Establishment and characterization of two novel patient-derived cell lines from giant cell tumor of bone: NCC-GCTB8-C1 and NCC-GCTB9-C1.

Giant cell tumor of bone (GCTB) is a rare osteolytic bone tumor consisting of mononuclear stromal cells, macrophages, and osteoclast-like giant cells. Although GCTB predominantly exhibits benign behavior, the tumor carries a significant risk of high local recurrence. Furthermore, GCTB can occasionally undergo malignant transformation and distal metastasis, making it potentially fatal. The standard treatment is complete surgical resection; nonetheless, an optimal treatment strategy for advanced GCTB remains unestablished, necessitating expanded preclinical research to identify appropriate therapeutic options. However, only one GCTB cell line is publicly available from a cell bank for research use worldwide. The present study reports the establishment of two novel cell lines, NCC-GCTB8-C1 and NCC-GCTB9-C1, derived from the primary tumor tissues of two patients with GCTB. Both cell lines maintained the hallmark mutation in the H3-3A gene, which is associated with tumor formation and development in GCTB. Characterization of these cell lines revealed their steady growth, spheroid-formation capability, and invasive traits. Potential therapeutic agents were identified via extensive drug screening of the two cell lines and seven previously established GCTB cell lines. Among the 214 antitumor agents tested, romidepsin, a histone deacetylase inhibitor, and mitoxantrone, a topoisomerase inhibitor, were identified as potential therapeutic agents against GCTB. Conclusively, the establishment of NCC-GCTB8-C1 and NCC-GCTB9-C1 provides novel and crucial resources that are expected to advance GCTB research and potentially revolutionize treatment strategies.

Establishment and characterization of NCC-ASPS2-C1: a novel patient-derived cell line of alveolar soft part sarcoma.

Alveolar soft part sarcoma (ASPS) is a rare mesenchymal tumor characterized by rearrangement of the ASPSCR1 and TFE3 genes and a histologically distinctive pseudoalveolar pattern. ASPS progresses slowly, but is prone to late metastasis. As ASPS is refractory to conventional chemotherapy, the only curative treatment is complete surgical resection. The prognosis of advanced and metastatic cases is poor, highlighting the need for preclinical research to develop appropriate treatment options. However, ASPS is extremely rare, accounting for < 1% of all soft tissue sarcomas, and only one patient-derived ASPS cell line is available from public cell banks worldwide for research. This study reports the establishment of a novel ASPS cell line derived from the primary tumor tissue of an ASPS patient, named NCC-ASPS2-C1. This cell line retains the ASPSCR1-TFE3 fusion gene, which is characteristic of ASPS. The characterization of this cell line revealed stable growth, spheroid formation, and invasive properties. By screening a drug library using NCC-ASPS2-C1, we identified several drugs that inhibited the proliferation of ASPS cells. In conclusion, the establishment of NCC-ASPS2-C1 provides a valuable resource for advancing ASPS research and developing novel treatments for this challenging disease.

Establishment and characterization of NCC-DFSP5-C1: a novel patient-derived dermatofibrosarcoma protuberans cell line.

Dermatofibrosarcoma protuberans (DFSP) is the most prevalent dermal sarcoma, characterized by the presence of the fusion of the collagen type I alpha 1 (COL1A1) gene with the platelet-derived growth factor beta chain (PDGFB) gene. Although PDGF receptor inhibitor imatinib mesylate was approved for the treating patients with unresectable or metastatic DFSP, disease progression was shown in 9.2% of the patients. Therefore, developing novel therapeutic strategies is crucial for improving the prognosis of DFSP. Patient-derived cell lines play a vital role in preclinical studies; however, only a limited number of DFSP cell lines are currently available in public cell banks. Here, we successfully established a novel DFSP cell line (NCC-DFSP5-C1) using surgically resected tumor tissue from a patient with DFSP. NCC-DFSP5-C1 cells were confirmed to carry the COL1A1-PDGFB translocation and maintain the same mutation as the original tumor tissue. They exhibited consistent growth, formed spheroids, and were invasive. By screening a drug library using NCC-DFSP5-C1 and four previously established DFSP cell lines, we identified anti-cancer drugs that inhibit DFSP cell proliferation. Our observations suggest that the NCC-DFSP5-C1 cell line holds promise as a valuable tool for conducting fundamental and preclinical studies for DFSP.

