on the correlations with these expressions and HCC patient's suvival.

Methods : We immunohistochemically examined the expression of DNMT1, DNMT3a and DNMT3b and the relationships between these expressions and histological grade, clinicopathological parameters and patient's survival in 95 patients with HCC.

Results : DNMT1, DNMT3a and DNMT3b immunoreactivities were presented in nuclei of HCC cells. In the tumorous lesion, the number of positive immunoreactivities was 95/95 (100%) for DNMT1, 87/95 (92%) for DNMT3a and 81/95 (85%) for DNMT3b. The degree of each protein expression significantly correlated with tumor differentiation and intrahepatic metastasis, and only DNMT3a protein expression significantly correlated with portal vein imvolvement of tumor. Though there were no relations between the DNMTs expression and tumor size, over-expressions of DNMT3a and 3b proteins were associated with poor prognosis of HCC's patients. Moreover, the overall survival rate of patients group that showed over-expression of three DNMTs in tumorous lesion was significantly lower than it of other patients groups.

Conclusion : DNMTs are involved in HCC progression, and their overexpression is associated with poor prognosis.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 185.

Recent results of therapy for scirrhous gastric cancer

The prognosis of patients with scirrhous gastric cancer (SGC) is extremely poor. However, recent advances in therapeutic strategies against SGC, using effective anticancer drugs, have prolonged the survival of patients with SGC. This paper reviews the recent therapeutic outcomes of this type of gastric cancer and introduces a new treatment protocol for SGC.

Prognostic significance of the ratio between metastatic and dissected lymph nodes (n ratio) in patients with advanced gastric cancer

BACKGROUND AND OBJECTIVES

To determine the prognostic significance of the ratio between metastatic and dissected lymph nodes (n ratio) in gastric cancer patients.

METHODS

We retrospectively reviewed 777 advanced gastric cancer patients who had undergone curative gastrectomy at our hospital.

RESULTS

The n ratio was significantly greater in cases with a large tumor, undifferentiated tumor, lymphatic vessel invasion, or blood vessel invasion. Furthermore, the n ratio was significantly correlated with the depth of invasion, level of lymph node metastasis, and number of lymph node metastases. The prognosis for gastric cancer patients correlated well with the n ratio. Multivariate analysis indicated that the n ratio, but not the number of lymph node metastases, was an independent prognostic indicator. Moreover, the n ratio was an independent prognostic factor in N1, N2, and N3 patients defined by the Japanese Classification of Gastric Cancer (JCGC).

CONCLUSIONS

The n ratio is useful for evaluating the status of lymph node metastasis in gastric cancer. Therefore, the addition of the n ratio to the N (nodal) category defined by the JCGC may be a useful strategy in the N-staging classification of gastric cancer.

Elevated Fas expression is related to increased apoptosis of circulating CD8+ T cell in patients with gastric cancer

BACKGROUND

Extensive apoptosis of immune cells occurs in patients with cancer, and is possibly related to immune evasion by cancer cells. The present study was designed to investigate the correlation between apoptosis levels and Fas expression in CD8+ T lymphocytes in patients with gastric cancer.

METHODS

The expression of apoptosis markers (annexin V binding and caspase-3 activation) and the death receptor Fas in CD8+ T cells was evaluated by multicolor flow cytometry. Soluble Fas ligand (sFasL) in the sera was quantitated by enzyme-linked immunosorbent assay.

