Optimal extent of lymph node dissection for high-risk gastric cancer stratified by a national clinical database risk calculator.

BACKGROUND: For patients with gastric cancer, a well-balanced treatment that considers both oncological aspects and surgical risk is demanded. This study aimed to explore the optimal extent of lymph node dissection (LND) for patients with gastric cancer according to surgical risk, stratified by the risk calculator system produced by the Japan National Clinical Database (NCD). PATIENTS AND METHODS: We retrospectively evaluated 187 patients who underwent radical gastrectomy for gastric cancer. Using the median predicted anastomotic leak rate obtained by the NCD risk calculator as the cutoff value, we classified 97 and 90 patients as having high and low risks, respectively. RESULTS: In low-risk patients, although limited LND reduced the postoperative intraabdominal infectious complications (IAIC), multivariate analysis revealed standard LND as an independent prognostic factor that improved Relapse-free survival (RFS). In high-risk patients, the rates of postoperative IAIC and RFS were similar between standard and limited LND. Pancreatic fistula was not observed in the limited dissection group. CONCLUSION: Limited LND might be the optimal treatment strategy for patients with gastric cancer with high surgical risk.

Involvement of CX3CR1+ cells appearing in the abdominal cavity in the immunosuppressive environment immediately after gastric cancer surgery.

BACKGROUND: Gastric cancer is primarily treated by surgery; however, little is known about the changes in the intraperitoneal immune environment and the prognostic impact of surgery. Surgical stress and cancer-associated inflammation cause immune cells to mobilize into the abdominal cavity via numerous cytokines. One such cytokine, CX3CR1, has various immune-related functions that remain to be fully explained. We characterized the intraperitoneal immune environment by investigating CX3CR1+ cells in intraperitoneal lavage fluid during gastric cancer surgery. METHODS: Lavage fluid samples were obtained from a total of 41 patients who underwent gastrectomy. The relative expression of various genes was analyzed using quantitative real-time PCR. The association of each gene expression with clinicopathological features and surgical outcomes was examined. The fraction of CX3CR1+ cells was analyzed by flow cytometry. Cytokine profiles in lavage fluid samples were investigated using a cytometric beads array. RESULTS: CX3CR1high patients exhibited higher levels of perioperative inflammation in blood tests and more recurrences than CX3CR1low patients. CX3CR1high patients tended to exhibit higher pathological T and N stage than CX3CR1low patients. CX3CR1 was primarily expressed on myeloid-derived suppressor cells and tumor-associated macrophages. In particular, polymorphonuclear myeloid-derived suppressor cells were associated with perioperative inflammation, pathological N, and recurrences. These immunosuppressive cells were associated with a trend toward unfavorable prognosis. Moreover, CX3CR1 expression was correlated with programmed death-1 expression. CONCLUSIONS: Our results suggest that CX3CR1+ cells are associated with an acute inflammatory response, tumor-promotion, and recurrence. CX3CR1 expression could be taken advantage of as a beneficial therapeutic target for improving immunosuppressive state in the future. In addition, analysis of intra-abdominal CX3CR1+ cells could be useful for characterizing the immune environment after gastric cancer surgery.

Effects of an artificial pancreas on postoperative inflammation in patients with esophageal cancer.

PURPOSES: Subtotal esophagectomy for esophageal cancer (EC) is associated with high morbidity rates. Tight glycemic control using an artificial pancreas (AP) is one of the promising strategies to reduce postoperative inflammation and morbidities. However, the effects of tight glycemic control using AP in patients with EC are yet to be fully elucidated. METHOD: This study reviewed 96 patients with EC who underwent subtotal esophagectomy. The postoperative inflammation parameters and morbidity rates were compared between patients who used the AP (n = 27) or not (control group, n = 69). AP is a closed-loop system that comprises a continuous glucose monitor and an insulin pump. RESULTS: The numbers of white blood cells (WBC) and Neutrophils (Neut) were noted to be lower in the AP group than in the control group, but with no significant difference. The ratio in which the number of WBC, Neut, and CRP on each postoperative day (POD) was divided by those tested preoperatively was used to standardize the results. The ratio of WBC and Neut on 1POD was significantly lower in the AP group than in the control group. The rate of surgical site infection was lower in the AP group than in the control group. CONCLUSION: AP significantly decreased WBC and Neut on 1POD; this suggests the beneficial effects of AP in alleviating postoperative inflammation.