Patient vulnerability is associated with poor prognosis following upfront hepatectomy for colorectal liver metastasis.

BACKGROUND: With the rapid aging of populations worldwide, the number of vulnerable patients with liver metastasis from colorectal cancer has increased. This study aimed to examine the association between vulnerability and clinical outcomes in patients with colorectal liver metastasis (CRLM). METHODS: Consecutive 101 patients undergoing upfront hepatectomy for CRLM between 2004 and 2020 were included. The preoperative vulnerability was assessed using the Clinical Frailty Scale (CFS) score ranging from one (very fit) to nine (terminally ill), and frailty was defined as a CFS score of ≥ 4. A multivariable Cox proportional hazard regression model was utilized to investigate associations of frailty with disease-free survival (DFS), overall survival (OS), and cancer-specific survival (CSS). RESULTS: Of the 101 patients, 12 (12%) had frailty. Associations between frailty and surgical outcomes, namely, the incidence of 90-day mortality and postoperative complications, were not statistically significant (P > 0.05). In the multivariable analyses, after adjusting for clinical risk scores calculated using six factors (timing of liver metastasis, primary tumor lymph node status, number of liver tumors, size of the largest tumor, extrahepatic metastatic disease, and carbohydrate antigen 19-9 level) to predict recurrence following hepatectomy for CRLM, preoperative frailty was found to be an independent risk factor for DFS (hazard ratio [HR]:2.37, 95% confidence interval [CI] 1.06-4.72, P = 0.036), OS (HR:4.17, 95% CI 1.43-10.89, P = 0.011), and CSS (HR:3.49, 95% CI 1.09-9.60, P = 0.036). CONCLUSION: Preoperative frailty was associated with worse DFS, OS, and CSS after upfront hepatectomy for CRLM. Assessment and improvement of patient vulnerability may provide a favorable prognosis for patients with CRLM.

Establishment and characterization of NCC-LMS3-C1: a novel patient-derived cell line of leiomyosarcoma.

Leiomyosarcoma (LMS) is an aggressive mesenchymal malignancy, which originates from the smooth muscle cells or from the precursor mesenchymal stem cells that potentially differentiate into smooth muscle cells. LMS is one of the most common sarcomas. LMS has genomic instability, reflecting complex and unbalanced karyotypes, and the cytogenetic and molecular changes in LMS are not consistent. The standard treatment of the primary LMS is complete resection, and the metastasis is often observed even after curative surgery. Patient-derived cancer models are a key bioresource to develop a novel therapy, and we aimed to establish and characterize a novel cell line for LMS. We established a cell line from tumor tissues of the patient with LMS and named it NCC-LMS3-C1. We maintained NCC-LMS3-C1 cells for 12 months and passed them more than 30 times. Genome-wide copy number analysis demonstrated that NCC-LMS3-C1 cells harbored genetic abnormalities. NCC-LMS3-C1 cells exhibited aggressive phenotypes such as continuous growth, spheroid formation, and invasion in the tissue culture condition, which may reflect the clinical behaviors of LMS. We performed a drug screening using NCC-LMS3-C1 cells and found that four anti-cancer agents, such as bortezomib, dasatinib, mitoxantrone, and romidepsin, had remarkable anti-proliferative effects on NCC-LMS3-C1 cells. We conclude that NCC-LMS3-C1 cells will be a useful resource for the study of LMS.

Laparoscopic Extended Left Lateral Sectionectomy for Hepatocellular Carcinoma in a Patient with Right-Sided Ligamentum Teres: A Case Report and Literature Review.

