Early administration of postoperative BCAA-enriched PPN may improve lean body mass loss in gastric cancer patients undergoing gastrectomy.

BACKGROUND: It has been reported that weight loss or lean body mass (LBM) loss after gastrectomy for gastric cancer is associated with prognosis and nutritional support alone is insufficient to prevent LBM loss. Branched-chain amino acids (BCAA) play an important role in muscle catabolism, however their clinical effects on suppression of LBM loss in gastric cancer patients undergoing gastrectomy remains elusive. In this current study, we investigated the effect of our original PPN regimen including BCAA (designated to BCAA-regimen) on LBM loss. METHODS: We conducted a randomized controlled trial (RCT) at a single institution where patients undergoing gastrectomy were assigned to either receive a five-day early postoperative course of the BCAA-regimen (BCAA group) or conventional nutrition. The primary endpoint was the % reduction in LBM at postoperative day 7. The secondary endpoints included the % reduction in LBM at 1 and 3 months postsurgery. RESULTS: At postoperative day 7, LBM loss in the BCAA group tended to be lower than in the control group (0.16% vs. 1.7%, respectively; P = 0.21), while at 1 month postsurgery, LBM loss in the BCAA group was significantly different to that of the control group (- 0.3% vs. 4.5%, respectively; P = 0.04). At 3 months postgastrectomy, however, LBM loss was similar between the BCAA and the control groups. CONCLUSION: Our RCT clinical trial clarified that early administration of the postoperative BCAA regimen improved LBM loss at 1 month after surgery in gastric cancer patients undergoing gastrectomy.

Pancreas-contactless gastrectomy for gastric cancer prevents postoperative inflammation.

BACKGROUND: Pancreas-related complications after laparoscopic gastrectomy (LG) for gastric cancer can be fatal. We developed a gastrectomy procedure with no pancreas contact to prevent such complications and herein report the surgical outcomes. METHODS: We retrospectively reviewed 182 consecutive patients with gastric cancer who underwent LG at Kitasato University Hospital from January 2017 to January 2020. These patients were divided into a pancreas-contact group (C group) and pancreas-contactless group (CL group) for comparison of postoperative complications, and inflammatory parameters such as body temperature (BT) and C-reactive protein (CRP). RESULTS: Postoperative complications of CDc grade ≧ IIIa were significantly fewer in the CL group than in the C group [0/76 (0%) vs. 6/106 (5.7%), P = 0.035]. The median drain amylase (drain-AMY) on postoperative day 1 (POD1) was significantly lower in the CL group than in the C group (641 vs. 1162 IU/L, P = 0.02), as was BT at POD1 (37.4 °C vs. 37.7 °C, P = 0.04), the patient group with a BT above 37.5 °C at POD3 [5/76 (6.5%) vs. 18/106 (17%), P = 0.037], and those showing a CRP above 20.0 mg/dL at POD3 [5/76 (6.5%) vs. 20/106 (19%), P = 0.018]. CONCLUSIONS: Our technique to prevent pancreas contact during supra-pancreatic lymph node dissection during LG could minimize the inflammatory response and prevent further postoperative complications. Further large-scale, prospective studies are now required.

Improved anastomotic technique for esophagojejunal anastomosis using circular stapler.

PURPOSE: In total gastrectomy, Roux-en-Y reconstruction with esophagojejunal anastomosis has been widely used in gastrointestinal reconstruction. In the case of anastomotic leakage of RY reconstruction, esophagojejunal anastomosis should be paid attention, and esophageal fragility is considered the reason for the leakage. Here, we introduce an atraumatic and innovative technique for esophagojejunostomy. METHODS: We prospectively performed routine novel esophagojejunal anastomosis using circular stapler device and reviewed the records of 14 consecutive patients with gastric cancer who underwent open total gastrectomy at Kitasato University Hospital from April 2019 to March 2020. By placing about 10 stay sutures around the entire esophageal stump, the esophageal stump can be opened to the maximum diameter. The forceps grasping the tissue was not necessary for these procedures, consequently preventing either tears the esophageal stump tissue or narrowing the esophageal lumen. RESULTS: These 14 cases were far advanced cases of gastric cancer, 6 cases of splenectomy and 3 cases of distal pancreatectomy. No technical problems such as esophageal tear were observed in all cases. Postoperative complications were observed in 6 patients (42.9%), and their contents varied. However, they all improved conservatively. Regarding anastomotic complications, anastomotic leakage of Clavien-Dindo-II was observed in one case, but it improved conservatively. CONCLUSION: Our new atraumatic anastomosis technique could abolish problems such as tear of esophagus wall due to introduce a larger-sized anvil, trauma of esophageal wall by grasping with forceps such as Alice or Babcock. Consequently, the atraumatic and innovative technique might make the esophagojejunostomy safe. This method might prevent anastomotic leakage and other complications effectively.

