Prognostic Impact of Immune-Related Gene Expression in Preoperative Peripheral Blood from Gastric Cancer Patients

BACKGROUND

Anti-PD-1 therapy has shown a promising clinical outcome in gastric cancer (GC). We evaluated the clinical significance of systemic immune-related gene expression in GC patients who underwent surgery.

METHODS

The correlation between the preoperative PD-1, PD-L1, and CD8 mRNA levels in peripheral blood (PB) and clinicopathological factors, including survival, in 372 GC patients was evaluated using quantitative RT-PCR. PD-1- and PD-L1-expressing cells were identified by flow cytometric analysis.

RESULTS

The PD-1, PD-L1, and CD8 mRNA levels in GC patients were significantly higher than those in normal controls, respectively (all P < 0.0001). The levels of each gene were positively correlated with those of the other two genes (all P < 0.0001). GC patients with low PD-1, high PD-L1, and low CD8 mRNA levels had significantly poorer overall survival (OS) than those with high PD-1, low PD-L1, and high CD8 mRNA levels, respectively (P < 0.01, P < 0.05, and P < 0.05, respectively). Multivariate analysis showed that low PD-1 and high PD-L1 mRNA levels were independent poor prognostic factors for OS (PD-1: HR 2.38, 95% CI 1.27-4.78, P < 0.01; PD-L1: HR 1.81, 95% CI 1.15-2.78, P < 0.05). PD-1 and PD-L1 expression occurred on T cells (> 90%) and T cells or monocytes (> 70%), respectively.

CONCLUSIONS

The PD-1, PD-L1, and CD8 mRNA levels in preoperative PB reflected the anti-tumour immune response, and the low PD-1 and high PD-L1 mRNA levels in PB were independent poor prognostic markers in GC patients who underwent surgery.

The impact of pre-operative chemotherapy in patients with peritoneal lavage cytology positive or localized peritoneum metastasis for gastric cancer: A multicenter retrospective study

95

Background: Peritoneal lavage cytology of positive and localized peritoneum metastasis of gastric cancer (GC) are defined as CY1 and P1 in the 14th edition of the Japanese Classification of GC. Patients (pts) with CY1 and/or P1 have poor prognosis after removing all macroscopically visible disease by standard gastrectomy followed by S1. The aim of this study was to investigate the efficacy of pre-operative chemotherapy (Pre-Cx) in patients with CY1 and/or P1. Methods: We retrospectively reviewed the GC pts who were diagnosed to have CY1 and/or P1 at 34 institutions participating in the Stomach Cancer Group of Japan Clinical Oncology Group between 2007 and 2012. Inclusion criteria were: no distant metastasis other than CY1 or P1, no prior treatment for GC. The subjects were divided to two groups according to treatment strategy with/without Pre-Cx before surgery. In the Pre-Cx group, status of CY and P was diagnosed by laparoscopy before and after Pre-Cx, and indication of surgical resection was decided by each physician. Results: A total of 824 pts were collected from 34 institutions. Of the 713 eligible pts, 150 pts received Pre-Cx (Pre-Cx group) and 563 pts underwent surgery followed by Cx (Post-Cx group). Proportions of P0CY1/P1CY0/P1CY1 were 69/12/19% and 69/17/14% in the Pre- and Post-Cx. Cx regimen for Pre-Cx were S1 plus cisplatin/ docetaxel and cisplatin plus S1/others (n=90/37/23). In the Pre-Cx, 57 (38%) pts who achieved P0CY0 after Pre-Cx showed better survival than the remaining 92 pts (overall survival (OS), 31.0 vs. 19.9 months (M), HR=1.99, 95% CI 1.32-2.93, p=0.001). OS was 24.8 and 24.0 M in the Pre- and Post-Cx (HR 1.07; 95% CI 0.87-1.32, p=0.502). In multivariate analysis, P1CY1, over 65 years old and clinical N3 lymph node metastasis were identified as the independent prognostic factor for OS (p<0.05). Conclusions: Although Pre-Cx showed favorable survival in case of achieving P0 and CY0, Pre-Cx did not show a survival benefit for GC pts with CY1 and /or P1.

