Prediction of tumor-reactive T cell receptors from scRNA-seq data for personalized T cell therapy

The identification of patient-derived, tumor-reactive T cell receptors (TCRs) as a basis for personalized transgenic T cell therapies remains a time- and cost-intensive endeavor. Current approaches to identify tumor-reactive TCRs analyze tumor mutations to predict T cell activating (neo)antigens and use these to either enrich tumor infiltrating lymphocyte (TIL) cultures or validate individual TCRs for transgenic autologous therapies. Here we combined high-throughput TCR cloning and reactivity validation to train predicTCR, a machine learning classifier that identifies individual tumor-reactive TILs in an antigen-agnostic manner based on single-TIL RNA sequencing. PredicTCR identifies tumor-reactive TCRs in TILs from diverse cancers better than previous gene set enrichment-based approaches, increasing specificity and sensitivity (geometric mean) from 0.38 to 0.74. By predicting tumor-reactive TCRs in a matter of days, TCR clonotypes can be prioritized to accelerate the manufacture of personalized T cell therapies.

Bridging bytes and biopsies: A comparative analysis of ChatGPT and histopathologists in pathology diagnosis and collaborative potential

BACKGROUND AND AIMS

ChatGPT is a powerful artificial intelligence (AI) chatbot developed by the OpenAI research laboratory which is capable of analysing human input and generating human-like responses. Early research into the potential application of ChatGPT in healthcare has focused mainly on clinical and administrative functions. The diagnostic ability and utility of ChatGPT in histopathology is not well defined. We benchmarked the performance of ChatGPT against pathologists in diagnostic histopathology, and evaluated the collaborative potential between pathologists and ChatGPT to deliver more accurate diagnoses.

METHODS AND RESULTS

In Part 1 of the study, pathologists and ChatGPT were subjected to a series of questions encompassing common diagnostic conundrums in histopathology. For Part 2, pathologists reviewed a series of challenging virtual slides and provided their diagnoses before and after consultation with ChatGPT. We found that ChatGPT performed worse than pathologists in reaching the correct diagnosis. Consultation with ChatGPT provided limited help and information generated from ChatGPT is dependent on the prompts provided by the pathologists and is not always correct. Finally, we surveyed pathologists who rated the diagnostic accuracy of ChatGPT poorly, but found it useful as an advanced search engine.

CONCLUSIONS

The use of ChatGPT4 as a diagnostic tool in histopathology is limited by its inherent shortcomings. Judicious evaluation of the information and histopathology diagnosis generated from ChatGPT4 is essential and cannot replace the acuity and judgement of a pathologist. However, future advances in generative AI may expand its role in the field of histopathology.

Endothelial Indoleamine-2,3-Dioxygenase-1 is not Critically Involved in Regulating Antitumor Immunity in the Central Nervous System

The vascular niche of malignant gliomas is a key compartment that shapes the immunosuppressive brain tumor microenvironment (TME). The blood-brain-barrier (BBB) consisting of specialized endothelial cells (ECs) and perivascular cells forms a tight anatomical and functional barrier critically controlling transmigration and effector function of immune cells. During neuroinflammation and tumor progression, the metabolism of the essential amino acid tryptophan (Trp) to metabolites such as kynurenine has long been identified as an important metabolic pathway suppressing immune responses. Previous studies have demonstrated that indoleamine-2,3-dioxygenase-1 (IDO1), a key rate-limiting enzyme in tryptophan catabolism, is expressed within the TME of high-grade gliomas. Here, we investigate the role of endothelial IDO1 (eIDO1) expression for brain tumor immunity. Single-cell RNA sequencing data revealed that in human glioma tissue, IDO1 is predominantly expressed by activated ECs showing a JAK/STAT signaling pathway-related CXCL11⁺ gene expression signature. In a syngeneic experimental glioma model, eIDO1 is induced by low-dose tumor irradiation. However, cell type-specific ablation of eIDO1 in experimental gliomas did not alter frequency and phenotype of tumor-infiltrating T cells nor tumor growth. Taken together these data argue against a dominant role of eIDO1 for brain tumor immunity.

MEDB-72. MOLECULAR CHARACTERIZATION OF MEDULLOBLASTOMAS IN A SINGLE INSTITUTION

INTRODUCTION: The four molecular groups (WNT, SHH, Group 3 and Group 4) in medulloblastoma have been well established for the past decade. New subgroups within the four principal molecular groups have recently been discovered and recognized by WHO classification of Central Nervous System Tumours (5th edition). Subgroups were reported to have distinct somatic copy-number aberrations and clinical outcomes. This further classification could be helpful to refine prognostication and potentially provide risk stratification for treatment planning. AIM: To interrogate archival medulloblastoma samples using Oncoscan Microarray Assay, correlate with clinical features and consider the assay for clinical use. METHODS: Thirty-one archival samples with histological diagnosis of medulloblastoma and molecular grouping results from NanoString were retrieved and evaluated with Oncoscan Microarray Assay. Twenty-six were subjected to DNA methylation profiling to compare the results. Eight cases also had molecular data from next-generation sequencing (NGS) done with the in-house Ampliseq Childhood Cancer Panel. Correlation was made with clinical characteristics and outcomes of these 31 patients. RESULTS: OncoScan microarray showed distinct differences in the copy number profiles of the 31 medulloblastoma samples. Seventeen samples could be further classified into one of 12 subgroups. However, further subgrouping was challenging without first determining the main molecular group especially amongst non-WNT/SHH tumours. DNA methylation results provided corroboration with the Oncoscan subgrouping results in 25 of 26 samples. NGS panel detected additional genetic alterations in 5 of 8 samples. CONCLUSIONS: Oncoscan Microarray Assay showed potential in providing additional molecular information for further subgrouping of medulloblastoma, but was insufficient for determining the main molecular groups. Moving forward, molecular characterization could instead be done through use of NGS panel and DNA methylation, which provides tumour epigenetic profiling on top of copy number variants. These could be used alongside the NanoString platform, which is performed routinely for all medulloblastomas at our centre.

