CD244+ polymorphonuclear myeloid­derived suppressor cells reflect the status of peritoneal dissemination in a colon cancer mouse model.

Despite the recent development of chemotherapeutic agents, the prognosis of colorectal cancer (CRC) patients with peritoneal dissemination (PD) remains poor. The tumor immune microenvironment (TIME) has drawn attention as a key contributing factor of tumor progression. Of TIME components, myeloid­derived suppressor cells (MDSCs) are considered to play a responsible role in the immunosuppressive characteristics of the TIME. MDSCs are classified into two major subsets: Monocytic MDSCs (M­MDSCs) and polymorphonuclear MDSCs (PMN­MDSCs). Therefore, we hypothesize that MDSCs would play important roles in the PD­relevant TIME and PD progression. To address this hypothesis, we established PD mouse models. As the PD nodules consisted scarcely of immune cells, we focused on the peritoneal cavity, but not PD nodule, to evaluate the PD­relevant TIME. As a result, intraperitoneal PMN­MDSCs were found to be substantially increased in association with PD progression. Based on these results, we phenotypically and functionally verified the usefulness of CD244 for identifying PMN­MDSCs. In addition, the concentrations of interleukin (IL)­6 and granulocyte­colony stimulating factor (G­CSF) were significantly increased in the peritoneal cavity, both of which were produced by the tumors and thought to contribute to the increases in the PMN­MDSCs. In vivo depletion of the PMN­MDSCs by anti­Ly6G monoclonal antibody (mAb) significantly inhibited the PD progression and reverted CD4+ and CD8+ T cells in the peritoneal cavity and the peripheral blood. Collectively, these results suggest that the targeted therapy for PMN­MDSCs would provide not only new therapeutic value but also a novel strategy to synergize with T­cell­based immunotherapy for CRC­derived PD.

Neoadjuvant Chemotherapy Increases PD-L1 Expression and CD8+ Tumor-infiltrating Lymphocytes in Esophageal Squamous Cell Carcinoma.

BACKGROUND/AIM: The aim of this study was to investigate PD-L1 expression and its association with prognosis in esophageal squamous cell carcinoma (ESCC) before and after neoadjuvant chemotherapy (5-fluorouracil and cisplatin, NAC-FP). PATIENTS AND METHODS: Using a database of 69 ESCC patients, we analyzed PD-L1 expression on tumor cells (TCs) and immune cells (ICs), as well as the density of CD8+ tumor-infiltrating lymphocytes (TILs) in pretreatment biopsy specimens-versus-surgical specimens after resection. We determined the prognostic significance of these factors. RESULTS: The fraction of ESCC containing ICs expressing PD-L1 and having a high CD8+ TIL density was significantly increased after neoadjuvant treatment. However, PD-L1 expression on TCs or ICs, and CD8+ TIL density, was not significantly associated with patient survival in ESCC patients. CONCLUSION: NAC-FP induced PD-L1 expression on ICs and CD8+ TILs in ESCC patients. This finding suggests that PD-1/PD-L1 blockade could be combined with NAC-FP to treat ESCC patients.

Application of iNKT Cell-targeted Active Immunotherapy in Cancer Treatment.

In tumor immunity, invariant natural killer T (iNKT) cells play a pivotal role as a link between the innate and adaptive immune systems. With a precisely regulated activation mechanism, iNKT cells have the ability to respond quickly to antigenic stimulation and rapidly produce cytokines and chemokines, and subsequently an effective antitumor immune response. The development of iNKT cell-targeted active immunotherapy enables, not only an antitumor immune response through innate and acquired immunity, but also the conversion of an immunosuppressive into an immunogenic microenvironment. This review is focused on the activation mechanism and the role of iNKT cells after therapeutic active immunization. The therapeutic strategy targeting iNKT cells is expected to be applied to clinical practice in combination with surgery and chemotherapy.

Immunosuppression Induced by Perioperative Peritonitis Promotes Lung Metastasis.

