Intragraft B cell differentiation during the development of tolerance to kidney allografts is associated with a regulatory B cell signature revealed by single cell transcriptomics.

Mouse kidney allografts are spontaneously accepted in select, fully mismatched donor-recipient strain combinations, like DBA/2J to C57BL/6 (B6), by natural tolerance. We previously showed accepted renal grafts form aggregates containing various immune cells within 2 weeks posttransplant, referred to as regulatory T cell-rich organized lymphoid structures, which are a novel regulatory tertiary lymphoid organ. To characterize the cells within T cell-rich organized lymphoid structures, we performed single-cell RNA sequencing on CD45+ sorted cells from accepted and rejected renal grafts from 1-week to 6-months posttransplant. Analysis of single-cell RNA sequencing data revealed a shifting from a T cell-dominant to a B cell-rich population by 6 months with an increased regulatory B cell signature. Furthermore, B cells were a greater proportion of the early infiltrating cells in accepted vs rejecting grafts. Flow cytometry of B cells at 20 weeks posttransplant revealed T cell, immunoglobulin domain and mucin domain-1+ B cells, potentially implicating a regulatory role in the maintenance of allograft tolerance. Lastly, B cell trajectory analysis revealed intragraft differentiation from precursor B cells to memory B cells in accepted allografts. In summary, we show a shifting T cell- to B cell-rich environment and a differential cellular pattern among accepted vs rejecting kidney allografts, possibly implicating B cells in the maintenance of kidney allograft acceptance.

Indication for resection and possibility of observation for intraductal papillary mucinous neoplasm with high-risk stigmata.

BACKGROUND/OBJECTIVES: According to the revised international intraductal papillary mucinous neoplasm (IPMN) guidelines (2017), the indication for surgery is based on risk classification. However, some IPMNs with high-risk stigmata (HRS) can be observed for long periods without resection. Hence, we need to reconsider the risk stratification, and this study aimed to propose a novel risk stratification for HRS-IPMNs. METHODS: We enrolled 328 patients diagnosed with IPMN using endoscopic ultrasound between 2012 and 2019. We compared clinicopathological features between HRS and worrisome features (WF) and evaluated outcomes of HRS-IPMN. RESULTS: Fifty-three patients (HRS 38, WF 15) underwent resection at initial diagnosis and 275 patients were observed. Following observation for 30 months, 22 patients (17 HRS, 5 WF) underwent resection. Analysis of resected IPMNs (n = 75) revealed that HRS had dominantly pancreatobiliary mucin subtype. Pancreatobiliary-type IPMN had larger nodule sizes and lymphatic invasion and high recurrence with poor prognosis. Seventy-four patients were diagnosed with HRS, 55 underwent resection, and 19 continue to be observed. The resected group had larger nodule sizes (median 8 mm vs. 5 mm; P = 0.060), whereas the observed group had more main pancreatic duct (MPD) dilation (median 10 mm vs. 5 mm; P = 0.005). In the resected HRS group, only patients with MPD dilation ≥10 mm (n = 10) had no recurrence but had a favorable prognosis compared with those nodule size ≥5 mm (n = 45). CONCLUSIONS: Large nodule size may be associated with pancreatobiliary subtype and poor prognosis; however, patients with MPD dilation ≥10 mm with nodule size <5 mm did not require resection.

Clinical Impact of Portal Vein Distance on Computed Tomography for Postoperative Pancreatic Fistula after Pancreatoduodenectomy.

BACKGROUND: Pancreatic fistulas remain a significant concern after pancreatectomy owing to the associated high risk of mortality and high costs. It is not possible to perform preoperative risk stratification for all patients. This study aimed to evaluate the usefulness of the measurement of portal vein (PV) distance as a predictive indicator of pancreatic fistula development after pancreatoduodenectomy and compare it with the usefulness of other indicators such as body mass index (BMI), and abdominal fat area. METHODS: Patient characteristics, preoperative laboratory data, radiographic findings, and their association with pancreatic fistula development after pancreatoduodenectomy were analyzed for 157 patients who underwent resection during 2011-2017. Clinically relevant postoperative pancreatic fistulas (CR-POPF) were defined as Grade B or C fistulas based on the International Study Group of Pancreatic Surgery (ISGPS) 2016 consensus. RESULTS: CR-POPF developed in 38 patients (24.2%). Multivariate logistic regression indicated that PV distance and BMI were potential candidates for predictive models for pancreatic fistula development, and small pancreatic duct diameter, diabetes mellitus development, and pathology of non-pancreatic cancers were independent factors for CR-POPF. When comparing the two risk models (PV distance- and BMI-based models), the PV distance-derived risk model was compatible to the BMI-based stratification models (area under the curve 0.831 vs. 0.830). CONCLUSIONS: PV distance was confirmed to be a useful risk predictor for CR-POPF. This research highlighted the efficacy of abdominal thickness measurement, which is simple and easily applicable in the clinical setting.