Prospective study to validate the clinical utility of DNA diagnosis of peritoneal fluid cytology test in gastric cancer.

The clinical efficacy of DNA cytology test (CY) in gastric cancer (GC) has been retrospectively proposed using cancer-specific methylation of cysteine dioxygenase type 1 (CDO1). We confirmed the clinical utility of DNA CY in a prospective cohort. Four hundred GC samples were prospectively collected for washing cytology (UMIN000026191), and detection of the DNA methylation of CDO1 was assessed by quantitative methylation-specific PCR in the sediments. Endpoint was defined as the match rate between conventional CY1 and DNA CY1 (diagnostic sensitivity), and the DNA CY0 rate (diagnostic specificity) in pStage IA. DNA CY1 was detected in 45 cases (12.5%), while CY1 was seen in 31 cases (8.6%) of 361 chemotherapy-naïve samples, where the sensitivity and specificity of the DNA CY in the peritoneal solutions were 74.2% and 96.5%, respectively. The DNA CY was positive for 3.5/0/4.9/11.4/58.8% in pStage IA/IB/II/III/IV, respectively (P < .01). In the multivariate analysis, DNA CY1 was independently correlated with pathological tumor depth (pT) (P = .0012), female gender (P = .0099), CY1 (P = .0135), P1 (P = .019), and carcinoembryonic antigen (CEA) (P = .036). The combination of DNA CY1 and P factor nearly all covered the potential peritoneal dissemination (P1 and/or CY1 and/or DNA CY1) (58/61:95.1%). DNA CY1 had a significantly poorer prognosis than DNA CY0 in GC patients (P < .0001). DNA CY1 detected by CDO1 promoter DNA methylation has a great value to detect minimal residual disease of the peritoneum in GC clinics, representing poor prognosis as a novel single DNA marker.

The incidences of metachronous multiple gastric cancer after various types of gastrectomy: analysis of data from a nationwide Japanese survey.

BACKGROUND: The incidence of metachronous multiple gastric cancer (MMGC) after gastrectomy remains unclear. This study evaluated the incidences of MMGC according to specific gastrectomy types, including pylorus-preserving gastrectomy (PPG), proximal gastrectomy (PG), and function-preserving gastrectomy (FPG), which was categorized as segmental gastrectomy and local resection. METHODS: We conducted a questionnaire survey of the Japanese Society for Gastro-Surgical Pathophysiology members, who were asked to report their institutional numbers of radical gastrectomy cases for cancer between 2003 and 2012. The cases were categorized according to whether the remnant stomach's status was followed for > 5 years, confirmation of MMGC, time to diagnosis, and treatment for MMGC. We calculated the "precise incidence" of MMGC by dividing the number of MMGC cases by the number of cases in which the status of remnant stomach was followed up for > 5 years. RESULTS: The responses identified 33,731 cases of gastrectomy. The precise incidences of MMGC were 2.35% after distal gastrectomy (DG), 3.01% after PPG, 6.28% after PG (p < 0.001), and 8.21% after FPG (p < 0.001). A substantial proportion of MMGCs (36.4%) was found at 5 years after the initial surgery. The rates of MMGC treatment using endoscopic submucosal dissection were 31% after DG, 28.6% after PPG, 50.8% after PG (p < 0.001), and 67.9% after FPG (p < 0.001). CONCLUSIONS: The incidence of MMGC was 2.4% after DG, and higher incidences were observed for larger stomach remnants. However, the proportion of cases in which MMGC could be treated using endoscopic submucosal dissection was significantly higher after PG and FPG than after DG.