BACKGROUND/AIM: Perioperative intra-abdominal infection has been reported as a risk factor for metastasis. The aim of this study was to investigate the mechanism by which peritonitis induces immunosuppression in the lung, which in turn promotes lung metastasis. MATERIALS AND METHODS: C57BL/6 mice were intravenously administered B16F10 melanoma cells to induce lung metastasis and subsequently subjected to cecal ligation and puncture (CLP) to induce peritonitis or sham surgery. The number of lung metastatic nodules was evaluated. Cell fractions in lungs and serum cytokines after CLP were investigated. RESULTS: CLP mice showed an increased number of lung metastases compared to sham-treated mice. The fraction and number of natural killer (NK) cells in lungs of CLP mice were significantly reduced in early post-CLP phase. Myeloid-derived suppressor cells (MDSCs) in lungs were significantly decreased in CLP mice. Serum IL-6 and TNF levels were significantly elevated in CLP mice. CONCLUSION: Peritonitis promoted lung metastasis in a murine model, which may be attributable to the impact of NK cells and MDSCs in the lungs.

Incidence and predictive factors of lung cancer in patients with idiopathic pulmonary fibrosis.

The incidence and risk factors of lung cancer in patients with idiopathic pulmonary fibrosis (IPF) have been poorly investigated. We conducted a retrospective study of 632 patients with IPF to assess the incidence and risk factors of lung cancer development. Seventy patients developed lung cancer over a median follow-up period of 3.8 years. The incidence density of lung cancer development was 25.2 cases per 1000 person-years. The most frequent type was squamous cell carcinoma (30%), the majority developed lung cancer in the peripheral lung (82.9%) and adjacent to usual interstitial pneumonia (75.7%). In a multivariate Cox regression hazard model, pack-years of smoking ≥35 and coexisting emphysema were associated with lung cancer development. The 1-, 3- and 5-year all-cause mortality rates after lung cancer diagnosis were 53.5%, 78.6% and 92.9%, respectively. The incidence density of lung cancer is high in IPF patients and occurs more frequently in patients with smoking history of pack-years of smoking ≥35 and with coexisting emphysema. The majority of lung cancers develop adjacent to usual interstitial pneumonia. Knowledge of these factors may help direct efforts for early detection of lung cancer and disease management.

Frequency of Myeloid-derived Suppressor Cells in the Peripheral Blood Reflects the Status of Tumor Recurrence.

BACKGROUND: Malignant tumors inhibit antitumor immune responses, which are driven by T-regulatory cells or myeloid-derived suppressor cells (MDSCs). Since MDSCs are involved in invasion, migration, and metastasis of tumor cells, we hypothesized that MDSCs are also involved in tumor recurrence after surgical resection. MATERIALS AND METHODS: C57BL/6 mice were subcutaneously inoculated with B16F10 melanoma cells in the right flank. In some experiments, established tumors were surgically resected. Peripheral blood was drawn over time, and immune cells and cytokines were evaluated using flow cytometry. RESULTS: MDSCs and relevant pro-inflammatory cytokines increased in the peripheral blood of tumor-bearing mice. Moreover, the frequency of MDSCs rapidly increased in mice with tumor recurrence. CONCLUSION: The frequency of MDSCs in the peripheral blood of tumor-bearing mice reflects the status of tumor progression as well as tumor recurrence. Continuous monitoring of MDSCs in the peripheral blood might be a useful indicator of tumor recurrence.

Simple and reliable method for tumor localization during totally laparoscopic gastrectomy: intraoperative laparoscopic ultrasonography combined with tattooing.

We have developed a new method to localize a tumor during totally laparoscopic gastrectomy that uses intraoperative laparoscopic ultrasonography combined with preoperative clipping and tattooing. One or 2 days before the surgery, endoscopic clipping was performed just proximal to the tumor, followed by tattooing with India ink at the clipping site. Examination by intraoperative laparoscopic ultrasonography was performed at the tattooed site to detect the clips. The resection line of the stomach was determined with use of the detected clips as a marker of the proximal margin of the tumor. This method was attempted in 14 patients who underwent totally laparoscopic gastrectomy, and the clips were successfully identified in all patients. The clips were visualized as several layers of a hyperechoic bar, which was termed a "ladder sign." The mean time from insertion of the laparoscopic probe to identification of the clips was 2 min. The ladder sign is an important finding in this method.