Extra-adrenal pheochromocytoma with initial symptom of haemoptysis: a case report and review of literature.

BACKGROUND: Pheochromocytoma is a catecholamine-secreting tumour that leads to various symptoms. Haemoptysis is rarely caused by a pheochromocytoma occurring outside the bronchus or thoracic cavity. Here, we report the case of an extra-adrenal abdominal pheochromocytoma initially manifesting as haemoptysis/dyspnoea during exercise without classic symptoms. CASE PRESENTATION: A 22-year-old man with a history of severe dyspnoea experienced difficulties in breathing following a marathon owing to haemoptysis that required ventilator management 1 year before presentation. His father had undergone surgery for ectopic pheochromocytoma. Computed tomography (CT) revealed a 30-mm tumour between the inferior vena cava and pancreatic head while urinalysis revealed abnormally high noradrenaline levels. He was clinically diagnosed with an extra-adrenal abdominal ectopic pheochromocytoma. After controlling blood pressure, surgery was performed, and the tumour was successfully removed. Histopathology revealed chromogranin A (+), synaptophysin (+), S100 protein (+), and MIB-1 index of 1%. Therefore, the patient was finally diagnosed with extra-adrenal abdominal ectopic pheochromocytoma. CONCLUSIONS: Haemoptysis is a rare manifestation of abdominal ectopic paraganglioma. Prompt consideration of pheochromocytoma/paraganglioma when patients experience haemoptysis without any other possible aetiology may prevent inappropriate diagnosis and treatment and ultimately fatalities.

Combination of KRAS and SMAD4 mutations in formalin-fixed paraffin-embedded tissues as a biomarker for pancreatic cancer.

Formalin-fixed paraffin-embedded (FFPE) tissues used for routine pathological diagnosis are valuable for cancer genomic analysis; however, the association between mutation status derived from these specimens and prognosis in pancreatic ductal adenocarcinoma (PDAC) remains unclear. We analyzed 50 cancer-related gene mutations including driver genes in PDAC, using next-generation sequencing (NGS) to clarify the association between gene mutations and prognosis. DNA was extracted from FFPE tissues obtained from 74 patients with untreated resectable PDAC who underwent surgery at our institution between 2013 and 2018. Fifty of the 74 patients with DNA extracts from FFPE samples suitable for NGS were analyzed. The prevalence of driver gene mutations was as follows: 84% for KRAS, 62% for TP53, 32% for SMAD4, and 18% for CDKN2A. There were no cases of single SMAD4 mutations; its rate of coincidence with KRAS or TP53 mutations was 30% and 2%, respectively. The combination of KRAS and SMAD4 mutations resulted in significantly shorter relapse-free survival (RFS; median survival time [MST], 12.3 vs. 28.9 months, P = .014) and overall survival (OS; MST, 22.3 months vs. not reached, P = .048). On multivariate analysis, the combination of KRAS and SMAD4 mutations was an independent prognostic factor for RFS (hazard ratio [HR] 4.218; 95% confidence interval [CI], 1.77-10.08; P = .001) and OS (HR 6.730; 95% CI, 1.93-23.43; P = .003). The combination of KRAS and SMAD4 mutations in DNA obtained from FFPE tissues is an independent poor prognostic factor in PDAC.

Urgent distal pancreatectomy for intraperitoneal hemorrhage due to the spontaneous rupture of a pancreatic metastatic tumor from synovial sarcoma: a case report.

