佐田 尚宏

AIM: The clinical efficacy of chemoradiotherapy (CRT) is largely dependent on host immune status. The aim of this study was to identify possible markers expressed on circulating mononuclear cells to predict tumour response in patients with locally advanced rectal cancer (LARC). METHODS: Peripheral blood samples were obtained from 47 patients diagnosed with LARC before and after CRT. The numbers of lymphocytes and monocyte subsets were analysed using flow cytometry. Based on clinical and pathological findings, patients were classified as high or low responders. RESULTS: Lymphocyte counts were markedly decreased after CRT. Total numbers of lymphocytes (p = 0.030) and CD4(+) T cells (p = 0.041) in post-CRT samples were significantly lower in low responders than in high responders. In contrast, monocyte counts were not reduced and the number of CD14dim (+) CD16(+) nonclassical (patrolling) monocytes were somewhat increased after CRT (p = 0.050). Moreover, the ratios of programmed cell death ligand 1 (PD-L1) (+) cells on patrolling monocytes before and after CRT were significantly higher in low responders than in high responders (p = 0.0046, p = 0.0006). The same trend was observed for classical and intermediate monocytes. The expression of PD-L1 on patrolling monocytes before CRT correlated inversely with the number of T cells and natural killer (NK) cells after CRT. PD-L1(+) ratio in patrolling monocytes was an independent predictor for response to CRT. CONCLUSION: Programmed cell death ligand 1 (PD-L1) expression on patrolling monocytes suppresses cell-mediated immunity in patients receiving CRT which could be related to tumour response, and may be a useful biomarker for decision-making in the management of patients with LARC.

BACKGROUND: Chronic pancreatitis (CP) is defined according to the recently proposed mechanistic definition as a pathological fibro-inflammatory syndrome of the pancreas in individuals with genetic, environmental, and/or other risk factors who develop persistent pathological responses to parenchymal injury or stress. METHODS: The clinical practice guidelines for CP in Japan were revised in 2021 based on the 2019 Japanese clinical diagnostic criteria for CP, which incorporate the concept of a pathogenic fibro-inflammatory syndrome in the pancreas. In this third edition, clinical questions are reclassified into clinical questions, background questions, and future research questions. RESULTS: Based on analysis of newly accumulated evidence, the strength of evidence and recommendations for each clinical question is described in terms of treatment selection, lifestyle guidance, pain control, treatment of exocrine and endocrine insufficiency, and treatment of complications. A flowchart outlining indications, treatment selection, and policies for cases in which treatment is ineffective is provided. For pain control, pharmacological treatment and the indications and timing for endoscopic and surgical treatment have been updated in the revised edition. CONCLUSIONS: These updated guidelines provide clinicians with useful information to assist in the diagnosis and treatment of CP.

Background: The number of total pancreatectomy cases have increased worldwide, expanding the need for new insulin products and high-titer pancrelipases. However, the current data that is focused on hypoglycemic events after a total pancreatectomy from large nationwide series are still lacking. This study is aimed to assess the risk factors associated with hypoglycemic events after a total pancreatectomy. Methods: Data were prospectively collected from 216 consecutive patients who underwent total pancreatectomies between August 2015 and December 2017 from 68 Japanese centers. Of the 216 patients, 166 with a follow-up period of 1 year were analyzed. The risk factors for hypoglycemic events at 6 and 12 months (postoperative months 6 and 12) were investigated based on the results of a nationwide multicenter prospective study. Results: Of the 166 patients, 57 (34%) and 70 (42%) experienced moderate or severe hypoglycemic events or hypoglycemia unawareness on a monthly basis at postoperative months 6 and 12, respectively. Multivariate analysis revealed that body weight loss after surgery ≥0.3 kg and total cholesterol level ≤136 mg/dL at postoperative month 6, and glycated hemoglobin level ≤8.9% and rapid-acting insulin use at postoperative month 12 were independent risk factors for hypoglycemic events after a total pancreatectomy. There were different independent risk factors depending on the postoperative period. Conclusion: Patients with body weight loss after surgery, low total cholesterol level, strict glycemic control, and using rapid-acting insulin should be aware of the occurrence of hypoglycemic events after their total pancreatectomy. In order to prevent hypoglycemic events after a total pancreatectomy, we need to consider optimal nutritional and glycemic control according to the postoperative period.