Right-sided ligamentum teres (RSLT) is a rare anatomic variant in which the fetal umbilical vein connects to the right portal vein. Patients with RSLT frequently have hepatic vasculature and bile duct anomalies, which increase the risk of complications with hepatectomy. Most patients with RSLT undergo open hepatectomy. Herein, we describe a patient with RSLT and hepatocellular carcinoma who underwent laparoscopic hepatectomy. The patient was a 69-year-old man with hepatocellular carcinoma located in the left liver based on computed tomography (CT) and magnetic resonance imaging. Imaging also demonstrated RSLT. Three-dimensional CT analysis revealed independent right lateral type anomalies of the portal vein and bile duct. A laparoscopic extended left lateral sectionectomy was performed after careful surgical planning. Ultrasonography was used frequently during surgery to avoid damaging the right hepatic vasculature. The left lateral and partial left median sections were removed as planned. The patient's postoperative recovery was uneventful. Avoiding injury to the right hepatic vasculature is essential when performing left lobectomy, including left lateral sectionectomy, in patients with RSLT. Laparoscopic hepatectomy can be performed safely in patients with RSLT, provided that careful surgical planning is conducted using preoperative three-dimensional CT analysis and intraoperative ultrasonography.

Establishment and characterization of NCC-DFSP4-C1: a novel cell line from a patient with dermatofibrosarcoma protuberans having the fibrosarcomatous transformation.

Dermatofibrosarcoma protuberans (DFSP) is a superficial low-grade sarcoma, genetically characterized by a fusion gene in collagen type I α (COL1A1) gene and platelet-derived growth factor subunit ß (PDGFB). DFSP is locally aggressive and does not typically metastasize. However, DFSP with fibrosarcomatous transformation, which occurs in 7-16% of DFSP cases, demonstrates a poor prognosis than classic DFSP with a higher local recurrence rate and metastatic potential. Although imatinib, a PDGF receptor inhibitor, is a potent therapeutic agent for classic DFSP, it is less effective for DFSP with fibrosarcomatous transformation. The development of definitive chemotherapies for DFSP with fibrosarcomatous transformation is required. Patient-derived tumor cell lines are indispensable tools for preclinical research to discover novel therapeutic agents. However, only seven cell lines were derived from DFSP, out of which only two were established from DFSP with fibrosarcomatous transformation. Hence, in the present study, we established a novel DFSP cell line, NCC-DFSP4-C1, from a surgically resected DFSP tumor specimen with fibrosarcomatous transformation. NCC-DFSP4-C1 harbored an identical COL1A1-PDGFB fusion gene as its donor tumor. NCC-DFSP4-C1 cells retained the morphology of their donor tumor and demonstrated constant proliferation, spheroid formation, and invasion capability in vitro. By screening a drug library, we found that bortezomib and romidepsin demonstrated the strongest suppressive effects on the proliferation of NCC-DFSP4-C1 cells. In conclusion, we report a novel cell line of DFSP with fibrosarcomatous transformation, and demonstrate its utility in the development of novel therapeutic agents for DFSP.

Prognostic value of 18F-fluorodeoxyglucose uptake in the bone marrow on pretreatment positron emission tomography/computed tomography in patients with esophageal cancer who underwent esophagectomy.

BACKGROUND: Increased 18F-fluorodeoxyglucose (FDG) uptake in the bone marrow (BM) on positron emission tomography/computed tomography (PET/CT) clinically reflects increased BM metabolism owing to systemic inflammation, bacterial infection, anemia, and cytokine-producing tumors. The association between FDG uptake in the BM and prognosis after esophagectomy for esophageal cancer has not been investigated. METHODS: This study included 651 patients who underwent PET/CT before any treatment and McKeown esophagectomy for esophageal cancer between June 2007 and August 2021. The pretreatment degree of FDG uptake in the BM was evaluated using a visual assessment criterion. Patients were divided into low- and high-FDG uptake groups. We retrospectively investigated whether the degree of FDG uptake in the BM was associated with clinicopathological and surgical backgrounds, blood parameters, and prognosis. RESULTS: High FDG uptake in the BM was significantly associated with elevated white blood cell and neutrophil counts, increased C-reactive protein levels, decreased hemoglobin, serum albumin, and total cholesterol levels. High FDG uptake in the BM was an independent predictor of worse overall survival in clinical stages 0-II esophageal cancer (hazard ratio, 2.27; 95% confidence interval, 1.097-4.695; P = 0.027). Worse overall survival was also associated with advanced age, low American Society of Anesthesiologists physical status, an advanced clinical stage, and high intraoperative blood loss. CONCLUSION: Increased FDG uptake in the BM on pretreatment PET/CT may be a surrogate indicator of various clinically disadvantageous backgrounds and may act as a predictor of poor prognosis after esophageal cancer surgery.