RESULTS

In patients with gastric cancer, 18.7% +/- 10.5% (mean +/- SD) of CD8+ T cells bound annexin V compared with 11.7% +/- 7.9% in normal controls (P = 0.0282). Fas expression in CD8+ T cells was higher in patients with gastric cancer (69.2% +/- 15.3%) than normal controls (50.6% +/- 15.3%) (P = 0.0051). The proportion of apoptotic CD8+ T cells was significantly correlated with Fas expression in CD8+ T cells (r = 0.409, P = 0.0214). In patients, Fas+CD8+ T cells preferentially underwent apoptosis and showed high caspase-3 activation. Moreover, the proportion of apoptotic CD8+ T cells was inversely correlated with serum levels of soluble Fas ligand (r = -0.324, P = 0.0359). Fas expression in tumor infiltrating CD8+ T cells was significantly more frequent (80.3% +/- 13.4%) than in circulating CD8+ T cells (67.9% +/- 15.5%) (P = 0.0046). A decrease in the percentage of Fas+CD8+ T cells was observed after surgery (54.1% +/- 12.8%) compared with before surgery (65.9% +/- 17.0%) (P = 0.0284).

CONCLUSIONS

The data indicate that up-regulation of Fas expression in CD8+ T cells is related to increased apoptosis of circulating CD8+ T cells in patients with gastric cancer. Further investigations into the detailed mechanism of apoptosis induction in Fas-positive CD8+ T cells are urgently required.

Clinical significance of skip metastasis in patients with gastric cancer

BACKGROUND

Metastasis appearing to bypass or skip tiers of lymph nodes (LNs) has been referred to as skip metastasis. The clinical impact of skip metastasis in gastric cancer remains unclear.

METHODS

In patients with gastric cancer, the clinicopathological features and postoperative prognoses of 21 patients with skip metastasis were evaluated and compared with findings in patients with group 1 (N1) or group 2 (N2) LN metastasis.

RESULTS

Of the 21 patients with skip metastasis, 9 patients had metastasis in the LN along the common hepatic artery (No. 8a), 8 patients had metastasis in the LN along the left gastric artery (No. 7), 2 patients had metastasis in LNs No. 7 and No. 8a, 1 patient had metastasis in the LN at the splenic hilum (No. 10), and 1 patient had metastasis in LN No. 10 and the LN along the splenic artery (No. 11). The mean diameter of the tumors in the patients with skip metastasis was 5.7 +/- 2.4 cm, which was significantly smaller than those in the N1 patients (7.9 +/- 4.1 cm) and N2 patients (9.3 +/- 4.6 cm). The incidence of serosal invasion, lymphatic vessel invasion, and peritoneal metastasis was lower in patients with skip metastasis compared with N2 patients. The 5-year survival rates were 70.2%, 62.0%, and 31.2% in patients with skip metastasis, patients with metastasis in group 1 LNs, and those with metastasis in group 2 LNs, respectively. The prognosis of patients with metastasis in group 2 LNs was significantly worse than that of patients with either skip metastasis (P = 0.0029) or metastasis in group 1 LNs (P < 0.0001).

CONCLUSION

Our data indicate that both the clinicopathological characteristics and the prognoses of patients with skip metastasis were similar to those of patients with N1 LN metastasis, but these features were not similar to those in patients with N2 LN metastasis. The sites of skip metastasis presented in the current study may be the key for applying the concept of the sentinel node in gastric cancer.

Prognostic significance of receptor-binding cancer antigen expressed on SiSo cells (RCAS1) expression in relation to cadherin expression in patients with colorectal carcinoma

PURPOSE

This study was designed to assess the prognostic value of receptor-binding cancer antigen expressed on SiSo cells expression and its relationship with cadherin expression in patients with colorectal cancer.

METHODS

The expressions of receptor-binding cancer antigen expressed on SiSo cells and E-cadherin were analyzed with special reference to prognosis in 105 patients with colorectal cancer.

