Molecular and clinicopathological features of KIT/PDGFRA wild-type gastrointestinal stromal tumors.

Approximately 10% of gastrointestinal stromal tumors (GISTs) harbor reportedly no KIT and PDGFRA mutations (wild-type GISTs). The clinicopathological features and oncologic outcomes of wild-type GISTs based on molecular profiles are unknown. We recruited 35 wild-type GIST patients from the two registry studies of high-risk GISTs between 2012 and 2015 and primary GISTs between 2003 and 2014. Molecular profiling of wild-type GISTs was performed by targeted next-generation sequencing (NGS) using formalin-fixed paraffin-embedded tumor samples. Among 35 wild-type GISTs, targeted NGS analysis detected NF1, SDH, or BRAF mutation: 16 NF1-GISTs with various NF1 mutations, 12 SDH-GISTs (4 with SDHA mutations, 4 with SDHB mutations, and 4 with SDHB-negative staining), and 5 BRAF-GISTs with the V600E mutation. Two GISTs showed no mutations based on our targeted NGS analysis. Additional gene mutations were infrequent in primary wild-type GISTs and found in TP53, CREBBP, CDKN2A, and CHEK2. Most NF1-GISTs were located in the small intestine (N = 12; 75%) and showed spindle cell features (N = 15; 94%) and multiple tumors (N = 6, 38%) with modest proliferation activities. In contrast, SDH-GISTs were predominantly found in the stomach (N = 11; 92%), exhibiting epithelioid cell (N = 6; 50%) and multiple (N = 6, 50%) features. The overall survival of patients with SDH-GISTs appeared to be better than that of BRAF-GISTs (p = 0.0107) or NF1-GISTs (p = 0.0754), respectively. In conclusion, major molecular changes in wild-type GISTs include NF1, SDH, and BRAF. NF1-GISTs involved multifocal spindle cell tumors in the small intestine. SDH-GISTs occurred in young patients and were multifocal in the stomach and clinically indolent.

Cutibacterium acnes-derived extracellular vesicles promote tumor growth in renal cell carcinoma.

Bacterial flora are present in various parts of the human body, including the intestine, and are thought to be involved in the etiology of various diseases such as multiple sclerosis, intestinal diseases, cancer, and uterine diseases. In recent years, the presence of bacterial 16S rRNA genes has been revealed in blood, which was previously thought to be a sterile environment, and characteristic blood microbiomes have been detected in various diseases. However, the mechanism and the origin of the bacterial information are unknown. In this study, we performed 16S rRNA metagenomic analysis of bacterial DNA in serum extracellular vesicles from five healthy donors and seven patients with renal cell carcinoma and detected Cutibacterium acnes DNA as a characteristic bacterial DNA in the serum extracellular vesicles of patients with renal cell carcinoma. In addition, C. acnes DNA was significantly reduced in postoperative serum extracellular vesicles from patients with renal cell carcinoma compared with that in preoperative serum extracellular vesicles from these patients and was also detected in tumor tissue and extracellular vesicles from tumor tissue-associated microbiota, suggesting an association between C. acnes extracellular vesicles and renal cell carcinoma. C. acnes extracellular vesicles were taken up by renal carcinoma cells to enhance their proliferative potential. C. acnes extracellular vesicles also exhibited tumor-promoting activity in a mouse model of renal cancer allografts with enhanced angiogenesis. These results suggest that extracellular vesicles released by C. acnes localized in renal cell carcinoma tissues act in a tumor-promoting manner.

Serum NY-ESO-1 antibody as a predictive biomarker for postoperative recurrence of gastric cancer: a multicenter prospective observational study.