Prognostic relevance of tumor-resident memory T cells in metastatic lymph nodes of esophageal squamous cell carcinoma.

Tumor-resident memory T (TRM ) cells in primary tumors are reportedly associated with a favorable prognosis in several malignancies. However, the behaviors and functions of TRM cells in regional lymph nodes (LNs) of esophageal cancer remain poorly understood. The aim of this study was to elucidate the effects of TRM cells in regional LNs of esophageal cancer on clinicopathological findings and prognosis. Specimens of esophageal cancer and primary metastatic LNs (recurrent nerve LNs) were obtained from 84 patients who underwent radical esophagectomy between 2011 and 2017. We performed immunohistochemistry to enumerate and analyze TRM cells, and used flow cytometry to investigate the function of TRM cells. TRM cells were observed in both metastatic LNs and primary tumors. TRM cell-rich specimens exhibited reduced lymphatic invasion and LN metastasis and prolonged survival compared with TRM cell-poor specimens. TRM cells in metastatic LNs were more significantly associated with enhanced survival than TRM cells in primary tumors. TRM cells expressed high levels of granzyme B as a cytotoxicity marker. Our results suggested that high TRM cell infiltration in metastatic LNs improves survival even though LN metastasis is commonly associated with poor prognosis. TRM cells possibly contribute to antitumor immunity in regional LNs.

Significance of CD103+ tissue-resident memory T cells for predicting the effectiveness of immune checkpoint inhibitors in esophageal cancer.

BACKGROUND: Immune checkpoint inhibitors (ICIs), including nivolumab, have been approved to treat esophageal cancer. However, these remedies are not fit for all patients with esophageal cancer; therefore, a predictive surrogate marker is needed to assess their effectiveness. CD103+CD8+ tumor-infiltrating lymphocytes, defined as tissue-resident memory T cells (TRM), are promising indicators of response to ICIs, but it remains to be elucidated. This study investigated the association between the efficacy of ICIs and TRM. METHODS: The relationships between TRM infiltrating esophageal cancer, clinicopathological features, and prognosis after nivolumab initiation were examined using immunostaining. Tissue samples were obtained from surgically resected specimens of 37 patients with esophageal cancer who received nivolumab as a secondary or subsequent therapy. In addition, TRM infiltration was compared with programmed death-ligand 1 (PD-L1) expression and blood count parameters as predictors of nivolumab effectiveness. RESULTS: TRM-rich patients had a significant survival benefit after nivolumab initiation (12-months overall survival 70.8% vs 37.2%, p = 0.0485; 12-months progression-free survival 31.2% vs 0%, p = 0.0153) and experienced immune-related adverse events more frequently than TRM-poor patients (6 vs 2 patients). TRM infiltration was weakly correlated with PD-L1 positivity (r = 0.374, p = 0.022), but TRM may indicate more sensitive response to ICIs than PD-L1 expression in this study. Some blood test parameters also weakly correlated with TRM but did not impact prognosis. CONCLUSIONS: TRM-rich patients have a favorable prognosis after nivolumab initiation. Our results suggest that TRM are vital for antitumor immunity and are a promising predictor of ICIs effectiveness.

The Evaluation of Sarcopenia before Neoadjuvant Chemotherapy Is Important for Predicting Postoperative Pneumonia in Patients with Esophageal Cancer.