Three-year outcomes of two phase II studies of adjuvant chemotherapy with S-1 plus oxaliplatin or capecitabine plus oxaliplatin in patients with stage III gastric cancer after D2 gastrectomy

94

Background: Two phase II trials of oxaliplatin-based adjuvant chemotherapy for patients (pts) with gastric cancer (GC) after D2 gastrectomy have been conducted in Japan; the J-CLASSIC study of capecitabine plus oxaliplatin (CAPOX) and the SOXaGC study of S-1 plus oxaliplatin (SOX). In the current study, we evaluated survival outcomes of the two trials. Methods: The J-CLASSIC, enrolling stage II and III pts from 12 centers between July 2012 and July 2013, evaluated eight cycles of CAPOX. The SOXaGC, enrolling stage III pts from 11 centers between July 2013 and February 2014, evaluated seven cycles of SOX after one cycle of S-1 monotherapy. The two studies were conducted sequentially and most centers (9 centers) participated in both trials. In this pooled analysis, we updated relapse-free survival (RFS) and overall survival (OS) information. The median follow-up time was 49 months in the J-CLASSIC and 39 months in the SOXaGC. Results: Fifty-nine stage III pts treated with CAPOX and 62 stage III pts treated with SOX were analyzed. The 3-year RFS and OS rates of SOX were 70.9% (57.8-80.5%) and 75.7% (63.0-84.6%), respectively, whereas the 3-year RFS and OS rates of CAPOX were 67.8% (54.3-78.1%) and 79.3% (66.5-87.7%), respectively. The hazard ratio (HR) of SOX in comparison to CAPOX was 0.925 (0.498-1.720) for RFS, suggesting the efficacy of the two treatments was similar. Trend of a different efficacy was observed in some particular subgroups; the HR for RFS was 1.732 (0.506-5.927) in the intestinal type and 0.735 (0.353-1.528) in the diffuse type, while that was 2.008 (0.447-9.016) in stage IIIA, 0.872 (0.266-2.857) in stage IIIB, and 0.597 (0.258-1.383) in stage IIIC. Conclusions: This is the first report of survival follow-up in Japanese GC pts with oxaliplatin-based adjuvant chemotherapy, which suggests comparable outcomes in both treatments for stage III GC. Different trend in the treatment effect by histologic type or stage warrants further evaluation in a larger cohort. Clinical trial information: UMIN000026883.

Comparison of S-1 and S-1 plus cisplatin as post-operative chemotherapy for gastric carcinoma with peritoneal lavage cytology positive or localized peritoneum metastasis: A multicenter retrospective study

109

Background: Peritoneal lavage cytology of class V and localized peritoneum metastasis of gastric cancer (GC) are defined as CY1 and P1 in the 14th edition of the Japanese Classification of GC. Because patients (pts) with CY1 and/or P1 have poor prognosis after resecting all macroscopically visible disease by standard surgical resection, post-operative chemotherapy (post-Cx) is commonly performed in the clinical practice in Japan. However, no standard chemotherapy has not been established. The aim of this study was to investigate the efficacy of post-Cx in patients with CY1 and/or P1. Methods: We retrospectively reviewed the GC pts who were diagnosed to have CY1 and/or P1 at 34 institutions participating in the Stomach Cancer Group of Japan Clinical Oncology Group between 2007 and 2012. Inclusion criteria were: PS 0-2, histology of adenocarcinoma, no distant metastasis other than CY1 or P1, no prior treatment for GC. The subject of this study was the patients who received surgery followed by post-Cx. Results: A total of 824 pts were collected from 34 institutions. Of the 506 eligible pts, 444 pts underwent standard gastrectomy followed by post-Cx: S-1 (n=267), S1 plus cisplatin (SP) (n=114) or others (n=63). 62 pts did not receive post-Cx (non-Cx). Median age for the S1/SP/Others/non-Cx group were 69/63/66/75. In the S-1 group, pts with P0CY1/P1CY0/P1CY1 were 197/44/26, and those were 81/21/12 in SP, 45/9/9 in Others, and 44/7/11 in non-Cx. Conclusions: Post-Cx may have survival benefit after surgery for GC with CY1 or P1, while there seems no additional benefit over S-1. [Table: see text]