Establishment and characterization of NCC-DSM1-C1: a novel cell line derived from a patient with desmoid fibromatosis.

Desmoid fibromatosis (DSM) is a rare, locally aggressive mesenchymal tumor genetically characterized by mutations in the CTNNB1 gene. A local control rate of up to 65‒80% for DSM is achieved with multiple modality treatments, including watchful monitoring, radiation therapy, chemotherapy, and surgery. However, several variables, such as age < 30 years, extremity tumor location, and tumor size of > 10 cm in diameter, are associated with poor local control rates in patients with DSM. The definitive treatments for DSM have not been established. Therefore, it is necessary to develop novel treatments for DSM. Moreover, although patient-derived tumor cell lines are potent tools for preclinical research, no DSM cell lines have been reported. Therefore, this study aimed to establish and characterize a novel DSM cell line for preclinical studies on DSM. Herein, we established the first cell line derived from a patient with DSM exhibiting poor prognostic factors (27-year-old male patient with a DSM tumor of > 10 cm in diameter located at the lower extremity) and named it NCC-DSM1-C1. NCC-DSM1-C1 cells had a T41A mutation in CTNNB1 and exhibited constant proliferation, spheroid formation, and invasion capability in vitro. Screening of antitumor agents in NCC-DSM1-C1 cells showed that bortezomib and romidepsin are effective against DSM. In conclusion, we report the first officially characterized DSM cell line derived from a patient with DSM exhibiting factors associated with poor prognosis. We believe that NCC-DSM1-C1 cell line is a useful tool for developing novel treatments for DSM.

Prognostic impacts of categorized postoperative complications in surgery for gastric cancer.

BACKGROUND: Postoperative complications generally aggravate postoperative prognosis and are correlated with both cancer-specific death and death from other causes. METHODS: Subjects were 197 patients who underwent gastrectomy at Kyoto Chubu Medical Center. Cancer-specific survival (CSS) and non-CSS (NCSS) were compared between cases with and without complications. Major complications were classified into C-com and N-com groups based on their prognostic impact on CSS and NCSS, respectively. Uni- and multivariate analyses were conducted using clinicopathological factors. RESULTS: During the study period, 30 patients (15.2%) died from gastric cancer and 34 (17.3%) died from other causes. The incidence of postoperative complications was 16.8%. Sixteen patients with anastomosis leakage, pancreatic fistula, or organ/space surgical site infection had significantly poorer CSS, whereas 30 patients with pneumonia or passage obstruction had significantly poorer NCSS. These were defined as C-com and N-com cases, respectively. In the uni- and multivariate analyses, C-com was a significant prognostic factor for CSS (p = 0.002, p = 0.039) and N-com was a significant prognostic factor for NCSS (p < 0.0001, p = 0.004). C-reactive protein levels indicated intermediate and severe inflammation in N-com and C-com cases, respectively. CONCLUSION: In N-com cases, surgical stress caused disruption of essential organ function, whereas damage in C-com cases occurred mostly in the abdominal cavity but was a risk for cancer regrowth. Thus, different postoperative complications worsen patient prognosis after gastrectomy in different ways. To optimize surgical outcomes, improved selection of treatment strategies for different complication types may be important.

Establishment and characterization of NCC-PLPS2-C1: a novel cell line of pleomorphic liposarcoma.

Pleomorphic liposarcoma (PLPS) is a highly malignant subtype of liposarcoma. It is histologically characterized by the presence of pleomorphic lipoblasts and can be accompanied by morphological foci that demonstrate differentiation to other histological lineages. PLPS is rare and accounts for only 5% of all liposarcomas. PLPS exhibits poor prognosis; distant metastases develop in 30-50% of patients after curative surgical resection, tumor-associated mortality occurs in up to 50% of patients, and effective chemotherapies for PLPS have not been established. The histological accompaniment of other morphological foci is an important prognostic factor for PLPS, and the development of chemotherapies for PLPS considering the histological morphology is necessary. Patient-derived cancer cell lines are critical tools for basic and pre-clinical research to understand diseases and develop chemotherapies. However, only two PLPS-derived cell lines have been reported, and their donor tumor specimens did not histologically accompany morphological foci other than lipoblasts. Thus, there is a need to establish patient-derived PLPS cell lines from various histological morphologies. Here, we report a novel PLPS cell line from a tumor specimen that histologically accompanied pleomorphic and bone-forming foci, and named it NCC-PLPS2-C1. NCC-PLPS2-C1 cells demonstrated constant proliferation, spheroid formation, and invasion capability in vitro. Screening of antitumor agents in NCC-PLPS2-C1 cells showed that bortezomib, romidepsin, and trabectedin were effective against NCC-PLPS2-C1. In conclusion, we report the first PLPS cell line from a tumor specimen that was morphologically accompanied by pleomorphic and born-forming foci. We believe that NCC-PLPS2-C1 will be useful for the development of novel chemotherapies for PLPS.