INTRODUCTION: Sarcopenia is often observed in patients with esophageal cancer (EC). However, the influence of sarcopenia during neoadjuvant chemotherapy (NAC) on complications has not been fully investigated. Thus, we aimed to investigate the best way of evaluating sarcopenia for predicting complications, especially postoperative pneumonia (PP), in patients with EC undergoing NAC and esophagectomy. METHODS: We retrospectively reviewed 113 patients. The skeletal muscle mass index (SMI) was evaluated by bioelectrical impedance analysis and/or computed tomography. Patients were diagnosed with sarcopenia at pre-NAC and preoperative timing. Different criteria were compared in terms of the predictability of PP. Next, we evaluated which factors were related to sarcopenia with the best PP predictability. RESULTS: Fifteen (13.2%) patients developed grade III or higher PP. Pre-NAC modified European Working Group on Sarcopenia in Older People (EWGSOP) criteria showed the highest sensitivity (100%) and acceptable specificity (75.8%) for predicting PP. Low pre-NAC body mass index and %VC were significantly associated with sarcopenia by the modified EWGSOP criteria. CONCLUSION: Pre-NAC sarcopenia by modified EWGSOP was a significant predictor of PP after esophagectomy. Appropriate interventions for these patients should be explored to prevent PP.

[The Role of Cancer-Associated Fibroblasts in Modulating Tumor Immunity in Colorectal Cancer].

Cancer-associated fibroblasts(CAFs)remodel the extracellular matrix(ECM)and shape the tumor microenvironment (TME), resulting in immune escape and the promotion of tumor metastasis. Using an orthotopic tumor model of colorectal cancers(CRCs)in mice, we demonstrated that the single-cell RNA sequencing of orthotopic rectal tumors identified a subpopulation of CAFs that modulate the immune response. In this review, we report that understanding the role of CAFs in the TME concerning tumor immunity may lead to future avenues for CAF-targeted therapy.

[A Case of Advanced Recurrent Rectal Cancer Successfully Treated by Rechallenge Therapy with an Anti-Epidermal Growth Factor Receptor(EGFR)Drug].

The patient was a 75-year-old man who had undergone potentially curative surgery for Stage Ⅲb rectal cancer followed by resection of liver metastases. Two years after the resection of liver metastases, lung and remnant liver metastases were found. He received chemotherapy for unresectable metastatic tumors. Based on the findings of molecular and pathological examinations(RAS: wild type; BRAF: wild type; MSI: negative; HER2: negative), the following chemotherapy regimens were administered: first-line, FOLFIRI plus panitumumab(PANI); second-line, mFOLFOX6; third-line, trifluridine/tipiracil; fourth- line, regorafenib. After fourth-line treatment, he was judged to have disease progression due to the increase in his lung and liver metastases and the elevation of tumor markers. All standard regimens were refractory, but the Eastern Cooperative Oncology Group performance status was zero and a liquid biopsy for RAS still showed wild type. Therefore, rechallenge therapy with anti-epidermal growth factor receptor(EGFR)drugs, cetuximab(CET)and irinotecan(IRI), was administered 13 months after the final course of FOLFIRI plus PANI treatment. After 4 courses of CET plus IRI, the size of the 2 metastatic tumors markedly decreased and his tumor marker levels normalized.

[A Case of Robot-Assisted Abdominoperineal Resection Alongside En Bloc Prostatectomy and Vesico-Urethral Anastomosis for Local Recurrence].

A 66-year-old man presenting with cStage Ⅲc rectal cancer underwent laparoscopic low anterior resection(D3 lymph node dissection and R0 resection)following neoadjuvant chemoradiotherapy(capecitabine, 45 Gy/25 Fr)and received adjuvant chemotherapy(CAPOX). A year after surgery, abdominal contrast-enhanced computed tomography revealed recurrence near the rectal anastomosis with prostate invasion. The patient underwent robot-assisted abdominoperineal resection alongside en bloc prostatectomy and vesico-urethral anastomosis after 12 courses of neoadjuvant chemotherapy(FOLFIRI and panitumumab). He exhibited a good postoperative course and was discharged on the 12th postoperative day. After 7 months of surgery, no recurrence was observe; and urinary incontinence seen immediately after surgery gradually improved.

[A Case of Late Recurrence of Anal Canal Carcinoma after Surgery, Discovered following the Diagnosis of a Subcutaneous Tumor in the Perineal Region].