BACKGROUND: Synovial sarcoma is a soft tissue malignancy that frequently affects the extremities, adjacent to the large joints. Synovial sarcoma has a high rate of distant metastasis; however, pancreatic metastasis is extremely rare, and to our knowledge, there has been no report of bleeding due to spontaneous tumor rupture. This study reports the case of a patient with synovial sarcoma pancreatic metastasis causing tumor rupture and bleeding, which was successfully managed with emergent distal pancreatectomy. CASE PRESENTATION: A 27-year-old woman underwent extensive resection of the primary tumor and partial lung resection after chemotherapy for left femoral synovial sarcoma and multiple lung metastases 4 years prior. During the follow-up, a 35-mm tumor was noted in the pancreatic tail on abdominal computed tomography (CT), and no other distant metastases were detected via positron emission tomography CT. Laparoscopic distal pancreatectomy was scheduled for pancreatic metastasis of synovial sarcoma. However, before the scheduled pancreatectomy could be conducted, the patient visited the emergency department because of abdominal pain that occurred after consuming a small amount of alcohol, and CT showed ascites with high CT values and leakage of contrast media. She was diagnosed with intra-abdominal hemorrhage due to a ruptured metastatic pancreatic tumor, and an emergency operation was performed. In total, 1500 mL of blood was evacuated from the abdomen, and the bleeding pancreatic tail tumor was resected. Histopathological findings revealed synovial sarcoma metastasis and a ruptured tumor capsule, and tumor cells were observed in the hematoma. After discharge on postoperative day 18, the patient was carefully monitored and confirmed to be in relapse-free survival, without chemotherapy, at 6 months post-surgery. CONCLUSIONS: While the rate of tumor growth varies depending on the grade of the tumor, the possibility of rupture should be considered even in metastatic pancreatic tumors. In the case of pancreatic tumor rupture with stable circulation, radiological evaluation for oncology is necessary, and primary resection may be compatible with resectable cases.

The perioperative presepsin as an accurate diagnostic marker of postoperative infectious complications after esophagectomy: a prospective cohort study.

BACKGROUND: Presepsin is suggested to be an accurate sepsis diagnostic biomarker, playing an important role in distinguishing infection from no-infection status. However, to date, there is no study determining presepsin's role in diagnosing post-esophagectomy infectious complications. METHODS: Thirty patients who underwent esophagectomy for esophageal carcinoma were included in this prospective observational study. We investigated preoperative presepsin levels' changes and evaluated the relationship between infectious complications and presepsin levels. Moreover, we analyzed the classification and regression tree (CART) to determine presepsin's optimal cutoff values for discriminating infectious complications. RESULTS: For 10 patients with infectious complications, median presepsin levels were 168, 337, 303, 271, 314, 978, and 752 pg/ml, pre- and immediately post-surgery, and 1, 2, 3, 5, 7 days post-surgery, respectively. Presepsin levels were significantly higher in the infectious complication group exclusively from preoperation to POD 7 (p = 0.048). Furthermore, area under the curve's value of presepsin on POD 5 and 7 was higher than the other three biomarkers included for discriminating infectious complications (i.e., procalcitonin, leukocyte, and C-reacted protein). We set an optimal cutoff value for presepsin calculated by CART. Specifically, on POD 5, the cutoff was 888 pg/ml with a sensitivity of 60% and a specificity of 90%, and on POD 7, the cutoff was 668 pg/ml with a sensitivity of 60% and a specificity of 85%. CONCLUSIONS: Presepsin levels on POD 5 and 7 after esophagectomy are a valuable indicator of infectious complication's detection vs. leukocyte, C-reacted protein, and procalcitonin.

[A Case of Unresectable Advanced Rectal Cancer with a Pancreatic Tumor That Was Successfully Treated with FOLFIRINOX].