肝移植領域でのエベロリムス(EVR)の使用経験例は少ない。またEVRは移植臓器である肝臓で代謝されることに加えて、初期投与量設定に用いる指標がないため速やかに目標血中濃度に到達させるのが難しい現状がある。今回、タクロリムス(Tac)の薬物動態に基づいたEVRの初期投与量設計の可能性を見出すため、自治医科大学附属病院におけるEARとTacの薬物動態の相関関係を検討した。方法として、EVRとTacの血中濃度(ng/mL)を1日投与量(mg/day)で除したC/D比を算出し、相関関係を後方視的に検討した。結果は患者間でEVRの1日投与量と血中濃度の相関関係はなく(r=0.3615、p=0.169)、EARとTacのC/D比に正の相関関係が得られた(r=0.7472、p<0.001)。肝移植症例におけるTacとEVRの薬物動態には相関関係があるため、今後、EVR投与量設計の参考になると思われた。(著者抄録)

肝移植後胆道合併症は依然として発症率が高く、予後に影響する重要な合併症である。胆道合併症は胆管狭窄、胆汁瘻に大別されるが、肝内結石はまれであり、とくに小児肝移植後肝内結石の診断・治療は確立されていない。小児肝移植症例の胆道再建は胆管空腸吻合がほとんどであるため、胆道合併症に対する治療は経皮経肝的胆道ドレナージ(PTBD)下カテーテル治療か外科的治療に限られていた。近年、ダブルバルーン小腸内視鏡(DBE)の改良とデバイスの進歩により、小児肝移植後胆道合併症においてもDBE下カテーテル治療が可能になってきている。低侵襲治療であるDBE下治療により、小児肝移植後肝内結石に対しても早期発見治療が可能となり、今後長期予後の向上が期待できる。(著者抄録)

INTRODUCTION: An eyeglass gaze camera and a skeletal coordinate camera without sensors attached to the operator's body were used to monitor gaze and movement during a simulated surgical procedure. These new devices have the potential to change skill assessment for laparoscopic surgery. The suitability of these devices for skill assessment was investigated. MATERIAL AND METHODS: Six medical students, six intermediate surgeons, and four experts performed suturing tasks in a dry box. The tip positions of the instruments were identified from video recordings. Performance was evaluated based on instrument movement, gaze, and skeletal coordination. RESULTS: Task performance time and skeletal coordinates were not significantly different among skill levels. The total movement distance of the right instrument was significantly different depending on the skill level. The SD of the gaze coordinates was significantly different depending on skill level and was less for experts. The expert's gaze stayed in a small area with little blurring. CONCLUSIONS: The SD of gaze point coordinates correlates with laparoscopic surgical skill level. These devices may facilitate objective intraoperative skill evaluation in future studies.

PURPOSE: Although neutrophil extracellular traps (NETs) are present in various tumors, their roles in tumor biology have not been clarified yet. In this study, we examined how NETs affect the pharmacokinetics and effects of doxorubicin (DOX). METHODS: NETs were generated by neutrophils stimulated with phorbol 12-myristate 13-acetate (PMA) or lipopolysaccharide (LPS). DOX was added to NETs and their distribution was observed under fluorescein microscopy, and the diffusion of DOX through 3 μM pores from lower to upper chambers was evaluated with a fluorescence-based assay. Ovarian cancer cells, KOC-2S and SKOV3, were embedded in collagen gel droplets and cultured in 3D way and their apoptosis was examined with flow cytometry. RESULTS: DOX was mostly co-localized with NETs. The transfer of DOX to upper chambers increased over time, which was significantly decreased by the presence of neutrophils stimulated with PMA or LPS in the lower chamber. DOX outside of the gel increased the rates of annexin V (+) apoptotic cells, which were significantly reduced by the addition of LPS-stimulated neutrophils in media both in KOC-2S and SKOV3. The reduced diffusion and apoptosis were mostly restored by the destruction of the NETs structure with 1000 u/ml DNAse I. CONCLUSION: NETs efficiently trap and inhibit the diffusion of DOX which may attenuate its ability to induce apoptosis of ovarian cancer cells. Degradation of NETs with DNAse I may augment the response of ovarian cancer to DOX.