Explaining Osteomyelitis and Prosthetic Joint Infections (PJI) in terms of Biofilm - A Review

Osteomyelitis is a chronic infection of bones. Eradication of bone infection is usually with antibiotics and debridement, but it is slow and the infection can recur even after many years. It is now established that osteomyelitis is due to biofilm and a better understanding of the process is required. We review the development of biofilm and apply it to osteomyelitis management. The planktonic microbes' response to adverse conditions is the formation of biofilm. Bacterial infections in planktonic forms cause infections that can be controlled with antibiotics and immunisation, however the same microbe when its phenotype becomes biofilm is more resilient. The understanding of how planktonic bacteria convert to biofilm is one of the aims set out for this article.

Intracranial myxoid angiomatoid fibrous histiocytoma with "classic" histology and EWSR1:CREM fusion providing insight for reconciliation with intracranial myxoid mesenchymal tumors

Angiomatoid fibrous histiocytoma (AFH) is an uncommon soft tissue neoplasm that can exhibit diverse morphological features, including myxoid change. Rarely, the tumor occurs intracranially and poses considerable diagnostic challenges to neuropathologists. This is compounded by a recently coined entity, referred to as intracranial myxoid mesenchymal tumor (IMMT). These tumors show significant overlaps with intracranial myxoid AFH from clinicopathological and molecular genetic viewpoints. We described an unusual intracranial tumor in a 30-year-old man. The tumor exhibited "classic" histological features of myxoid AFH and EWSR1:CREM fusion, a relatively novel variant of EWSR1:CREB family fusion, first identified in IMMT. We also performed a comprehensive literature review comparing the clinicopathological features of intracranial AFHs and IMMTs. Peritumoral lymphoplasmacytic cuffing appears to be the only morphological finding that is consistently absent in reported cases of IMMT while being present in most intracranial AFHs. Otherwise, both tumors showed considerable overlaps in clinical, histological, and immunohistochemical features and have a common molecular genetic signature of EWSR1:CREB family fusion, including EWSR1:CREM fusion. Our case appeared to be the first described EWSR1:CREM-fused intracranial tumor to show prominent peritumoral lymphoplasmacytic cuffing and myxoid change in addition to most of the other "classic" morphologic features of AFH. As such, while the current literature appears to be lacking when it comes to defining intracranial myxoid AFH and IMMT as separate nosological entities, they likely represent a morphological spectrum of a common entity characterized by EWSR1 rearrangement, akin to solitary fibrous tumors and hemangiopericytomas with the signal transducer and activator of transcription 6 gene (STAT6) rearrangement.

Dermointegration in the exposed titanium cranioplasty: a possible protective phenomenon

Implant exposure is a known complication of titanium mesh cranioplasty and is usually managed by implant removal and/or exchange. We describe a case of exposed titanium mesh cranioplasty which was managed with implant exchange and bipedicled flap coverage, and showcase an interesting phenomenon of full-thickness skin present beneath the exposed mesh. This was confirmed on histopathology, which showed the presence of dermal appendages including pilosebaceous units and eccrine glands. We postulate that the mechanism behind this phenomenon involves islands of viable skin ‘dropping’ between holes in the mesh and coalescing beneath the exposed implant, as suggested by histopathology findings of nodular protrusions and varying degrees of epidermal hyperplasia. This protects the underlying dura from external infection. We propose for this phenomenon to be called dermointegration. Our findings suggest that similar cases, particularly patients who are not fit for general anaesthesia, may potentially be managed with a more conservative approach.

The Multifaceted Appearance of Supratentorial Ependymoma with ZFTA-MAML2 Fusion

Ependymomas are glial neoplasms with a wide morphological spectrum. The majority of supratentorial ependymomas are known to harbor ZFTA fusions, most commonly to RELA. We present an unusual case of a 9-year-old boy with a supratentorial ependymoma harboring a noncanonical ZFTA-MAML2 fusion. This case had unusual histomorphological features lacking typical findings of ependymoma and bearing resemblance to a primitive neoplasm with focal, previously undescribed myogenic differentiation. We discuss the diagnostic pitfalls in this case and briefly review the histological features of ependymoma with noncanonical gene fusions. Our report underscores the importance of molecular testing in such cases to arrive at the correct diagnosis. Supratentorial ependymomas with noncanonical fusions are rare, and more studies are necessary for better risk stratification and identification of potential treatment targets.