RESULTS

Receptor-binding cancer antigen expressed on SiSo cells immunoreactivity was detected in the membrane and cytoplasm of tumor cells and considered to be positive in 48 patients (45.7 percent). The expression of receptor-binding cancer antigen expressed on SiSo cells was significantly correlated with lymph node metastasis (P = 0.0004), venous invasion (P = 0.0062), Dukes stages (P < 0.0001), and serum levels of carcinoembryonic antigen (P = 0.014). Furthermore, receptor-binding cancer antigen expressed on SiSo cells expression was significantly correlated with a poor prognosis (P < 0.001), and multivariate analysis indicated that it was an independent prognostic indicator. The expression of receptor-binding cancer antigen expressed on SiSo cells was more frequently found in tumors with reduced or abnormal expression of E-cadherin. The survival time of patients with reduced/abnormal E-cadherin expression was significantly shorter than that of patients with normal E-cadherin expression among patients with receptor-binding cancer antigen expressed on SiSo cells expression (P = 0.0043) but did not differ for those without receptor-binding cancer antigen expressed on SiSo cells expression (P = 0.17). Furthermore, multivariate analysis revealed that reduced/abnormal expression of E-cadherin was an independent prognostic factor in patients with receptor-binding cancer antigen expressed on SiSo cells expression but not in those without receptor-binding cancer antigen expressed on SiSo cells expression.

CONCLUSIONS

Receptor-binding cancer antigen expressed on SiSo cells expression is significantly correlated with tumor progression and poor prognosis in patients with colorectal cancer. Both reduced E-cadherin and enhanced receptor-binding cancer antigen expressed on SiSo cells expression may be critical for the mechanism of metastasis and recurrence in human colorectal cancer.

Expression of phosphorylated Akt (pAkt) in gastric carcinoma predicts prognosis and efficacy of chemotherapy

BACKGROUND

The Akt signaling pathway controls the survival and growth of human cancers. We investigated the expression of phosphorylated Akt (pAkt) in patients with gastric cancer.

METHODS

The expression of pAkt was immunohistochemically examined in 140 gastric cancer patients who underwent a gastrectomy. The expression of pAkt was evaluated based on staining intensity, and staining was classified as negative or positive. We examined the expression of pAkt and its association with the clinicopathological findings, prognosis, depth of invasion, the expression of p53, and efficacy of oral fluorouracil chemotherapy after surgery.

RESULTS

Expression of pAkt was positive in 81 (58%) patients and negative in 59 (42%) patients. There were no significant correlations between pAkt expression and the clinicopathological findings. The prognosis of patients with pAkt-negative tumors was superior to that of patients with pAkt-positive tumors, and the difference was significant for T3/T4 gastric cancer (P < 0.05). Among the patients with T3/T4 gastric cancer, postoperative oral fluorouracil treatment was effective in those who were pAkt-positive. Multivariate analysis revealed that pAkt expression and lymph node metastasis were independent prognostic factors. In 88 patients with T3 gastric carcinoma who had undergone curative surgery, in whom we studied the prognostic impact of a combined analysis of pAkt and p53 expression, patients with both pAkt- and p53-positive tumors showed a significantly poorer prognosis than patients with either or both pAkt- and p53-negative tumors (P < 0.05).

CONCLUSION

Our results indicate that pAkt expression may be useful for predicting the prognosis and efficacy of fluorouracil treatment in patients with gastric cancer.

Recurrence in early gastric cancer--presence of micrometastasis in lymph node of node negative early gastric cancer patient with recurrence

BACKGROUND/AIMS

There are cases of recurrence even after curative resection in early gastric cancer.

METHODOLOGY

Seven hundred and sixty-five patients with early gastric cancer who underwent curative gastrectomy were analyzed to identify the prognostic factor. Micrometastases within lymph nodes were determined by immunohistochemistry using anti-cytokeratin antibody in node-negative early gastric cancer patients with recurrence.

RESULTS

The recurrence was observed in 17 patients. Hematogenous recurrence was observed most frequently (47.1%), followed by peritoneal recurrence (23.5%). Of 17 patients with recurrence, 6 (35.3%) patients died more than 5 years after operation. The prognosis was poorer when the patients were older, and the depth of invasion was greater, lymph node metastasis, lymphatic involvement, and vascular involvement were present, and lymph node dissection was limited. The independent prognostic factors were lymph node metastasis, lymph node dissection, and age by multivariate analysis using Cox proportional hazards. Micrometastases within lymph nodes were confirmed in 3 of 6 node-negative patients with recurrence.