Abstract Although preoperative chemoradiation therapy can down-stage locally advanced rectal cancer (LARC), it has little effect on distant metastases. Metformin exerts an anti-cancer effect partly through the activation of host immunity. LuM1, a highly lung metastatic subclone of colon 26, was injected subcutaneously (sc) in BALB/c mice and treated with metformin and/or local radiation (RT). Lung metastases and the primary tumors were evaluated and the phenotypes of immune cells in the spleen and lung metastases were examined with flow cytometry and immunohistochemistry. Local RT, but not metformin, partially delayed the growth of sc tumor which was augmented with metformin. Lung metastases were unchanged in metformin or RT alone, but significantly reduced in the combined therapy. The ratios of splenic T cells tended to be low in the RT group, which were increased by the addition of metformin. IFN-γ production of the splenic CD4(+) and CD8(+) T cells was enhanced and CD49b (+) CD335(+) activated NK cells was increased after combined treatment group. Density of NK cells infiltrating in lung metastases was increased after combination treatment. Metformin effectively enhances local and abscopal effects of RT though the activation of cell-mediated immunity and might be clinically useful for LARC.

BACKGROUND: Osteopenia is defined as low bone mineral density (BMD) and has been shown to be associated with outcomes of patients with various cancers. The association between osteopenia and perihilar cholangiocarcinoma is unknown. The aim of this study was to evaluate osteopenia as a prognostic factor in patients with perihilar cholangiocarcinoma. METHODS: A total of 58 patients who underwent surgery for perihilar cholangiocarcinoma were retrospectively analyzed. The BMD at the 11th thoracic vertebra was measured using computed tomography scan within one month of surgery. Patients with a BMD &lt; 160 HU were considered to have osteopenia and b BMD ≥ 160 did not have osteopenia. The log-rank test was performed for survival using the Kaplan-Meier method. After adjusting for confounding factors, overall survival was assessed by Cox's proportional-hazards model. RESULTS: The osteopenia group had 27 (47%) more females than the non-osteopenia group (p = 0.036). Median survival in the osteopenia group was 37 months and in the non-osteopenia group was 61 months (p = 0.034). In multivariable analysis, osteopenia was a significant independent risk factor associated with overall survival in patients with perihilar cholangiocarcinoma (hazard ratio 3.54, 95% confidence interval 1.09-11.54, p = 0.036), along with primary tumor stage. CONCLUSIONS: Osteopenia is associated with significantly shorter survival in patients with perihilar cholangiocarcinoma.

INTRODUCTION AND IMPORTANCE: Intussusception is invagination of the bowel and is rare in adults, representing only 5% of all cases of intussusception. Duodenal intussusception is also very rare. To the best of our knowledge, there is only one previous report of a malignant tumor in the fourth portion of the duodenum as the lead point of intussusception (Vaibhav et al., 2021 [1]). This reports a duodenal-duodenal intussusception caused by a malignant tumor in the third portion of the duodenum. CASE PRESENTATION: A 36-year-old woman with abdominal pain was diagnosed with duodenal intussusception by abdominal ultrasonography and computed tomography scan. Double balloon endoscopy showed that the intussusception had spontaneously reduced, and a tumor was found in the third portion of the duodenum. Open resection was performed because of the tumor location. Pathologic examination revealed adenocarcinoma with an adenoma of the duodenum. The patient had no evidence of recurrence for 4 years after resection. CLINICAL DISCUSSION: This patient had a primary duodenal malignancy and presented with intussusception, Duodenal intussusception is a rare condition requiring prompt intervention, usually requiring surgery. In this patient, since endoscopic resection was difficult, partial resection of duodenum was performed by open surgery assisted by double balloon enteroscopy. The pathological diagnosis of the resected specimen was primary duodenal malignancy. CONCLUSION: This is a report of adult duodenal intussusception caused by a primary duodenal malignancy. This rare condition posed an intriguing challenge for the optimal operative approach.

【目的】高度肥満症患者に対する減量・代謝改善手術症例の治療効果を検討する。【方法】2010年7月から2021年3月までに当院で行った107回(103症例)の減量・代謝改善手術を対象とした。主に体重変化と糖尿病治療効果を後ろ向きに評価した。【結果】99症例がデータ解析可能であった。術後総体重減少率は、術後1年目で28.4%、2年目で28.3%、5年目で27.3%であり、約30%の体重減少効果を認めた。糖尿病患者は47例であり、HbA1cの推移は術前の6.8%±1.4から術後6ヵ月で5.9%(±0.8)、術後1年で5.8%(±0.93)と改善を認めた。糖尿病寛解率は、術後6ヵ月で65.9%、術後1年で76.5%、術後4年で50.0%であり、糖尿病患者の半数で寛解を認めた。術前インスリン非使用群でインスリン使用群より糖尿病寛解率が良好な傾向が認められた。また、術前mABCDスコアが高い症例ほど術後寛解度が高かった。【結語】当院での減量・代謝改善手術症例において比較的良好な減量効果・糖尿病治療効果が得られた。(著者抄録)

