Safety and Efficacy of Conversion Therapy After Systemic Chemotherapy in Advanced Esophageal Cancer with Distant Metastases: A Multicenter Retrospective Observational Study.

BACKGROUND: Patients with esophageal squamous cell carcinoma (ESCC) with distant metastasis were treated with systemic chemotherapy. Recent advances in multimodal treatments have made conversion therapy a viable option for patients with incurable ESCC. OBJECTIVE: We aimed to assess the safety and efficacy of conversion therapy for ESCC with distant metastases. METHODS: Conversion therapy was defined as surgery or chemoradiotherapy (CRT) used to cure tumors that were previously considered incurable because of distant metastasis. We conducted a retrospective review of patients who underwent ESCC conversion therapy and assessed the treatment outcomes, including adverse events and survival rates. RESULTS: A total of 147 patients from 22 institutions were included. Systemic chemotherapy was initially administered to all patients. The most common M1 factor was the para-aortic lymph node, accounting for 55% of cases. Following the initial treatment, 116 patients underwent surgery, with 31 receiving CRT as conversion therapy. Postoperative complications in surgery patients included pneumonia (16%), anastomotic leakage (7%), and recurrent laryngeal nerve palsy (6%). During CRT, 18% of patients developed grade 3 or higher non-hematological toxicities. The 5-year overall survival (OS) rate was 31.7%. Pathological responders had significantly longer OS than non-responders (hazard ratio 0.493, p = 0.012). The distribution of distant metastasis, regimen type, clinical response, and conversion therapy modality did not have a significant impact on OS. CONCLUSIONS: Conversion therapy can be safely performed for ESCC with distant metastasis and has a favorable prognosis.

The real-world data of immune-checkpoint inhibitor combination therapy for unresectable or metastatic esophageal cancer: a multi-institutional cohort study.

BACKGROUND: The real-world efficacy, feasibility, and prognostic factors of immune-checkpoint inhibitor combination therapy for unresectable or metastatic esophageal cancer are not fully established. METHODS: This multi-institutional retrospective cohort study evaluated 71 consecutive patients treated with immune-checkpoint inhibitor combination therapy for esophageal cancer between March 2021 and December 2022. We assessed tumor response, safety, and long-term survival. RESULTS: In patients with measurable lesions, the response rate was 58%, and the disease control rate for all enrolled patients was 80%. Five patients (7.0%) underwent successful conversion surgery. Grade 3 or higher immune-related adverse events occurred in 13% of patients, and one patient (1.4%) died due to cholangitis. Median progression-free survival was 9.7 (95% confidence interval: 6.5-not reached). C-reactive protein levels and performance status were identified as significant predictors of progression-free survival through Cox proportional hazards analysis. CONCLUSIONS: Immune-checkpoint inhibitor combination therapy for esophageal cancer demonstrated comparable tumor response, safety, and long-term survival to previous randomized clinical trials. Patients with good performance status and low C-reactive protein levels may be suitable candidates for this treatment.

The tumor cell-intrinsic cGAS-STING pathway is associated with the high density of CD8+ T cells after chemotherapy in esophageal squamous cell carcinoma.

BACKGROUND: Chemotherapy has the potential to induce CD8+ T-cell infiltration in the tumor microenvironment (TME) and activate the anti-tumor immune response in several cancers including esophageal squamous cell carcinoma (ESCC). The tumor cell-intrinsic cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway has been known as a critical component for regulating immune cell activation in the TME. However, its effect on the infiltration of immune cells induced by chemotherapy in the ESCC TME has not been investigated. METHODS: We examined the effect of the tumor-cell intrinsic cGAS-STING pathway on the infiltration of CD8+ T cells induced by chemotherapy in ESCC using ESCC cell lines and surgically resected ESCC specimens from patients who received neoadjuvant chemotherapy (NAC). RESULTS: We found that chemotherapeutic agents, including 5-fluorouracil (5-FU) and cisplatin (CDDP), activated the cGAS-STING pathway, consequently inducing the expression of type I interferon and T-cell-attracting chemokines in ESCC cells. Moreover, the tumor cell-intrinsic expression of cGAS-STING was significantly and positively associated with the density of CD8+ T cells in ESCC after NAC. However, the tumor cell-intrinsic expression of cGAS-STING did not significantly impact clinical outcomes in patients with ESCC after NAC. CONCLUSION: Our findings suggest that the tumor cell-intrinsic cGAS-STING pathway might contribute to chemotherapy-induced immune cell activation in the ESCC TME.