Long-term outcomes of laparoscopy-assisted distal gastrectomy with suprapancreatic nodal dissection for clinical stage I gastric cancer: a multicenter phase II trial (JCOG0703)

BACKGROUND

Laparoscopic gastrectomy has become a common surgical treatment for gastric cancer in eastern Asian countries. However, a large-scale prospective study to investigate the benefit of laparoscopy-assisted distal gastrectomy (LADG) regarding long-term outcomes has never been reported. We have already reported the short-term outcomes of this study. Here we report long-term outcomes as the secondary endpoints of this study after a 5-year follow-up period.

METHODS

This study comprised patients with clinical stage I gastric cancer who were able to undergo a distal gastrectomy. LADG with D1 plus suprapancreatic lymph node dissection was performed by credentialed gastric surgeons who had each conducted at least 30 LADG and 30 open gastrectomy procedures. The primary endpoint was the proportion of patients who developed either anastomotic leakage or pancreatic fistula. The secondary endpoints included overall survival and relapse-free survival.

RESULTS

From November 2007 to September 2008, 176 eligible patients were enrolled, comprising 140 patients with pathological stage IA disease, 23 patients with pathological stage IB disease, 9 patients with pathological stage II disease, and 4 patients with pathological stage IIIA disease. No patients had recurrent disease, and three of the patients died within the follow-up period. The 5-year overall survival was 98.2% (95% confidence interval 94.4-99.4%) and the 5-year relapse-free survival was 98.2% (95% confidence interval 94.4-99.4%).

CONCLUSIONS

The long-term outcomes of stage I gastric cancer patients undergoing LADG seem comparable to those of patients undergoing an open procedure, although this result should be confirmed by a randomized control trial. We have already completed accrual of 921 patients for a multicenter randomized phase III trial (JCOG0912) to confirm the noninferiority of LADG compared with open gastrectomy in terms of relapse-free survival.

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.

Immunochemotherapy using rituximab (RTX) and high-dose methotrexate (HD-MTX): an evaluation of the addition of RTX to HD-MTX in recurrent primary central nervous system lymphoma (PCNSL)

Background

There is increasing evidence that MTX-based chemotherapy is superior to HD-MTX alone. Rituximab (RTX) is effective in a variety of B-cell lymphomas and may enter the brain. The purpose of this study is to evaluate the addition of RTX to HD-MTX in recurrent primary central nervous system lymphoma (PCNSL).

Methods

Patients diagnosed with recurrent PCNSL at our institution between 2004 and 2009 were treated with HD-MTX (3.5-5.5 g/m2) every 2 weeks. From 2010, RTX (375 mg/m2) was administered every 2 weeks along with HD-MTX.

Results

Fifteen recurrences in 10 patients were treated with HD-MTX alone (MTX group). Another 15 recurrences in 10 patients were treated with RTX and HD-MTX (RTX group). In 13 (86.6%) of the 15 recurrences in both groups the pre-planned chemotherapy cycles were completed. In the MTX group, 10/15 (66.6%) recurrences achieved a complete response (CR/CRu), 2/15 (13.3%) recurrences achieved a partial response (PR) and 3/15 (20%) recurrences had progressive disease (PD). In the RTX group, the CR/CRu, PR and PD rates were the same as that in the MTX group. The median time to tumor progression (mTTP) was 9.1 months (range, 1.4-120.9 months) in the MTX group and 7.8 months (range, 0.9-52.3 months) in the RTX group. We found no significant difference in mTTP (9.1 vs. 7.8 months, HR 1.02, 95% CI 0.48-2.18, P = 0.94) between the two groups. All treatment-related toxicities were manageable without any severe events.

Conclusions

The addition of RTX to HD-MTX may not be a promising strategy for recurrent PCNSL. A future study with a larger sample size, longer follow-up, or different RTX dosing/schedule is warranted.