BACKGROUND: No reliable marker has been identified to predict postoperative recurrence of gastric cancer. We designed a clinical trial to investigate the utility of serum NY-ESO-1 antibody responses as a predictive marker for postoperative recurrence in gastric cancer. METHODS: A multicenter prospective study was conducted between 2012 and 2021. Patients with resectable cT3-4 gastric cancer were included. Postoperative NY-ESO-1 and p53 antibody responses were serially evaluated every 3 months for 1 year in patients with positive preoperative antibody responses. The recurrence rate was assessed by the positivity of antibody responses at 3 and 12 months postoperatively. RESULTS: Among 1001 patients, preoperative NY-ESO-1 and p53 antibody responses were positive in 12.6% and 18.1% of patients, respectively. NY-ESO-1 antibody responses became negative postoperatively in non-recurrent patients (negativity rates; 45% and 78% at 3 and 12 months, respectively), but remained positive in recurrent patients (negativity rates; 9% and 8%, respectively). p53 antibody responses remained positive in non-recurrent patients. In multivariate analysis, NY-ESO-1 antibody positivity at 3 months (P < 0.03) and 12 months (P < 0.001) were independent prognostic factors for a shorter recurrence-free interval. CONCLUSIONS: Serum NY-ESO-1 antibodies may be a useful predictive marker for postoperative recurrence in gastric cancer. CLINICAL TRIAL REGISTRATION: UMIN000007925.

Long-Term Effects of Oral Nutritional Supplements After Gastrectomy for Gastric Cancer: A Survival Analysis from a Multicenter, Open-Label, Randomized Controlled Trial.

BACKGROUND: Weight loss (WL) after gastrectomy for gastric cancer is associated with both decreased compliance with adjuvant chemotherapy and impaired survival. This study examined the effects of administering oral nutritional supplements (ONS) for 3 months after gastrectomy in terms of compliance with adjuvant chemotherapy and survival outcomes. METHODS: This large-scale, multicenter, open-label, randomized controlled trial enrolled 1,003 gastric cancer patients undergoing curative gastrectomy. Patients were assigned to the control group (n = 503) or ONS group (n = 500). In the ONS group, 400 kcal/day of ONS was recommended in addition to a regular diet for 3 months after gastrectomy. Compliance with adjuvant chemotherapy and survival outcomes were compared between the two groups. RESULTS: Compared with the control group, the ONS group showed significantly decreased WL at 3 months after gastrectomy (8.6 ± 6.1 vs. 7.2 ± 5.7%, respectively, P = 0.0004). The control and ONS groups did not differ regarding the induction rate of adjuvant chemotherapy (84.9 vs. 82.8%, respectively, P = 0.614) or the continuation rate at 3 months postoperatively (75.3 vs. 76.6%, respectively, P = 0.809). Oral nutritional supplements for 3 months showed no survival benefit; the 3- and 5-year overall survival (OS) rates were 91.3% and 87.6% in the control group and 89.6% and 86.4% in the ONS group, respectively, indicating no significant difference (P = 0.548). Subgroup analysis could not detect a population in which ONS administration increased OS. CONCLUSIONS: Administration of ONS for 3 months after gastrectomy was not associated with increased compliance with adjuvant chemotherapy or with improved prognosis.

In situ analysis of CCR8+ regulatory T cells in lung cancer: suppression of GzmB+ CD8+ T cells and prognostic marker implications.

BACKGROUND: CCR8-expressing regulatory T cells (Tregs) are selectively localized within tumors and have gained attention as potent suppressors of anti-tumor immunity. This study focused on CCR8+ Tregs and their interaction with CD8+ T cells in the tumor microenvironment of human lung cancer. We evaluated their spatial distribution impact on CD8+ T cell effector function, specifically granzyme B (GzmB) expression, and clinical outcomes. METHODS: A total of 81 patients with lung squamous cell carcinoma (LSCC) who underwent radical surgical resection without preoperative treatment were enrolled. Histological analyses were performed, utilizing an automated image analysis system for double-stained immunohistochemistry assays of CCR8/Foxp3 and GzmB/CD8. We investigated the association of CCR8+ Tregs and GzmB+ CD8+ T cells in tumor tissues and further evaluated the prognostic impact of their distribution profiles. RESULTS: Histological evaluation using the region of interest (ROI) protocol showed that GzmB expression levels in CD8+ T cells were decreased in areas with high infiltration of CCR8+ Tregs, suggesting a suppressive effect of CCR8+ Tregs on T cell cytotoxicity in the local tumor microenvironment. Analysis of the association with clinical outcomes showed that patients with more CCR8+ Tregs and lower GzmB expression, represented by a low GzmB/CCR8 ratio, had worse progression-free survival. CONCLUSIONS: Our data suggest that local CCR8+ Treg accumulation is associated with reduced CD8+ T cell cytotoxic activity and poor prognosis in LSCC patients, highlighting the biological role and clinical significance of CCR8+ Tregs in the tumor microenvironment. The GzmB/CCR8 ratio may be a useful prognostic factor for future clinical applications in LSCC.