Frequency of discordance in programmed death-ligand 1 (PD-L1) expression between primary tumors and paired distant metastases in advanced cancers: a systematic review and meta-analysis

Background: To determine the frequency of discordance in programmed death-ligand 1(PD-L1) expression between primary tumors and paired distant metastases in advanced cancers.Methods: We searched MEDLINE and EMBASE for eligible studies and assessed their methodologic quality using QUADAS-2 tool. We estimated the discordant rates (positive to negative or vice versa) of PD-L1 expression in primary tumors and paired distant metastases using logistic-normal random effects model. We performed subgroup analyses based on the PD-L1 status of primary tumors (positive or negative), location of primary tumors (lung or others) and distant metastases (central nervous system or others), timing of distant metastases (synchronous or metachronous), positivity thresholds of PD-L1 expression (1% or 5%) and types of antibody clones used (E1L3N or SP142).Results: Thirteen eligible studies including 451 cases were identified. The included studies were judged to have low to unclear risk of bias. The pooled estimate of discordant rates in PD-L1 expression was 31% (95% CI= 19-47%), with high heterogeneity across the studies (I² = 75%). There was no significant effect modification in the discordant rates according to the predefined subgroups.Conclusion: Approximately one-third of advanced cancer cases have discordance in PD-L1 expression between primary tumors and paired distant metastases. A more liberal testing of PD-L1 expression in both primary and metastatic tumors is recommended in order to identify patients who may benefit from immune checkpoint blockade treatment. Further research exploring the mechanisms and its impact are warranted.

Vision loss in an immunocompetent child post varicella infection: A case report

Chickenpox may lead to several neurological complications. Optic neuritis is one of the complications which has rarely been described, especially in immunocompetent individuals. We report a case of an 11-year-old immunocompetent girl who presented with sudden onset bilateral vision loss three weeks after varicella eruption. Ophthalmic examination revealed bilateral optic disc edema. Diagnosis of bilateral optic neuritis secondary to varicella was established based upon the preceding medical history, supported with clinical and radiological findings.

Recurrent Extradural Myxopapillary Ependymoma With Oligometastatic Spread

Myxopapillary ependymomas are a slow-growing, grade I type glial tumor in the lumbosacral region. More rarely, they can present as extradural, subcutaneous sacrococcygeal, or perisacral masses, and it is under these circumstances that they are more likely to spread. Here, we report the presentation of a sacrococcygeal mass in patient that was initially resected confirming extradural myxopapillary ependymoma. At initial resection, multiple small pulmonary nodules were detected. This mass recurred 2 years later at the resection site with an interval increase in the previously imaged pulmonary nodules. Resection of both the post-sacral mass and largest lung metastasis confirmed recurrent myxopapillary ependymoma with oligometastatic spread. Because these tumors are rare, with extradural presentation being even more infrequent, to this date there are no definitive therapeutic guidelines for initial treatment and continued surveillance. For myxopapillary ependymoma, current standard of care is first-line maximal surgical resection with or without postoperative radiotherapy depending on the extent of disease and extent of resection. However, there remains insufficient evidence on the role of radiotherapy to oligometastatic foci in providing any further survival benefit or extending time to recurrence. Thus, prospective studies assessing the role of upfront treatment of oligometastases with local resection and adjuvant radiotherapy are needed for improved understanding of extradural myxopapillary ependymoma.

Anaplastic Oligodendroglioma with Transdural Extension

Oligodendrogliomas, the third most common primary gliomas, have a strict molecular definition, characterized by the combined presence of isocitrate dehydrogenase mutation and 1p19q codeletion. Herein, we describe an extremely unusual case of molecularly defined anaplastic oligodendroglioma with transdural extension into the frontal and ethmoid sinuses, without prior neurosurgical intervention or radiotherapy. The molecular profile of the tumor is also provided. To the best of our knowledge, this has never been reported before. Most of the previously reported glial tumors with transdural extension were cases of histologically proven glioblastomas and gliosarcomas, typically seen in the context of prior neurosurgical intervention and/or radiotherapy. This case adds to the limited literature on oligodendrogliomas with transdural extension. Further studies are necessary to elucidate the relationship between the incidence of transdural extension and molecular subtypes of oligodendrogliomas.

Discordance of epidermal growth factor receptor mutation between primary lung tumor and paired distant metastases in non-small cell lung cancer: A systematic review and meta-analysis

Purpose

To evaluate the rate of discordance of epidermal growth factor receptor (EGFR) mutation between primary lung tumor and paired distant metastases in non-small-cell lung cancer (NSCLC).

Methods

We performed a meta-analysis of 17 studies (518 cases) assessing discordance rates of EGFR mutation in primary tumors and paired distant metastases. We performed subgroup analyses based on EGFR mutation status in primary tumor (mutant or wildtype), site of distant metastasis (bone, central nervous system (CNS) or lung/ pleural), methods of testing (direct sequencing or allele-specific testing) and timing of metastasis (synchronous or metachronous).

Results

The overall discordance rate in EGFR mutation was low at 10.36% (95% CI = 4.23% to 18.79%) and varied widely between studies (I² = 83.18%). The EGFR discordance rate was statistically significantly higher in bone metastases (45.49%, 95% CI = 14.13 to 79.02) than CNS (17.26%, 95% CI = 7.64 to 29.74; P = 0.002) and lung/ pleural metastases (8.17%, 95% CI = 3.35 to 14.85; P < 0.001). Subgroup analyses did not demonstrate any significant effect modification on the discordance rates by the EGFR mutation status in primary lung tumor, methods of testing and timing of metastasis.

Conclusion

The overall discordance rate in EGFR mutation between primary lung tumor and paired distant metastases in NSCLC is low, although higher discordance rates were observed in bone metastases compared with CNS and lung/pleural metastases. Future studies assessing the impact of EGFR mutation discordance on treatment outcomes are required.