Expression levels of UL16 binding protein 1 and natural killer group 2 member D affect overall survival in patients with gastric cancer following gastrectomy

UL16 binding protein 1 (ULBP1) expressed on the tumor cell surface binds to the natural killer group 2 member D (NKG2D) receptor presenting on natural killer (NK), cluster of differentiation (CD)8⁺ T, and γ δ T cells. However, the roles of ULBP1 and NKG2D expression and associated immune responses in gastric cancer are unclear. The present study investigated the associations between ULBP1 and NKG2D expression and clinical outcomes in patients with gastric cancer. The levels of ULBP1 and NKG2D expression were examined in human gastric cancer cell lines and gastric cancer tissues from 98 patients who underwent surgery from 2004 to 2008. MKN-74 cells expressed ULBP1 with ULBP2, -5, or -6. NKG2D was expressed at a higher level following activation of T cells and NK cells. Among the tissue sections positive for NKG2D expression, 6 patients were positive for CD8 and CD56. In all tissues, NKG2D-expressing cells were typically aCD8⁺ T cells. Patients with NKG2D expression in tumors exhibited significantly longer overall survival (OS) compared with patients without NKG2D expression in tumors (P=0.0217). The longest OS was observed in patients positive for ULBP1 and NKG2D, whereas the shortest OS was observed in patients negative for ULBP1 and NKG2D. The interaction between ULBP1 and NKG2D may improve OS in patients with gastric cancer, and may have applications in immunotherapy for the induction of adaptive immunity in patients with cancer. Additionally, ULBP1 and NKG2D may be useful as prognostic biomarkers in gastric cancer.

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.

Incidence of and risk factors for preoperative deep venous thrombosis in patients undergoing gastric cancer surgery

BACKGROUND

Pulmonary thromboembolism (PE) is one of the life-threatening complications of gastric cancer surgery. D-dimer assay is a safe and rapid tool to exclude the presence of deep venous thrombosis (DVT). In July 2012, we started preoperative DVT screening of patients scheduled for gastric cancer surgery using a combination of D-dimer measurements and lower extremity venous ultrasonography to prevent PE.

METHODS

Between July 2012 and August 2015, 976 consecutive patients underwent gastric cancer surgery with preoperative D-dimer screening. Lower extremity venous ultrasonography was performed in patients with a positive D-dimer assay result (greater than 1.0 μg/ml). The incidence of and risk factors for preoperative DVT and the incidence of PE were examined in patients undergoing gastric cancer surgery.

RESULTS

Of the 976 patients, 176 (18.0%) showed positive D-dimer assay results, and in 13 (1.3%) DVT was diagnosed by lower extremity ultrasonography. Our analysis identified neoadjuvant chemotherapy as a risk factor for preoperative detection of DVT in patients undergoing gastric cancer surgery (P = 0.021). The incidence of PE was 0.1% (1/976).

CONCLUSION

Preoperative gastric cancer patients receiving neoadjuvant chemotherapy seem to be at higher risk for the development of DVT.

Genes involved in development and differentiation are commonly methylated in cancers derived from multiple organs: a single-institutional methylome analysis using 1007 tissue specimens

The aim of this study was to clarify the significance of DNA methylation alterations shared by cancers derived from multiple organs. We analyzed single-institutional methylome data by single-CpG-resolution Infinium assay for 1007 samples of non-cancerous tissue (N) and corresponding cancerous tissue (T) obtained from lung, stomach, kidney, breast and liver. Principal component analysis revealed that N samples of each organ showed distinct DNA methylation profiles, DNA methylation profiles of N samples of each organ being inherited by the corresponding T samples and DNA methylation profiles of T samples being more similar to those of N samples in the same organ than those of T samples in other organs. In contrast to such organ and/or carcinogenetic factor-specificity of DNA methylation profiles, when compared with the corresponding N samples, 231 genes commonly showed DNA hypermethylation in T samples in four or more organs. Gene ontology enrichment analysis showed that such commonly methylated genes were enriched among “transcriptional factors” participating in development and/or differentiation, which reportedly show bivalent histone modification in embryonic stem cells. Pyrosequencing and quantitative reverse transcription-PCR revealed an inverse correlation between DNA methylation levels and mRNA expression levels of representative commonly methylated genes, such as ALX1, ATP8A2, CR1 and EFCAB1, in tissue samples. These data suggest that disruption of the differentiated state of precancerous cells via alterations of expression, independent of differences in organs and/or carcinogenetic factors, may be a common feature of DNA methylation alterations during carcinogenesis in multiple organs.