FBXW7 regulates the sensitivity of imatinib in gastrointestinal stromal tumors by targeting MCL1.

BACKGROUND: Imatinib contributes to improving prognosis of high-risk or unresectable gastrointestinal stromal tumors (GISTs). As therapeutic efficacy is limited by imatinib resistance and toxicity, the exploration of predictive markers of imatinib therapeutic efficacy that enables patients to utilize more effective therapeutic strategies remains urgent. METHODS: The correlation between FBXW7 and imatinib resistance via FBXW7-MCL1 axis was evaluated in vitro and in vivo experiments. The significance of FBXW7 as a predictor of imatinib treatment efficacy was examined in 140 high-risk patients with GISTs. RESULTS: The ability of FBXW7 to predict therapeutic efficacy of adjuvant imatinib in high-risk GIST patients was determined through 5-year recurrence-free survival (RFS) rates analysis and multivariate analysis. FBXW7 affects imatinib sensitivity by regulating apoptosis in GIST-T1 cells. FBXW7 targets MCL1 to regulate apoptosis. MCL1 involves in the regulation of imatinib sensitivity through inhibiting apoptosis in GIST-T1 cells. FBXW7 regulates imatinib sensitivity by down-regulating MCL1 to enhance imatinib-induced apoptosis in vitro. FBXW7 regulates imatinib sensitivity of GIST cells by targeting MCL1 to predict efficacy of imatinib treatment in vivo. CONCLUSIONS: FBXW7 regulates imatinib sensitivity by inhibiting MCL1 to enhance imatinib-induced apoptosis in GIST, and predicts efficacy of imatinib treatment in high-risk GIST patients treated with imatinib.

Association between fibrosis around the tumor and postoperative infectious complication in patients with esophageal cancer who underwent preoperative therapy.

BACKGROUND: Multidisciplinary treatment combining chemotherapy, chemo radiation therapy (CRT), and surgery has been utilized for advanced esophageal cancer. However, preoperative treatment could cause postoperative inflammation and complications. We hypothesized that fibrosis surrounding tumor tissue caused by preoperative treatment could induce postoperative systemic inflammation and influence postoperative complications. METHODS: Surgical specimens from patients with thoracic esophageal cancer who underwent preoperative CRT (38 cases) or chemotherapy (77 cases) and those who received no preoperative treatment (49 cases) were evaluated to measure the fibrotic area adjacent to the tumor (10 mm from the tumor edge) by applying Azan staining. Pleural effusion and peripheral blood serum interleukin-6 levels were analyzed to evaluate local and systemic postoperative inflammation in 37 patients. RESULTS: The fibrotic areas around the tumors were significantly larger in patients who underwent preoperative CRT than in patients who underwent chemotherapy (p < 0.001) or who had received no preoperative therapy (p < 0.001). Infectious complications were higher in patients who underwent preoperative CRT than chemotherapy (p = 0.047) or surgery alone (p < 0.001). The patients with larger fibrotic areas had more infectious complications (p = 0.028). Multivariate analysis showed that both a large fibrotic area and preoperative CRT were correlated with infectious complications, but not significantly. Pleural effusion interleukin-6 was significantly higher in patients who underwent preoperative CRT than in patients who received no preoperative therapy (p = 0.013). CONCLUSIONS: A large fibrotic peritumoral esophageal tissue area after preoperative treatment could cause postoperative inflammatory response and infectious complications.

Indications for neoadjuvant chemotherapy in older patients undergoing esophagectomy for esophageal cancer.