A 72-year-old man was admitted to our hospital department in September 2014 because of a positive fecal occult blood test.Colonoscopy showed a type 2 tumor in half of the AV 15 cm rectosigmoid colon.Histology of the biopsy indicated a moderately differentiated adenocarcinoma, and the RAS gene test found wild type.On CT examination, there were multiple liver lung metastases and a 30mm diameter tumor with pancreatic duct extension to the pancreatic body.A PET-CT examination had a high SUVmax at the same site.Because of the location of the tumor EUS-FNA was not used.However, the possibility of pancreatic body cancer could not be denied after the CT examination.Treatment by radical resection was impossible because of the spread of the cancer so we selected chemotherapy.Undeniable pancreatic metastasis of rectal cancer, pancreatic cancer was used as a prognostic factor as double cancer of rectal cancer and pancreatic cancer, from that UGT1A1 test side effects appearance was a low-risk decision, was selected FOLFIRINOX in the treatment regimen.After 25 cycles, the pancreatic body tumor and liver metastases and also the primary tumor were reduced, the multiple lung metastases disappeared, and disease control was good.Side effects were diarrhea on the day of administration of irinotecan, but this was controllable by administering oral loperamide when starting the infusion.Grade 3 or more peripheral neuropathy has not developed, and this regimen is continuing.Pancreatic cancer is a solid cancer with a poor prognosis; if you do not reach the tissue diagnosis of metastatic pancreatic cancer, was a case in which no choice but to select a regimen to carcinoma of the prognostic.

[A Case of Resection of Para-Aortic Lymph Node Recurrence and Peritoneal Recurrence Following Sigmoid Colon Cancer Surgery].

In June 2010, a 73-year old man diagnosed with sigmoid colon cancer underwent laparoscopic sigmoidectomy. The histopathological diagnosis was tub2, pSS, n (-), stageⅡ.Vascular invasion was present; however, at the patient's request, no adjuvant chemotherapy was administered.Computed tomography (CT) performed at the outpatient follow-up 4 years and 6 months after the surgery revealed a para-aortic lymph node metastasis in the caudal aspect of the left renal artery branch point. No other definite mass shadows were detected. Positron emission (PET)-CT revealed high tracer accumulation (SUVmax) not only in the CT-identified lymph node, but also near the site of the anastomosis in the bowel. Considering that no tracer accumulation was detected at any other sites and the patient's compliance with medication and scheduled visits was poor, surgical resection rather than chemotherapy was adopted as the treatment strategy. No metastases other than at the sites identified by the diagnostic imaging were found during the surgery. Since the findings on palpation did not rule out the possibility that the nodule near the anastomotic site was present inside the intestinal tract, lymph node dissection, resection of the intestinal tract including the anastomotic site, and re-anastomosis were performed. The most likely diagnosis based on the histopathological findings was dissemination for both the adenocarcinoma and the nodule near the anastomotic site. At present, the patient is being treated with adjuvant chemotherapy. In the Japanese Society for Cancer of the Colon and Rectum (JSCCR) Guidelines for the Treatment of Colorectal Cancer, the recommended therapeutic intervention is surgical resection of hematogenous metastases; however, no treatment is specified for lymph node metastases. In general, chemotherapy is administered for distant metastases. However, we have found no reports of cases in which a complete remission has been achieved. There are reports of improvement of survival by surgical resection in cases with solitary lymph node metastasis or isolated dissemination of colorectal cancer. These observations suggest that surgical therapy may have contributed to the improved prognosis in the present case.

[A Case of Advanced Breast Cancer in Which Marked Improvement of Joint Pain Was Obtained with Stepwise Dose Reduction of Trastuzumab Emtansine (T-DM1)].

A 51-year-old woman had previously received treatment for breast cancer at another hospital but had refused early and aggressive treatment. Therefore, she was treated with symptomatic therapy. As her disease progressed, the patient wished to receive palliative care, and was transferred to a palliative care hospital. However, based on her general condition, it was determined that aggressive treatment should not be abandoned, and she was referred to our hospital for treatment. During her initial visit, the patient was found to have left breast cancer with chest wall invasion, right breast metastasis, multiple liver and lung metastases, left pleural effusion accompanied by pleural dissemination, and left upper limb edema. There was no evidence of bone metastases. The patient's pain was managed with oral oxycodone sustained-release tablets (320 mg daily), using high-dose (80 mg) oral oxycodone hydrochloride hydrate as rescue medication. The results of immunohistochemical testing, confirmed by her previous hospital, were ER (-), PgR (-) and HER2/neu positive. First-line treatment was initiated with paclitaxel (PTX) plus trastuzumab (Tmab), and the response was rated as stable disease (SD). During the course of treatment, she developed drug-induced interstitial pneumonia, which was probably caused by the taxane. Therefore, the first-line treatment was discontinued and T-DM1 was initiated as second-line treatment. However, beginning with cycle 3 of the T-DM1 treatment, the patient began complaining of joint pain, mainly in the upper limbs. Therefore, the dose of oxycodone sustained-release tablets was increased to 600 mg per day. However, the patient's joint pain showed no improvement and it was considered unlikely that the pain was due to bone metastases. It was suspected that the pain was an adverse reaction to T-DM1, and the dose of T-DM1 was reduced by one step in cycle 7 of treatment. This resulted in a dramatic improvement of the patient's symptoms. Since oxycodone sustained-release tablets was being used at a high dose, sleepiness caused by the drug interfered with her activities of daily living. Consequently, as part of an opioid rotation scheme, topical fentanyl citrate was used concomitantly, and the initial daily oxycodone sustained-release tablets dose of 600 mg was reduced to 40 mg and administered in combination with fentanyl citrate (12mg). These findings suggest that uncontrollable joint pain can occur as an adverse reaction to T-DM1.