CONCLUSIONS

When patients have lymph node metastases or are older, close and long-term follow-up and careful planning of postoperative adjuvant therapy might be necessary to avoid recurrence. The detection of micrometastases by anti-cytokeratin antibody might be useful for predicting the possibility of recurrence in early gastric cancer.

Prediction of sites of recurrence in gastric carcinoma using immunohistochemical parameters

BACKGROUND AND OBJECTIVES

To improve prognosis of patients with gastric cancer, it is important to detect recurrences at an early stage following surgery. If the site of recurrence can be predicted, recurrent disease can be easier detected at an early stage. However, this is difficult to achieve using normal clinicopathological factors. We aimed to predict sites of recurrence in patients with advanced gastric carcinoma who underwent curative resection.

METHODS

Expressions of vascular endothelial growth factor (VEGF), transforming growth factor (TGF)-ss1, and p53, together with density of microvessels (MVs), and dendritic cell (DC) infiltration were examined by immunohistochemistry to evaluate their relationships with recurrence patterns in patients with advanced gastric carcinoma (n = 92).

RESULTS

All immunohistochemical parameters closely correlated with prognosis (TGF-ss1, P = 0.008; VEGF, P < 0.001; p53, P = 0.028; MV, P < 0.001; DC, P < 0.001). Multivariate analysis showed that DC infiltration (P = 0.02; HR, 2.52; 95%CI, 1.16-5.48), MV density (P = 0.023; HR, 2.48; 95%CI, 1.13-5.44), VEGF expression (P = 0.002; HR, 3.27; 95%CI, 1.52-7.05), and lymph node metastasis (P < 0.0001; HR, 2.09; 95%CI, 1.49-2.93) were independent prognostic factors. A multivariate logistic regression analysis indicated that DC infiltration (P = 0.004; Odds ratio, 4.25; 95%CI, 1.51-11.96) and lymph node metastasis (P = 0.01; Odds ratio, 3.37; 95%CI, 1.31-8.66) provided significant estimates of relative risks for development of peritoneal recurrence. Upon development of hematogenous recurrence, VEGF expression significantly indicated relative risks (P < 0.001; Odds ratio, 7.26; 95%CI, 1.41-37.3). Moreover, p53 expression closely correlated with lymph node recurrence (P = 0.042; Odds ratio, 11; 95%CI, 1.26-95.7).

CONCLUSIONS

Assessment of immunohistochemical parameters can predict sites of recurrence in gastric carcinomas, and thus contributes to improve prognosis.

Prognostic significance of RCAS1 expression in relation to the infiltration of dendritic cells and lymphocytes in patients with esophageal carcinoma

RCAS1 (receptor-binding cancer antigen expressed on SiSo cells) expression was determined in 107 esophageal carcinoma patients by immunohistochemical procedures and compared with tumor infiltrating lymphocyte (TIL) and dendritic cell (DC) infiltration to evaluate the effect of RCAS1 on immune responses in esophageal carcinoma. RCAS1 immunoreactivity was detected in 59 of 107 patients (55.1%). RCAS1 expression was significantly correlated with the depth of invasion, lymph node metastasis, and histologic stage. RCAS1 expression tended to be correlated with a lower TIL density in tumors with marked DC infiltration. The survival time for patients with RCAS1-negative tumors was significantly longer than that for patients with RCAS1-positive tumors. Especially, the prognosis was predicted by RCAS1 in cases with marked DC infiltration. Multivariate analysis revealed that RCAS1 expression was an independent prognostic factor. RCAS1 expression may play an important role in evading the immunological defense mechanisms in esophageal carcinoma.

Prognostic significance of level and number of lymph node metastases in patients with gastric cancer

BACKGROUND

To present data that provide some insight into the appropriateness of a nodal grouping category and its relation to survival in patients with gastric cancer.