Clinical outcomes of early gastric cancer patients after noncurative endoscopic submucosal dissection in a large consecutive patient series

BACKGROUND

Clinical outcomes of early gastric cancer (EGC) patients after noncurative endoscopic submucosal dissection (ESD) have not been fully elucidated; we therefore aimed to clarify these outcomes.

METHODS

A total of 3058 consecutive patients with 3474 clinically diagnosed EGCs at initial onset underwent ESD with curative intent at our hospital between 1999 and 2010. We retrospectively assessed the following clinical outcomes of noncurative gastric ESD patients with a possible risk of lymph node (LN) metastasis by dividing patients into two groups with different treatment strategies (additional gastrectomy and simple follow-up): presence of LN metastasis at the time of gastrectomy, incidence of LN and distant metastases during the follow-up period, clinicopathological factors associated with metastasis, and 5-year disease-specific survival (DSS).

RESULTS

After exclusion of 75 noncurative ESD patients with only a positive horizontal margin, 569 noncurative ESD patients with a possible risk of LN metastasis were identified. Among the 356 patients undergoing additional gastrectomy, LN metastasis was identified in 18 patients. A positive vertical margin with submucosal invasion (odds ratio 3.6) and lymphovascular invasion (odds ratio 3.5) were significantly associated with LN metastasis. The 5-year DSS rate was 98.8 %. Among the 212 patients who underwent simple follow-up, LN and/or distant metastases were found in eight patients. In this group, lymphovascular invasion (hazard ratio 6.6) was significantly associated with metastasis with a 5-year DSS rate of 96.8 %.

CONCLUSIONS

Additional gastrectomy should be performed particularly in noncurative gastric ESD patients with lymphovascular invasion or a positive vertical margin with submucosal invasion.

Abstract 5378: Genes involved in development and differentiation are commonly methylated in cancers derived from multiple organs: A single-institutional methylome analysis using 1007 tissue specimens

Aim: The aim of this study was to clarify the significance of DNA methylation alterations shared by cancers derived from multiple organs.

Background: Little is known about DNA methylation alterations during carcinogenesis shared by various organs. In this single-institutional study, consistency of sample quality, diagnostic criteria and technical platforms may be advantageous for providing an overall view of DNA methylation profiles of cancers arising in multiple organs.

Methods: We analyzed single-institutional methylome data by Infinium HumanMethylation27 or HumanMethylation450 BeadChip (Illumina) for 1,007 samples of non-cancerous tissue (N) and corresponding cancerous tissue (T) obtained from the lung, stomach, kidney, breast and liver.

Results: Principal component analysis revealed that N samples of each organ showed distinct DNA methylation profiles, DNA methylation profiles of N samples of each organ being inherited by the corresponding T samples and DNA methylation profiles of T samples being more similar to those of N samples in the same organ than those of T samples in other organs. We identified 2,636, 2,209, 1,915, 2,914 and 5,665 probes that were aberrantly methylated in lung adenocarcinomas, gastric adenocarcinomas, clear cell renal cell carcinomas, breast cancers (e.g. invasive ductal carcinomas, ductal carcinomas in situ and invasive lobular carcinomas) and hepatocellular carcinomas, respectively, in comparison with the corresponding N samples. When we examined pairs of organs, only 6.9% (between stomach cancers and kidney cancers) to 35.4% (between lung cancers and breast cancers) of aberrantly methylated probes were shared between cancers of any two organs, indicating that the majority of DNA methylation alterations were diverse among multiple organs. In contrast to such organ and/or carcinogenetic factor-specificity of DNA methylation profiles, when compared to the corresponding N samples, 231 genes commonly showed DNA hypermethylation in T samples in four or more organs. Gene ontology enrichment analysis showed that such commonly methylated genes were enriched among “transcriptional factors” participating in development and/or differentiation, which reportedly show bivalent histone modification in embryonic stem cells. Pyrosequencing and quantitative reverse transcription-PCR revealed an inverse correlation between DNA methylation levels and mRNA expression levels of representative commonly methylated genes, such as ALX1, ATP8A2, CR1 and EFCAB1, in tissue samples.