[Carcinoma of Unknown Primary Associated with a Sister Mary Joseph's Nodule--A Case Report].

A 72-year old woman visited our hospital complaining of an umbilical mass and a foul smell from the umbilical region. During the evaluation, a massive immobile tumor was palpated in the center of the lower abdomen in addition to an umbilical mass with necrosis. Computed tomography (CT) revealed a massive ovarian tumor accompanied by an umbilical tumor and cyst with peritoneal dissemination, metastases in the liver and spleen and a urachal tumor. There were no symptoms or imaging findings of gastrointestinal obstruction. While searching for the primary focus, it was determined that the ovarian tumor was not of ovarian origin. Under these circumstances, colonoscopy was the only remaining diagnostic modality. However, evaluation of the large intestine was impossible due to compression by the tumor, and diverticulosis of the sigmoid colon did not allow smooth insertion of the colonoscope. Therefore, an excisional biopsy of the umbilical tumor was performed. The most likely diagnoses based on the histopathological findings were colorectal cancer and urachal cancer. Therefore , mFOLFOX6 was selected for chemotherapy because it has been reported to be effective against both urachal and colorectal cancer. At the time of writing, good tumor control had been achieved in the lesions evaluated. Cases of Sister Mary Joseph's nodule have sporadically been reported. The most common primary foci for peritoneal metastases are the stomach, pancreas and ovary. However, in the present case, these sites were ruled out and the primary focus remained unidentified, making it difficult to select appropriate treatment. We present this case with a discussion of the literature.

Dysfunction of infiltrating cytotoxic CD8+ T cells within the graft promotes murine kidney allotransplant tolerance.

Tolerance of mouse kidney allografts arises in grafts that develop regulatory Tertiary Lymphoid Organs (rTLOs). scRNAseq data and adoptive transfer of alloreactive T cells post-transplant showed that cytotoxic CD8+ T cells are reprogrammed within the accepted graft to an exhausted/regulatory-like phenotype mediated by IFN-γ. Establishment of rTLOs was required since adoptive transfer of alloreactive T cells prior to transplantation results in kidney allograft rejection. Despite intragraft CD8+ cells with a regulatory phenotype, they were not essential for the induction and maintenance of kidney allograft tolerance since renal allotransplantation into CD8 KO recipients resulted in acceptance and not rejection. Analysis of scRNAseq data from allograft kidneys and malignant tumors identified similar regulatory-like cell types within the T cell clusters and trajectory analysis showed that cytotoxic CD8+ T cells are reprogrammed into an exhausted/regulatory-like phenotype intratumorally. Induction of cytotoxic CD8+ T cell dysfunction of infiltrating cells appears to be a beneficial mechanistic pathway that protects the kidney allotransplant from rejection through a process we call "defensive tolerance." This pathway has implications for our understanding of allotransplant tolerance and tumor resistance to host immunity.

Association Between Clinical Backgrounds and Malignant Progression of Suspected Intraductal Papillary Mucinous Neoplasm.