PURPOSE: To investigate the indications for neoadjuvant chemotherapy (NAC) in esophageal cancer patients aged 75 years or older. METHODS: We analyzed data, retrospectively, from 155 patients over 75 years old, who underwent esophagectomy for esophageal cancer between 2010 and 2020. Forty-one patients underwent upfront surgery (US group) and 114 were treated with NAC followed by surgery (NAC group). We compared the patient backgrounds and perioperative outcomes including prognosis, between the two groups. RESULTS: The NAC group patients were significantly younger and had significantly more advanced clinical stage disease than the US group patients. The incidence of postoperative complications was similar in the two groups. Patients with a good pathological response to NAC had a significantly better prognosis than those with a poor response and those in the US group. Among patients with a performance status (PS) of 0, the 5-year OS rate was 56.5% in the NAC group and 38.1% in the US group (HR = 0.63, 95% CI 0.35-1.12). Among those with a PS of 1-2, the 5-year OS rates were 28.1% and 57.1%, respectively (HR = 1.69, 95% CI 0.99-2.89; P = 0.037 for interaction). CONCLUSIONS: NAC did not improve the postoperative prognosis of older esophageal cancer patients with a PS of 1 or higher.

Pancreas-left gastric artery angle predicts difficulty of suprapancreatic lymph node dissection in gastrectomy for gastric cancer: a cross-sectional study.

PURPOSE: Suprapancreatic lymph node dissection is one of the most challenging procedures performed in the treatment of gastric cancer. This study aimed to investigate whether the pancreas-left gastric artery angle (PLA) can be used to predict the difficulty of the procedure. METHODS: This was a single-center cross-sectional study. Before gastrectomy, the patients were classified according to the size of the PLA into the small PLA (s-PLA; < 30°) and large PLA (l-PLA; ≥ 30°) groups in a surgeon-blinded manner. After gastrectomy, a surgeon evaluated suprapancreatic lymph node dissection as hard, normal, or easy to perform. RESULTS: Seventy-three patients were enrolled in the study. Surgeons evaluated lymph node dissection as hard in 43.8 and 8.7% of patients in the s-PLA and l-PLA groups, respectively (p = 0.002). The time taken for suprapancreatic lymph node dissection was also significantly longer in the s-PLA group than in the l-PLA group (p = 0.040). In patients who underwent laparoscopic gastrectomy, the time for node dissection in the s-PLA group was also significantly longer than that in the s-PLA group (p = 0.021), while there was no difference in those who underwent robotic surgery (p = 0.815). CONCLUSION: PLA is useful for predicting the degree of difficulty of suprapancreatic lymph node dissection during gastrectomy for gastric cancer.

The role of anterior gastropexy in elderly Japanese hiatal hernia patients.

PURPOSE: As Japanese society ages, the number of surgeries performed in elderly patients with hiatal hernia (HH) is increasing. In this study, we examined the feasibility, safety, and potential effectiveness of the addition of anterior gastropexy to hiatoplasty with or without mesh repair and/or fundoplication in elderly Japanese HH patients. METHODS: We retrospectively evaluated 39 patients who underwent laparoscopic HH repair between 2010 and 2021. We divided them into 2 groups according to age: the "younger" group (< 75 years old, n = 21), and the "older" group (≥ 75 years old, n = 18). The patient characteristics, intraoperative data, and postoperative results were collected. RESULTS: The median ages were 68 and 82 years old in the younger and older groups, respectively, and the female ratio was similar between the groups (younger vs. older: 67% vs. 78%, p = 0.44). The older group had more type III/IV HH cases than the younger group (19% vs. 83%, p < 0.001). The operation time was longer in the older group than in the younger group, but there was no significant difference in blood loss, perioperative complications, or postoperative length of stay between the groups. The older group had significantly more cases of anterior gastropexy (0% vs. 78%, p < 0.001) and less fundoplication (100% vs. 67%, p = 0.004) than the younger group. There was no significant difference in HH recurrence between the groups (5% vs. 11%, p = 0.46). CONCLUSIONS: The addition of anterior gastropexy to other procedures is feasible, safe, and potentially effective in elderly Japanese patients with HH.

