Key nodal stations for predicting splenic hilar nodal metastasis in upper advanced gastric cancer without invasion of the greater curvature.

Background: Standard surgery for upper advanced gastric cancer without invasion of the greater curvature (UGC-GC) is spleen-preserving D2 total gastrectomy without dissection of the splenic-hilar nodes (#10). However, some patients with nodal metastasis to #10 survive more than 5 years due to nodal dissection of #10. If nodal metastasis to #10 is predictable based on the positivity of other nodes dissected by the current standard surgery without #10 nodal dissection, physicians may be able to consider #10 dissection. Methods: This study retrospectively reviewed data from the National Cancer Center Hospital in Japan between 2000 and 2012. We selected cases that met the following criteria: (1) D2 or more total gastrectomy with splenectomy, (2) UGC-GC, and (3) histological type is gastric adenocarcinoma. We performed univariate and multivariate analyses concerning lymph node stations associated with #10 metastasis. Results: A total of 366 patients were examined. A multivariate analysis revealed that #10 metastasis was associated with positivity of the nodes along the short gastric arteries (#4sa) and distal nodes along the splenic artery (#11d) (#4sa: p = 0.003, #11d: p = 0.016). When either key node was positive, the metastatic rate of #10 was 24.4%, and the therapeutic value index was 13.3. Conclusions: #4sa and #11d were key lymph nodes predicting #10 nodal metastasis in UGC-GC. When these key nodes are positive on computed tomography before surgery or according to a rapid pathological examination during surgery, dissection of #10 should be considered even if upper advanced tumors are not invading the greater curvature.

Impact of D2 Total Gastrectomy Including Splenectomy for Scirrhous Gastric Cancer in the Era of Effective Adjuvant Chemotherapy.

BACKGROUND: Total gastrectomy with D2 dissection including splenectomy (TGS) is usually selected for locally resectable scirrhous gastric cancer (SGC), which was established in the era of surgery alone. However, it remains unclear whether TGS for SGC is justified in the era of effective adjuvant chemotherapy. METHODS: This study included 112 SGC patients, consisting of 60 cases treated between January 2000 and December 2006 (Former group), and 52 cases treated between January 2007 and December 2016 (Latter group). We collected clinicopathological data and then examined the survival and the therapeutic value indexes. RESULTS: The background characteristics were well-balanced, except for sex and physical status. The Latter group might be characterized by frequent female (P = 0.037) and poorer physical status (P = 0.048). Adjuvant chemotherapy was administered to 86.5% of the Latter group and was 11.7% of the Former group (P < 0.001). The 5-year-overall survival rate of the Latter group was 58.7% (95% confidence interval: 43.5-71.1), seems better than that of the Former group (44.5%; 95% confidence interval 31.7-56.6) (hazard ratio = 0.758, P = 0.291). Improvement of the index from the Former group was observed in the Latter group at almost all stations. The ratio of the index between two groups was 1.42 at the D1 station and 1.67 at the D2 station. Index of splenic hilar node ranked similarly high in both groups. CONCLUSION: The therapeutic value index was improved in almost all nodal stations by S-1 adjuvant chemotherapy, especially in D2 nodes. TGS would be more important for locally resectable SGC in the era of effective adjuvant chemotherapy.

Clinical characteristics and management of primary retroperitoneal sarcoma: A literature review.

Retroperitoneal sarcoma (RPS) is a rare tumor classified into many histological types. It is also often detected only after it has grown to a considerable size and requires extensive resection of the surrounding organs, making it difficult to offer optimal patient-tailored management. Evidence supporting specific treatment modalities for RPS is insufficient, owing to its rarity. The Japanese clinical practice guidelines for RPS were published in December 2021, with the aim of accumulating existing evidence and indicating the optimal practice for RPS. These guidelines provide important clinical questions (CQs) concerning the diagnosis and treatment of RPS. This review, with a particular focus on primary RPS, attempts to introduce clinical problems in the diagnosis and treatment of RPS and to assess those problems along with the CQs in the guidelines. According to these guidelines, although chemotherapy and radiotherapy are expected to have therapeutic effects, the level of evidence to support these treatments is not very high at present. Accordingly, complete resection of the tumor is the first and only option for managing primary RPS. However, as with other tumors, the demand for multidisciplinary treatment for RPS is increasing. These guidelines will undoubtedly represent a milestone in clinical practice in relation to RPS in the future, and further evidence is expected to be accumulated based on the CQs that have been proposed.