We present an 82-year-old male patient who underwent laparoscopic abdominal perineal rectal amputation and D3 lymph node dissection, including left inguinal lymph node dissection for anal canal carcinoma. Left inguinal lymph node metastasis was positive, and pT1bN2aM0, pStage Ⅲa was the final pathological diagnosis. He underwent 8 courses of capecitabine plus oxaliplatin therapy as adjuvant chemotherapy. He was examined without recurrence for 5 years postoperatively. However, he awared a perineal subcutaneous tumor and was transferred to our hospital for further examination and treatment 6 years postoperatively. Recurrence after anal canal carcinoma surgery was diagnosed based on a needle biopsy, and perineal subcutaneous tumor resection was performed. This is a rare case of late postoperative recurrence of anal canal carcinoma, which was detected due to a perineal subcutaneous tumor 6 years after surgery for anal canal carcinoma.

Significance of tumor heterogeneity of p-Smad2 and c-Met in HER2-positive gastric carcinoma with lymph node metastasis.

BACKGROUND: Tumor heterogeneity has frequently been observed in gastric cancer (GC), but the correlation between patients' clinico-pathologic features and the tumoral heterogeneity of GC-associated molecules is unclear. We investigated the correlation between lymph node metastasis and the intra-tumoral heterogeneity of driver molecules in GC. MATERIALS AND METHODS: We retrospectively analyzed the cases of 504 patients who underwent a gastrectomy at the Department of Gastroenterological Surgery, Osaka Metropolitan University and 389 cases drawn from The Cancer Genome Atlas (TCGA) data. We performed a clustering analysis based on eight cancer-associated molecules including HER2, c-Met, and p-Smad2 using the protein expression revealed by our immunohistochemical study of the patients' and TCGA cases. We determined the correlations between HER2 expression and the other molecules based on the degree of lymph node metastasis. RESULTS: Immunohistochemical staining data showed that a 43 of the 504 patients with GC (8.5%) were HER2-positive. In the HER2-positive cases, the expressions of c-Met and p-Smad2 were increased in accord with the lymph-node metastatic level. The overall survival of the HER2-positive GC patients with both p-Smad2 and c-Met expression was significantly (p = 0.030) poorer than that of the patients with p-Smad2-negative and/or c-Met-negative expression. The results of the TCGA data analysis revealed that 58 of the 389 GC cases (14.9%) were ERBB2-positive. MET expression was more frequent in the N1 metastasis group than the N0 group. In the high lymph-node metastasis (N2 and N3) group, SMAD2 expression was more frequent, as was ERBB2 and MET expression. CONCLUSION: p-Smad2 and c-Met signaling might play important roles in lymph node metastasis in HER2-positive GC.

Clinical relevance of tertiary lymphoid structures in esophageal squamous cell carcinoma.

BACKGROUND: Tertiary lymphoid structures (TLSs) have been reported to be involved in immune responses in many carcinomas. This study investigated the significance of TLSs in esophageal squamous cell carcinoma, focusing on TLS maturation.  METHODS: The relationships of TLSs with clinicopathological features of 236 patients who underwent curative surgery for stage 0-IV esophageal squamous cell carcinoma were investigated. Mature TLSs, in which the germinal center formation was rich in CD23+ cells, were classified as TLSs containing a germinal center (GC-TLSs). GC-TLS densities were measured, and CD8+ cells were counted. The prognostic impact of GC-TLSs was assessed by Kaplan-Meier plots using the log-rank test for the relapse-free survival. A comparative study of GC-TLSs was performed using the Wilcoxon rank sum test. The relationship between GC-TLSs and CD8+ cells was examined by Spearman's rank correlation coefficient test. RESULTS: TLSs were located mainly at the invasive margin of the tumor in cases with esophageal squamous cell carcinoma. Among the patients treated with neoadjuvant chemotherapy, those with advanced disease had a better prognosis in the GC-TLS high-density group than did those in the GC-TLS low-density group. Patients in whom neoadjuvant chemotherapy was effective had more GC-TLSs than those in whom it was less effective. The density of GC-TLSs and the number of tumor-infiltrating CD8+ cells were higher in patients treated with neoadjuvant chemotherapy than in those without chemotherapy, and a weak correlation between the density of GC-TLSs and the number of tumor-infiltrating CD8+ cells was observed. Moreover, co-culturing of PBMCs with an anticancer drug-treated esophageal squamous cell carcinoma cell line increased the CD20 and CD23 expression in PBMCs in vitro. CONCLUSION: TLS maturation may be important for evaluating the local tumor immune response in patients treated with neoadjuvant chemotherapy for esophageal squamous cell carcinoma. The present results suggest that TLS maturation may be a useful target for predicting the efficacy of immunotherapy, including immune checkpoint inhibitor treatment for esophageal squamous cell carcinoma.