[The Usefulness of RFA as a Conversion Therapy after Molecular Targeted Therapy for Advanced Hepatocellular Carcinoma-A Case of Long-Term Survival with Multidisciplinary Treatment].

In this study, we report a case in which molecular-targeted agents have been shown to be effective in the treatment of unresectable hepatocellular carcinoma(HCC), which has enabled a radical treatment, conversion therapy, and long-term survival with multimodality treatment including RFA. Case: A 61-year-old male, abdominal ultrasonography revealed a large liver tumor and multiple lesions mainly in the right lobe of the liver. He was diagnosed as having unresectable HCC, and treatment with sorafenib was initiated. After treatment, the tumor was clearly reduced in size and the lung metastases disappeared. Five years later, recurrence was observed at the treated site of S7/8, and RFA was performed again after TACE. The patient has survived for 8 years without recurrence.

The evaluation of the correlation between origami crane training and Fundamentals of Laparoscopic Surgery (FLS).

Objective: How does making origami cranes under a dry box affect Fundamentals of Laparoscopic Surgery (FLS) scores in medical students? Design: Four medical students from Asahikawa Medical University (tertiary hospital) participated. They made origami cranes under a dry box (origami crane training) five days per week for four weeks. The time required to make each origami crane (origami crane time) and degree of completion were evaluated. FLS scores were measured before training and on days 5, 10, 15, and 20. We examined the relationship between "origami crane training" and FLS scores. Results: At the beginning of the experiment, none of the participants could complete the origami crane, but they were able to complete it in 31 ± 7 min on day 20. The Total FLS score was 164 ± 48 before the start of training, and 1107 ± 112 on day 20. The average scores of the students closely approached the Proficiency Level for the FLS tasks of peg transfer, loop ligation and extracorporeal ligation (103→228, 61→137, 0→259). The change over time in the average of the increase in Total FLS Score (difference from the first time and each week's score) improved significantly in four weeks (P < 0.01). Conclusions: Origami crane training improved the medical students' FLS scores. We thought that origami crane training mainly enhanced hand-eye coordination and bi-hand coordination.

Lymphoepithelioma-like cholangiocarcinoma not associated with Epstein-Barr virus or hepatitis virus: case report and literature review of 100 reported cases.

Lymphoepithelioma-like cholangiocarcinoma (LEL-CC) is a type of lymphoepithelioma-like carcinoma (LELC) and a rare variant of primary liver tumor. Although it is uncommon and only 100 cases have been reported thus far, the number of reports has increased in recent years. LEL-CC reportedly occurs more frequently in Asian women; Epstein-Barr virus (EBV) and hepatitis viruses are both strongly associated with tumor development. Here, we describe a 76-year-old woman who exhibited LEL-CC not associated with EBV or hepatitis virus. She was referred to our department with a 3.0-cm × 2.8-cm tumor in the left lobe of the liver. Based on computed tomography and magnetic resonance imaging findings, the tumor was preoperatively diagnosed as hepatocellular carcinoma. Thus, we performed extended left hepatectomy with caudal lobectomy. Histopathological examinations revealed columnar tumor cells with atypical nuclei that proliferated in a cord-like or glandular tubular pattern with dense lymphocytic infiltration. Immunohistochemical analysis showed negative HepPar-1 and arginase findings, indicating non-hepatocyte origin; however, the biliary-type cytokeratins CK7 and CK19 were detected. Based on these findings, the tumor was identified as LEL-CC. EBV-encoded RNA in situ hybridization findings were negative; the patient's clinical characteristics were not suggestive of hepatitis virus infection. In conclusion, we suggest that clinicians consider LEL-CC as a differential diagnosis for liver tumors in Asian women, including patients without EBV or hepatitis virus.