A discrimination model by machine learning to avoid gastrectomy for early gastric cancer.

Aim: Gastrectomy is recommended for patients with early gastric cancer (EGC) because the possibility of lymph node metastasis (LNM) cannot be completely denied. The aim of this study was to develop a discrimination model to select patients who do not require surgery using machine learning. Methods: Data from 382 patients who received gastrectomy for gastric cancer and who were diagnosed with pT1b were extracted for developing a discrimination model. For the validation of this discrimination model, data from 140 consecutive patients who underwent endoscopic resection followed by gastrectomy, with a diagnosis of pT1b EGC, were extracted. We applied XGBoost to develop a discrimination model for clinical and pathological variables. The performance of the discrimination model was evaluated based on the number of cases classified as true negatives for LNM, with no false negatives for LNM allowed. Results: Lymph node metastasis was observed in 95 patients (25%) in the development cohort and 11 patients (8%) in the validation cohort. The discrimination model was developed to identify 27 (7%) patients with no indications for additional surgery due to the prediction of an LNM-negative status with no false negatives. In the validation cohort, 13 (9%) patients were identified as having no indications for additional surgery and no patients with LNM were classified into this group. Conclusion: The discrimination model using XGBoost algorithms could select patients with no risk of LNM from patients with pT1b EGC. This discrimination model was considered promising for clinical decision-making in relation to patients with EGC.

Acceleration of sarcopenia in elderly patients who develop asymptomatic pneumonia shadow within one year after surgery for early gastric cancer.

BACKGROUND: Although early gastric cancer is curable with local treatment, the overall survival in elderly patients did not reach 80% at five years after surgery. The major cause of death in elderly patients with early gastric cancer is not cancer itself but is related to postoperative sarcopenia. Elderly patients frequently develop postoperative asymptomatic pneumonia shadow, which is associated with a poor prognosis. However, why asymptomatic pneumonia shadow worsens the prognosis remains unclear. We investigated whether sarcopenia is accelerated in patients who developed asymptomatic pneumonia shadow. METHODS: We retrospectively examined patients of > 75 years of age who underwent R0 gastrectomy for gastric cancer and were diagnosed with T1 disease at National Cancer Center Hospital between 2005 and 2012. The diagnosis of asymptomatic pneumonia shadow was defined by diagnostic findings of pneumonia (consolidation type, reticular type, and nodular type) which were newly observed on chest computed tomography performed one year after surgery in comparison to preoperative computed tomography. Postoperative muscle loss was assessed by a computed tomography-based analysis using the L3 skeletal muscle index before and two years after surgery and the rate of decrease was calculated. Patients were classified into two groups according to the rate of decrease (cut-off value: 10%). RESULTS: Of the 3412 patients who underwent gastrectomy in our hospital during the study period, 142 were included in this study. Asymptomatic pneumonia shadow was found in 26 patients (18%). Patients who developed asymptomatic pneumonia shadow showed a significantly greater loss of muscle volume in comparison to patients who did not develop asymptomatic pneumonia shadow. In the multivariate analysis, total gastrectomy and asymptomatic pneumonia shadow were the independent risk factors for severe muscle loss. However, there was no significant difference in prognosis between the two groups. CONCLUSIONS: Sarcopenia was accelerated in elderly patients who developed asymptomatic pneumonia shadow after surgery for early gastric cancer. However, the poor prognosis in these patients may not be related to accelerated sarcopenia.

Clinical and endoscopic features of metachronous gastric cancer with possible lymph node metastasis after endoscopic submucosal dissection and Helicobacter pylori eradication.