OBJECTIVES: Some intraductal papillary mucinous neoplasms (IPMNs) have malignant potential and can become pancreatic cancer. The mechanism behind the malignant progression of IPMN remains unknown. We aimed to identify the risk factors and interactions between backgrounds for IPMN. METHODS: We retrospectively enrolled 980 patients of pancreatic cancer or suspected IPMN (sIPMN) who underwent endoscopic ultrasound or retrograde cholangiopancreatography. We classified them into pancreatic cancer, high-risk sIPMN, and low-risk sIPMN, and investigated the risk factors for high-risk sIPMN. RESULTS: Smoking habits (odds ratio [OR], 3.74; 95% confidence interval [CI], 2.04-6.85; P < 0.001), serum carbohydrate antigen 19-9 ≥37 U/mL (OR, 6.30; 95% CI, 2.88-13.80; P < 0.001), and family history of cancers (OR, 2.38; 95% CI, 1.30-4.37; P = 0.005) were independent risk factors for high-risk suspected IPMN. Odds ratios of diabetes and neutrophil-to-lymphocyte ratio of 2.45 or greater were significantly higher in patients with a family history of cancer than those without a family history of cancer (OR, 3.28; 95% CI, 0.52-20.80 vs 1.85; 95% CI, 0.78-4.41; OR, 2.44; 95% CI, 0.81-7.34 vs 1.24; 95% CI, 0.67-2.30, respectively). CONCLUSIONS: Understanding the interactions between background factors can effectively prevent IPMNs' malignant transformation.

Usefulness of selective arterial calcium injection tests for functional pancreatic neuroendocrine tumors.

The selective arterial calcium injection (SACI) test is useful for patients with functional pancreatic neuroendocrine tumors (F-PNETs). This study evaluated which patients with F-PNETs would benefit from the SACI test. We retrospectively analyzed the preoperative findings of patients on computed tomography (CT), magnetic resonance imaging (MRI), CT angiography (CTA), and the SACI test. Fourteen patients who underwent pancreatectomy between January 1997 and September 2016 for F-PNETs were evaluated. We classified these patients into groups A, B, and C; group A, one tumor detected by either CT or MRI; group B, multiple tumors detected; and group C, the tumor location was accordant on CT, MRI, and CTA, but the SACI test revealed another tumor. In group A, the tumor was also detected by CTA and the SACI test was positive on calcium injection. In group B, the focus tumor among the multiple tumors was detected by the SACI test. In group C, another tumor was identified by the SACI test, whose location was different from that detected using CT and MRI. The SACI test is more useful for multiple F-PNETs on CT or MRI. If CT or MRI detects a single tumor, the SACI test or CTA may be unnecessary.

Diagnostic Utility of Presepsin in Infections After Liver Transplantation: A Preliminary Study.

BACKGROUND Infectious complications after solid organ transplantation can be fatal, and early diagnosis and intervention are important. To the best of our knowledge, no study has examined the diagnostic utility of presepsin, a known accurate biomarker, for infectious complications after liver transplantation. This study aimed to evaluate the utility of presepsin for detecting infection and perioperative kinetics of presepsin after liver transplantation. MATERIAL AND METHODS This single-institutional prospective, observational study included 13 patients who underwent living-donor or deceased-donor liver transplantation. Perioperative serum presepsin level was measured 6 times within a week to evaluate its association with infectious complications and compare it with procalcitonin and C-reactive protein levels and leukocyte count. Postoperatively, patients were followed up for 15 days for infectious complications. RESULTS Five of the 13 patients developed infectious complications after liver transplantation. The median time for infection diagnosis was 9 postoperative days (25th-75th percentile, 7-10). Presepsin levels on 5 and 7 postoperative days were significantly higher in patients with infection than in those without (P=0.019 and P=0.011, respectively). In receiver operating characteristic analysis, area under the curve values of presepsin on 5 and 7 postoperative days (0.881 and 0.905, respectively) were higher than those of other biomarkers. The optimal cut-off value of presepsin was 1361 pg/mL on postoperative day 5 and 1375 pg/mL on postoperative day 7. CONCLUSIONS Although this study included a small number of patients, presepsin levels on postoperative days 5 and 7 may be useful indicators for infectious complications after liver transplantation.

New strategy for evaluating pancreatic tissue specimens from endoscopic ultrasound-guided fine needle aspiration and surgery.