Case Series of Pulmonary Tumor Embolism and Intravascular Lymphoma: Evaluation of the Usefulness of Pulmonary Microvascular Cytology.

Pulmonary tumor embolism (PTE) and intravascular lymphoma cause rapidly progressive deterioration and an antemortem diagnosis is difficult. The usefulness of pulmonary microvascular cytology (PMC) in the diagnosis of these disorders has been reported in sporadic case reports. We retrospectively evaluated the records of 7 patients with tumor cells in the pulmonary microvasculature (4 with PTE and 3 with malignant lymphoma) who underwent pulmonary microvascular cytology. Two of the 4 patients with PTE and 2 of the 3 patients with malignant lymphoma (all 3 had intravascular metastasis) had positive PMC results. These findings suggested that PMC may be useful in the diagnosis of these disorders.

The Long-term Clinical Course of Chronic Eosinophilic Pneumonia.

Objective The long-term clinical course and prognosis of patients with chronic eosinophilic pneumonia (CEP) including factors predictive of the relapse of CEP have not been fully investigated. The aim of the present study was to investigate these issues. Methods We retrospectively investigated the rate of relapse and prognosis in 73 patients diagnosed as having CEP. Results Systemic corticosteroid therapy was administered at a prednisolone dose of 29.4±7.6 mg/day. During a median follow-up period of 1,939 days, 27 patients suffered from relapse of CEP. Two patients developed steroid-induced diabetes mellitus, and 1 patient developed pulmonary nontuberculous mycobacteriosis. Five patients died; however, none died of CEP. A history of smoking was the only independent negative risk factor for relapse of CEP [hazard ratio, 0.37 (0.14-0.98)]. Conclusion Patients with CEP frequently relapse. During the follow-up, metabolic and infectious complications under prolonged corticosteroid therapy are problematic. A history of smoking was a negative factor for predicting the risk of CEP relapse.

Pulmonary Nontuberculous Mycobacteriosis and Chronic Lower Respiratory Tract Infections in Patients with Allergic Bronchopulmonary Mycosis without Cystic Fibrosis.

Objective The frequency of pulmonary nontuberculous mycobacteriosis (pNTM), chronic lower respiratory tract infections (cLRTIs), and pneumonia in patients with allergic bronchopulmonary mycosis (ABPM) without cystic fibrosis has not yet been fully investigated. Methods We retrospectively analyzed 42 patients with ABPM focusing on the frequency of pNTM and cLRTIs, acute exacerbation of cLRTIs, and pneumonia. Results During a median follow-up period of 2,299 days (range, 118-6,138 days), 7 patients developed pNTM (mainly Mycobacterium avium complex), and 21 patients developed cLRTI (mostly from Staphylococcus aureus followed by Pseudomonas aeruginosa). Twelve patients developed 21 episodes of acute exacerbation of cLRTIs, and 4 patients developed pneumonia. Conclusion Patients with ABPM can have concomitant NTM infection and, not uncommonly, cLRTI, and they can also sometimes develop pneumonia or an acute exacerbation of cLRTI.

Combined Allergic Bronchopulmonary Aspergillosis and Eosinophilic Granulomatosis with Polyangiitis: Three Cases and a Review of the Literature.