Clinical Performance of the cobas Liat SARS-CoV-2 & Influenza A/B Assay in Nasal Samples.

BACKGROUND AND OBJECTIVE: Point-of-care type molecular diagnostic tests have been used for detecting SARS-CoV-2, although their clinical utility with nasal samples has yet to be established. This study evaluated the clinical performance of the cobas Liat SARS-CoV-2 & Influenza A/B (Liat) assay in nasal samples. METHODS: Nasal and nasopharyngeal samples were collected and were tested using the Liat, the cobas 6800 system and the cobas SARS-CoV-2 & Influenza A/B (cobas), and a method developed by National Institute of Infectious Diseases, Japan (NIID). RESULTS: A total of 814 nasal samples were collected. The Liat assay was positive for SARS-CoV-2 in 113 (13.9%). The total, positive, and negative concordance rate between the Liat and cobas/NIID assays were 99.3%/98.4%, 99.1%/100%, and 99.3%/98.2%, respectively. Five samples were positive only using the Liat assay. Their Ct values ranged from 31.9 to 37.2. The Ct values of the Liat assay were significantly lower (p < 0.001) but were correlated (p < 0.001) with those of other molecular assays. In the participants who tested positive for SARS-CoV-2 on the Liat assay using nasopharyngeal samples, 88.2% of their nasal samples also tested positive using the Liat assay. CONCLUSION: The Liat assay showed high concordance with other molecular assays in nasal samples. Some discordance occurred in samples with Ct values > 30 on the Liat assay.

A prospective clinical evaluation of the diagnostic accuracy of the SARS-CoV-2 rapid antigen test using anterior nasal samples.

INTRODUCTION: The diagnostic accuracy of antigen testing of anterior nasal (AN) samples for the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has not been evaluated in the Japanese population. This study assessed the diagnostic accuracy of the Roche SARS-CoV-2 rapid antigen test (rapid antigen test) using AN samples. METHODS: Two AN samples and one nasopharyngeal (NP) sample were collected from individuals undergoing screening for SARS-CoV-2 infection. The results of the rapid antigen test and the reverse-transcription polymerase chain reaction (RT-PCR) test using AN samples were compared to those of RT-PCR tests using NP samples. RESULTS: Samples were collected from 800 participants, 95 and 110 of whom tested positive for SARS-CoV-2 on RT-PCR tests of AN and NP samples, respectively. The overall sensitivity/specificity of the AN rapid antigen test and AN RT-PCR were 72.7%/100% and 86.4%/100%, respectively. In symptomatic cases, the sensitivities of the AN rapid antigen test and AN RT-PCR were 84.7% and 94.9%, respectively. In asymptomatic cases, the sensitivities of the AN rapid antigen test and AN RT-PCR were 58.8% and 76.5%, respectively. The sensitivity of the AN rapid antigen test was over 80% in cases with cycle threshold (Ct) values < 25; it significantly decreased with an increase in the Ct values (p < 0.001). CONCLUSION: The rapid antigen test with AN samples had a favorable sensitivity, especially in symptomatic cases or in cases with Ct values < 25. It gave no false-positive results. Compared with AN-RT PCR, the AN rapid antigen test had a modestly lower sensitivity in asymptomatic cases.

Peritoneal Recurrence of Cecal Cancer with Specific Imaging Findings and Shrinkage after Treatment with Pembrolizumab.

Pembrolizumab is one of the treatment options for treatment-refractory unresectable advanced or metastatic colorectal cancer with microsatellite instability-high (MSI-H) or deficiencies in DNA mismatch repair (dMMR). Herein, we report a case in which a recurrent cecal cancer lesion showed specific imaging findings and local inflammatory findings during treatment with pembrolizumab, followed by marked shrinkage. The patient was an 80-year-old woman. Postoperative peritoneal recurrence of cecal cancer of approximately 7 cm in size was observed. The patient had MSI-H and was treated with pembrolizumab. After five courses of treatment, the patient presented to our hospital with a chief complaint of abdominal pain. A blood test showed a strong inflammatory reaction, and computed tomography (CT) showed diffuse low-density area in the tumor. Under the suspicion of an abscess, conservative treatment was initiated and the patient quickly recovered. A CT at 1 month showed a marked reduction in size at the same site, and a CT at 3 months showed that the recurrent foci had almost disappeared. The inflammatory reaction before shrinkage in this case may have been caused by tumor immune response to pembrolizumab.