Impact of preoperative chemotherapy as initial treatment for advanced gastric cancer with peritoneal metastasis limited to positive peritoneal lavage cytology (CY1) or localized peritoneal metastasis (P1a): a multi-institutional retrospective study.

BACKGROUND: Gastric cancer (GC) patients with peritoneal metastasis are defined as stage IV in the Japanese classification of GC. For patients with peritoneal metastasis limited to positive peritoneal lavage cytology (CY1) and/or localized peritoneal metastasis (P1a), gastrectomy followed by S1 monotherapy is one of the most widely accepted therapeutic strategy in Japan. This study investigated the efficacy of preoperative chemotherapy as initial treatment in GC patients with CY1 and/or P1a. METHODS: We retrospectively reviewed GC patients diagnosed with CY1 and/or P1a at 34 institutions in Japan between 2008 and 2012. Selection criteria were: adenocarcinoma, no distant metastasis except CY1 or P1a, and no prior treatment. The subjects were divided into an Initial-Chemotherapy group and an Initial-Surgery group, according to the initial treatment. RESULTS: A total of 824 patients were collected and 713 eligible patients were identified for this study. As the initial treatment, 150 patients received chemotherapy (Initial-Cx), and 563 patients underwent surgery (Initial-Sx). Initial-Cx regimens were cisplatin plus S1/docetaxel plus cisplatin plus S1/others (n = 90/37/23). Both overall survival (OS) and progression-free survival (PFS) were similar between the Initial-Cx and Initial-Sx groups (median OS 24.8 and 24.0 months, HR 1.07, 95% CI 0.87-1.3; median PFS 14.9 and 13.9 months, HR 1.04, 95% CI 0.85-1.27). The 5-year OS rates were 22.3% in the Initial-Cx group and 21.5% in the Initial-Sx group. CONCLUSIONS: Although, the preoperative chemotherapy did not show a survival benefit for GC patients with CY1 and/or P1a, initial-Cx showed favorable survival in patients who converted to P0 and CY0.

Preoperative chemotherapy could modify recurrence patterns through postoperative complications in patients with gastric cancer.

PURPOSE: Postoperative infectious complications have a negative impact on survival outcomes in patients with gastric cancer. It is recently reported that preoperative chemotherapy may eliminate this negative impact. This study aimed to confirm whether preoperative chemotherapy can eliminate the negative impact of postoperative infectious complications (IC) on survival outcomes and elucidate the association between postoperative infectious complications and recurrence patterns. METHODS: We retrospectively reviewed data of 86 patients who received preoperative chemotherapy with docetaxel, cisplatin, and S-1 followed by R0 gastrectomy at the Kitasato University between 2006 and 2016. Patients who developed grade II or higher infectious complications during hospitalization were grouped into the IC group, while others were grouped into the non-IC (NIC) group. Survival outcomes and recurrence patterns were analyzed between the two groups. RESULTS: Infectious complications with Clavien-Dindo classification of grade II or higher were found in 12 patients (14.0%, IC group). The median observational period was 61 months. Overall survival and progression-free survival were similar in the IC and NIC groups. Recurrence occurred in 39 patients. The proportions of peritoneal and lymph node recurrences were not significantly different between the two groups. However, the proportion of distant metastasis in the IC group was significantly higher than that in NIC group (3/4 [75%] vs. 9/35 [17%], p = 0.04). CONCLUSIONS: Pathological stage after neoadjuvant therapy plays a stronger role in recurrence than postoperative complications. Lymph node and peritoneal metastasis may be suppressed by preoperative chemotherapy.

Randomized study of prevention of gastrointestinal toxicities by nutritional support using an amino acid-rich elemental diet during chemotherapy in patients with esophageal cancer (KDOG 1101).