Previous reports of combined allergic bronchopulmonary mycosis (ABPM) and eosinophilic granulomatosis with polyangiitis (EGPA) are limited; however, among 41 cases of ABPM and 18 cases of EGPA treated at our hospital, we experienced three cases of combined ABPM and EGPA. In two of these cases, the diagnosis of EGPA preceded that of ABPM, however, one of the two cases had already shown findings suggestive of ABPM, such as mucous plugs and central bronchiectasis, at the time of the diagnosis of EGPA. In six previously reported cases of combined ABPM and EGPA, ABPM preceded EGPA in four cases. In the other two cases in which EGPA was diagnosed before or simultaneously with ABPM, findings suggestive of ABPM had been detected when EGPA was diagnosed, which suggests that sensitization to fungi resulting in ABPM may play an important role in the development of EGPA. Careful attention should therefore be paid to the possibility that these diseases may coexist during the course of either disease.

Asbestos exposure increases the incidence of histologically confirmed usual interstitial pneumonia.

AIMS: We hypothesized that asbestos exposure increases the incidence of macroscopically visible and histologically confirmed usual interstitial pneumonia (histological UIP). METHODS AND RESULTS: We retrospectively examined 1718 cases (1202 males; mean age 66.7 years) who underwent lobectomy for resection of pleuropulmonary tumours. Objective markers for asbestos exposure included: the presence of malignant pleural mesothelioma, the presence of pleural plaques (PPs) and asbestos bodies in the histological specimen. Risk factors for histological UIP were examined. Two separate groups were studied: 183 with asbestos exposure, and 239 with histological UIP. The 183 cases with asbestos exposure had higher rates of positive occupational history and histological UIP (31%) than the remaining 1535. Among the asbestos-exposed group, small numbers of asbestos bodies were found in histological specimens of 21 cases of histological UIP. PPs and asbestos bodies were more frequent in the 239 patients with histological UIP than in the remaining 1479 UIP-negative patients. Multivariate analysis showed that asbestos exposure, especially positivity for asbestos bodies, that does not meet the current criteria for asbestosis increases the risk of histological UIP (P < 0.0001). CONCLUSIONS: Asbestos exposure causes asbestosis and increases the incidence of histological UIP.

Risk Factors for Pneumonia and the Effect of the Pneumococcal Vaccine in Patients With Chronic Airflow Obstruction.

Background: To evaluate the risk factors for pneumonia and the efficacy of the pneumococcal polysaccharide vaccine (PPV) in patients with chronic airflow obstruction. Methods: We retrospectively studied the risk factors for pneumonia in 820 consecutive patients with chronic obstructive pulmonary disease (COPD) (n=509) and patients with asthma-COPD overlap syndrome (ACOS) (n=311). The effects of asthma, age, smoking history, chronic sputum, use of inhaled corticosteroids, percent predicted forced vital capacity (%FVC), percent predicted forced expiratory volume in 1 second (%FEV1), body mass index (BMI), computed tomography (CT)-diagnosed emphysema, and the pneumococcal vaccination on the frequency of pneumonia were assessed. Results: There was no difference in the frequency of pneumonia in patients with COPD and those with ACOS. In a univariate analysis, age (p= 0.031), %FVC (p< 0.001), %FEV1 (p < 0.001), BMI (p = 0.003), the presence of emphysema (p < 0.001) and a history of vaccination with the PPV (p = 0.034) were associated with the frequency of pneumonia. A multivariate analysis identified low BMI, the presence of emphysema and the absence of a pneumococcal vaccination as independent risk factors. The combination index of these factors, the BOVE index, which is calculated from low BMI (<22 kg/m2), low %FEV1 (<60%), vaccination history and emphysema was associated with the overall frequency of pneumonia. Conclusions:The index of multidimensional risk factors is useful to predict the frequency of pneumonia in patients with chronic airflow obstruction. The pneumococcal vaccination was associated with significantly lower incidence of pneumonia.

Retrospective study of the predictors of mortality and radiographic deterioration in 782 patients with nodular/bronchiectatic Mycobacterium avium complex lung disease.