M2 tumor-associated macrophages resist to oxidative stress through heme oxygenase-1 in the colorectal cancer tumor microenvironment.

M2 tumor-associated macrophages (M2-TAMs) promote cancer cell proliferation and metastasis in the TME. Our study aimed to elucidate the mechanism of increased frequency of M2-TAMs infiltration in the colorectal cancer (CRC)-TME, focusing on the resistance to oxidative stress through nuclear factor erythroid 2-related factor 2 (Nrf2) pathway. In this study, we evaluated the correlation between M2-TAM signature and mRNA expression of antioxidant related genes using public datasets, and the expression level of antioxidants in M2-TAMs by flow cytometry and the prevalence of M2-TAMs expressing antioxidants by immunofluorescence staining using surgically resected specimens of CRC (n = 34). Moreover, we generated M0 and M2 macrophages from peripheral blood monocytes and evaluated their resistance to oxidative stress using the in vitro viability assay. Analysis of GSE33113, GSE39582, and The Cancer Genome Atlas (TCGA) datasets indicated that mRNA expression of HMOX1 (heme oxygenase-1 (HO-1)) was significantly positively correlated with M2-TAM signature (r = 0.5283, r = 0.5826, r = 0.5833, respectively). The expression level of both Nrf2 and HO-1 significantly increased in M2-TAMs compared to M1- and M1/M2-TAMs in the tumor margin, and the number of Nrf2+ or HO-1+M2-TAMs in the tumor stroma significantly increased more than those in the normal mucosa stroma. Finally, generated M2 macrophages expressing HO-1 significantly resisted to oxidative stress induced by H2O2 in comparison with generated M0 macrophages. Taken together, our results suggested that an increased frequency of M2-TAMs infiltration in the CRC-TME is related to Nrf2-HO-1 axis mediated resistance to oxidative stress.

ARID1A deficiency is targetable by AKT inhibitors in HER2-negative gastric cancer.

BACKGROUND: The PI3K/AKT signaling pathway is frequently activated in gastric cancer (GC); however, AKT inhibitors are not effective in unselected GC patients in clinical trials. Mutations in AT-rich interactive domain 1A (ARID1A), which are found in approximately 30% of GC patients, activate PI3K/AKT signaling, suggesting that targeting the ARID1A deficiency-activated PI3K/AKT pathway is a therapeutic candidate for ARID1A-deficient GC. METHODS: The effect of AKT inhibitors was evaluated using cell viability and colony formation assays in ARID1A-deficient and ARID1A knockdown ARID1A-WT GC cells as well as in HER2-positive and HER2-negative GC. The Cancer Genome Atlas cBioPortal and Gene Expression Omnibus microarray databases were accessed to determine the extent of dependence of GC cell growth on the PI3K/AKT signaling pathway. RESULTS: AKT inhibitors decreased the viability of ARID1A-deficient cells and the inhibitory effect was greater in ARID1A-deficient/HER2-negative GC cells. Bioinformatics data suggested that PI3K/AKT signaling plays a greater role in proliferation and survival in ARID1A-deficient/HER2-negative GC cells than in ARID1A-deficient/HER2-positive cells, supporting the higher therapeutic efficacy of AKT inhibitors. CONCLUSIONS: The effect of AKT inhibitors on cell proliferation and survival is affected by HER2 status, providing a rationale for exploring targeted therapy using AKT inhibitors in ARID1A-deficient/HER2-negative GC.

Down-regulation of stimulator of interferon genes (STING) expression and CD8+ T-cell infiltration depending on HER2 heterogeneity in HER2-positive gastric cancer.