Frequency of discordance in programmed death ligand 1 (PD-L1) expression between primary tumors and paired distant metastases in advanced cancers: A systematic review and meta-analysis

e14290

Background: Randomized trials have demonstrated that PD-L1 expression in tumor cells predicts for response to PD-1 or PD-L1 checkpoint inhibitors in advanced cancers. However, the frequency of discordance in PD-L1 expression between primary tumors and paired distant metastases is currently unclear. We aimed to determine the discordance rate of PD-L1 expression between primary tumor and paired distant metastases in advanced cancers. Methods: We searched MEDLINE and EMBASE for eligible studies. We noted the discordance rate (positive-to-negative or vice versa) and performed subgroup analyses based on the PD-L1 expression in primary tumor, locations of primary tumor and distant metastases, positivity thresholds and type of antibody used for testing. We used QUADAS-2 tool to assess the methodologic quality of the included studies. We performed the meta-analysis using the logistic-normal random effects model. Results: We identified 11 eligible studies including 351 cases of lung, colorectal, breast and ovarian cancers. Nine studies were judged to have low risk of bias in their methodological quality. The overall discordance rate in PD-L1 expression between primary tumor and paired distant metastases was 28% (95% confidence interval (CI) = 18-41) with significant heterogeneity among the studies (chi-square test P-value < 0.0001). There was no statistically significant differences in discordance rates between the subgroups: PD-L1-positive (40%, 95% CI = 21-63) vs PD-L1-negative primary tumors (21%, 95% CI = 12-34), lung primary (31%, 95% CI = 14-55) vs colorectal/ breast/ ovarian primary (27%, 95% CI = 19-37), central nervous system metastases (22%, 95% CI = 8-47) vs liver/ lung/ pleural/ peritoneum metastases (34%, 95% CI = 24-46); 1% (23%, 95% CI 16-33) vs 5% positivity threshold (33%, 95% CI 11-68); E1L3N (42%, 95% CI 10-82) vs SP142 antibody (27%, 95% CI 20-36). Conclusions: The discordance in PD-L1 expression between primary tumors and paired distant metastases is close to 30%, which could potentially affect response to immunotherapy. Further works exploring the mechanisms and impact of this discordance are warranted.

miR-375 inhibits the proliferation and invasion of glioblastoma by regulating Wnt5a

The aberrant expression of microRNA-375 (miR-375) has been proved to be associated with carcinogenesis. However, the role of miR-375 in glioblastoma (GBM) remains unknown. The aim of this study was to investigate biological functions and its molecular mechanisms of miR-375 in GBM cells. In this study, real-time PCR results showed that the level of miR-375 expression in GBM tissues and GBM cell lines (U87 and U251) was decreased. Using MTT assay, Transwell migration and invasion assay, we demonstrated that miR-375 overexpression significantly suppress cell proliferation, cell migration and cell invasion capacity in U87 and U251 cells. However, downregulation of miR-375 had reverse effects on cell proliferation, migration and invasion. Targeting association analysis, dual luciferase assay, RT-PCR and western blot analysis results confirmed that miR-375 could target the 3'UTR of Wnt5a mRNA and regulated its protein expression. Further studies also find overexpression of Wnt5a could significantly reverse miR-375-mediated proliferation, migration and invasion on U87 and U251 cells. Therefore, we concluded that miR-375 inhibited the proliferation and invasion of GBM by regulating Wnt5a and might be a possible therapeutic agent for GBM.

Two Extraordinary Sellar Neuronal Tumors: Literature Review and Comparison of Clinicopathologic Features

Objectives

The list of tumors involving the pituitary gland has been expanded to include a variety of neuronal and paraneuronal tumors in the 2017 World Health Organization tumor classification of endocrine organs. All the entities included in this category are distinctly rare, with limited case reports in the literature.

Methods

We illustrate two extraordinary sellar tumors with neuronal differentiation: a sellar paraganglioma and a sellar neurocytoma, with thorough literature review and comparison of the clinicopathologic features of these entities.

Results

Both entities are exceptionally rare and tend to be misdiagnosed as pituitary adenoma preoperatively. Both entities demonstrate frequent clinical recurrence compared with pituitary adenoma, as well as the rare occurrence of metastatic disease.

Conclusions

In evaluating a sellar tumor with an uncommon morphology and neuroendocrine differentiation, an increased awareness of the unusual entities that may involve the sellar region and a judicious panel of immunohistochemical studies should improve the diagnosis.

Diagnosis and Management of Radiation Necrosis in Patients With Brain Metastases

The use of radiotherapy, either in the form of stereotactic radiosurgery (SRS) or whole-brain radiotherapy (WBRT), remains the cornerstone for the treatment of brain metastases (BM). As the survival of patients with BM is being prolonged, due to improved systemic therapy (i.e., for better extra-cranial control) and increased use of SRS (i.e., for improved intra-cranial control), patients are clinically manifesting late effects of radiotherapy. One of these late effects is radiation necrosis (RN). Unfortunately, symptomatic RN is notoriously hard to diagnose and manage. The features of RN overlap considerably with tumor recurrence, and misdiagnosing RN as tumor recurrence may lead to deleterious treatment which may cause detrimental effects to the patient. In this review, we will explore the pathophysiology of RN, risk factors for its development, and the strategies to evaluate and manage RN.

Primary Nasopharyngeal Kaposi Sarcoma as Index Diagnosis of AIDS in a Previously Healthy Man

A 38-year-old, previously healthy man presented with blood-stained saliva and epistaxis. A 3 mm nasopharyngeal lesion was found. A biopsy was performed and microscopic examination revealed a Kaposi sarcoma. The patient was subsequently found to be positive for human immunodeficiency virus (HIV). The diagnosis of Kaposi sarcoma in the presence of HIV infection advanced his disease to Acquired Immunodeficiency Syndrome (AIDS). Primary manifestation of Kaposi sarcoma in the nasopharynx is extremely rare. The histologic differential diagnosis of Kaposi sarcoma in this unusual site, especially without the clinical history of immunosuppression, is broad. Awareness that nasopharynx can be a primary involvement site of Kaposi sarcoma and serves as index diagnosis of AIDS is important given its serious clinical implication.