METHODS

We reviewed data of 777 patients with advanced gastric cancer who had undergone curative gastrectomy to investigate the prognostic significance of level and number of lymph node metastases.

RESULTS

The prognosis of patients with gastric cancer was well correlated with the level and number of lymph node metastases. Multivariate analysis indicated that the level and number of lymph node metastases were independent prognostic indicators. Moreover, the number of lymph node metastases was an independent prognostic factor in N1, N2, and N3 patients. The most statistically significant difference in disease-specific survival was observed at a threshold of 11 lymph node metastases, yielding a chi2 value of 42.88, a hazard ratio of 2.523, at a 95% confidence interval of 1.913, 3.329 (P < .0001) by Cox proportional hazard model. On the basis of this result, patients were divided into two groups as follows: marked lymph node metastasis group (number of positive nodes > or =11) and slight lymph node metastasis group (number of positive nodes < or =10). The prognosis of patients with marked lymph node metastasis was statistically significantly worse than that with slight lymph node metastasis in N1, N2, and N3 patients.

CONCLUSIONS

Both level and number were indispensable for evaluating lymph node metastasis. Therefore, addition of the number of positive nodes to the N category defined by the Japanese Classification of Gastric Carcinoma may be a useful strategy in the N staging classification in gastric cancer.

Decreased NKG2D expression on CD8+ T cell is involved in immune evasion in patients with gastric cancer

PURPOSE

Some studies suggest that the immunoreceptor NKG2D expression on CD8(+) T cells is down-regulated and this reduction may be involved in immune evasion in cancer patients. The present study was designed to investigate NKG2D expression on CD8(+) T lymphocytes and its relationship to immune evasion in gastric cancer patients.

EXPERIMENTAL DESIGN

NKG2D expression on both circulating and tumor-infiltrating CD8(+) T cells was evaluated by multicolor flow cytometry. Soluble MHC class I chain-related gene A (MICA) in the sera was quantitated by ELISA. Transwell experiments were carried out to determine the effect of cancer cells on NKG2D expression.

RESULTS

NKG2D expression on circulating CD8(+) T cells was down-regulated and significantly correlated with IFN-gamma production in gastric cancer patients (r = 0.68; P = 0.007). NKG2D expression was closely related to undifferentiated cancer (P = 0.021) as was the depth of invasion (P = 0.012). There was no difference in soluble MICA between gastric cancer patients and normal controls. NKG2D expression on CD8(+) T cells was remarkably reduced in the tissue of gastric cancer compared with peripheral blood (P = 0.046). Complete removal of tumor by surgery restored NKG2D expression on CD8(+) T cells (P = 0.0049). Transwell experiments showed that this down-regulation was induced by direct contact between cancer cells and CD8(+) T cells and that soluble factors did not affect the NKG2D expression. This phenomenon was blocked by the addition of anti-MICA antibodies.

CONCLUSIONS

Decreased NKG2D expression may be one of the key mechanisms responsible for immune evasion by tumors in gastric cancer.

Distinct recurrence pattern and outcome of adenocarcinoma of the gastric cardia in comparison with carcinoma of other regions of the stomach

BACKGROUND

Carcinoma arising in the cardioesophageal junction is a distinct clinical entity compared with tumors located in other regions of the stomach. The prognosis for adenocarcinoma of the upper stomach is considered to be relatively poorer than carcinomas of the more distal stomach. We have therefore investigated patients with carcinoma of the gastric cardia in order to evaluate the underlying cause of this poor prognosis.

MATERIALS AND METHODS

Clinicopathologic features and postoperative prognosis of 101 patients with carcinoma of the cardia were evaluated and compared with findings on 1884 patients with tumors in other regions of the stomach.