BACKGROUND AND AIM: Preoperative histological evaluation of pancreatic neoplasms is important for guiding the resection strategy and preventing postoperative adverse events. However, conventional endoscopic methods have technical limitations that reduce the accuracy of the histopathological examination. Probe electrospray ionization mass spectrometry (PESI-MS) may be a useful technique for rapidly evaluating small specimens. METHODS: This single-center prospective study included patients with pancreatic neoplasms between October 2018 and December 2019. Pancreatic ductal adenocarcinoma (PDAC) specimens were obtained via endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) and non-neoplastic tissue was obtained via surgery. Specimens were subjected to PESI-MS and the mass spectra were analyzed using partial least squares regression-discriminant analysis. RESULTS: The study included 40 patients with 20 nonneoplastic specimens and 19 PDAC specimens (1 case of neuroendocrine carcinoma was omitted). All nonneoplastic specimens were sufficient for PESI-MS analysis, although only 7 of 19 PDAC specimens were sufficient for PESI-MS analysis because of poor sample quality or insufficient quantity (<1 mg). Among the 27 analyzed cases, the mass spectra clearly differentiated between the PDAC and nonneoplastic specimens. CONCLUSIONS: This study revealed that PESI-MS could differentiate between PDAC and nonneoplastic specimens, even in cases where EUS-FNA produced very small specimens.

High risk pathogens and risk factors for postoperative pancreatic fistula after pancreatectomy; a retrospective case-controlled study.

BACKGROUND: Although the rates of surgical site infection are decreasing, surgical site infection after pancreatectomy remains frequent because of postoperative pancreatic fistula. Recent studies suggested a relationship between postoperative pancreatic fistula and pathogens cultured from drainage fluids after pancreatectomy. This study aimed to assess and evaluate high-risk pathogens cultured from postoperative drainage fluids for postoperative pancreatic fistulas or severe postoperative complications after pancreatectomy. MATERIALS AND METHODS: We retrospectively enrolled patients who underwent pancreaticoduodenectomy or distal pancreatectomy between 2012 and 2019. We assessed clinical characteristics and microbiological results of drainage cultures of pancreaticoduodenectomy or distal pancreatectomy patients, and we investigated the risk factors for clinically relevant postoperative pancreatic fistulas and Clavien-Dindo status using univariate and multivariate analyses. Finally, we detected high-risk pathogens from drainage cultures and analyzed the correlation between these pathogens and the severity of clinically relevant postoperative pancreatic fistula or Clavien-Dindo status. RESULTS: Four hundred and twenty-nine patients were enrolled: 257 underwent pancreaticoduodenectomy and 172 underwent distal pancreatectomy. Clinically relevant postoperative pancreatic fistulas and Clavien-Dindo status ≥ III were more frequently seen in pancreaticoduodenectomy patients than in distal pancreatectomy patients, namely grade C postoperative pancreatic fistula, which was observed in 19 pancreaticoduodenectomy patients. The most common pathogen found from drainage cultures was Enterococcus species, followed by Enterobacter species and Candida species. All pathogens were associated with clinically relevant postoperative pancreatic fistulas; however, Candida species was a dominant microorganism of clinically relevant postoperative pancreatic fistulas grade C, Clavien-Dindo status ≥ IV, and hemorrhage due to pseudoaneurysm. CONCLUSION: The presence of Candida species in the drainage fluid culture after pancreaticoduodenectomy can be a predictive factor of severe infectious complications, including postoperative pancreatic fistulas; thus, we should regularly collect cultures from drainage fluids and monitor for Candida infection.

A case of pancreatic hamartoma with characteristic radiological findings: radiological-pathological correlation.

Pancreatic hamartoma is a rare benign tumor. Its preoperative diagnosis is challenging. We present a case of pancreatic hamartoma whose radiological-pathological correlation was evaluated in detail. A 53-year-old man was referred to our institution for diagnosis and treatment. Contrast-enhanced computed tomography (CT) and magnetic resonance image revealed a 3.5 cm long tumor arising from the head of the pancreas with cystic and solid components, the latter of which was gradually and inhomogeneously enhanced in the delayed phase. Fluorodeoxyglucose (FDG) positron emission tomography/CT revealed slight FDG uptake in the solid component. Histologically, a number of pancreatic lobule-like structures, which were mainly composed of aggregates of small ducts embedded in concentric fibrous stroma with no apparent islets or peripheral nerves, were observed in the solid component, whereas multiple dilated ducts were seen in the cystic region. The solid component also contained a narrow area of edematous fibrous stroma with low vessel density, which corresponded with the unenhanced part in the inhomogeneously enhanced solid component. There was no remarkable cytological atypia throughout the mass. A pathological diagnosis of pancreatic hamartoma was made. The radiological findings agree well with the pathological findings. When a pancreatic tumor is of the solid type, preoperatively diagnosing it as pancreatic hamartoma is not possible. However, when a pancreatic tumor with cystic and solid components is inhomogeneously enhanced in contrast-enhanced studies, a diagnosis of pancreatic hamartoma can be considered.