Developing neurites from mouse basal forebrain gonadotropin-releasing hormone neurons use Sonic hedgehog to modulate their growth

Hypothalamic gonadotropin-releasing hormone (GnRH) neurons are required for fertility in all mammalian species studied to date. GnRH neuron cell bodies reside in the basal forebrain, and most extend long neurites in the caudal direction to terminate at the median eminence (ME), the site of hormone secretion. Using in vitro neurite growth assays, histological methods, and genetic deletion strategies in mice we have analysed the role of the morphogen and neurite growth and guidance molecule, Sonic hedgehog (Shh), in the growth of GnRH neurites to their target. Immunohistochemistry revealed that Shh was present in the basal forebrain, the preoptic area (POA) and mediobasal hypothalamus (MBH) at gestational day 14.5 (GD 14.5), a time when GnRH neurites grow towards the ME. Furthermore, in situ hybridization revealed that mRNA encoding the Shh receptor, Smoothened (Smo), was present in GnRH neurons from GD 15.5, when the first GnRH neurites are extending towards the MBH. In vitro neurite growth assays using hypothalamic explants from GD 15.5 fetuses in 3-D collagen gels showed that Shh was able to significantly stimulate GnRH neurite outgrowth. Finally, genetic deletion of Smo specifically from GnRH neurons in vivo, using Cre-loxP technology, resulted in a significant decrease in GnRH neurites innervating the ME. These experiments demonstrate that GnRH neurites use Shh for their neurite development, provide further understanding of the mechanisms by which GnRH nerve terminals arrive at their site of hormone secretion, and identify an additional hypothalamic neuronal population for which Shh/Smo signaling is developmentally important.

Report of a Novel Case of Anaplastic Olfactory Groove Meningioma and Its Methylation Subtype

We report a novel case of a World Health Organization grade 3 anaplastic meningioma arising from the olfactory groove in an 83-year-old woman. Molecular and methylation profiling confirm this lesion to be an NF2 subtype, methylation class intermediate type B meningioma. As most meningiomas in this location are indolent SMO subtype lesions, our report suggests that even though rare, aggressive NF2 subtype meningiomas can also occur along the midline anterior skull base.

Rapidly Fatal Radiation-induced Glioblastoma

Glioblastoma (GBM) typically occurs as a primary tumour (i.e., primary GBM) and predominantly affects elderly patients. The remaining ~10% occur as a result of malignant progression from lower grade astrocytic tumours (i.e., secondary GBM). Although there are no certain causative environmental agents, prior radiation exposure may play a role. We report on a patient who had been treated six years prior for a vestibular schwannoma with high-dose conventional radiotherapy and subsequently developed a rapidly fatal glioblastoma at the same location. The diagnosis was confirmed by routine histopathology as well as more advanced techniques, such as whole genome copy number analysis. 

[Surgical options for chronic pancreatitis]

Objective: Discuss the surgical options for the chronic pancreatitis on the basis of anatomical morphological changes. Methods: A retrospective review of chronic pancreatitis patients in Department of Pancreatic Surgery, West China Hospital, Sichuan University between January 2010 and December 2014 was performed. The data of medical records, image feature, surgical types and records of follow-up were collected. Total 295 patients including 275 male and 20 female aged from 14 to 74 years with median age of 51 years. The clinical symptoms included abdominal pain in 280 cases, jaundice in 3 cases, single hemorrhage in digestive tract, diarrhea or mellitus in 12 cases. The anatomical morphological changes included pancreatic fibrosis and atrophy of the main pancreatic duct lesions in 44 cases (14.9%), inflammatory mass in the pancreatic head in 69 cases (22.4%), sporadic stones with calcification in the pancreatic head in 165 cases(55.9%), hyperplasia mass of pancreatic head and body in 14 cases (4.8%), sporadic stones with calcification in whole branch ducts accompanied with different degree of hyperplasia in whole pancreas in 3 cases (1.0%). The surgical options included longitudinal pancreaticojejunostomy, duodenum-preserving pancreatic head resection, Frey/Frey+ distal pancreatectomy, total and subtotal pancreatectomy. All patients were followed-up for 3 to 6 months in the outpatient. A cross-sectional study was carried out by telephone, letters, questionnaire and outpatient from April to June 2016. Results: Among 295 patients, 267 cases were followed-up for an average time of 40 months(18 to 78 months), 28 cases were lost to followed-up(9.5%). Pain remission rate of pancreatic fibrosis and atrophy of the main pancreatic duct lesions patients was 97.0%, of inflammatory mass in the pancreatic head patients was 96.8%, of sporadic stones with calcification in the pancreatic head patients was 96.6%, of hyperplasia mass of pancreatic head and body patients was 12/13, of sporadic stones with calcification in whole branch ducts accompanied with different degree of hyperplasia in whole pancreas patients was 3/3. There were 19 cases(9.6%) with blood glucose rising. Conclusion: According to the pathological changes of chronic pancreatitis, the reasonable choice of surgical procedures can be done to maximize the removal of the cause of pain and the preservation of pancreatic tissue.

[Viability of extended distal pancreatectomy for pancreatic adenocarcinoma of the body or tail]

OBJECTIVE

To analyze the viability of extended distal pancreatectomy and the associated prognostic factors.