BACKGROUND: Several studies have reported the metachronous gastric cancers (MGCs) with possible lymph node metastasis (LNM) after endoscopic submucosal dissection (ESD) and Helicobacter pylori (H. pylori) eradication in which a curative ESD had not been achieved. There have been no published reports of evaluations of the features of patients with MGC with possible LNM after ESD and H. pylori eradication. METHODS: We identified 264 patients with 369 MGCs after H. pylori eradication among the 4354 patients with 5059 early gastric cancers (EGCs) who underwent ESD between 1999 and 2017 and divided them into two groups: patients with MGCs with possible LNM (Group I) and patients with MGCs undergone curative ESD (Group II). We retrospectively compared the features of patients with MGCs and patients with EGCs at index ESD in the two groups. RESULT: Group I consisted of 20 patients with 21 MGCs, and Group II consisted of 244 patients with 348 MGCs. Group I lesions were significantly more common in the posterior wall than in the lesser curvature (odds ratio [OR] = 3.97; 95% confidence intervals [CI] 1.20-13.10). Development of Group I was significantly more common in patients with a body mass index (BMI) < 19.0 kg/m2 than in patients with a BMI ≥ 19.0 kg/m2 at index ESD (OR = 4.44; 95% CI 1.30-15.20). CONCLUSIONS: During surveillance endoscopy after gastric ESD and H. pylori eradication, the posterior wall should be carefully examined to detect MGCs early. Lower BMI may be associated with the development of MGCs with possible LNM.

Possible candidates for splenic hilar nodal dissection among patients with upper advanced gastric cancer without invasion of the greater curvature.

BACKGROUND: Spleen preserving D2 total gastrectomy without dissection of the splenic hilar nodes (#10) is a standard operation for upper advanced gastric cancer without invasion of the greater curvature (UGC-wGC). However, some patients with #10 metastasis have survived after splenectomy with dissection of #10. This study explored possible candidates for dissection of #10 among patients with UGC-wGC by examining the metastatic rate and the therapeutic index. METHODS: This study retrospectively reviewed data of patients treated in National Cancer Center Hospital (Japan) between 2000 and 2012. We applied the following inclusion criteria: (1) ≥ D2 total gastrectomy with splenectomy, (2) UGC-wGC, and (3) gastric adenocarcinoma histology. Univariate and multivariate analyses were performed to identify risk factors for #10 metastasis. RESULTS: A total of 366 patients were examined; #10 metastasis was observed in 4.4% (16/366). The multivariate analysis revealed that location (posterior vs. others, P = 0.025) and histology (undifferentiated vs. differentiated, P = 0.048) were significant factors for #10 metastasis among sex, age, tumor size, dominant circumferential location, macroscopic type, depth of invasion, and histology. The incidence of #10 metastasis was 14.9% (7/47) for tumors located on the posterior wall with undifferentiated type histology. The 5-year overall survival rate of these patients was 42.9%, and the therapeutic index was 6.38, which was the second highest value among the second-tier nodal stations. CONCLUSION: Even for upper advanced gastric cancer without invasion of the greater curvature, dissection of #10 could be justified for tumors located on the posterior wall with undifferentiated type histology.

Impact of D2 Gastrectomy for Locally Advanced Gastric Cancer in the Era of Effective Adjuvant Chemotherapy.

BACKGROUND: Gastrectomy with D2 dissection has been established as the standard procedure for locally advanced gastric cancer in the era of surgery alone. However, no consideration has been given to the efficacy of dissection in the era of effective adjuvant chemotherapy. METHODS: This study included 1298 advanced gastric cancer patients, consisting of 725 cases treated between January 2000 and December 2006 (Former group), and 573 cases treated between January 2007 and July 2015 (Latter group). Clinicopathological data were collected, survival and the therapeutic value index were determined. RESULTS: The background characteristics were well balanced, except for age, tumor location, and intraoperative blood loss. The Latter group showed the following characteristics: an older population (p < 0.001), a frequent upper location (p = 0.008), and less blood loss (p < 0.001). Adjuvant chemotherapy was administered to 75.2% of the Latter group and was 9.4% in the Former group. The 5-year overall survival rate of the Latter group was 75.7% (95% confidence interval: 71.7-79.1), significantly better than that of the Former group (70.0%, 95% confidence interval: 66.5-73.2) (p = 0.025). Improvement in the index from the Former group was observed in the Latter group at almost all stations. The ratio of the index between these two groups was 1.09 at the D1 station and 1.19 at the D2 station. CONCLUSION: The therapeutic value index was improved in all nodal stations by S-1 adjuvant chemotherapy, regardless of whether the D1 or D2 nodes were involved. D2 gastrectomy would be still important for locally advanced gastric cancer in the era of effective adjuvant chemotherapy.