BACKGROUND: This randomized study was designed to evaluate the clinical effect of an elemental diet during chemotherapy in patients with esophageal cancer. METHODS: The inclusion criteria were as follows: (1) esophageal squamous cell carcinoma, (2) stage IB-IV, (3) schedule to receive docetaxel, cisplatin, and 5-fluorouracil (DCF chemotherapy), (4) 20-80 years old, (5) performance status of 0-2, (6) oral intake ability, and (7) written informed consent. Patients were divided into two groups: the elemental supplementary group and the non-supplementary group. Patients received ELENTAL® (160 g/day) orally 9 weeks after the start of chemotherapy. Primary endpoint was the incidence of grade 2 or higher gastrointestinal toxicity according to the Common Terminology Criteria for Adverse Events, version 4.0. Secondary endpoints were the incidence of all adverse events and the evaluation of nutritional status. RESULTS: Thirty-six patients in the elemental supplementary group and 35 patients in the non-supplementary group were included in the analysis. The incidence of grade 2 or higher gastrointestinal toxicity and all grade 3 or 4 adverse events did not differ significantly between the groups. In the elemental supplementary group, the body weight (p = 0.057), muscle mass (p = 0.056), and blood levels of transferrin (p = 0.009), total amino acids (p = 0.019), and essential amino acids (p = 0.006) tended to be maintained after chemotherapy. CONCLUSION: Nutritional support provided by an amino acid-rich elemental diet was ineffective for reducing the incidence of adverse events caused by DCF chemotherapy in patients with esophageal cancer.

Prediction of Efficacy of Postoperative Chemotherapy by DNA Methylation of CDO1 in Gastric Cancer.

BACKGROUND: CDO1 is a presumed tumor suppressor gene in human cancers, the expression of which is silenced by promoter DNA methylation. Moreover, CDO1 harbors functionally oncogenic aspects through modification of mitochondrial membrane potential. We recently proposed that this oncogenic feature allows for the prediction of the efficacy of postoperative chemotherapy in colon cancer. The present study aims to elucidate the efficacy of prediction of success of postoperative chemotherapy in advanced gastric cancer to improve the treatment strategy of patients. MATERIALS AND METHODS: Forced expression of CDO1 in gastric cancer cell lines was assessed using the JC-1 assay. Promoter DNA methylation was investigated in quantitative TaqMan methylation-specific polymerase chain reaction in 321 pathological stage II/III advanced gastric cancer cases treated by curative gastrectomy with or without postoperative chemotherapy. RESULTS: (1) Forced expression of CDO1 led to increased mitochondrial membrane potential, accompanied by augmented survival in gastric cancer cells under anaerobic conditions. These results suggest that CDO1-expressing cancer cells survive more easily in anaerobic lesions which are inaccessible to anticancer drugs. (2) Intriguingly, in cases with the highest CDO1 methylation (ranging from 15% to 40%), patients with postoperative chemotherapy showed significantly better survival than those with no postoperative chemotherapy. (3) A robust prognostic difference was observed that was explained by differential recurrences of distant metastasis (P = 0.0031), followed by lymph node (P = 0.0142) and peritoneal dissemination (P = 0.0472). CONCLUSIONS: The oncogenic aspects of CDO1 can be of use to determine patients with gastric cancer who will likely respond to treatment of invisible systemic dissemination by postoperative adjuvant chemotherapy.

CD33+ Immature Myeloid Cells Critically Predict Recurrence in Advanced Gastric Cancer.

BACKGROUND: It is elusive which subtypes of immune cells are pivotal in cancer progression and prognosis in gastric cancer (GC). The aim of this study is to clarify clinical impact of immature myeloid-derived immune cells in patients with GC who underwent curative gastrectomy with curative lymphadenectomy and treated with S-1 (tegafur/gimeracil/oteracil) postoperatively. METHODS: The prognostic impact of recruited CD33+ immature myeloid-derived cells were clinicopathologically analyzed in curatively resected stage II and III GC. Correlation of preoperative peripheral leukocyte fractions with recruited CD33+ immature cells was also assessed. RESULTS: Patients with high CD33+ cell counts in primary tumor showed dramatically worse prognosis (5-y recurrence-free survival 29.0%) than that of the counterparts (79.4%). High CD33+ cell counts independently predicted poor prognosis in stage II/III (hazard ratio, 4.34; P < 0.001). In analyses of each stage, high CD33+ cell count was pivotally associated with poor prognosis in both stages. There was no significant correlation of each peripheral leukocyte fraction with CD33+ cell recruitment. Of note, high CD33+ cell count was significantly correlated with hematogenous recurrence. CONCLUSIONS: Recruitment of CD33+ immature myeloid cells critically predict hematogenous recurrences in curatively resected advanced GC. These results give rational to focusing on CD33+ myeloid-derived cells as a novel approach to tackle advanced GC.