RESULTS

Tumors of the cardia had a mean size of 6.8 cm, which was significantly larger than the mean size of 5.9 cm for tumors found in the middle- and lower third of the stomach. The incidence of serosal invasion, lymph node metastasis, and lymphatic and blood vessel invasion was higher in association with adenocarcinoma of the cardia than with adenocarcinoma in remaining parts of the stomach. In the analysis of patients who had undergone curative resection, the 5-year survival rates were 61.6, 79.1, and 82.6% in patients with carcinoma of the cardia, upper one-third, and remaining middle- and lower one-third of the stomach, respectively, and the differences were statistically significant. Multivariate analysis indicated that adenocarcinoma of the gastric cardia is an independent prognostic factor. With regard to the site of recurrence, both lymph node and hematogenous recurrence were observed more frequently in the cardia than in the remaining parts of the stomach.

CONCLUSIONS

Our data indicate that the prognosis of patients with adenocarcinoma of the gastric cardia is extremely poor. To improve their prognosis, new treatments in addition to gastrectomy with extensive lymph node dissection are needed.

Effect of age on prognosis in patients with gastric cancer

BACKGROUND

The incidence of gastric cancer among the elderly has recently been increasing; however, the prognostic value of age in patients with gastric cancer remains elusive.

METHODS

A total of 1473 patients with gastric cancer, who had undergone curative gastrectomy were reviewed to investigate the prognostic significance of age.

RESULTS

Blood vessel invasion and differentiated type were more frequently observed in elderly than nonelderly patients (P < 0.0001) and elderly patients underwent limited lymph node dissection compared with nonelderly patients (P < 0.001). Moreover, chemotherapy was carried out in nonelderly patients more frequently than in elderly patients (P < 0.005). Ten-year survival rates were 70.2 and 81.4% in elderly and nonelderly patients, respectively, and the differences were statistically significant (P < 0.001). Postoperative mortality rates were 3.2 and 2.0% in elderly and nonelderly patients, respectively. Hematogenous recurrence was more frequently observed in elderly patients than nonelderly patients (P < 0.05). Multivariate analysis showed that age was an independent prognostic factor.

CONCLUSIONS

Age clinically serves as a simple predictor of survival in patients with gastric cancer and should be taken into account along with conventional clinicopathological variables such as depth of invasion and lymph node metastasis.

Macroscopic tumor size as a simple prognostic indicator in patients with gastric cancer

BACKGROUND

In some cancers, such as breast and lung, tumor size is included in the classification of disease stage. However, it's clinical significance remains elusive in gastric cancer.

METHODS

To investigate the prognostic significance of macroscopic tumor size, we reviewed 1473 gastric cancer patients who underwent curative gastrectomy.

RESULTS

An appropriate threshold of tumor size affecting patient survival was 8 cm. Patients were divided into 2 groups as follows: small size group (SSG=tumor size<8 cm) and large size group (LSG=tumor size>or=8 cm). LSG tumors were frequently observed in patients with undifferentiated types and with lymphatic and venous invasion. Moreover, tumor size was significantly related to depth of invasion and lymph node metastasis. The prognosis of LSG patients was significantly worse than that of SSG patients. Multivariate analysis showed that tumor size was an independent prognostic factor along with depth of invasion, lymph node metastasis, and lymphatic invasion. Recurrence patterns differed between the 2 groups. Peritoneal recurrence was observed in LSG more frequently than SSG patients (P<.001), whereas hematogenous recurrence was observed in SSG more frequently than in LSG patients (P<.05). The survival rates of patient with stages II-, IIIa-, and IIIb-LSG disease were almost the same as those with stages IIIa-, IIIb-, and IV-SSG disease, respectively.

COMMENTS

Tumor size serves as a simple predictor of survival in patients with gastric cancer.

Expression of polo-like kinase 1 (PLK1) protein predicts the survival of patients with gastric carcinoma

OBJECTIVE

To assess the prognostic value of polo-like kinase 1 (PLK1), an important regulator of cell cycle progression, in patients with gastric carcinoma.