BACKGROUND: HER2 signaling might be involved in the regulation of immune cell activation in the tumor microenvironment (TME) of gastric cancer (GC). However, the relationship between HER2 status and immune cell condition in the HER2-positive GC TME is not clearly understood. METHODS: To investigate the effect of HER2 signaling on the activation of the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway, which contributes to immune cell activation in the GC TME, we evaluated the associations among the expressions of HER2, cGAS-STING, and the number of CD8+ tumor-infiltrating lymphocytes (TIL) by considering HER2 heterogeneity in HER2-positive GC tissues. We also examined the effect of HER2 signaling on the activation of STING signaling in vitro using human HER2-positive GC cell lines. RESULTS: The expression of HER2 is highly heterogeneous in HER2-positive GC tissues, and we found that the number of CD8+ TIL in HER2 high areas was significantly lower than that in HER2 low areas in HER2-positive GC tissues. Intriguingly, the tumor cell-intrinsic expression of STING, but not cGAS, was also significantly lower in the HER2 high areas than the HER2 low areas in HER2-positive GC tissues. Moreover, in vitro experiments, we demonstrated that the blockade of HER2 signaling increased the expression of STING and its target genes, including IFNB1, CXCL9/10/11, and CCL5, in HER2-positive GC cell lines. CONCLUSIONS: Our results suggest that HER2 signaling might suppress immune cell activation in the GC TME by inhibiting STING signaling in tumor cells in HER2-positive GC.

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

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.

[Remodeling of the Tumor Microenvironment by Radiotherapy through the cGAS-STING Pathway in Esophageal Squamous Cell Carcinoma].

It has been reported that tumor cell-intrinsic cyclic GMP-AMP synthase(cGAS)-stimulator of interferon genes(STING) pathway is essential for radiotherapy(RT)-induced activation of anti-tumor immune responses. However, its role in the RT- induced remodeling of the tumor microenvironment(TME)in esophageal squamous cell carcinoma(ESCC), is largely unknown. In this study, we found that the tumor cell-intrinsic cGAS-STING pathway is a critical component for RT-induced activation of immune cells in the TME through the induction of type Ⅰ interferon and C-X-C motif chemokine ligand 10 in tumor cells in ESCC. However, at the same time, the tumor cell-intrinsic cGAS-STING pathway is also involved in RT-triggered infiltration and polarization of immunosuppressive CD163+ tumor-associated macrophages (TAM) through the induction of interleukin 34 (IL-34) in tumor cells in ESCC. Our findings suggest that targeting IL-34 to impede the infiltration and polarization of CD163+ TAM could potentially enhance the efficacy of RT-induced immune cell activation in ESCC TME.

[A Case of MSI-High Sigmoid Colon Cancer in Which Long-Term Survival Was Achieved by Pembrolizumab for Recurrent Lesions Resistant to Conventional Chemotherapy].

The patient underwent sigmoidectomy with D3 lymph node dissection and partial bladder resection for sigmoid colon cancer(cT4bN1M0, cStage Ⅲa), after preoperative chemotherapy with mFOLFOX plus panitumumab, and FOLFOXIRI plus bevacizumab. Postoperative adjuvant chemotherapy was performed by 8 courses of CAPOX. He relapsed hilar lymph nodes and peritoneal dissemination after 13 months after surgery, he underwent resection of the recurrent lesions. Four months after, he developed recurrence in liver and peritoneum. Although he was treated with FOLFIRI plus ramucirumab or aflibercept, resulted in progression of disease, then he received trifluridine tipiracil hydrochloride plus bevacizumab. At this point, the Japanese health insulance had started to cover pembrolizumab, this therapy was started as the fourth chemotherapy after the diagnosis of high frequency microsatellite instability(MSI), and then tumor markers rapidly declined. He underwent 38 courses of pembrolizumab, the recurrent lesions both liver and peritoneum disappeared. He had stoma closure, peritoneal dissemination disappeared not only intraoperatively but also in histologically from the peritoneal scar. He has received pembrolizumab for 4 years without another recurrence. Here, we report a case of MSI-high sigmoid colon cancer in which long-term survival was achieved by pembrolizumab for recurrent lesions resistant to conventional chemotherapy.