Prevention of intra-thoracic recurrent laryngeal nerve injury with robot-assisted esophagectomy.

PURPOSE: Transthoracic esophagectomy for esophageal cancer is one of the most invasive procedures in surgery for gastrointestinal cancer. Serious complications sometimes occur after esophageal cancer surgery, including recurrent laryngeal nerve injury and pneumonia. The purpose of this study was to access the possibility of robot-assisted thoracoscopic esophagectomy for esophageal cancer in terms of preventing recurrent laryngeal nerve injury. METHODS: Operations in thoracic part were performed in prone position with bilateral ventilation. During dissection of the recurrent laryngeal nerve lymph nodes, thin blood vessels were coagulated with Maryland bipolar forceps in the left hand and then dissected with monopolar scissors in the right hand. Especially when dissecting left recurrent laryngeal nerve lymph nodes, the nerve was left unisolated from the vascular sheath that involves the aortic arch. Short-term outcomes including operative time, estimated blood loss, and postoperative complications including recurrent laryngeal nerve injury were accessed. RESULTS: From November 2018 to January 2020, 20 patients underwent robot-assisted thoracoscopic esophagectomy for esophageal cancer. Thoracic operative time was 242 min, estimated blood loss in the thoracic part was minimal, the number of dissected mediastinal lymph nodes was 19 (all median), and the incidence rates of recurrent laryngeal nerve injury and pneumonia were 10% (2 case) and 10% (2 cases), respectively. CONCLUSION: Robot-assisted thoracoscopic esophagectomy for esophageal cancer has the possibility of reducing recurrent laryngeal nerve injury even in the introductory period. Randomized controlled trials are required to confirm this advantage of the robotic surgery.

Patient selection for salvage surgery after definitive chemoradiotherapy in esophageal squamous cell carcinoma.

PURPOSE: With the widespread use of definitive chemoradiotherapy (dCRT) for esophageal squamous cell carcinoma (ESCC), salvage surgery for recurrence/residual patients became prevalent. However, survival impact of salvage surgery remains obscure at present. METHODS: The updated clinical outcomes of salvage surgery were investigated to know its survival impact. Of the 155 ESCC patients who underwent dCRT between 2009 and 2016, we included 85 patients with recurrence or residual disease. The median follow-up was 65 months. RESULTS: Of the 85 patients with progression disease, there were 42 and 43 patients of recurrence and residual disease, respectively. Salvage surgery was performed in 27 patients after dCRT, including 15 patients who underwent salvage esophagectomy. The 5-year overall survival (OS) of salvage surgery and otherwise patients was 66.1% and 14.5%, and the patients with salvage surgery had a significantly better prognosis (p < 0.0001). In the 15 patients who underwent salvage esophagectomy, residual disease, lymph node metastasis-positive (ycN+) after dCRT, and pathological lymph node metastasis-positive (ypN+) were significantly associated with poor prognosis (p = 0.0492, p = 0.0006, p = 0.0276), and the 5-year OS rates for the ycN/ypN combinations were 90%, 33.3%, and 0% in ycN-/ypN-, ycN+/ypN-, and ycN+/ypN+ patients, respectively (p = 0.0026). In a multivariate analysis, ycN+ was an independent poor prognostic factor (HR 13.6, 95% CI 1.65-286.8, p = 0.0154). CONCLUSIONS: Survival impact of salvage surgery after dCRT is robust, and lymph node metastasis after dCRT may help determine the indication for salvage esophagectomy.

Neoadjuvant chemotherapy plus surgery for high-risk advanced gastric cancer: long-term results of KDOG1001 trial.