METHODS

The data of 57 patients with pancreatic adenocarcinoma who underwent standard distal pancreatectomy(DP) or extended distal pancreatectomy(EDP) from January 2011 to December 2014 were reviewed retrospectively. Thirty-five patients were performed with DP and 22 with EDP. Operation safety and survival benefit between DP and EDP were compared by t-test or χ(2) test.Cox regression analysis was used to explore the prognostic indicators.

RESULTS

Compared to DP group, operation time((255±91)min vs.(208±80)min)(t=2.066, P=0.044) and ratio of blood transfusion (50.0% vs.17.1%)(χ(2)=12.836, P=0.008) were greater in EDP group, respectively.There were no significant differences in amount of intraoperative blood loss and postoperative duration of hospitalization. Delayed gastric emptying was greater in EDP(22.7% vs.2.9%)(Z=-2.251, P=0.027), while other complications had no differences. Mortality and ratio of relaparotomy also showed no differences. Median survival following DP was 13.1 months compared to 8.2 months following EDP. There was no difference in survival between DP and EDP. According to the results of multivariate analysis, tumor size(RR=1.275, P=0.03)and perioperative blood transfusions(RR=2.673, P=0.04) were independent prognostic factors.

CONCLUSIONS

Though patients with pancreatic adenocarcinoma who undergo EDP have a worse pathologic staging, they will gain a comparable long-term survival to the patients undergo DP. Tumor size and perioperative blood transfusions are independent prognostic factors.

A Torted Ruptured Intra-abdominal Testicular Seminoma Presenting As An Acute Abdomen

The susceptibility of the undescended testis to malignant transformation is well documented. The most common location of the undescended testis is within the inguinal canal, with only a minority located within the abdominal cavity. When a testicular mass develops, the risk of torsion increases. We describe a large intra-abdominal testicular seminoma that had undergone torsion, rupture and haemorrhage, presenting as an acute abdomen. A 30 year old man presented to the emergency department with right iliac fossa pain. Computed tomography in the emergency department showed haemoperitoneum and a torted large left testicular mass, likely malignant. The patient underwent laparotomy and excision of the mass. Histologic examination revealed a grossly enlarged seminomatous testis which had torted and ruptured. While pre-operative imaging diagnosis of an intra-abdominal testicular seminoma has been published, reports are few. To the best of the author's knowledge pre-operative imaging diagnosis of a malignant testicular mass with torsion and intra-abdominal haemorrhage presenting as an acute abdomen has not been described before.

Meta-analysis of pancreaticogastrostomy versus pancreaticojejunostomy after pancreaticoduodenectomy

BACKGROUND

Surgical reconstruction following pancreaticoduodenectomy (PD) is associated with significant morbidity and mortality. Because of great variability in definitions of specific complications, it remains unclear whether there is a difference in complication rates following the two commonest types of reconstruction, pancreaticogastrostomy (PG) and pancreaticojejunostomy (PJ). Published consensus definitions for postoperative pancreatic fistula (POPF) have led to a series of randomized clinical trials (RCTs) uniquely placed to address this question.

METHODS

A literature search was carried out to identify all RCTs comparing postoperative complications of PG versus PJ reconstruction following PD published between January 1995 and December 2013. Pooled odds ratios (ORs) with 95 percent confidence intervals (c.i.) were calculated using fixed-effect or random-effects models.

RESULTS

In total, seven RCTs with 1121 patients were included. Four of these trials applied definitions as published by the International Study Group on Pancreatic Fistula (ISGPF). Using ISGPF definitions, the incidence of POPF was lower in patients undergoing PG than in those having PJ (OR 0·50, 95 per cent c.i. 0·34 to 0·73; P < 0·001). Using definitions applied by each individual study, PG was associated with significantly lower rates of POPF (OR 0·51, 0·36 to 0·71; P < 0·001), intra-abdominal fluid collection (OR 0·50, 0·34 to 0·74; P < 0·001) and biliary fistula (OR 0·42, 0·18 to 0·93; P = 0·03) than PJ.

CONCLUSION

Meta-analysis of four RCTs based on ISGPF criteria, and seven RCTs using non-standard criteria, revealed that PG reduced the incidence of POPF after PD compared with PJ.

Muco-submucosal elongated polyps of the gastrointestinal tract: A case series and a review of the literature

We present three cases of gastrointestinal muco-submucosal elongated polyps, two located in the duodenum and one in the descending colon. All three cases had a characteristic, “worm-like” endoscopic appearance and were lined by unremarkable mucosa. The vascular component was located in the submucosa and was composed of a mixture of variably dilated blood vessels (capillaries and veins) and lymphatics. The duodenal polyps displayed lipomatous metaplasia of the submucosal stroma. The dual vascular phenotype of the vascular component was confirmed by immunohistochemistry with D2-40 and CD31.