Conclusion: These data suggest that disruption of the differentiated state of precancerous cells via alterations of expression, independent of differences in organs and/or carcinogenetic factors, may be a common feature of DNA methylation alterations during carcinogenesis in multiple organs.

Citation Format: Kentaro Ohara, Eri Arai, Yoriko Takahashi, Nanako Ito, Ayako Shibuya, Koji Tsuta, Ryoji Kushima, Hitoshi Tsuda, Hidenori Ojima, Hiroyuki Fujimoto, Shun-ichi Watanabe, Hitoshi Katai, Takayuki Kinoshita, Tatsuhiro Shibata, Takashi Kohno, Yae Kanai. Genes involved in development and differentiation are commonly methylated in cancers derived from multiple organs: A single-institutional methylome analysis using 1007 tissue specimens [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5378. doi:10.1158/1538-7445.AM2017-5378

Phase III trial to evaluate the efficacy of neoadjuvant chemotherapy with S-1 plus oxaliplatin followed by D2 gastrectomy with adjuvant S-1 in locally advanced gastric cancer: Japan Clinical Oncology Group study JCOG1509 (NAGISA trial)

TPS4134

Background: In Japan, while post-operative adjuvant chemotherapy with S-1 or capecitabine plus oxaliplatin is standard care for pStage II/III gastric cancer after curative resection with D2 lymph node dissection, the clinical outcomes of pStage III patients are not satisfactory. In Europe, neoadjuvant chemotherapy (NAC) followed by gastrectomy is standard. The Japan Clinical Oncology Group (JCOG) has conducted several phase II trials of NAC, and deemed NAC as one of the most promising treatment strategies for gastric cancer with lymph node metastasis (Stage III). However, no established criteria exists for diagnosis of lymph node metastasis. JCOG1302A which was a cross-sectional study evaluating the accuracy of preoperative staging by imaging, showed that cT3-4N1-3M0 (positive lymph node was defined as that with a long axis diameter ≥ 10 mm or short axis diameter ≥ 8 mm) included just 6.5% overdiagnosed pStage I patients and accounted for 52.6% of all pStage III patients. Methods: JCOG1509 (UMIN000024065) is designed as a randomized phase III study to confirm the survival superiority of addition of NAC to standard treatment for patients with cT3-4N1-3M0 gastric cancer. In the standard arm, a gastrectomy with D2 lymphadenectomy is performed followed by adjuvant chemotherapy with oral S-1 for 1 year. In the experimental arm, combination of an infusion of oxaliplatin (130 mg/m2/day, day 1) and oral S-1 (80 mg/m2/day, days 1–14) is repeated every 3 weeks for 3 courses before gastrectomy, followed by surgery and adjuvant chemotherapy with S-1 for 1 year. The primary endpoint is overall survival. The planned sample size is 470 in total with a 1-sided alpha of 5%, a power of 80%, expecting a 10% increase in the 5-year OS (60% vs 70%). Patients will be enrolled from 58 Japanese institutions over 3.5 years. The study was activated in September 2016 and, as of January 2017, 18 patients were enrolled for the study. Clinical trial information: UMIN000024065.

TOP2A, GGH, and PECAM1 are associated with hematogenous, lymph node, and peritoneal recurrence in stage II/III gastric cancer patients enrolled in the ACTS-GC study

Background

To identify factors related to relapse sites, we carried out an exploratory biomarker analysis of data from the Adjuvant Chemotherapy Trial of TS-1 for Gastric Cancer study, which is a randomized, controlled trial comparing postoperative adjuvant S-1 therapy with surgery alone in 1,059 patients with stage II/III gastric cancer.

Patients and Methods

Surgical specimens from 829 patients were retrospectively examined, and 63 genes involved in a variety of biological processes were analyzed by quantitative real-time PCR. Gene expression normalized to reference genes was categorized as lower or higher than the median, and association with relapse sites was analyzed based on 5-year relapse-free survival.