PURPOSE: The purpose of this study is to evaluate the long-term survival outcomes of KDOG1001 trial after a minimum follow-up of 3 years. METHODS: Patients with bulky N2 lymph nodes, linitis plastica (type 4), or large ulcero-invasive-type tumors (type 3) received up to four 28-day cycles of DCS neoadjuvant chemotherapy (docetaxel at 40 mg/m2, cisplatin at 60 mg/m2 on day 1, and S-1 at 40 mg/m2 twice daily for 2 weeks) followed by gastrectomy with D2 lymphadenectomy plus adjuvant S-1 therapy for 1 year. The final preplanned analysis of long-term outcomes including overall survival and relapse-free survival was conducted after minimum follow-up of 3 years. This trial is registered with the University Hospital Medical Information Network Clinical Trials Registry, number UMIN 000003642, and has been completed. RESULTS: From May 2010 through January 2017, 40 patients were enrolled. All included patients underwent neoadjuvant chemotherapy with DCS followed by gastrectomy with D2 lymphadenectomy, and 32 (80%) completed adjuvant S-1 therapy for 1 year. After a median follow-up for surviving patients of 68 months at the last follow-up in January 2020, 3-year overall survival rate was 77.5% (95% confidence interval 62.1-87.9%), while 3-year relapse-free survival rate was 62.5% (95% confidence interval 46.8-76.0%). CONCLUSION: Neoadjuvant chemotherapy with 4 cycles of DCS followed by D2 gastrectomy plus adjuvant S-1 was associated with relatively good long-term oncologic outcomes for patients with the high-risk gastric cancer.

A phase I study of docetaxel/oxaliplatin/S-1 (DOS) combination neoadjuvant chemotherapy for patients with locally advanced adenocarcinoma of the esophagogastric junction.

BACKGROUND: The optimal dose of each drug used in the docetaxel, oxaliplatin, and S-1 (DOS) chemotherapy remains to be clarified for the Japanese population. The purpose of this study was to determine a recommended dose for a combination neoadjuvant DOS chemotherapy for Japanese patients with locally advanced adenocarcinoma of the esophagogastric junction (AEG). METHODS: Patients with cT3 or more advanced AEG without distant metastasis were eligible for this study. The planned dosages of docetaxel (mg/m2, day 1), oxaliplatin (mg/m2, day 1), and S-1 (mg/day, days 1-14) were: 50/100/80-120 at level 1, and 60/100/80-120 at level 2, respectively. The treatment cycle was repeated every 3 weeks, and patients were assessed for response to the treatment after 2 and 3 cycles. This study was registered in the UMIN Clinical Trial Registry (UMIN 000022210). RESULTS: We enrolled 12 patients with locally advanced AEG in this study. At dose level 1, one of the six patients experienced dose-limiting toxicity (DLT) of grade 3 diarrhea and grade 3 febrile neutropenia. Two of the next six patients also experienced DLT of need for more than 2-week delay of the start of the second cycle due to adverse events at dose level 2. Based on these results, level 2 was considered the recommended dose for this regimen. CONCLUSION: Recommended doses of docetaxel (mg/m2), oxaliplatin (mg/m2), and S-1 (mg/day) were 60/100/80-120. This chemotherapy scheme showed good preliminary efficacy with acceptable toxicity warranting a further phase II trial to investigate the efficacy of this regimen.

A retrospective study of definitive chemoradiotherapy in patients with resectable small cell neuroendocrine carcinoma of the esophagus.

BACKGROUND: Standard treatment for resectable small cell neuroendocrine carcinoma of the esophagus (SCNEC-E) remains to be established. METHODS: We retrospectively studied 7 consecutive patients with resectable SCNEC-E who received definitive chemoradiotherapy (dCRT) to evaluate the safety and efficacy. Treatment consisted of two courses of chemotherapy with cisplatin (80 mg/m2 on day 1) and etoposide (100 mg/m2 on days 1-3) or carboplatin (AUC 5 on day 1) and etoposide (80 mg/m2 on days 1-3) given every 4 weeks during dCRT. The total radiation dose was 50.4 Gy (28 fractions). RESULTS: The clinical stage was IA in 1 patient, IB in 2 patients, IIA in 3 patients, and IIB in 1 patient. Definitive CRT was completed in all patients. The median overall treatment time of radiotherapy was 44 days. The chemotherapy regimen included in dCRT was cisplatin and etoposide in 3 patients and carboplatin and etoposide in 4 patients. Acute adverse events of grade 3 or 4 were neutropenia 100%, thrombocytopenia 43%, febrile neutropenia 43%, and nausea 14%. There were no late grade 3 or 4 adverse events. The median survival time was 32 months. The complete response rate was 100%. The recurrence rate was 43%. The median survival of the 4 patients without recurrence was 56 months. CONCLUSIONS: Definitive CRT with cisplatin and etoposide or carboplatin and etoposide is a feasible treatment for the resectable SCNEC-E, and long-term survival can be achieved in some patients.