[A Case of Perforation of the Duodenum during Chemotherapy with Ramucirumab plus Nab-Paclitaxel for Advanced Gastric Cancer].

A 70-year-old male patient was diagnosed with advanced gastric cancer with para-aortic lymph node metastasis. After diagnostic laparoscopy, the patient received 2 courses of neoadjuvant chemotherapy. Subsequently, distal gastrectomy, D2 plus para-aortic lymph node dissection, and Roux-en-Y reconstruction were performed. An enlarged lymph node(No. 16b2)was identified during surgery. The histopathological diagnosis revealed ypT4b, ypN3b, cM1(LYM; No. 16), Stage ⅣB. Chemotherapy with ramucirumab plus nab-paclitaxel was administered at 6 weeks postoperatively. However, after 2 courses of chemotherapy, the patient developed an abscess discharge from the wound, which was confirmed by an abdominal CT scan and diagnosed as an intra-abdominal abscess derived from duodenal perforation. The abscess was drained percutaneously. Subsequently, chemotherapy with nab-paclitaxel, nivolumab, and trifluridine/tipiracil hydrochloride was administered. After the appearance of brain metastases, the treatment was shifted to palliative care. The patient died 2 years and 7 months later from the primary disease.

Immune escape mechanism behind resistance to anti-PD-1 therapy in gastrointestinal tract metastasis in malignant melanoma patients with multiple metastases.

Immunotherapy targeting the PD-1 axis has recently become a standard treatment for patients with malignant melanoma. However, approximately 25% of reported malignant melanoma patients who initially responded to immunotherapy with anti-PD-1 mAb had progressive disease, and the immune escape mechanism behind resistance to anti-PD-1 therapy is not yet fully understood in the clinical setting. In the present study, we included four malignant melanoma patients, in whom multiple metastases other than gastrointestinal tract metastasis had disappeared or were controlled under multidisciplinary treatment that included anti-PD-1 therapy. Using IHC, we evaluated the immune status of surgically resected specimens of gastrointestinal tract metastases as acquired resistant lesion to anti-PD-1 therapy. We herein report that the down-regulated expression of HLA class I and up-regulated expression of inhibitory immune checkpoint ligands, CD155 (ligand for T cell immunoglobulin and ITIM domain, TIGIT) and carcinoembryonic antigen-related adhesion molecule-1 (ligand for TIM-3), were observed on the tumor cells in the metastatic gastrointestinal tract tumors. Moreover, our results also suggest that stromal TGF-ß may be related to this down-regulation of HLA class I expression on the tumor cells. In conclusion, it is likely that the down-regulated expression of HLA class I and additional expression of inhibitory immune checkpoint ligands other than PD-L1 on the tumor cells were acquired in the gastrointestinal tract metastasis during anti-PD-1 therapy in the malignant melanoma patients.

Role of the cGAS-STING pathway in regulating the tumor-immune microenvironment in dMMR/MSI colorectal cancer.

Deficient mismatch repair (dMMR)/microsatellite instability (MSI) colorectal cancer (CRC) has high immunogenicity and better prognosis compared with proficient MMR (pMMR)/microsatellite stable (MSS) CRC. Although the activation of the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway has been considered to contribute to the high number of CD8+ TILs, its role in dMMR/MSI CRC is largely unknown. In this study, to examine the role of the cGAS-STING pathway on the recruitment of CD8+ TILs in dMMR/MSI CRC, we used public datasets and clinical tissue samples in our cohorts to evaluate the expression of cGAS, STING, and CD8+ TILs in pMMR/MSS and dMMR/MSI CRCs. According to the analysis of public datasets, the expression of cGAS-STING, CD8 effector gene signature, and CXCL10-CCL5, chemoattractants for CD8+ TILs which regulated by the cGAS-STING pathway, was significantly upregulated in dMMR/MSI CRC, and the expression of cGAS-STING was significantly associated with the expression of CD8 effector gene signature. Immunohistochemistry staining of the clinical tissue samples (n = 283) revealed that cGAS-STING was highly expressed in tumor cells of dMMR CRC, and higher expression of cGAS-STING in tumor cells was significantly associated with the increased number of CD8+ TILs. Moreover, we demonstrated that the downregulation of MMR gene in human CRC cell lines enhanced the activation of the cGAS-STING pathway. Taken together, for the first time, we found that dMMR/MSI CRC has maintained a high level of cGAS-STING expression in tumor cells, which might contribute to abundant CD8+ TILs and immune-active TME.