Pneumocystis carinii (jirovecii) pneumonia (PCP): the most common opportunistic infection observed in HIV/AIDS cases at the University Malaya Medical Centre, Kuala Lumpur, Malaysia

This retrospective study was conducted among 59 HIV/AIDS patients with opportunistic infections admitted to the University Malaya Medical Centre between 2000 and 2009. Fifty-five point nine percent of cases were Chinese, 25.4% were Malays, 11.9% were Indians and 6.8% were of unknown ethnic origin. The male:female ratio was 2.9:1 (44 males and 15 females). The highest prevalence (38.9%) occurred in the 30-39 year old age group. Men comprised 47.7% and women 53.3%; the majority of both were married. The majority of cases were Malaysians (89.8%) and the rest (10.2%) were immigrants. Most of the patients (18.6%) were non-laborers, followed by laborers (11.9%), the unemployed (5.1%) and housewives (3.4%). The most common risk factor was unprotected sexual activity (20.3%). The two most common HIV/AIDS related opportunistic infections were Pneumocystis carinii (jirovecii) pneumonia (PCP) (62.7%) and toxoplasmosis (28.8%). Seventy-two point nine percent of patients had a CD4 count <200 cells/microl and 5.1% had a CD4 count >500 cells/microl. Eleven point nine percent of cases died during study period. A low CD4 count had a greater association with opportunistic infections. Most of the patients presented with fever (44.1%), cough (42.4%) and shortness of breath (28.8%). Detection of the etiologic pathogens aids clinicians in choosing appropriate management strategies.

Methylator phenotype of malignant germ cell tumours in children identifies strong candidates for chemotherapy resistance

BACKGROUND

Yolk sac tumours (YSTs) and germinomas are the two major pure histological subtypes of germ cell tumours. To date, the role of DNA methylation in the aetiology of this class of tumour has only been analysed in adult testicular forms and with respect to only a few genes.

METHODS

A bank of paediatric tumours was analysed for global methylation of LINE-1 repeat elements and global methylation of regulatory elements using GoldenGate methylation arrays.

RESULTS

Both germinomas and YSTs exhibited significant global hypomethylation of LINE-1 elements. However, in germinomas, methylation of gene regulatory regions differed little from control samples, whereas YSTs exhibited increased methylation at a large proportion of the loci tested, showing a 'methylator' phenotype, including silencing of genes associated with Caspase-8-dependent apoptosis. Furthermore, we found that the methylator phenotype of YSTs was coincident with higher levels of expression of the DNA methyltransferase, DNA (cytosine-5)-methyltransferase 3B, suggesting a mechanism underlying the phenotype.

CONCLUSION

Epigenetic silencing of a large number of potential tumour suppressor genes in YSTs might explain why they exhibit a more aggressive natural history than germinomas and silencing of genes associated with Caspase-8-dependent cell death might explain the relative resistance of YSTs to conventional therapy.

A case of coexisting Warthin tumor and langerhans cell histiocytosis associated with necrosis, eosinophilic abscesses and a granulomatous reaction in intraparotid lymph nodes

We present a patient (50-year-old male) with coexisting Warthin tumor and involvement of two intraparotid lymph nodes by Langerhans cell histiocytosis associated with necrosis, eosinophilic abscesses and a granulomatous reaction. This is the second documented case of this unusual combination of histological changes in nodal Langerhans cell histiocytosis and the first case involving intraparotid lymph nodes occurring together with an ipsilateral Warthin tumor.

Nutritional supplement use among university athletes in Singapore

INTRODUCTION

Nutritional supplements used by athletes can be classified as sports food, dietary supplements and ergogenic aids. The aim of this study was to examine the use of such supplements among university athletes in Singapore.

METHODS

82 athletes from 16 sport disciplines completed a questionnaire which sought information on demographical parameters, type of supplements, frequency of use, motivations, knowledge, expenditure and side effects.

RESULTS

The prevalence of supplement use was 76.8 percent and 20 different products were used. Each individual consumed a mean and standard deviation of 3.18 +/- 1.7 products over a 12-month period. The mean number of products consumed daily was 2.1 +/- 1.2. Popular products included sports drinks, vitamin C, multivitamins and traditional/herbal preparations such as essence of chicken, bird's nest and ginseng. Before using a product, 65.9 percent sought information, usually from the media, the Internet, coaches and fellow athletes. However, many did not know where to obtain reliable information and 86.4 percent were also unaware that supplementation can have adverse effects.

CONCLUSION

Although there is a high prevalence of supplement use in our study population, many do not have accurate information about these products. Hence, there is an urgent need to provide athletes with education and access to scientific and unbiased information.

Paediatric extracranial germ cell tumours: a retrospective review

INTRODUCTION

Germ cell tumours (GCTs) are rare, constituting 3% of all childhood malignancies. The aim of this study was to analyse the epidemiology and outcome of these patients.

MATERIALS AND METHODS

A retrospective, cohort study was conducted on 38 paediatric patients presenting with extracranial GCTs, treated at the Singapore General Hospital, Tan Tock Seng Hospital and Kandang Kerbau Women's and Children's Hospital from 1 January 1989 to 30 June 1999. The median age at diagnosis was 1.7 years (0 to 13 years).

RESULTS

There was no sex or racial preponderance. Eighteen patients (47.3%) had teratomas, 16 (42.1%) had yolk sac tumours, 1 (2.6%) had dysgerminoma and 3 (7.9%) had mixed GCTs. Thirty-four patients (89.5%) had Stage I disease, 1 (2.6%) had Stage II disease, 1 (2.6%) had Stage III disease and 2 (5.3%) had metastatic disease. Complete tumour resection was achieved in 36 of the 38 patients (95%). Cisplatin-based combination chemotherapy was given to 11 patients (28.9%). None of the patients received radiotherapy. Complications from chemotherapy included anaemia requiring packed red cell transfusion (n = 3), Port-a-cath sepsis requiring removal (n = 1), febrile neutropenia (n = 1) and nephropathy (n = 1).

CONCLUSION

Using the Kaplan-Meier life tables, the overall and event-free survivals at 10 years for the patients with malignant GCTs were 96% and 88%, respectively, with a mean follow-up period of 5.1 years (0.7 to 10 years). The majority of the patients presented with early Stage I disease and this contributed to our high survival rate.