[A Case of Late Recurrence of Esophageal Cancer, 15 Years after Surgery].

A 79-year-old man who underwent radical surgery for esophageal cancer in 2006, returned to our hospital in 2021 with a complaint of swelling in the right side of the neck. He was diagnosed with postoperative recurrence of esophageal cancer in the right cervical lymph node. In this study, we report a case of a late recurrence of esophageal cancer in which metastatic recurrence was observed 15 years after surgery. A detailed discussion of previous literature is additionally included.

Tertiary lymphoid structures show infiltration of effective tumor-resident T cells in gastric cancer.

Several studies have reported that tissue-resident memory T cells (TRM cells) or tertiary lymphoid structures (TLSs) are associated with a good prognosis. The aim of this study was to clarify the association of TRM cells and TLSs in the tumor immune microenvironment in gastric cancer (GC). We performed immunohistochemical and immunofluorescence staining to detect the presence of CD103+ T cells and to assess the association between CD103+ T cells and TLSs. CD103+ T cells were observed in the tumor epithelium accompanied by CD8+ T cells and were associated with a better prognosis in GC. Furthermore, CD103+ T cells were located around TLSs, and patients with CD103high had more rich TLSs. Patients who had both CD103high cells and who were TLS-rich had a better prognosis than patients with CD103low cells and who were TLS-poor. Moreover, for patients who received PD-1 blockade therapy, CD103high and TLS-rich predicted a good response. Flow cytometry was performed to confirm the characteristics of CD103+ CD8+ T cells and showed that CD103+ CD8+ T cells in GC expressed higher levels of PD-1, granzyme B, and interferon-γ than CD103- CD8+ T cells. Our results suggested that CD103+ CD8+ cells in GC are correlated with TLSs, resulting in enhanced antitumor immunity in GC.

A Randomized Phase II Study to Evaluate Prolonged Prophylactic Antibacterial Drug Treatment for Patients with Elevated Drain Amylase Concentration After Gastrectomy with D2 Lymph Node Dissection (REDUCED2).

INTRODUCTION: After D2 gastrectomy for advanced gastric cancer, patients with a high drainage fluid amylase level (d-AMY) on the first postoperative day (1POD) have an especially high risk of severe abdominal infectious complications (AICs), which could be fatal. On the hypothesis that prolonged antibiotic administration could reduce the incidence of severe AICs, we conducted a randomized phase II study to evaluate the optimal treatment duration of prophylactic antibiotics for patients who underwent D2 gastrectomy and had elevated d-AMY on 1POD. METHODS: Patients whose d-AMY was >3000 IU/L on 1POD after D2 gastrectomy for gastric cancer were randomly assigned to normal prophylactic antibiotic treatment given only on the day of surgery (Group A) or to prolonged antibiotic treatment given for 1 week after surgery (Group B). The primary endpoint was the incidence of severe AICs (Clavien-Dindo grade IIIa or higher). This trial was registered as UMIN000012152. RESULTS: This study was started in December 2013 and stopped in February 2019 because of poor patient accrual. Finally, 35 and 37 patients were assigned to groups A and B, respectively. The incidences of AICs were 22.9% (eight of 35) in group A and 13.5% (five of 37) in group B. One-sided P value of the Fisher exact test was 0.234. No adverse reactions to antibiotic prophylaxis were observed in any of the patients. CONCLUSIONS: Prolonged prophylactic antibiotic administration had a marginal benefit in preventing grade III or higher AICs and caused no treatment-related morbidities.