[Gentle Method to Elevate Left Liver Lobe in Robot Assisted Gastrectomy].

Robot-assisted gastrectomy with the Davinci XiTM has been performed in our department since August 2019. This technique requires elevation of the left liver lobe. In order to prevent perioperative liver injury and expansion of postoperative subcutaneous emphysema, we use a silicone disc(HAKKO MEDICAL Co., Ltd.)and thread to elevate the liver. After docking the Davinci system, we move the needle as follows:(ⅰ). left side peritoneum near the left triangular ligament, (ⅱ). silicone rubber(, ⅲ). center of crus(, ⅳ). silicone rubber(, ⅴ). hepatic cirrus, and(ⅵ). right side peritoneum. Both ends of the thread are guided out of the abdominal cavity from both hepatic circumflex by end-close, forming a V-shape with the center of crus at the bottom, which provides a stable and effective view of the liver. Fifty-three cases were performed after introduction of this elevation technique. Median AST and ALT on postoperative day 1 were 37(14-1,556)IU/L and 30(10- 1,676)IU/L, respectively, although small subcutaneous emphysema confined to the anterior chest and upper abdominal wall was observed in 2 patients(3.8%). No cases of extensive subcutaneous emphysema involving the neck or extremities were observed. This elevation technique protects the liver and may reduce the incidence of postoperative subcutaneous emphysema.

Prognostic Impact of Long-term Postoperative Pneumonia in Elderly Patients with Early Gastric Cancer.

Background: Elderly patients with stage I gastric cancer, a disease that is curable by surgery, easily develop long-term postoperative pneumonia (LTPP) within two years after surgery despite showing no active symptoms. The present study assessed whether or not LTPP determines the later prognosis among elderly patients. Methods: We retrospectively examined patients >75 years old who underwent R0 gastrectomy for gastric cancer and were diagnosed with T1 disease at National Cancer Center Hospital between 2005 and 2012. LTPP was evaluated by chest computed tomography every year until two years after surgery. Results: Of the 3412 patients who underwent gastrectomy in our hospital during this period, 159 were included in this study. The elderly patients who developed LTPP had a worse prognosis than those who did not. Furthermore, their comorbidities and LTPP were significant independent risk factors for a poor prognosis. Patients who developed LTPP had a significantly higher risk of dying due to respiratory disease or cardiovascular disease than those without pneumonia. Conclusions: LTPP was significantly related to a poor survival and death from respiratory disease. To improve the prognosis, not only nutritional support but also exercise and rehabilitation program may be required for patients who develop LTPP within two years after surgery.

Long-term postoperative pneumonia in elderly patients with early gastric cancer.

BACKGROUND: Pneumonia is a major cause of death in the elderly population. Considering body weight loss, muscle loss, and reflux after gastrectomy, elderly patients are considered to be at very high risk for pneumonia, which could decrease overall survival because early gastric cancer is mostly curable only by surgery. We aimed to clarify the incidence of pneumonia in the long-term period after gastrectomy in elderly patients who were diagnosed with early gastric cancer and its risk factors. METHODS: We retrospectively examined patients of > 75 years of age who underwent R0 gastrectomy for gastric cancer and who were diagnosed with T1 disease at National Cancer Center Hospital between 2005 and 2012. Long-term postoperative pneumonia was diagnosed by chest computed tomography every year until 2 years after surgery. The presence of preoperative sarcopenia was assessed using preoperative L3 skeletal muscle index. RESULTS: 167 patients were included in this study. Long-term postoperative pneumonia was observed in 44 (26%) patients. Of the 44 people diagnosed with long-term postoperative pneumonia, 33 were diagnosed in the 1st year and 11 in the 2nd year. 117 patients (70%) were diagnosed with sarcopenia which was significantly frequently found in the patients who developed long-term postoperative pneumonia (91%) than those without (63%). Preoperative sarcopenia was the only independent risk factor in multivariate analysis. Type of gastrectomy was not a significant risk factor. CONCLUSIONS: Long-term postoperative pneumonia was frequently observed in the elderly patients. Preoperative sarcopenia was associated with long-term postoperative pneumonia in elderly patients who underwent curative surgery for gastric cancer. After gastrectomy, long-term special care would be required for elderly patients, especially with sarcopenia.