Lymph Node Progression and Optimized Node Dissection of Middle Thoracic Esophageal Squamous Cell Carcinoma in the Latest Therapeutic Surgical Strategy.

PURPOSE: The aim of this study is to elucidate the optimized lymph node dissection range in middle thoracic (Mt) esophageal squamous cell carcinoma (ESCC) requiring surgery. PATIENTS AND METHODS: We retrospectively analyzed 165 ESCC patients who underwent surgery with curative intent between 2009 and 2016, including 99 (60%) with MtESCC. Preoperative chemotherapy was administered in more than 80% of cStage II/III MtESCC patients. The rates of pathological and potential metastasis (representing recurrences) to lymph nodes and prognosis (median follow-up 52 months) were clarified. Lymph node dissection efficacy was assessed by calculating the efficacy index (EI) for each lymph node. RESULTS: No. 2R had the highest rate of metastasis, with frequencies of 13/38/46% in cStage I/II/III, respectively, with the highest EI in MtESCC. Recurrences were seen in about 2-10% in the regional (nos. 1, 2L, 4R, and 10) and extraregional lymph nodes (paraaortic lymph node). The EI of lymph nodes was found to exhibit the highest score of 15 for no. 2R, followed by 11.5 for no. 17. The 5-year overall survival (OS) in MtESCC patients who underwent no. 2R lymph node dissection was 73.8%, while those who did not undergo no. 2R dissection did never reach 5-year OS (P = 0.002). CONCLUSIONS: Meticulous lymph node dissection of no. 2R is the most important for long-term survival, and mandatory with the highest priority in MtESCC.

Comprehensive Exploration to Identify Predictive DNA Markers of ΔNp63/SOX2 in Drug Resistance in Human Esophageal Squamous Cell Carcinoma.

BACKGROUND: OBP-801 is a novel histone deacetylase inhibitor being developed as an anticancer drug. In this study, we explored genes to predict drug resistance in human cancer. METHODS: OBP-801 resistance was assessed in 37 strains of human cancer cell lines. Expression microarrays harboring 54,675 genes were used to focus on candidate genes, which were validated for both functional and clinical relevance in esophageal squamous cell carcinoma (ESCC). RESULTS: OBP-801 is sensitive to esophageal, gastric, and thyroid cancer, and resistant to some esophageal and colorectal cancers. We therefore used ESCC to explore genes. Comprehensive exploration focused on ΔNp63/SOX2, which were both genetically and epigenetically overexpressed in ESCC. Genomic amplifications of ΔNp63/SOX2 were tightly correlated each other (r = 0.81). Importantly, genomic amplification of ΔNp63/SOX2 in the resected tumors after neoadjuvant chemotherapy was significantly associated with histological grade of response (G1). Forced expression of either of these two genes did not induce each other, suggesting that their functional relevances were independent and showed robust drug resistance in OBP-801, as well as 5-fluorouracil. Furthermore, ΔNp63 could exert a potent oncogenic potential. RNA interference of ΔNp63 supported its oncological properties, as well as drug resistance. CONCLUSION: Comprehensive exploration of genes involved in anticancer drug residence could identify critical oncogenes of ΔNp63/SOX2 that would predict chemotherapy response in ESCC.

Safety and Feasibility of Robotic Distal Gastrectomy for Stage IA Gastric Cancer: A Phase II Trial.

BACKGROUND: Conventional laparoscopic and open distal gastrectomy procedures have inherent limitations such as restricted movement of straight forceps and tremor of the tip of the devices that can potentially be overcome using robotic distal gastrectomy (RDG). This single-institutional phase II trial aimed to evaluate the safety and feasibility of RDG with lymph node dissection for clinical stage IA gastric cancer. METHODS: The study included patients with clinical stage IA gastric cancer in the lower two-thirds of the stomach considered to be curatively resected via distal gastrectomy. The primary end point was the proportion of patients who developed intra-abdominal complications, requiring medical or interventional treatment. The planned sample size was 25, calculated based on an expected complication rate of 3% and a threshold complication rate of 15%, with a one-sided alpha of 10%, power of 70%. RESULTS: Overall postoperative complications rate was 16%. The proportion of patients who developed intra-abdominal complications, requiring treatment was 0% (90% confidence interval, 0-9.8%). No patient developed in-hospital adverse events of grade 3 or higher. The short-term clinical outcomes were as follows: the median duration of postoperative hospital stay was 7 d, and 10 patients (40.0%) had a body temperature of 38°C or higher during their hospital stay. CONCLUSIONS: This trial confirmed the safety of RDG with limitation by the restriction of dedicated surgeons. A phase III trial to confirm the superiority of RDG to conventional laparoscopic distal gastrectomy is warranted.