The Optimal Definition of Sarcopenia for Predicting Postoperative Pneumonia after Esophagectomy in Patients with Esophageal Cancer.

BACKGROUND: Esophageal cancer (EC) is associated with malnutrition in the vast majority of patients, and this often leads to sarcopenia, which is characterised by loss of skeletal muscle mass (SMM). Although sarcopenia could be one of the risk factors for postoperative pneumonia (PP), the optimal definition of sarcopenia using skeletal muscle mass index (SMI) by bioelectrical impedance analysis (BIA) remains unknown for predicting PP after esophagectomy in patients with EC. Therefore, this study aimed to identify high-risk patients for PP after esophagectomy through evaluating SMI by BIA and set an appropriate cut-off value for this purpose. METHOD: A total of 73 patients with EC who underwent subtotal esophagectomy with lymph node dissection at Osaka City University Hospital between 2017 and 2019 were reviewed retrospectively. The association between PP and perioperative factors including SMI by BIA were analysed. When SMI was lower than the cut-off values proposed by two study groups (Asian Working Group for Sarcopenia (AWGS) and original European Working Group on Sarcopenia in Older People (EWGSOP)) or SMM was less than 90% of standard, the patient was diagnosed with sarcopenia. Receiver operating characteristic analysis was performed to set the appropriate cut-off value of SMI, and a new criterion (modified EWGSOP) was formulated by using the value. Clinicopathological factors and postoperative complications between sarcopenia and non-sarcopenia groups were compared, which were classified by four different criteria: (1) AWGS, (2) original EWGSOP, (3) < 90% standard and (4) modified EWGSOP criteria. RESULTS: Nine patients (12.3%) were with PP grade III or higher. Total SMI as well as body mass index (BMI), transthyretin and % vital capacity (%VC) were found to be significantly associated with PP (Clavien-Dindo grade ≥ III). BMI, total and appendicular SMI of sarcopenic patients were found to be lower than those of non-sarcopenic patients. Low serum albumin and %VC were significantly associated with sarcopenia defined by modified EWGSOP criteria. The rate of PP was significantly higher in sarcopenic patients when the original and modified EWGSOP criteria were used (p = 0.0079 and 0.0015, respectively). A multivariate analysis revealed that sarcopenic state by modified EWGSOP criteria was the significant independent predictive factor of PP [p = 0.0031, hazard ratio (HR) = 10.1; 95% confidential interval (CI): 2.12-76.9]. CONCLUSION: Preoperative sarcopenia by modified EWGSOP criteria could be the best indicator using BIA for predicting PP after esophagectomy in patients with EC.

Preoperative C-reactive protein to albumin ratio predicts anastomotic leakage after esophagectomy for thoracic esophageal cancer: a single-center retrospective cohort study.

BACKGROUND: Postoperative anastomotic leakage (AL) is associated with not only prolonged hospital stay and increased medical costs, but also poor prognosis in esophageal cancer. Several studies have addressed the utility of various inflammation-based and/or nutritional markers as predictors for postoperative complications. However, none have been documented as specific predictors for AL in esophageal cancer. We aimed to identify predictors of AL after esophagectomy for thoracic esophageal cancer, focusing on preoperative inflammation-based and/or nutritional markers. METHODS: We retrospectively analyzed 295 patients who underwent radical esophagectomy for thoracic esophageal squamous cell carcinoma between June 2007 and July 2020. As inflammation-based and/or nutritional markers, Onodera prognostic nutritional index, C-reactive protein (CRP)-to-albumin ratio (CAR) and modified Glasgow prognostic score were investigated. Optimal cut-off values of inflammation-based and/or nutritional markers for AL were determined by receiver operating characteristic curves. Predictors for AL were analyzed by logistic regression modeling. RESULTS: AL was observed in 34 patients (11.5%). In univariate analyses, preoperative body mass index (≥ 22.1 kg/m2), serum albumin level (≤ 3.8 g/dL), serum CRP level (≥ 0.06 mg/dL), CAR (≥ 0.0139), operation time (> 565 min) and blood loss (≥ 480 mL) were identified as predictors of AL. Multivariate analyses revealed higher preoperative CAR (≥ 0.0139) as an independent predictor of AL (p = 0.048, odds ratio = 3.02, 95% confidence interval 1.01-9.06). CONCLUSION: Preoperative CAR may provide a useful predictor of AL after esophagectomy for thoracic esophageal squamous cell carcinoma.