Suprapancreatic nodal dissection should not be uniformly selected in additional gastrectomy for the patients who diagnosed as pT1b gastric cancer by endoscopic resection.

BACKGROUND: Surgery for T1b gastric cancer requires suprapancreatic nodes (SPA nodes) and perigastric nodes (PG nodes), however, SPA nodal dissection can cause pancreatic complications. If endoscopic treatment followed by additional surgery is planned, it may be possible to predict SPA nodal metastasis by analyzing the pathological information of the primary tumor in addition to the clinical findings. METHODS: Patients who underwent D1+ or D2 and who were pathologically diagnosed with pT1b were retrospectively analyzed. The stations were divided into the nodes located at the perigastric area (PG nodes; #1-7) and the nodes located at the suprapancreatic area (SPA nodes; #8a-12a). The patients were classified into those with and without metastasis to the SPA nodes. Clinicopathological factors were investigated for their possible association with metastasis to the SPA nodes. RESULTS: A total of 2017 patients were examined in this study. Metastasis to the SPA nodes was observed in 80 patients (4%). In a multivariate analysis, undifferentiated histology, lower third, and lymphovascular invasion were independent risk factors for metastasis to the SPA nodes. The risk of metastasis to the SPA nodes was <2% in upper/middle tumors of differentiated type with no lymphovascular invasion and in lower tumors of undifferentiated type with no lymphovascular invasion. On the other hand, the risk of metastasis to the SPA nodes was >10% in lower tumors of undifferentiated type with lymphovascular invasion. CONCLUSION: SPA nodal metastasis can be predicted when endoscopic treatment is initially planned. SPA nodal dissection should not be uniformly selected for T1b gastric cancer.

Optimal surgery and lymph node metastasis of duodenal bulbar neuroendocrine neoplasms.

BACKGROUND: There is no consensus on the extent of nodal dissection for duodenal bulbar NENs (neuroendocrine neoplasms). MATERIALS AND METHODS: We constructed and analyzed a combined dataset consisting of the patients who received surgery in our hospital and the patients from the literature based on a systematic review. The incidence, risk factors and location of nodal metastases were examined. RESULTS: Fifty-nine cases including 11 cases managed at our hospital and 48 cases identified from the literature search were examined. Nodal metastasis was observed in 24 patients (40.7%). The 5-year overall survival rate was 100%, regardless of nodal metastasis. Risk factors for lymph node metastasis were tumor size ≥15 mm and muscularis propria or deeper invasion. Stomach-related lymph node metastasis was found in >20% of patients who were positive for at least one risk factor and 15.4% when patients were negative for both risk factors, while pancreas-related lymph node metastasis was observed in 45.5% of patients who were positive for both risk factors, 7.7% who were only positive for one risk factor, and 0% who were negative for both risk factors. CONCLUSIONS: Tumor size and depth of invasion would determine whether the optimal surgery for duodenal bulbar NENs is distal gastrectomy or pancreatico-duodenectomy.

Pathological complete response at the para-aortic nodes as a possible surrogate endpoint in gastric cancer surgery with para-aortic node dissection after neoadjuvant chemotherapy.