A new scope warmer/cleaner for laparoscopic surgery: a disposable hot pack.

BACKGROUND: Fogging and staining of a laparoscope lens negatively impact surgical visualization. We hypothesized that the disposable hot pack could not only warm but also clean laparoscopes. Hence, this study verified and developed the disposable hot pack with anti-fogging and cleaning function. MATERIAL AND METHODS: The laparoscope was inserted into a swine abdominal cavity for five minutes. Then, the laparoscopic tip was heated with 65 °C saline or the folded disposable hot pack with nonwoven fabric coated surfactant for ten seconds (n = 15). Also, a laparoscopic tip with dirt was wiped with the prototype or conventional gauze for 10 s (n = 10). The dirt, fogging, and temperature of the laparoscopic tip were respectively evaluated after the laparoscope was inserted into the abdominal cavity. RESULTS: The laparoscopic tip temperature five minutes after insertion into the abdominal cavity was similar (31.1 °C vs 31.2 °C, p = 0.748) and there was no fogging in both methods. The conventional gauze had significantly less temperature of the laparoscopic tip after cleaning and higher fogging occurrence than the prototype (29.5 °C vs 34.0 °C, p < 0.001, 30% vs 0%, p = 0.030, respectively), although there was no dirt left after both methods. CONCLUSION: The disposable hot pack has a strong potential as an anti-fogging and cleaning device for use during laparoscopic surgery.

Innovative device for surgical wound irrigation: a preclinical testing and pilot clinical validation study.

INTRODUCTION: Surgical site infection (SSI) poses a substantial postoperative challenge, affecting patient recovery and healthcare costs. While surgical wound irrigation is pivotal in SSI reduction, consensus on the optimal method remains elusive. We developed a novel device for surgical wound irrigation and conducted preclinical and clinical evaluations to evaluate its efficacy and safety. METHODS: Two preclinical experiments using swine were performed. In the washability test, two contaminated wound model were established, and the cleansing rate between the device and the conventional method were compared. In the contamination test, the irrigation procedure with a fluorescent solution assessed the surrounding contamination of drapes. Subsequently, a clinical trial involving patients undergoing abdominal surgery was conducted. RESULTS: The washability test demonstrated significantly higher cleansing rates with the device method (86.4% and 82.5%) compared to the conventional method (65.2% and 65.1%) in two contamination models. The contamination test revealed a smaller contaminated region with the device method than the conventional method. In the clinical trial involving 17 abdominal surgery cases, no superficial SSIs or adverse events related to device use were observed. CONCLUSIONS: Our newly developed device exhibits potential for achieving more effective and safe SSI control compared to conventional wound irrigation.

Combination of pimitespib (TAS-116) with sunitinib is an effective therapy for imatinib-resistant gastrointestinal stromal tumors.

Despite the effectiveness of imatinib, most gastrointestinal stromal tumors (GISTs) develop resistance to the treatment, mainly due to the reactivation of KIT tyrosine kinase activity. Sunitinib, which inhibits the phosphorylation of KIT and vascular endothelial growth factor (VEGF) receptor, has been established as second-line therapy for GISTs. The recently-developed heat shock protein 90 (HSP90) inhibitor pimitespib (PIM; TAS-116) demonstrated clinical benefits in some clinical trials; however, the effects were limited. The aim of our study was therefore to clarify the effectiveness and mechanism of the combination of PIM with sunitinib for imatinib-resistant GISTs. We evaluated the efficacy and mechanism of the combination of PIM with sunitinib against imatinib-resistant GIST using imatinib-resistant GIST cell lines and murine xenograft models. In vitro analysis demonstrated that PIM and sunitinib combination therapy strongly inhibited growth and induced apoptosis in imatinib-resistant GIST cell lines by inhibiting KIT signaling and decreasing auto-phosphorylated KIT in the Golgi apparatus. In addition, PIM and sunitinib combination therapy enhanced antitumor responses in the murine xenograft models compared to individual therapies. Further analysis of the xenograft models showed that the combination therapy not only downregulated the KIT signaling pathway but also decreased the tumor microvessel density. Furthermore, we found that PIM suppressed VEGF expression in GIST cells by suppressing protein kinase D2 and hypoxia-inducible factor-1 alpha, which are both HSP90 client proteins. In conclusion, the combination of PIM and sunitinib is effective against imatinib-resistant GIST via the downregulation of KIT signaling and angiogenic signaling pathways.

