Preoperative bacterial culture can predict severe pneumonia in patients receiving esophagectomy

Background: Postoperative pneumonia is one of the major complications after esophagectomy. The aim of this study was to determine whether bacterial cultures before esophagectomy could predict occurrence of postoperative pneumonia and help treatment strategies for postoperative pneumonia. Methods: Sixty-nine patients who underwent subtotal esophagectomy at Fukushima Medical University Hospital between January 2017 and May 2021 were included in this study. We collected sputum, oral, and/or nasopharyngeal swabs for bacterial culture preoperatively from all patients and from those who were suspected of postoperative pulmonary infections. We compared cultured pathogenic bacteria obtained preoperatively and postoperatively from patients who developed postoperative pneumonia, and investigated their association with incidence of postoperative pneumonia. Results: Postoperative pneumonia occurred in 22 of 69 patients (31%), including 13 cases of severe pneumonia with a Clavien-Dindo classification of grade IIIa or higher. Multivariate analysis revealed that longer operative duration (for 30 minutes increase;odds ratio 1.27, 95% CI 1.01-1.51, p=0.039) and positivity for preoperative bacterial culture (odds ratio 5.03, 95% CI 1.31-19.2, p=0.018) were independent risk factors for severe postoperative pneumonia, but not for all incidences of postoperative pneumonia. Of note, in only 5 of the 22 patients with pneumonia, the same pathogenic species were detected preoperatively and after the onset of pneumonia. Conclusions: Our results imply that preoperative bacterial culture may be useful to predict severe postoperative pneumonia. However, it may not be useful in determining pathogenic bacteria responsible for postoperative pneumonia

Clinical outcomes of laparoscopic and endoscopic cooperative surgery for gastric gastrointestinal stromal tumor

Background: Laparoscopic and endoscopic cooperative surgery (LECS) is a well-recognized surgical procedure for gastric gastrointestinal stromal tumor (GIST). In this report, we describe the clinical outcomes of LECS procedures for gastric GIST in our institution. Methods: We performed LECS procedures, including classical LECS, inverted LECS, closed LECS, and combination of laparoscopic and endoscopic approaches to neoplasia with non-exposure technique (CLEAN-NET), in 40 gastric intraluminal and intramural type GIST patients, whose tumors were ≤ 50 mm in diameter, between September 2012 and December 2020. The patient background, surgical outcomes, postoperative morbidity and mortality, as well as the tumors' clinicopathological characteristics were analyzed retrospectively. Results: Pathological findings showed that most patients had a low or very low risk of tumor recurrence, while one patient had a high risk according to the modified-Fletcher's classification. The median length of postoperative hospital stay was 7 days. Only one patient had severe postoperative grade III complications according to the Clavien-Dindo (C-D) classification, after closed LECS, but was treated successfully with endoscopic hemostasis for postoperative hemorrhage. The remaining patients treated with LECS did not have severe complications. During the follow-up period (median, 31 months), all patients were disease-free, with no tumor recurrence or metastases. Conclusion: LECS is a safe surgical procedure for gastric intraluminal and intramural type GIST ≤ 50 mm in diameter, with good clinical outcomes

Anti‐PD‐1 monoclonal antibody‐resistant esophageal squamous cell carcinoma showing the abscopal effect: A case report with T‐cell receptor/B‐cell receptor repertoire analysis

Abstract Background Several clinical trials of nivolumab have reported good results, including those in patients with advanced esophageal squamous cell carcinoma. However, the response rate of this drug remains poor. Notably, a rare phenomenon called abscopal effect refers to the regression of irradiated and nonirradiated distant tumors after local radiotherapy. Although the mechanism of this effect remains unclear, the antitumor immunity induced by radiotherapy is considered to be the most important factor. Case A 66‐year‐old man with recurrent nivolumab‐resistant esophageal squamous cell carcinoma along with left‐side cervical and abdominal para‐aortic lymph node metastases was treated with a 40 Gy (10 fractions) dose of radiotherapy to the left‐side cervical lymph node metastasis as a palliative treatment, which caused neck pain. In addition, nivolumab administration was resumed the day after completion of radiotherapy. Three months after radiotherapy, the irradiated lesion on the left neck had regressed to a scar‐like lesion. Furthermore, the previously progressive abdominal para‐aortic lymph nodes outside the irradiation area shrank (abscopal effect). T‐cell receptor and B‐cell receptor (TCR/BCR) repertoire analyses before and after radiotherapy revealed that radiotherapy led to changes in the TCR/BCR repertoire. Conclusion Changes in the TCR/BCR repertoire may be a part of the mechanism underlying the abscopal effect. The findings of the present case suggest that the combination of immune checkpoint inhibitors and radiotherapy is a promising treatment approach even for patients with immune checkpoint inhibitor‐resistant cancer

Systemic inflammation score as a preoperative prognostic factor for patients with pT2–T4 resectable gastric cancer: a retrospective study