OBJECTIVES: Some patients with nodular/bronchiectatic Mycobacterium avium complex lung disease (NB MAC-LD) deteriorate and die. The main aim of the study is to evaluate the prognostic factors and radiographic outcomes in patients with NB MAC-LD. SETTING: Retrospective single-centre review. PARTICIPANTS: 782 HIV-negative patients with NB MAC-LD treated at our institution in Japan. PRIMARY AND SECONDARY OUTCOME MEASURES: All-cause and MAC-LD progression mortality rates and the prognostic factors, and radiographic deterioration rates and the prognostic factors. RESULTS: Mean age was 68.1 years, and median follow-up period was 4.3 years. Death from any cause and progression of MAC lung disease (MAC-LD) occurred in 130 (16.6%), and 19 (2.4%) patients, respectively. All-cause and MAC-LD progression 10-year mortality rates were 27.4% and 4.8%, respectively. In 536 patients with MAC-LD who were followed-up for more than 1 year, radiographic deterioration occurred in 221 (41.2%) patients and median time-to-radiographic deterioration was 9 years. A multivariate Cox proportional hazard model showed male sex, older age, body mass index <18.5 kg/m(2), absence of bloody sputum, hypoalbuminaemia and erythrocyte sedimentation rate >40 mm/h to be negative prognostic factors for all-cause mortality, and the presence of idiopathic pulmonary fibrosis, haemoglobin <11.3 mg/dL, C reactive protein >1.0 mg/dL and the presence of cavity to be negative prognostic factors for radiographic deterioration. CONCLUSIONS: Only 2.4% of patients with NB MAC-LD died from MAC-LD progression. As clinical trials testing the effectiveness of drug therapy in patients with NB MAC-LD are being designed and implemented, the primary end point could be time-to-radiographic deterioration, and trial patients need to be stratified according to these prognostic factors before randomisation.

A Simple and Reliable Method for Intracorporeal Circular-Stapled Esophagojejunostomy Using a Hand-Sewn Over-and-Over Suture Technique in Laparoscopic Total Gastrectomy.

BACKGROUND: The controversy regarding laparoscopic total gastrectomy (LTG) is mainly due to the difficulty associated with esophagojejunostomy during this procedure. Although several techniques have so far been reported to overcome this issue,1 (-) 4 a reliable technique has not yet been established. We developed intracorporeal esophagojejunostomy using a circular stapler in LTG with a hand-sewn over-and-over suture technique, and have shown its favorable outcomes compared with those of conventional open surgery.5 This technique is presented in the video. METHODS: After transection of the esophagus, an over-and-over suture with a 2-0 monofilament is placed counterclockwise from the right to the left side of the cut end in an outside-to-inside direction, and then from the left to the right side in an inside-to-outside direction. After insertion of the anvil head into the esophagus, it was fixed by ligation of the thread. Finally, intracorporeal esophagojejunal anastomosis was performed using a circular stapler. RESULTS: In LTG, reconstruction using this method was performed for 23 consecutive patients with gastric cancer. There were no serious intraoperative complications or need for conversion to open surgery. Anastomotic leakage and stenosis occurred in one case each, respectively. The mean time for fixation of the anvil to the esophagus was 15 min for the last 12 consecutive patients. CONCLUSIONS: This method is simple and feasible, and the advantage of this technique is the elimination of the backhand stroke throughout the suturing procedure.

A Three-Step Method for Laparoscopic Mobilization of the Splenic Flexure.

BACKGROUND: Splenic flexure mobilization (SFM) is sometimes required for secure and tension-free anastomosis during laparoscopic colorectal surgery. Although several approaches have been used for laparoscopic SFM,1 it is still considered complicated and troublesome because of the lack of a standardized technique. We propose a three-step method for laparoscopic SFM, aimed at providing a simplified and standardized method, which is presented in the video. METHOD: First, the mesocolon of the transverse and descending colon is dissected from the retroperitoneal tissue using a medial approach. The appropriate plane for dissection can be recognized just beneath the inferior mesenteric vein, and the gauze should be placed in the dissected space. Second, the transverse colon and transverse mesocolon are detached from the pancreas and spleen by means of an anterior approach. The lesser sac is opened, and the attachment to the pancreas or spleen is cut using the inserted gauze as a landmark. Third, the lateral attachment of the descending colon to the left abdominal wall is dissected cranially or caudally. RESULTS: Using this method, we performed laparoscopic SFM for 13 patients with colorectal cancer with no conversion to another approach or to open surgery. No intraoperative complications were reported, including bleeding from the spleen and injury of the pancreas. The mean time for SFM was 55 min. CONCLUSIONS: We consider this three-step method as being useful, and it might help the standardization of laparoscopic SFM.