Usefulness of 18 F-fluorodeoxyglucose positron emission tomography/computed tomography for predicting the prognosis and treatment response of neoadjuvant therapy for pancreatic ductal adenocarcinoma.

BACKGROUND: The Response Evaluation Criteria in Solid Tumors (RECIST) for computed tomography (CT) is preoperatively used to evaluate therapeutic effects. However, it does not reflect the pathological treatment response (PTR) of pancreatic ductal adenocarcinoma (PDAC). The Positron Emission Tomography Response Criteria in Solid Tumors (PERCIST) for positron emission tomography (PET)/CT is effective in other cancers. This study aimed to confirm the usefulness of PERCIST and the prognostic utility of PET/CT for PDAC. METHODS: Forty-two consecutive patients with PDAC who underwent neoadjuvant therapy (NAT) and pancreatectomy at our institution between 2014 and 2018 were retrospectively analyzed. We evaluated the treatment response and prognostic significance of PET/CT parameters and other clinicopathological factors. RESULTS: Twenty-two patients who underwent PET/CT both before and after NAT with the same protocol were included. RECIST revealed stable disease and partial response in 20 and 2 cases, respectively. PERCIST revealed stable metabolic disease, partial metabolic response, and complete metabolic response in 8, 9, and 5 cases, respectively. The PTR was G3, G2, and G1 in 8, 12, and 2 cases, respectively. For comparing the concordance rates between PTR and each parameter, PERCIST (72.7% [16/22]) was significantly superior to RECIST (36.4% [8/22]) (P = .017). The area under the curve survival values of PET/CT parameters were 0.777 for metabolic tumor volume (MTV), 0.500 for maximum standardized uptake value, 0.554 for peak standardized uptake value corrected for lean body mass, and 0.634 for total lesion glycolysis. A 50% cut-off value for the MTV reduction rate yielded the largest difference in survival between responders and nonresponders. On multivariate analysis, MTV reduction rates < 50% were independent predictors for relapse-free survival (hazard ratio [HR], 3.92; P = .044) and overall survival (HR, 14.08; P = .023). CONCLUSIONS: PERCIST was more accurate in determining NAT's therapeutic effects for PDAC than RECIST. MTV reduction rates were independent prognostic factors for PDAC.

O-Glycan-Altered Extracellular Vesicles: A Specific Serum Marker Elevated in Pancreatic Cancer.

Pancreatic cancer (PC) is among the most lethal malignancies due to an often delayed and difficult initial diagnosis. Therefore, the development of a novel, early stage, diagnostic PC marker in liquid biopsies is of great significance. In this study, we analyzed the differential glycomic profiling of extracellular vesicles (EVs) derived from serum (two cohorts including 117 PC patients and 98 normal controls) using lectin microarray. The glyco-candidates of PC-specific EVs were quantified using a high-sensitive exosome-counting system, ExoCounter. An absolute quantification system for altered glycan-containing EVs elevated in PC serum was established. EVs recognized by O-glycan-binding lectins ABA or ACA were identified as candidate markers by lectin microarray. Quantitative analyses using ExoCounter revealed that the ABA- or ACA-positive EVs were significantly increased in the culture of PC cell lines or in the serum of PC patients including carbohydrate antigen 19-9 negative patients with high area under curve values. The elevated numbers of EVs in PC serum returned to normal levels after pancreatectomy. Histological examination confirmed that the tumors stained with ABA/ACA. These specific EVs with O-glycans recognized by ABA/ACA are elevated in PC sera and can act as potential biomarkers in a liquid biopsy for PC patients screening.