BACKGROUND: Sinusoidal obstruction syndrome (SOS) after liver transplantation (LT) is a rare and potentially lethal complication. We retrospectively reviewed the outcomes of patients with post-transplant SOS. METHODS: Between May 2001 and December 2019, of 332 patients who underwent LT, 5 (1.5%) developed SOS. The median age at LT was 1.7 years (range 0.1-66.5). SOS was histopathologically diagnosed and classified as early-onset (<1 month) or late-onset. RESULTS: The median time to diagnosis of SOS was one month after LT. All patients developed acute cellular rejection before SOS, and the cause of SOS was acute cellular rejection in four patients and unknown in one. The treatment of SOS included conversion to tacrolimus from cyclosporine, intrahepatic hepatic vein stent placement, strengthening of immunosuppression, and plasma exchange. The 5-year graft survival rates in patients with and without SOS were 53.0% and 92.5%, respectively (p < 0.001). Of three patients with early-onset SOS, two patients improved and are doing well, and one patient died of graft failure four months after LT. CONCLUSIONS: The cause and treatment of post-transplant SOS are not yet defined. The poor outcomes in patients with early-onset SOS may be improved by strengthening of immunosuppression. Patients with late-onset SOS are ultimately treated by repeat LT.

BACKGROUND: Conventional therapies, including chemoembolization and radiation therapy, have been expected to prolong the prognosis of hepatocellular carcinoma (HCC) patients with extrahepatic metastases, which remains poor. However, little information is available on the efficacy of conventional therapies for such patients under tyrosine kinase inhibitor (TKI) treatment. METHODS: We retrospectively investigated 127 HCC patients with extrahepatic metastases, who were divided into the non-TKI (conventional therapies) and TKI groups and further subdivided into the TKI alone and TKI plus conventional therapies groups. Conventional therapies included transcatheter arterial chemoembolization, cisplatin-based chemotherapy, radiation, surgery, and UFT, an oral chemotherapeutic agent. RESULTS: The median of the overall survival (OS) of the 127 patients with extrahepatic metastases was 7.0 months. Meanwhile, the median OS of the TKI and non-TKI groups was 12.1 and 4.1 months, respectively. Imitating TKI after diagnosing metastases promoted a favorable increase in OS. Among the TKI group, the median OS in the TKI alone group was 8.9 months. TKI plus conventional therapies promoted no improvement in OS after adjusting for the patients' background data. CONCLUSION: TKI promoted a better OS in HCC patients with extrahepatic metastases compared to conventional therapies. However, TKI plus conventional therapies promoted no improvement in the prognosis of such patients.

BACKGROUND: There is no consensus about long-term outcomes in patients with biliary atresia. We retrospectively reviewed the long-term outcomes in pediatric patients who underwent living donor liver transplantation for biliary atresia. METHODS: Between May 2001 and December 2020, 221 (73%) of 302 pediatric patients who underwent living donor liver transplantation had biliary atresia. The median age at living donor liver transplantation was 1.2 (range 0.2-16.5) years, and follow-up was 10.3 ± 5.5 years. RESULTS: The 10-year graft survival rates in patients with and without biliary atresia were 94% and 89%, respectively (P = .019). The 10-year graft survival was significantly poorer in patients ≥12 years of age (84%) versus those <12 years of age at living donor liver transplantation (0-2 years: 95%; 2-12 years: 96%) (P = .016). The causes of graft failure in patients with biliary atresia included late-onset refractory rejection (n = 6), bowel perforation (n = 2), and acute encephalitis (n = 2), as well as cerebral hemorrhage, hepatic vein thrombosis, and sepsis (n = 1 for all). All 7 patients with graft failure due to refractory rejection and hepatic vein thrombosis underwent repeated liver transplantation and are alive in 2021. The rates of post-transplant portal vein complications and early-onset acute cellular rejection in patients with biliary atresia were higher than in those without biliary atresia (P = .042 and P = .022, respectively). In 2021, of 60 adolescents with biliary atresia, 14 (23%) reported medication nonadherence. The rate of liver dysfunction due to late-onset acute cellular rejection and graft failure due to late-onset refractory rejection in patients with nonadherence was higher than in patients with satisfactory adherence (P = .009). CONCLUSION: The long-term prognosis after living donor liver transplantation in pediatric patients with biliary atresia is quite good. However, long-term support to enhance medication adherence is required in adolescents with biliary atresia.