Risk stratification of oesophageal squamous cell carcinoma using change in total lesion glycolysis and number of PET-positive lymph nodes.

BACKGROUND: The efficacy of neoadjuvant chemotherapy (NACT) correlates with patient survival in oesophageal squamous cell carcinoma (OSCC), but optimal evaluation of the treatment response based on PET-CT parameters has not been established. METHODS: We analysed 226 OSCC patients who underwent PET-CT before and after NACT followed by surgery. We assessed SUVmax, metabolic tumour volume (MTV), and total lesion glycolysis (TLG) for the primary tumour and the number of PET-positive lymph nodes before and after NACT to predict patient survival. RESULTS: In a stepwise analysis, we defined 60%, 80%, and 80% as the optimal cut-off values for SUVmax, MTV, and TLG reduction, respectively, to distinguish responders and non-responders to NACT. In the ROC analysis, the TLG reduction rate was the best predictor of recurrence among PET-CT parameters. The TLG responders achieved significantly more favourable prognoses than non-responders (2-year progression-free survival [PFS] rate: 64.1% vs. 38.5%; P = 0.0001). TLG reduction rate (HR 2.58; 95% CI 1.16-5.73) and the number of PET-positive lymph nodes after NACT (HR 1.79; 95% CI 1.04-3.08) were significant independent prognostic factors. CONCLUSIONS: TLG reduction is the best predictor of prognosis. Preoperative PET-CT evaluation of both the primary tumour and lymph nodes could accurately stratify risk in OSCC patients.

Density and maturity of peritumoral tertiary lymphoid structures in oesophageal squamous cell carcinoma predicts patient survival and response to immune checkpoint inhibitors.

BACKGROUND: Tertiary lymphoid structures (TLSs) are ectopic lymphoid aggregates in non-lymphoid tissues, which are associated with improved prognosis in some cancer types. This study aimed to investigate the clinical significance of TLSs in oesophageal cancer (EC). METHODS: In a series of 316 EC surgical specimens from two different institutes, we evaluated the density and maturity of peritumoral TLSs using haematoxylin/eosin, immunohistochemistry, and multiplex immunofluorescence staining. We analysed the association between TLSs and clinicopathological parameters. The clinical significance of TLSs was further evaluated in a different cohort of 34 patients with recurrent EC treated with anti-PD-1 antibody. RESULTS: Tumours with high TLS density predominantly consisted of matured TLSs. High TLS density was significantly associated with less advanced tumour stage, absence of lymphatic/vascular invasion, better serum nutrition parameters (neutrophils count, albumin, neutrophil-to-lymphocyte ratio, and prognostic nutritional index), and prolonged survival. This survival trend was more remarkable in cases with matured TLSs, which represented an increased population of CD138+ plasma cells. In the second EC cohort, TLS density predicted the clinical response to anti-PD-1 antibody and patient survival. CONCLUSION: The density and maturity of peritumoral TLSs are useful parameters for predicting long-term survival and response to anti-PD-1 antibody treatment in EC patients.

Immunoscore Signatures in Surgical Specimens and Tumor-Infiltrating Lymphocytes in Pretreatment Biopsy Predict Treatment Efficacy and Survival in Esophageal Cancer.