Incidence of upper extremity deep vein thrombosis in the retrosternal reconstruction after esophagectomy.

BACKGROUND: Upper extremity deep vein thrombosis (UEDVT) is relatively rare but cannot be negligible because it can cause fatal complications. Although it is reported that the occurrence rate of UEDVT has increased due to central venous catheter (CVC), cancer, and surgical invasion, there is still limited information for esophagectomy. The aim of this study was to evaluate the clinical factors, including CVC placement and thromboprophylaxis approach, as well as retrosternal space's width as a predictive factor for UEDVT in patients receiving esophagectomy. METHODS: This study included 66 patients who underwent esophagectomy with retrosternal reconstruction using a gastric tube. All patients routinely underwent contrast-enhanced computed tomography (CT) on the 4th postoperative day. Low-molecular-weight-heparin (LMWH) was routinely administered by the 2nd postoperative day. To evaluate retrosternal space's width, (a) The distance from sternum to brachiocephalic artery and (b) the distance from sternum to vertebra were measured by preoperative CT, and the ratio of (a) to (b) was defined as the width of retrosternal space. RESULTS: Among all patients, 11 (16.7%) suffered from UEDVT, and none was preoperatively received CVC placement, while 7 were inserted in non-UEDVT cases. Retrosternal space's width in patients with UEDVT was significantly smaller than that in patients without UEDVT (0.17 vs. 0.26; P < 0.0001). A cutoff value of the width was 0.21, which has high sensitivity (87%) and specificity (82%) for UEDVT prediction, respectively. CONCLUSION: The existence of CVC may not affect the development of UEDVT, but preoperative evaluation of retrosternal ratio may predict the occurrence of UEDVT.

ARID1A deficiency in EBV-positive gastric cancer is partially regulated by EBV-encoded miRNAs, but not by DNA promotor hypermethylation.

AT-rich interactive domain 1A (ARID1A), which is a tumor suppressor gene, is frequently mutated in Epstein-Barr virus-positive gastric cancer [EBV (+) GC]. While most ARID1A mutations in GC are truncating mutations, leading to loss of ARID1A protein expression, epigenetic modifications appear to contribute to ARID1A deficiency in EBV (+) GC harboring wild-type ARID1A. Based on the significant role of epigenetic modifications in EBV (+) GC that contributes to ARID1A deficiency, the methylation status of ARID1A was evaluated in EBV-infected cells and GC patients using a publicly available microarray and the Cancer Genome Atlas (TCGA) database. EBV-encoded miRNAs that potentially target ARID1A were identified as an additional epigenetic modulator by computational prediction. In vitro experiments were conducted to evaluate how EBV-encoded miRNAs affected ARID1A mRNA and protein levels. In clinical GC samples, the expression of predicted miRNAs and ARID1A and the mutation status of ARID1A was evaluated. As results, ARID1A was not hypermethylated in EBV (+) GC samples or EBV-infected GC cells. EBV infection did not alter ARID1A mRNA levels, suggesting that ARID1A protein deficiency was caused by post-transcriptional gene silencing in ARID1A-WT EBV (+) GC. Overexpression of miR-BART11-3p and miR-BART12, which were identified as miRNAs that potentially bind ARID1A, suppressed ARID1A protein expression in MKN7 and NCI-N87 cells. Highly expressed miR-BART11-3p and miR-BART12 were correlated with decreased ARID1A levels in GC tumors which did not harbor ARID1A mutations. The present findings revealed that ARID1A expression was epigenetically regulated by miR-BART11-3p and miR-BART12 in EBV (+) GC.

Therapeutic potential of anti-VEGF receptor 2 therapy targeting for M2-tumor-associated macrophages in colorectal cancer.