What are the factors predictive of postoperative complications in patients with colorectal cancer undergoing stenting as a bridge to surgery?

OBJECTIVE: Using a self-expanding metal stent as a bridge to surgery (BTS) is considered a reasonable strategy for patients with acute malignant large bowel obstruction. Since postoperative complications have a negative impact on patient survival, we aim to clarify the predictors of complications in patients undergoing BTS using a self-expanding metal stent. METHODS: We conducted a retrospective review of 61 patients with colorectal cancer (CRC) who underwent stenting as a BTS at our institution. We analyzed the association of postoperative complications with clinicopathologic, surgical, and patient factors, and with the prestenting or preoperative laboratory data. RESULTS: Both postoperative complications in general and severe complications were significantly associated with a longer stenotic-section length (p = 0.007 and p = 0.003), lower preoperative hemoglobin levels (p < 0.001 and p = 0.081), and lower prestenting hemoglobin levels (p = 0.006 and p = 0.042). Multivariate logistic regression analysis showed that lower prestenting (<13.0 g/dl) and preoperative (<11.5 g/dl) hemoglobin levels were independent predictive factors for postoperative complications (odds ratio [OR]: 4.15; 95% confidence interval [CI]: 1.07-18.90; p = 0.040; and OR: 4.93; 95% CI: 1.35-20.28; p = 0.016). A stenotic-section length of 5.0 cm or greater was predictive of severe complications (OR: 25.67; 95% CI: 1.95-1185.00; p = 0.011). CONCLUSIONS: Our data suggest that lower hemoglobin levels before stenting and a longer length of the stenotic section of bowel might predict postoperative complications in patients with CRC undergoing BTS for obstruction.

[Two Cases of Blind Pouch Syndrome after Total Gastrectomy].

Blind loop syndrome(BLS)is one of the complications that can occur after intestinal anastomosis. Patients with the syndrome present with various clinical features, including nutrient malabsorption caused by the blind end as a result of the anastomotic morphology. On the other hand, blind pouch syndrome(BPS)is a subtype of BLS. While it has a similar underlying mechanism, the clinical symptoms of patients with BPS are significantly different from those of patients with BLS; ie, the symptoms develop almost locally without nutrient malabsorption. There have been some reports that dealt with BPS as a disease that was distinct from BLS. Since conservative treatment cannot be expected to produce a curative effect in patients with BPS, it is necessary to administer surgical treatment in many cases. Previous studies have reported that resection of the blind pouch, which caused the local symptoms, was a curative surgical procedure for BPS. In the present study, we report 2 cases of BPS after Roux-en-Y reconstruction during total gastrectomy for gastric cancer patients, that were cured by surgical treatment by creating a bypass to the blind pouch.

[Safety of Pancreaticoduodenectomy in Patients of Advanced Age and Our Efforts to Prevent Postoperative Pneumonia].

With the aging of society, surgical patients are becoming older. The same trend can be seen in patients undergoing highly invasive operations, such as pancreaticoduodenectomy(PD). The risk of postoperative complications is reportedly higher in patients of advanced age, and postoperative pneumonia occurs at particularly high frequency. We investigated the safety of PD in patients of advanced age with a focus on the prevention of postoperative pneumonia. In total, 223 patients underwent PD at our department from January 2015 to December 2020. We compared various parameters between older patients(≥80 years of age, n=32)and younger patients(<80 years of age, n=191). Although older patients had lower nutrition scores, there was no significant difference in the incidence of postoperative complications between the two groups. Three older patients who were undergoing swallowing rehabilitation by a speech-language therapist did not develop postoperative pneumonia. However, one patient who did not receive swallowing rehabilitation developed postoperative pneumonia. Based on these findings, we plan to incorporate swallowing evaluation before postoperative oral intake into the clinical pathway and introduce speech-language therapy intervention in patients of advanced age.