METHODS

PLK1 expression was determined in 160 gastric carcinoma patients by immunohistochemistry and compared with p53 expression and the proliferating cell nuclear antigen-labeling index (PCNA-LI) to evaluate the effect of PLK1 on tumor progression. Furthermore, PLK mRNA expression was determined in 26 advanced gastric cancer patients by reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS

PLK mRNA expression was detected in 25 (96.2%) patients by RT-PCR. Immunohistochemical staining revealed PLK1 expression in 84 (52.5%) patients. There were no significant relationships between PLK1 expression and various clinicopathological factors. PLK1 expression was significantly correlated with the PCNA-LI, but not p53 expression. The prognosis of patients with PLK1-positive tumors was significantly worse than that of patients with PLK1-negative tumors (p < 0.05). Moreover, multivariate analysis revealed that PLK1 expression was an independent prognostic factor. Patients with PLK1-positive and high PCNA-LI tumors showed a significantly poorer prognosis than patients with PLK1-negative and/or low PCNA-LI tumors. Furthermore, the prognosis of patients with PLK1- and p53-positive tumors was significantly worse than that of patients with PLK1- and p53-negative or PLK1-negative and p53-positive tumors.

CONCLUSION

PLK1 expression may be a critical indicator of a poor prognosis in patients with gastric carcinoma.

Allogeneic gastric cancer cell-dendritic cell hybrids induce tumor antigen (carcinoembryonic antigen) specific CD8(+) T cells

The development of protocols for the ex vivo generation of dendritic cells (DCs) has led to intensive research of their potential use in immunotherapy. Accumulating results show the efficacy of this treatment on melanomas which are highly immunogenic. However, its efficacy remains unclear in other tumors. In this study, allogeneic gastric cancer cell-DC hybrids were used to determine the efficacy of this type of immunotherapy in gastric cancer. Fusion cells of DC and allogeneic gastric cancer cells were generated by polyethylene glycol (PEG) and electrofusion. These hybrids were used to induce tumor associated antigen (TAA) specific cytotoxic T lymphocytes (CTLs). The DCs were successfully fused with the allogeneic gastric cancer cells resulting in hybrid cells. These hybrid cells were functional as antigen-presenting cell because they induced allogeneic CD4(+) T cells proliferation. CD8(+) T cells stimulated by the MKN-45-DC hybrid cells were able to kill MKN-45 when used for immunization. The CTLs killed another gastric cancer cell line, MKN-1, as well as a melanoma cell line, 888mel, suggesting the recognition of a shared tumor antigen. MKN-45 specific CTLs can recognize carcinoembryonic antigen (CEA), indicating that the killing is due to tumor antigens as well as alloantigens. This approach suggests the possible use of allogeneic gastric cancer cell-DC hybrids in DC based immunotherapy for gastric cancer treatment.

Interleukin-10 expression significantly correlates with minor CD8+T-cell infiltration and high microvessel density in patients with gastric cancer

We aimed to investigate the relationships between interleukin-10 (IL-10) expression and both the clinicopathological findings and prognoses in patients with gastric cancer and to compare IL-10 expression with microvessel (MV) density and CD8+ T lymphocyte infiltration to evaluate its effects on angiogenesis and immune responses in gastric cancer. IL-10 expression was determined in gastric cancer patients by reverse transcription-polymerase chain reaction (RT-PCR) or immunohistochemical procedures. Two of 7 normal gastric tissues showed IL-10 mRNA expression, while its expressions were confirmed in all advanced gastric carcinoma tissues examined (n=11) by RT-PCR. Immunohistochemical staining demonstrated that IL-10 expression was detected in 52 (47.7%) of 109 cases. There was a close correlation between IL-10 expression and MV density. IL-10 expression inversely correlated with CD8+ T-lymphocyte infiltration. The prognoses of patients whose tumors expressed IL-10 were significantly worse than those of patients whose tumors did not express IL-10. Multivariate analysis indicated IL-10 expression was an independent prognostic factor. IL-10 might be associated with tumor progression by stimulating angiogenesis and suppressing immune responses in gastric cancer.