PURPOSE: Gastric cancer with para-aortic node (PAN) metastasis has a chance to be cured with multidisciplinary treatment of D2 and PAN dissection (PAND) following neoadjuvant chemotherapy (NAC), but its prognosis remains unsatisfactory. To establish a better multidisciplinary treatment, a better surrogate endpoint is needed. The present study focused on a pathological complete response at the PANs alone as a new surrogate endpoint and evaluated its prognostic value. METHODS: The study examined patients who received radical gastrectomy with D2 and PAND after NAC for gastric cancer with PAN metastasis from 2004 to 2015. The study compared five methods of evaluating the response to NAC: RECIST, clinical disappearance of PANs (cPAN), histological response of the primary tumor defined by Japanese Classification of Gastric Carcinoma (JCGC histological criteria) and Becker's criteria, and pathological disappearance of PANs (pPAN). The efficacy of these methods was compared using the hazard ratio (HR) for death between responders and non-responders. RESULTS: Thirty-two patients were analyzed. The respective HR and 5-year overall survival rates of responders and non-responders were 1.316 and 49.1% vs. 60.0% by RECIST, 1.106 and 52.9% vs. 52.5% by cPAN, 0.246 and 71.3% vs. 28.6% by JCGC histological criteria, 0.239 and 76.2% vs. 36.8% by Becker's criteria, and 0.074 and 81.0% vs. 0.0% by pPAN. CONCLUSIONS: A pathological complete response at the PANs had the lowest HR and clearly differentiated the survival, suggesting it might be a good surrogate endpoint for identifying future candidates for NAC in multidisciplinary treatment for gastric cancer with PAN metastasis.

Comparable genetic alteration profiles between gastric cancers with current and past Helicobacter pylori infection.

Gastric cancers can develop even after Helicobacter pylori (H. pylori) eradication in 0.2-2.9% cases per year. Since H. pylori is reported to directly activate or inactivate cancer-related pathways, molecular profiles of gastric cancers with current and past H. pylori infection may be different. Here, we aimed to analyze whether profiles of point mutation and gene amplification are different between the two groups. Current or past infection by H. pylori was determined by positive or negative amplification of H. pylori jhpr3 gene by PCR, and past infection was established by the presence of endoscopic atrophy. Among the 90 gastric cancers analyzed, 55 were with current infection, and 35 were with past infection. Target sequencing of 46 cancer-related genes revealed that 47 gastric cancers had 68 point mutations of 15 different genes, such as TP53 (36%), KRAS (4%), and PIK3CA (4%) and that gene amplification was present for ERBB2, KRAS, PIK3CA, and MET among the 26 genes assessed for copy number alterations. Gastric cancers with current and past infection had similar frequencies of TP53 mutations (38% and 31%, respectively; p = 0.652) and oncogene activation (20% and 29%, respectively; p = 0.444). Gastric cancers with current and past infection had comparable profiles of genetic alterations.

The prognostic impact of macroscopic serosal change on resectable advanced gastric cancer.

BACKGROUND: Advanced gastric cancer sometimes causes macroscopic serosal change (MSC) due to direct invasion or inflammation. However, the prognostic significance of MSC remains unclear. METHODS: A total of 1410 patients who had been diagnosed with deeper-than-pathological-T2 gastric cancer and undergone R0 gastrectomy with lymph node dissection at the National Cancer Center Hospital during January 2000 and December 2012 were restrospectively reviewed. RESULTS: MSC was not found in 108 of the 506 patients with pathological T4a (21.3%), whereas it was detected in 250 of the 904 patients with pathological T2-T3 (27.7%). The sensitivity, specificity and accuracy for diagnosing pathological serosa exposed (SE) by MSC were 78.7, 72.3 and 74.6%, respectively. The MSC-positive cases had a worse 5-year overall survival (OS) than the MSC-negative cases in pT3 (72.9% vs. 84.3%, p = 0.001), pT4a (56.2% vs. 73.4%, p = 0.001), pStageIIB (76.0% vs. 88.4%, p = 0.005), pStageIIIA (63.4% vs. 75.6%, p = 0.019), pStageIIIB (53.6% vs. 69.2%, p = 0.029) and pStage IIIC (27.6% vs. 50.0%, p = 0.062). A multivariate analysis showed that MSC was a significant independent predictor for the OS (hazard ratio [HR]: 1.587, 95%CI 1.209-2.083, p = 0.001) along with the tumor depth (HR: 7.742, 95%CI: 2.935-20.421, p < 0.001), nodal status (HR:5.783, 95% CI 3.985-8.391, p < 0.001) and age (HR:2.382, 95%CI: 1.918-2.957, p < 0.001). Peritoneal recurrence rates were higher in the MSC-positive cases than in the MSC-negative cases at each pT stage. CONCLUSIONS: In this study, the MSC was one of the independent prognostic factors in patients with resectable locally advanced gastric cancer.