A phase II study of neoadjuvant chemotherapy with docetaxel, cisplatin, and S-1, followed by gastrectomy with D2 lymph node dissection for high-risk advanced gastric cancer: results of the KDOG1001 trial.

BACKGROUND: The prognosis of patients with gastric cancer with bulky node metastasis, linitis plastica (type 4), or large ulcero-invasive-type tumors (type 3) remains poor. We conducted a phase II study to evaluate the safety and efficacy of neoadjuvant chemotherapy with docetaxel, cisplatin, and S-1 (DCS) for establishing a new treatment modality that improves prognosis. METHODS: Patients received up to four 28-day cycles of DCS therapy (docetaxel at 40 mg/m2, cisplatin at 60 mg/m2 on day 1, and S-1 at 40 mg/m2 twice daily for 2 weeks) followed by gastrectomy with D2 nodal dissection. S-1 chemotherapy was administered for 1 year after surgical resection. The primary endpoint was the percentage of complete resections of the primary tumor with clear margins (R0 resection). The planned sample size was 40; this was calculated based on an expected R0 rate of 85% and a threshold R0 rate of 65%, with a one-sided alpha of 5% and a power of 90%. RESULTS: Between 2010 and 2017, 40 patients were enrolled. The R0 resection rate was 90%. The most common grade 3 or 4 adverse events during DCS therapy were leukocytopenia (27.5%), neutropenia (55.0%), and hyponatremia (22.5%). The most common grade 3 or 4 surgical morbidity was pancreatic fistula (12.5%); mortality was 0%. The pathological response rate was 57.5% with a grade 3 histological response rate of 8%. CONCLUSIONS: Neoadjuvant chemotherapy with DCS was feasible and showed a sufficient R0 resection rate. A future study with a sufficient follow-up period should confirm survival outcomes.

Comparison of double-flap and OrVil techniques of laparoscopy-assisted proximal gastrectomy in preventing gastroesophageal reflux: a retrospective cohort study.

BACKGROUND: Laparoscopy-assisted proximal gastrectomy (LAPG) with esophagogastrostomy using the double-flap technique has been reported to rarely cause gastroesophageal reflux. However, quantitative evaluation of the reflux has hardly been performed. The aim of this study was to clarify the superiority of the double-flap technique of LAPG with esophagogastrostomy compared with the OrVil technique in terms of preventing gastroesophageal reflux. METHODS: A total of 40 and 51 patients who underwent LAPG with esophagogastrostomy using the double-flap and OrVil techniques, respectively, for upper one-third gastric cancer were included in this study. Of these, 22 and 13 patients in the double-flap and OrVil groups, respectively, consented to undergo a 24-h impedance-pH monitoring test at 3 months postoperatively. Postoperative complications, including gastroesophageal reflux and anastomotic stricture, were assessed retrospectively. RESULTS: No significant differences were observed in the patients' background between both groups, except for a higher D1+ dissection rate observed in double-flap group than in the OrVil group (93% vs 25%, P < 0.001). Operative time was significantly longer in the double-flap group than in the OrVil group (353 min vs 280 min, P < 0.001). All reflux % time was significantly lower in the double-flap group than in the OrVil group (1.29% vs 2.62%, P = 0.043). On the other hand, the proportion of anastomotic stricture requiring endoscopic balloon dilatation was lower in the double-flap group than in the OrVil group but without statistical significance (18% vs 27%; P = 0.32). CONCLUSIONS: Despite its longer operative time and still relatively high anastomotic stricture rate, the double-flap technique would be better than the OrVil technique in terms of preventing gastroesophageal reflux in patients who underwent LAPG with esophagogastrostomy.