Results

Hematogenous, lymph node, and peritoneal recurrence developed in 72, 105, and 138 of the 829 patients, respectively; hazard ratios were 0.79 (95% confidential interval: 0.54–1.16), 0.51 (0.31–0.82), and 0.60 (0.42–0.84), respectively. Expression of platelet/endothelial cell adhesion molecule 1 (PECAM1) and topoisomerase II alpha (TOP2A) was strongly correlated with hematogenous recurrence and peritoneal recurrence, respectively (false discovery rate = 7.7×10⁻⁵ and 0.002, respectively). Gamma-glutamyl hydrolase (GGH) expression was moderately correlated with lymph node recurrence (false discovery rate = 0.34). Relapse-free survival was worse in patients expressing high levels of PECAM1 (hazard ratio = 2.37, 1.65–3.41), TOP2A (hazard ratio = 2.35, 1.55–3.57), or GGH (hazard ratio = 1.87, 1.13–3.08), respectively. A multivariate analysis revealed that these were stronger independent risk factors than tumor histological type.

Conclusion

In patients with stage II/III gastric cancer, TOP2A, GGH, and PECAM1 levels in primary tumors are linked to high risk of hematogenous, lymph node, and peritoneal recurrence, respectively.

Clinical outcomes of gastric polyps and neoplasms in patients with familial adenomatous polyposis

Background and study aims Familial adenomatous polyposis (FAP) is an autosomal dominant syndrome caused by a germline mutation in the adenomatous polyposis coli (APC) gene, characterized by the presence of more than 100 adenomatous polyps in the colorectum. The upper gastrointestinal tract is an extracolonic site for malignancy in patients with FAP. The frequency of death in Japanese patients with FAP because of gastric cancer is 2.8 % and that because of colon cancer is 60.6 %. Few studies have reported upper gastrointestinal diseases in patients with FAP. In the present study, we investigated the clinical outcomes of patients with FAP diagnosed with gastric neoplasms. Patients and methods We enrolled 80 patients with FAP who underwent esophagogastroduodenoscopy from October 1997 to December 2011. We investigated patient characteristics, endoscopic findings of gastric lesions, treatment outcomes, and long-term courses. Results Fundic gland polyposis was observed in 51 patients (64 %) and gastric neoplasms in 22 patients (28 %), including 20 with non-invasive and 2 with invasive neoplasm. Of the 26 neoplasms, 11 were treated by endoscopic resection (ER) and 4 by surgical resection. Metachronous gastric neoplasms were observed in 7 patients (15 lesions) and treated by ER, except for in 1 patient. No patients died of gastric lesions during a median follow-up period of 6.5 years (range, 0 - 14). Conclusion Because gastric lesions including gastric cancers in patients with FAP did not cause any deaths, they can be considered to have favorable prognoses. Early detection of gastric neoplasms through an appropriate follow-up interval may have contributed to these good outcomes.

A phase II study of preoperative chemotherapy with docetaxel, cisplatin, and S-1 followed by gastrectomy with D2 plus para-aortic lymph node dissection for gastric cancer with extensive lymph node metastasis: JCOG1002

BACKGROUND

Gastric cancer with extensive lymph node metastasis is commonly considered unresectable, with a poor prognosis. We previously reported the results of the use of cisplatin and S-1 as preoperative chemotherapy for gastric cancer with extensive lymph node metastasis; docetaxel, cisplatin, and S-1 (DCS) have now been investigated for the same purpose.

METHODS

Patients received two or three 28-day cycles of DCS therapy (docetaxel at 40 mg/m² and cisplatin at 60 mg/m² on day 1, S-1 at 40 mg/m² twice daily for 2 weeks) followed by gastrectomy with D2 plus para-aortic nodal dissection. After R0 resection, S-1 chemotherapy was given for 1 year. The primary end point was the response rate (RR) to preoperative chemotherapy determined by central peer review according to the Response Evaluation Criteria in Solid Tumors version 1.0. The planned sample size was 50, with one-sided alpha of 10 %, power of 80 %, expected RR of 80 %, and threshold of 65 %.