Abstract Background Systemic inflammation has been reported to be associated with cancer progression and metastasis. Systemic inflammation score (SIS), calculated from preoperative serum albumin level and lymphocyte-to-monocyte ratio, has been shown to be a novel prognostic factor for several types of tumors. This study aimed to evaluate the prognostic value of the SIS in patients with pT2–4 resectable gastric cancer (GC). Methods Total 97 patients with pT2–4 GC who underwent curative surgery from 322 cases between 2009 and 2015 in Fukushima Medical University Hospital were included. We performed univariate and multivariate analyses to evaluate the usefulness of preoperative SIS and other prognostic factors for relapse-free survival (RFS) and overall survival (OS). Results The higher SIS score was associated with undifferentiated cancer and recurrence. Univariate analysis of RFS identified deeper tumor invasion and higher SIS were significant risk factors and multivariate analysis revealed that both of them were independent prognostic factors for RFS. As for OS, age, tumor invasion, SIS and LNR were significantly correlated with RFS. In multivariate analysis, tumor invasion, SIS and LNR were independent prognostic factors for OS. Conclusions SIS was an independent prognostic factor for RFS and OS in pT2–4 resectable gastric cancer patients who underwent curative gastrectomy

Phase I/II clinical trial of nivolumab in combination with oligo-fractionated irradiation for unresectable advanced or recurrent gastric cancer

Abstract Background Although immune checkpoint inhibitors (ICI) targeting for PD-1 axis is a promising approach for advanced gastric cancer (GC) patients, the response rate is still limited. Induction of synergistic effect of irradiation with ICI targeting for the PD-1 axis can be an attractive strategy. The aim of this study was to assess the effect of the combination of irradiation with anti-PD-1 therapy for advanced GC. Methods We conducted a single-arm, phase I/II trial in GC patients treated with a combination of nivolumab and oligo-fractionated irradiation (22.5 Gy/5 fractions/5 days) (NCT03453164). Eligible patients (n = 40) had unresectable advanced or recurrent GC which progressed after primary and secondary chemotherapy with more than one lesion. The primary endpoint is the disease control rate (DCR) of non-irradiated target lesions and the secondary endpoints are the median survival time (MST), safety, and DCR of irradiated lesions. Results We observe that the DCR for the non-irradiated target as the abscopal effect is 22.5% (90% confidence interval (CI), 12.3–36.0), and the DCR for the irradiated lesion is 40.0% (90% CI, 26.9–54.2). The median survival time is 230 days (95% CI, 157–330), and grade 3 and higher adverse events (AEs) are observed in 16 patients (39 %) with no obvious additional AEs when adding irradiation. Conclusions The present study suggests that the combination of nivolumab with oligo-fractionated irradiation has the potential to induce a promising anti-tumor effect for advanced GC

Combination of oligo-fractionated irradiation with nivolumab can induce immune modulation in gastric cancer.

BACKGROUND: Tumor-associated antigen (TAA)-specific CD8(+) T cells are essential for nivolumab therapy, and irradiation has been reported to have the potential to generate and activate TAA-specific CD8(+) T cells. However, mechanistic insights of T-cell response during combinatorial immunotherapy using radiotherapy and nivolumab are still largely unknown. METHODS: Twenty patients included in this study were registered in the CIRCUIT trial (ClinicalTrials.gov, NCT03453164). All patients had multiple distant metastases and were intolerance or had progressed after primary and secondary chemotherapy without any immune checkpoint inhibitor. In the CIRCUIT trial, eligible patients were treated with a total of 22.5 Gy/5 fractions/5 days of radiotherapy to the largest or symptomatic lesion prior to receiving nivolumab every 2 weeks. In these 20 patients, T-cell responses during the combinatorial immunotherapy were monitored longitudinally by high-dimensional flow cytometry-based, multiplexed major histocompatibility complex multimer analysis using a total of 46 TAAs and 10 virus epitopes, repertoire analysis of T-cell receptor β-chain (TCRβ), together with circulating tumor DNA analysis to evaluate tumor mutational burden (TMB). RESULTS: Although most TAA-specific CD8(+) T cells could be tracked longitudinally, several TAA-specific CD8(+) T cells were detected de novo after irradiation, but viral-specific CD8(+) T cells did not show obvious changes during treatment, indicating potential irradiation-driven antigen spreading. Irradiation was associated with phenotypical changes of TAA-specific CD8(+) T cells towards higher expression of killer cell lectin-like receptor subfamily G, member 1, human leukocyte antigen D-related antigen, T-cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domain, CD160, and CD45RO together with lower expression of CD27 and CD127. Of importance, TAA-specific CD8(+) T cells in non-progressors frequently showed a phenotype of CD45RO(+)CD27(+)CD127(+) central memory T cells compared with those in progressors. TCRβ clonality (inverted Pielous evenness) increased and TCRβ diversity (Pielous evenness and Diversity Evenness score) decreased during treatment in progressors (p=0.029, p=0.029, p=0.012, respectively). TMB score was significantly lower in non-progressors after irradiation (p=0.023). CONCLUSION: Oligo-fractionated irradiation induces an immune-modulating effect with potential antigen spreading and the combination of radiotherapy and nivolumab may be effective in a subset of patients with gastric cancer