Expression of inducible nitric oxide synthase is significantly correlated with expression of vascular endothelial growth factor and dendritic cell infiltration in patients with advanced gastric carcinoma

OBJECTIVE

Nitric oxide (NO) is a product of L-arginine to L-citrulline conversion by nitric oxide synthase (NOS). The inducible form of NOS (iNOS) is one of three classes of NOS and the strongest producer of NO. It has been reported that NO correlates with angiogenesis and immune responses in some types of cancer, however, the correlations between iNOS expression, angiogenesis, and immune responses are still unclear in gastric carcinoma.

METHODS

iNOS expression was determined in 135 gastric cancer patients by immunohistochemical procedures and compared with the expression of vascular endothelial growth factor (VEGF), microvessel (MV) density, and dendritic cell (DC) infiltration to evaluate the effect of iNOS on angiogenesis and immune responses in gastric carcinoma.

RESULTS

iNOS expression was detected in 106 (78.5%) of 135 cases. There was a close correlation between iNOS expression and VEGF expression, a correlation with MV density and an inverse correlation with DC infiltration. There was no correlation between iNOS and p53 expression. The prognoses of patients whose tumors expressed iNOS were significantly worse than those of patients whose tumors did not express iNOS. Multivariate analysis indicated iNOS expression was an independent prognostic factor.

CONCLUSION

iNOS might be associated with tumor progression by stimulating angiogenesis and suppressing immune responses in gastric carcinoma.

Laparoscopic-Assisted Intraperitoneal Chemotherapy for Patients with Scirrhous Gastric Cancer

BACKGROUND

The prognosis for patients with scirrhous gastric cancer (SGC) is extremely poor. To improve the patients' prognosis, laparoscopic-assisted intraperitoneal chemotherapy (IPC) was introduced for SGC. In this study, we analyzed whether IPC reduced the number of cancer cells in the peritoneal cavity of patients or changed the gene expression levels of cytokines in the peritoneal cavity. We also investigated whether IPC improved the prognosis of patients with SGC.

METHODS

Total RNA was extracted from 50 ml of peritoneal wash from 11 SGC patients before and after cisplatin-based IPC. The gene expression levels of survivin, c-myc, transforming growth factor-beta (TGF-beta), interleukin-2 (IL-2), IL-6, and IL-12 were analyzed using real-time reverse transcription-polymerase chain reaction (RT-PCR) assays. Also, carcinoembrionic antigen (CEA) messenger RNA (mRNA) was used to identify the number of gastric cancer cells in peritoneal washes by the real-time RT-PCR method. The gene expression levels of cytokines and the number of cancer cells in the peritoneal cavity were compared before and after cisplatin-based IPC treatment.

RESULTS

Before IPC, the gene expression of IL-2 from peritoneal washes of patients was significantly suppressed compared to the controls (p = 0.029); however, other gene expression levels did not differ. In 7 cases, more than 90% of the cancer cells were removed from the peritoneal cavity after cisplatin-based IPC. These 7 cases were named the IPC effective group, and the remaining 4 cases were named the IPC ineffective group. In the IPC effective group, elevated IL-2 and IL-6 genes were detected in 5 (71%) and in 6 (86%) after IPC. The correlation between IPC effectiveness and elevated gene expression after IPC (IL-2: p = 0.137, and IL-6: p = 0.044) was observed. However, the 50% survival period of the IPC effective group (9 months) was not different from that of that of the IPC ineffective group (6 months, p = 0.267).

CONCLUSION

IPC effectiveness may correlate with elevation of gene expression of inflammatory cytokines, such as IL-2 and IL-6 in the peritoneal cavity after IPC. However, the prognostic benefits of IPC for SGC patients remain unclear.