BACKGROUND: Although immunotherapy with immune checkpoint inhibitors (ICIs) has become a standard therapeutic strategy in colorectal cancer (CRC) exhibiting microsatellite instability-high, limited patients benefit from this new approach. To increase the efficacy of ICIs in CRC patients, it is crucial to control the function of immunosuppressive cells in the tumor microenvironment. M2-tumor-associated macrophages (TAMs) are key immunosuppressive cells and promote tumor growth, angiogenesis, and epithelial-mesenchymal transition. In the present study, we focused on the VEGF signaling pathway in M2-TAMs to control their inhibitory function. METHODS: We evaluated the population of M2-TAMs, the VEGF receptor 2 (VEGFR2) expression on M2-TAMs, and the correlation between HIF-1α-positive cells and VEGFR2 expression levels on M2-TAMs in CRC using the analysis of The Cancer Genome Atlas colorectal adenocarcinoma dataset (n = 592), the flow cytometry of freshly resected surgical specimens of CRC (n = 20), and the immunofluorescence staining of formalin-fixed paraffin-embedded whole tissue samples of CRC (n = 20). Furthermore, we performed a functional assay of M2 macrophages through the VEGF/VEGFR2 signaling pathway in vitro. RESULTS: The population of M2-TAMs and their VEGFR2 expression significantly increased in the tumor compared to the normal mucosa in the CRC patients. HIF1-α-positive cells significantly correlated with the VEGFR2 expression level of M2-TAMs. M2 macrophages induced by cytokines in vitro produced TGF-ß1 through the VEGF/VEGFR2 signaling pathway. CONCLUSIONS: Our results suggest that anti-VEGFR2 therapy may have therapeutic potential to control the immune inhibitory functions of M2-TAMs in CRC, resulting in enhanced efficacy of immunotherapy with ICIs.

Selective sensitivity of EZH2 inhibitors based on synthetic lethality in ARID1A-deficient gastric cancer.

BACKGROUND: AT-rich interactive domain 1A (ARID1A) is a tumor suppressor gene that is frequently mutated in gastric cancer (GC). Although ARID1A mutations are not a druggable target for conventional treatments, novel therapeutic strategies based on a synthetic lethal approach are effective for ARID1A-deficient cancers. The histone methyltransferase EZH2 acts in a synthetic lethal manner in ARID1A-mutated ovarian cancer, although its role in GC remains unknown. METHODS: The selective sensitivity of the EZH2 inhibitors for ARID1A-deficient GC cells was evaluated using cell viability and colony formation assays. The expression of PI3K/AKT signaling genes were investigated using TCGA's cBioPortal database to determine whether the homeostasis between ARID1A and EZH2 is related to cell proliferation and survival via the PI3K/AKT signaling pathway. We also evaluated the phosphorylation of PI3K/AKT signaling proteins in ARID1A knock downed ARID1A-WT GC cells. RESULTS: EZH2 inhibitors decreased the viability of ARID1A-deficient cells in a dose-dependent manner and demonstrated the selective sensitivity to ARID1A-deficient cells in vitro experiment system. Bioinformatics approach revealed that the PI3K/AKT signaling was tended to be activated in ARID1A-deficient GC enhancing cell viability and, furthermore, down-regulation of EZH2 in ARID1A-deficient GC was related to normalization of PI3K/AKT signaling pathway. The cell experiment revealed that phosphorylated AKT was upregulated in ARID1A-deficent GC cells. CONCLUSIONS: The present findings provide a rationale for the selective sensitivity of EZH2 inhibitors against ARID1A-deficient GC and suggest the potential efficacy of targeted therapy using EZH2 inhibitors in this patient population.

Functional benefits of the double flap technique after proximal gastrectomy for gastric cancer.