Comparison of short-term outcomes between transthoracic and robot-assisted transmediastinal radical surgery for esophageal cancer: a prospective study.

BACKGROUND: The present study aimed to assess the lower invasiveness of robot-assisted transmediastinal radical esophagectomy by prospectively comparing this procedure with transthoracic esophagectomy in terms of perioperative outcomes, serum cytokine levels, and respiratory function after surgery for esophageal cancer. METHODS: Patients who underwent a robot-assisted transmediastinal esophagectomy or transthoracic esophagectomy between April 2015 and March 2017 were included. The perioperative outcomes, preoperative and postoperative serum IL-6, IL-8, and IL-10 levels, and respiratory function measured preoperatively and at 6 months postoperatively were compared in patients with a robot-assisted transmediastinal esophagectomy and those with a transthoracic esophagectomy. RESULTS: Sixty patients with esophageal cancer were enrolled. The transmediastinal esophagectomy group had a significantly lower incidence of postoperative pneumonia (p = 0.002) and a significantly shorter postoperative hospital stay (p < 0.0002). The serum IL-6 levels on postoperative days 1, 3, 5, and 7 were significantly lower in the transmediastinal esophagectomy group (p = 0.005, 0.0007, 0.022, 0.020, respectively). In the latter group, the serum IL-8 level was significantly lower immediately after surgery and on postoperative day 1 (p = 0.003, 0.001, respectively) while the serum IL-10 level was significantly lower immediately after surgery (p = 0.041). The reduction in vital capacity, percent vital capacity, forced vital capacity, and forced expiratory volume at 1.0 s 6 months after surgery was significantly greater in the transthoracic esophagectomy group (p < 0.0001 for all four measurements). CONCLUSIONS: Although further, large-scale studies are needed to confirm our findings, robot-assisted transmediastinal esophagectomy may confer short-term benefits in radical surgery for esophageal cancer. TRIAL REGISTRATION: This trial was registered in the UMIN Clinical Trial Registry ( UMIN000017565 14/05/2015).

Is lymph node dissection for neuroendocrine carcinoma of the stomach effective as it is for adenocarcinoma?

BACKGROUND: We evaluated the significance of lymph node dissection for gastric neuroendocrine carcinoma (NEC) by calculating the therapeutic value index for each station. METHODS: This study included 2164 advanced gastric cancer patients (common-type [Common-GC], n = 2125; and gastric NEC [NEC-GC], n = 39). Clinicopathological data were collected, and survival, type of recurrence, and the index for each type of gastrectomy were determined. RESULTS: NEC-GC was characterized by an older population (P = 0.009), upper tumor location (P = 0.021), frequent venous invasion (P < 0.001), and less neural invasion (P = 0.043). NEC-GC tended to be more frequent in men (P = 0.152), and to be associated with total gastrectomy (P = 0.177) and M1 cases (P = 0.167). The five-year overall survival rates of the Common-GC and NEC-GC groups were 73.8% (95% confidence interval: 71.8-75.6) and 54.7% (37.5-68.9), respectively (P = 0.016). Both groups showed similar index values in each station. Regarding the index of the peri-gastric nodal station (D1 station)/stations away from the stomach (D2 station), although the index of the D1 station was similar in the two groups (41.3 and 43.1), the index of the D2 station in the NEC-GC group was approximately half that of the Common-GC group (10.0 and 5.3). The total recurrence rates of the two groups were similar (P = 0.871). However, the rates of hematogenous and lymphatic recurrence tended to be higher in the NEC-GC group (P = 0.132 and P = 0.152). CONCLUSIONS: The therapeutic efficacy of the D1 station was similar in Common-GC and NEC-GC but that of the D2 station was worse in NEC-GC. Gastrectomy with D2 dissection would be less effective for NEC-GC.