Progressive diffuse pulmonary interstitial opacities due to complications of pulmonary tumor emboli: an autopsy case report.

A 76-year-old man complaining of exertional dyspnea was admitted to our hospital. Chest computed tomography revealed bilateral diffuse ground-glass opacities and small nodules. A transbronchial lung biopsy revealed tumor cell emboli in the pulmonary arteries. The patient was diagnosed with gastric adenocarcinoma using an endoscopic stomach biopsy; however, the interstitial opacities progressively worsened and he died of acute respiratory failure. An autopsy revealed extensive pulmonary tumor embolisms (PTE) with associated ischemic damages, e.g., infarctions, alveolar wall thickening with cuboidal metaplasia, hemorrhage, and diffuse alveolar damage. The ground-glass opacities in the chest computed tomography findings appear to correlate with the pathological ischemic changes associated with PTE.

Surgical outcomes of intracorporeal circular-stapled esophagojejunostomy using modified over-and-over suture technique in laparoscopic total gastrectomy.

BACKGROUND: Esophagojejunostomy in laparoscopic total gastrectomy (LTG) is a technically demanding procedure. Although several methods have been reported to date, none is considered consistently reliable. We developed a simple method for intracorporeal circular-stapled esophagojejunostomy using a modified over-and-over suture technique. The surgical outcomes of our technique were evaluated in comparison with those of open total gastrectomy (OTG). METHODS: From April 2012 to August 2014, reconstruction using this method in LTG was performed for 21 consecutive patients with gastric cancer (LTG group). Their surgical outcomes were compared with those of 27 patients with gastric cancer who underwent OTG without splenectomy (OTG group) between January 2011 and April 2014. RESULTS: Estimated blood loss was significantly lower, and the postoperative hospital stay was significantly shorter in the LTG group than in the OTG group. The operating time and the number of harvested lymph nodes were similar between the two groups. The incidence of overall complications did not differ significantly between the two groups. Anastomotic leakage developed in one of the 21 patients in the LTG group and in two of the 27 patients in the OTG group. Anastomotic stenosis was observed in one patient in the LTG group. CONCLUSIONS: We consider this method as simple and feasible for most laparoscopic surgeons with basic laparoscopic suturing skills. This method might help LTG to become an accepted standard surgical option for treatment of patients with gastric cancer.

Cranially approached radical lymph node dissection around the middle colic vessels in laparoscopic colon cancer surgery.

PURPOSE: Laparoscopic lymph node (LN) dissection around the middle colic vessels is technically demanding, thus raising controversy regarding the role of laparoscopic surgery for transverse colon cancer. We herein describe a cranial approach method to perform radical LN dissection around the middle colic vessels. The key characteristic of this approach is early division of middle colic vessels prior to mobilization of the colon. METHODS: From April 2010 to September 2013, 27 patients with colon cancer received laparoscopic LN dissection around the middle colic vessels using this cranial approach. Their surgical and short-term outcomes were reviewed. RESULTS: The mean number of harvested LNs was 29 (range, 6-50). The mean operative time and intraoperative blood loss were 274 min (range, 160-362 min) and 42 mL (range, 3-247 mL), respectively. There were no serious intraoperative complications or conversions to open surgery. There were two patients with stage 0, 7 with stage I, 12 with stage II, and 6 with stage III. No recurrent case was observed with a median follow-up period of 30 months (range, 9-48 months). CONCLUSIONS: We consider this approach feasible and useful for radical LN dissection around the middle colic vessels during laparoscopic colon cancer surgery.