BACKGROUND: Proximal gastrectomy is a widely performed procedure that has become more common with an increasing number of proximal gastric cancer cases. Several types of reconstructive procedures after proximal gastrectomy have been developed, and it remains controversial which procedure is the most advantageous with regard to the preservation of postoperative gastric stump function and nutritional status. In the present study, we retrospectively analyzed reconstructive procedures in a consecutive case series for proximal gastrectomy, primarily focusing on postoperative body weight maintenance, nutritional status, and gastric remnant functional preservation. METHODS: We enrolled 69 patients who had undergone proximal gastrectomy for gastric cancer in our institute between 2005 and 2020. Short-term complications, preservation of gastric remnant functions, nutritional status, and post-operative weight changes were compared. RESULTS: After proximal gastrectomy, the numbers of patients who underwent direct esophago-gastrostomy, jejunal interposition, double tract reconstruction, and the double flap technique were 9, 10, 14, and 36, respectively. The patients in whom the double flap technique was performed suffered no reflux esophagitis after surgery. Prevalence of gastric residual at 12 months after surgery was lowest in the double flap technique group. Moreover, the double flap technique group had a better tendency regarding post-operative changes of serum albumin ratios. Furthermore, the post-operative body weight change ratio of the double flap technique group was smallest among all groups and was significantly better than that of the double tract group. CONCLUSIONS: The double flap technique after proximal gastrectomy was considered the most effective technique for reconstruction which leads to better bodyweight maintenance, and results in less reflux esophagitis.

[Immunotherapy Targeting Tumor-Associated Carbohydrate Antigens in Deficient Mismatch Repair Colorectal Cancer].

The Tn antigen is the most prevalent tumor-associated carbohydrate antigen. It interacts with macrophage galactose-specific lectin(MGL)on dendric cells and macrophages, driving immune inhibitory signals. Colorectal cancer(CRC)exhibiting deficient mismatch repair(dMMR)is characterized by tumor-infiltrating lymphocytes(TILs), the expression of immune checkpoint molecules, and immune evasion. We recently reported that Tn antigen expression was associated with dMMR and that dMMR CRCs with strong Tn antigen expression demonstrated CD8+ T cell exclusion and a lack of PD-L1 expression. Our findings suggest that the immune cold subset of dMMR CRCs with strong Tn antigen may be effectively treated with immune checkpoint blockade therapy or cellular immunotherapy targeting Tn antigens.

[Significance and Treatment Strategy of Glasgow Prognostic Score in High Risk Stage â ¡ Colorectal Cancer].

In this study, we investigated the usefulness of Glasgow prognostic score(GPS)as a prognostic factor for Stage Ⅱ colorectal cancer, and the treatment strategy by individualizing adjuvant chemotherapy. We enrolled 86 patients with Stage Ⅱ primary colorectal cancer who underwent curative resection. This study examines the prognostic significance of clinicopathological factors and GPS, NLR, LMR, PLR. Multivariate analyses was performed to evaluate the factors affecting recurrence free survival. The 5-year OS was 92.5%, and the RFS was 86% in Stage Ⅱ colorectal cancer. The recurrence rate was 12.8%. In multivariate analysis, GPS(HR: 13.66, p=0.005)was extracted as an independent poor prognosis factor. In comparison of survival rates, RFS of GPS 0, 1 was 95.2% and that of GPS 2 43.8%, and GPS 2 had a significantly poor prognosis(p< 0.01). GPS 2 is an independent high risk factor for recurrence of Stage Ⅱ colorectal cancer. In order to improve the prognosis of Stage Ⅱ colorectal cancer, individualized adjuvant chemotherapy is important.

[A Case of Laparoscopic Surgery for Preoperatively Diagnosed Gastric Metastasis of Lung Cancer].

The patient was a 66-year-old male who had undergone an operation for lung cancer and solitary brain metastases. Follow- up PET-CT after 1 year detected FDG accumulation in the stomach. We performed esophagogastroscopy and found an approximately 20 mm-sized Type 2 tumor on the greater curvature of the upper stomach. A pathological diagnosis of lung adenocarcinoma metastasis in the stomach was made. Laparoscopic surgery was performed on the metastatic lesion to prevent bleeding and perforation, and resection was achieved with minimal invasion. The current development of chemotherapy, including immunotherapy, has contributed to the improved prognosis of cancer patients, including those with lung metastasis in the stomach. Considering these backgrounds, preventive surgical resection under laparoscopy may be an effective approach for improving prognosis and preventing acute life-threatening adverse events. We report this case along with a literature review.