[A Case of Hyperammonemic Encephalopathy following mFOLFOX6 plus Panitumumab Therapy for Rectal Cancer].

An 80-year-old man underwent laparoscopic rectal high anterior resection with perineal dissemination for the management of RS rectal cancer. Following the diagnosis of RS rectal cancer with muc, pT4a, N3(14/15), M1c, P1, pStage Ⅳc, RAS/BRAF: wild type, treatment was initiated with mFOLFOX6 plus panitumumab(Pmab). Laboratory examination on admission revealed mild renal dysfunction(Cr 1.45 mg/dL). The patient became confused on day 3 of chemotherapy(JCS Ⅲ-200). Furthermore, laboratory findings revealed a serum ammonia level of 338µg/dL. He was diagnosed with 5-FU- induced hyperammonemic encephalopathy. Discontinuation of high-dose 5-FU and branched-chain amino acid solutions improved his mental status and decreased serum ammonia levels. We switched his chemotherapy regime to CPT-11 plus Pmab, but it was discontinued after 1 course on his request.

[Effect of Upfront Dose Reduction in the First Cycle of Chemotherapy for Unresectable/Recurrent Gastric Cancers in Patients Aged Over 80 Years].

Chemotherapy for elderly patients requires ingenuity in treatment to mitigate its high risk. Therefore, we investigated an upfront dose reduction in the first cycle of chemotherapy for unresectable/recurrent gastric cancers in patients over 80 years old. We examined 6 patients over 80 years old, who underwent S-1 plus L-OHP therapy(SOX)for unresectable/recurrent gastric cancer in our department between January 2020 and January 2021. There were no adverse events over Grade 3 in the upfront dose reduction group(U group), while 1 case(50.0%)in the normal dose group(N group)experienced an adverse event over Grade 3. Moreover, only the U group continued treatment for 4 or more courses, whereas none from the N group did. Partial response(PR)was achieved as a therapeutic effect in 3 patients of the U group. Only 2 cases of the U group advanced to the second-line regimen and both were able to transition to the third-line regimen. However, none were able to even transition to the second-line regimen in the N group. Therefore, it was suggested that by reducing the dose of chemotherapy from the first cycle for elderly patients over 80 years old, the incidence of adverse events can be kept low, which makes it possible to continue long-term chemotherapy.

Circulating tumor cells with FGFR2 expression might be useful to identify patients with existing FGFR2-overexpressing tumor.

Fibroblast growth factor receptor (FGFR) is associated with proliferation, migration, and angiogenesis of carcinomas, and FGFR signaling inhibitors are considered a key drug for the treatment of solid tumors with FGFR overexpression. Amplification of FGFR2 is reportedly identified in 3%-10% of gastric cancers (GCs). The aim of this study is to clarify whether the identification of the circulating tumor cells (CTCs) with FGFR2 overexpression is useful to detect patients with FGFR2-overexpressing GC. One hundred GC patients who underwent gastrectomy were enrolled. A total volume of 8 mL of peripheral blood was collected from each patient just before gastrectomy, and mononuclear cells were enriched by Ficol density gradient centrifugation. These cells were immunostained with PI/CD45/EpCAM/FGFR2. The number of CTCs with FGFR2 expression in each sample was enumerated by FACScan. The FGFR2 expression level of the resected primary tumor was assessed by immunohistochemistry. The number of FGFR2-positive CTCs in the GC patients' peripheral blood was significantly correlated with the FGFR2 expression level of the primary GC. The relapse-free survival of the patients with FGFR2-positive CTCs (≥5 cells/10 mL blood) was significantly poorer (P = .018, log-rank) than that of the patients without FGFR2-positive CTCs (<5 cell/10 mL blood). These findings suggested that the determination of FGFR2-positive CTCs might help identify an existing tumor with FGFR2 overexpression.