RESULTS

Between July 2011 and May 2013, 53 patients were enrolled, of whom 52 were eligible. The clinical RR was 57.7 % [30/52, 80 % confidence interval 47.9-67.1 %, p = 0.89], and R0 resection was achieved in 84.6 % of patients (44/52). Common grade 3 or grade 4 adverse events during DCS therapy were leukocytopenia (18.9 %), neutropenia (39.6 %), and hyponatremia (15.1 %). The common grade 3 or grade 4 surgical morbidity was abdominal infection (10.2 %). The pathological RR was 50.0 % (26/52).

CONCLUSIONS

Preoperative DCS therapy was feasible but did not show a sufficient RR. Preoperative cisplatin and S-1 therapy is still considered the tentative standard treatment for this population until survival results are known.

Prognostic factors for survival in patients with pT1 N+ or T2–3 N0 gastric cancer in Japan

Background

The outcome for pT1 N+ or pT2–3 N0 gastric cancer is favourable, but some patients suffer from recurrent disease. The aim of this study was to identify prognostic factors in patients with pT1 N+ or pT2–3 N0 gastric cancer.

Methods

This was a multicentre, retrospective cohort study. All patients with pT1 N+ or pT2–3 N0 gastric cancer who underwent curative gastrectomy at five high-volume, specialized cancer centres in Japan between 2000 and 2008 were included. Demographic, clinical, surgical and pathological data were collected. Independent prognostic factors were identified using a Cox proportional hazards regression model.

Results

Some 1442 patients were included. The 5-year overall survival rate for patients with pT1 N+ or pT2–3 N0 gastric cancer was 92·0 per cent. Multivariable analysis for overall survival identified age (hazard ratio (HR) 2·67, 95 per cent c.i. 2·09 to 3·43), sex (HR 0·57, 0·39 to 0·83) and clinical tumour depth (cT) (HR 1·45, 1·06 to 1·98) as independent prognostic factors.

Conclusion

Survival of patients with pT1 N+ or pT2–3 N0 gastric cancer is good. Age 65 years or above, male sex and cT2-4 category are associated with worse overall survival.

Effectiveness and limitations of staging laparoscopy for peritoneal metastases in advanced gastric cancer from the results of JCOG0501: A randomized trial of gastrectomy with or without neoadjuvant chemotherapy for type 4 or large type 3 gastric cancer

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Background: In type 4 or large type 3 gastric cancer diagnosed as not having distant metastasis by imaging modalities, the incidence of peritoneal metastasis that was unexpectedly found during laparotomy was approximately 40%. Staging laparoscopy (SL) is a valuable method used for staging gastric cancer. This study aimed to clarify the effectiveness and limitations of SL for patients (pts) with type 4 or large type 3 gastric cancer. Methods: JCOG0501 is a randomized phase III trial of gastrectomy with or without neoadjuvant S-1 plus cisplatin for treating type 4 or large type 3 gastric cancer. Eligibility criteria included histologically proven gastric adenocarcinoma that was clinically type 4 or large type 3 gastric cancer and was diagnosed as R0/1-resectable using SL. Pts who underwent gastrectomy without neoadjuvant chemotherapy were included in this study. Results: In total, 316 pts (158 pts with and without neoadjuvant chemotherapy each) were enrolled between October 2005 and July 2013 from 44 institutions. Of the 158 pts without neoadjuvant therapy, 2 pts did not receive laparotomy. The remaining 156 pts were included in this analysis. Among them, except for 1 patient (P1), none were diagnosed with peritoneal metastases (P0) during SL. Among these 155 pts, 24 (15.5%) were diagnosed with peritoneal metastases at subsequent laparotomies (false-negative). Most of the overlooked peritoneal disseminated nodules were located in the intestinal mesentery (8 pts), transverse mesocolon (5 pts), or omental bursa (3 pts). The total number of peritoneal disseminated nodules at laparotomy was often ≤ 9 (1–3 nodules in 14 pts, 4–9 in 4 pts). Of the 156 included pts, 142 underwent R0/1-resection (91.0%) because some overlooked nodules were curatively resected. Conclusions: SL is a useful diagnostic tool to plan the management of type 4 and large type 3 gastric cancers, although the high false-negative rate cannot be ignored. In SL, detailed exploration of the mesentery, mesocolon, and omental bursa is recommended.