OBJECTIVES: Tumor-infiltrating lymphocytes (TILs) have long been recognized as playing an important role in tumor immune microenvironment. Lately, the Immunoscore (IS) has been proposed as a new method of quantifying the number of TILs in association with patient survival in several cancer types. METHODS: In 300 preoperatively untreated esophageal cancer (EC) patients who underwent curative resection at two different institutes, immunohistochemical staining using CD3 and CD8 antibodies was performed to evaluate IS, as objectively scored by auto-counted TILs in the tumor core and invasive margin. In addition, in pre-neoadjuvant chemotherapy (pre-NAC) endoscopic biopsies of a different cohort of 146 EC patients who received NAC, CD3, and CD8 were immunostained to evaluate TIL density. RESULTS: In all cases, the IS-high (score 3-4) group tended to have better survival [5-year overall survival (OS) of the IS-high vs low group: 77.6 vs 65.8%, P = 0.0722] than the IS-low (score 1-2) group. This trend was more remarkable in cStage II-IV patients (70.2 vs 54.5%, P = 0.0208) and multivariate analysis of OS further identified IS (hazard ratio 2.07, P = 0.0043) to be an independent prognostic variable. In preNAC biopsies, NAC-responders had higher densities than non-responders of both CD3 + ( P = 0.0106) and CD8 + cells ( P = 0.0729) and, particularly CD3 + cell density was found to be an independent prognostic factor (hazard ratio 1.75, P = 0.0169). CONCLUSIONS: The IS signature in surgical specimens and TIL density in preNAC- biopsies could be predictive markers of clinical outcomes in EC patients.

The tissue-resident marker CD103 on peripheral blood T cells predicts responses to anti-PD-1 therapy in gastric cancer.

BACKGROUND: Immune checkpoint inhibitors (ICIs) have revolutionized cancer treatment. Since clinical benefits are limited to a subset of patients, we aimed to identify peripheral blood biomarkers that predict the efficacy of the anti-programmed cell death protein 1 (PD-1) antibody (nivolumab) in patients with gastric cancer. METHODS: We collected peripheral blood samples from gastric cancer patients (n = 29) before and after treatment with nivolumab and investigated the relationship between the frequency of surface or intracellular markers among nivolumab-binding PD-1+CD8+ T cells and treatment responses using multicolor flow cytometry. The tumors, lymph nodes, and peripheral blood of gastric cancer patients who underwent gastrectomy following nivolumab treatment were collected, and nivolumab-binding PD-1+CD8+ T cells in these tissue samples were characterized. RESULTS: Patients with a high frequency of CD103 among PD-1+CD8+ T cells in peripheral blood 2 weeks after the start of treatment had significantly better progression-free survival than the low group (P = 0.032). This CD103+PD-1+CD8+ T cell population mainly consisted of central memory T cells, showing the high expression of Ki-67 and few cytotoxic granules. In contrast, effector memory T cells were more frequently observed among CD103+PD-1+CD8+ T cells in tumors, which implied a change in the differentiated status of central memory T cells in lymph nodes and peripheral blood to effector memory T cells in tumors during the treatment with ICIs. CONCLUSIONS: A high frequency of CD103 among PD-1+CD8+ T cells 2 weeks after nivolumab treatment in patients with advanced gastric cancer may be a useful biomarker for predicting the efficacy of anti-PD-1 therapy.

Clinical Significance of Intramural Metastasis as an Independent Prognostic Factor in Esophageal Squamous Cell Carcinoma.

BACKGROUND: Although intramural metastasis (IM) in esophageal cancer is considered a poor prognostic factor, there are only limited reports detailing its clinicopathologic characteristics and prognostic impact. PATIENTS AND METHODS: We retrospectively included patients with esophageal squamous cell carcinoma (ESCC) with esophagectomy at our institution between 2010 and 2016. We compared patients with intramural metastases (IMs) (IM group) versus those without IMs (non-IM group) to clarify the clinical significance of intramural metastasis in ESCC. RESULTS: A total of 23 (3.9%) out of all 597 patients were identified to have IM. The IMs were located on the cranial side in 13 (56.5%) and caudal side in 10 (43.5%) of the primary tumor, with two multiple cases. The IM group, compared with the non-IM group, was associated with higher percentage of cN-positive (91.3 versus 67.9%, P = 0.02), pN-positive (82.6 versus 55.9%, P = 0.04), and pM(lym)-positive (30.4 versus 12.5%, P = 0.02) cases. Five-year recurrence-free survival (RFS) was significantly worse in the IM group than the non-IM group (14.9 versus 55.0 %, P < 0.001). Multivariable analysis of recurrence-free survival identified pT (HR 1.74, 95% CI 1.36-2.23, P < 0.001), pN (HR 2.11, 95% CI 1.60-2.78, P < 0.001), histological classification (HR 1.68, 95% CI 1.21-2.35, P = 0.002), and pM(LYM) (HR 1.64, 95% CI 1.64-2.95, P < 0.001), along with presence of IM (HR 2.24, 95% CI 1.37-3.64, P < 0.001) to be independent prognostic factors. Lymphatic (65.2 versus 24.9%, P < 0.001) and hepatic (26.1 versus 6.8%, P = 0.005) recurrences were significantly more common in the IM group than in the non-IM group. CONCLUSIONS: IM was shown to be associated with dismal survival after surgery. A treatment strategy emphasizing more intensive systemic control should be considered for patients with ESCC with IM.

Preoperative Comprehensive Geriatric Assessment Predicts Postoperative Risk in Older Patients with Esophageal Cancer.

BACKGROUND: Preoperative risk assessment is important in older patients because they often have comorbidities and impaired organ function. We performed preoperative comprehensive geriatric assessment (CGA) for older patients with esophageal cancer. PATIENTS AND METHODS: A total of 217 patients over 75 years old who underwent esophagectomy for thoracic esophageal cancer were analyzed. The CGA was performed preoperatively and included the Mini-Mental State Examination (MMSE), Geriatric Depression Score (GDS), vitality index, Barthel index, and instrumental activities of daily living (IADL). We defined the robust group as patients with normal function on every instrument, and the pre-frail and frail groups as those with functional impairment on one instrument or two or more instruments, respectively. We assessed how the CGA correlated with postoperative complications and prognosis. RESULTS: Of the 217 patients, 86 (39.6%) were in the robust group, 68 (31.3%) in the pre-frail group, and 63 (29.0%) in the frail group. Postoperative pneumonia (P = 0.026) and anastomotic leakage (P = 0.032) were significantly more common in the frail group. The frail group had a significantly longer postoperative hospitalization period (P = 0.016) and significantly lower rate of discharge to home (P = 0.016). Overall survival (OS) was significantly worse in the frail group (5-year overall survival rate, frail group versus others, 37.8% versus 52.0%, P = 0.046), but it was not significant on multivariate analysis. CONCLUSIONS: The preoperative CGA in older patients with esophageal cancer was associated with risk of postoperative complications.

Gas leakages from gastrointestinal endoscopy system-its visualization and semi-quantification utilizing schlieren optical system in the swine models.

BACKGROUND AND AIMS: With the global epidemic of SARS-CoV-2, there has been a growing concern regarding the risk of aerosol exposure to healthcare workers and patients during medical/surgical interventions. The Schlieren device is capable of visualizing fine gas-flows by using refractive index differences in the medium. We aimed to reveal the existence of gas leakage from gastro-intestinal endoscopy system by utilizing Schlieren device and to clarify the factors which relates to the amount of gas leakage. METHODS: The experiments were performed on the excised swine stomach while maintaining a constant pressure environment in the stomach. The System Schlieren (SS100,KatoKoken) was used to visualize possible gas leakages from forceps plugs of endoscopy. We attempted to semi-quantify the leakage by referring to the image of the gas from the forceps plug and by measuring the initial velocity and diffusion area of the leakage. RESULTS: Regardless of the type of forceps plugs, a certain amount of leakage was detected during both insertion and removal of forceps. The initial velocity and the diffusion area of the leakage increased with the increase in intragastric pressure. Semi-quantitative comparison showed that there was a difference in the amount of gas leakage among various forceps plugs. Furthermore, the amount of gas leakage was significantly greater in the forceps plugs that were used repeatedly. CONCLUSION: It was possible to visualize gas leakages from the gastrointestinal endoscope system using the Schlieren optical device. Avoiding too high intragastric pressure and not using deteriorated plugs may reduce the risk of aerosol exposure.