Electronic detection of single-base mismatches in DNA with ferrocene-modified probes

Genotyping and gene-expression monitoring is critical to the study of the association between genetics and drug response (pharmacogenomics) and the association of sequence variation with heritable phenotypes. Recently, we developed an entirely electronic method for the detection of DNA hybridization events by the site-specific incorporation of ferrocenyl derivatives into DNA oligonucleotides. To perform rapid and accurate point mutation detection employing this methodology, two types of metal-containing signaling probes with varying redox potentials are required. In this report we describe a new ferrocene-containing phosphoramidite 9 that provides a range of detectable redox potentials. Using automated DNA/RNA synthesis techniques the two ferrocenyl complexes were inserted at various positions along oligonucleotide probes. Thermal stability analysis of these metal-containing DNA oligonucleotides indicates that incorporation of 9 resulted in no destabilization of the duplex. A mixture of oligonucleotides containing compounds 9 and I was analyzed by alternating current voltammetry (ACV) monitored at the 1st harmonic. The data demonstrate that the two ferrocenyl oligonucleotide derivatives can be distinguished electrochemically. A CMS-DNA array was prepared on an array of gold electrodes on a printed circuit board substrate with a self-assembled mixed monolayer, coupled to an electronic detection system. Experiments for the detection of a single-base match utilizing two signaling probes were carried out. The results demonstrate that rapid and accurate detection of a single-base mismatch can be achieved by using these dual-signaling probes on CMS-DNA chips.

[Detection of brain vascular diseases with CT angiography]

OBJECTIVE

To identify the diagnostic effect of spiral CT in brain vascular diseases.

METHODS

Sixty four patients underwent CT angiography, including 22 patients with subarachnoid hemorrhage (SAH), 6 patients with oculomotor nerve paralysis, 5 patients with brain substance hemorrhage, 6 patients with arteriovenous malformation (AVM), 4 patients with mass or aneurysm, 5 patients with brain infarction, 16 patients with epilepsy or headache and dizzy. 8 cases also underwent digital subtraction angiography (DSA), 4 cases were performed operation in 64 cases.

RESULTS

Spiral computed tomography angiography (SCTA) was all succeeded in 64 cases. 26 aneurysms and 8 AVMs were found by SCTA; in 6 of 8 cases of AVMs, their supply arteries and drainage veins were clearly displayed; SCTAs of 5 cases with substance hemorrhage were normal; in 1 of 5 cases with cerebral hemisphere infarction, its internal carotid obstruction was demonstrated by SCTA; the results of 12 SCTAs were identical with the results of their DSA or operation.

CONCLUSION

SCTA is a useful non-invasive inspection method for detecting brain vascular diseases such as aneurysms and AVMs.

Transcription of the interferon gamma (IFN-gamma )-inducible chemokine Mig in IFN-gamma-deficient mice

MuMig or Mig (murine monokine induced by interferon gamma) is a CXC chemokine whose induction is thought to be strictly dependent on interferon gamma (IFN-gamma). Here we have studied the expression of this chemokine gene in various organs of mice infected with vaccinia virus. We have employed animals deficient in either IFN-gamma (IFN-gamma(-/-)), or receptors for IFN-alpha/beta, IFN-gamma, or both IFN-alpha/beta and IFN-gamma (DR(-/-)) to dissect out the role of interferons in the induction of Mig during the host response to virus infection. Our data show that Mig mRNA and protein are expressed in organs of vaccinia virus-infected IFN-gamma(-/-) mice, albeit at lower levels compared with infected, wild-type animals. In the DR(-/-) mice and in IFN-gamma(-/-) mice treated with a neutralizing antibody to IFN-alpha/beta, Mig mRNA transcripts were completely absent. Our data indicate that, in vaccinia virus-infected IFN-gamma(-/-) mice, Mig mRNA expression is mediated through the interaction between IFN-gamma responsive element 1 (gammaRE-1) and IFN-alpha/beta-induced STAT-1 complex referred to as IFN-gamma response factor 2 (gammaRF-2). Further, our findings support the view that gammaRF-2 is the IFN-alpha/beta induced STAT-1 complex, IFN-alpha-activated factor. We have found that, in the absence of IFN-gamma, IFN-alpha/beta are able to induce Mig in response to a viral infection in vivo.

Squalamine analogues as potential anti-trypanosomal and anti-leishmanial compounds

This paper concerns the synthesis of various simplified analogues of the novel anti-microbial agent, squalamine. The compounds were then investigated for activity against Trypanosoma brucei, the causative agent of African trypanosomiasis, Trypanosoma cruzi, the causative agent of Chagas disease and Leishmania donovani, the causative agent of visceral leishmaniasis. Several compounds showed in vitro activity, especially against T. brucei and L. donovani. However, one compound showed poor in vivo activity.

The incidence of IDDM in Singapore children

OBJECTIVE

To determine the incidence of insulin dependent diabetes mellitus (IDDM) in children 0-12 years of age in Singapore, which has a population of 2.9 million.

METHODS

The primary source was a 2-year phone and mail survey of doctors in the government and government restructured hospitals and the private sector. The secondary source was the membership records of the Diabetes Society of Singapore.

RESULTS

Using the capture-recapture method, ascertainment was assessed to be 92.2% complete. The age standardised incidence rate was 2.46 per 100,000 children 0-12 years old, for the period 1992-1994 (95% confidence interval: 2.16-2.75). The data seemed to indicate a rising incidence of IDDM in this population, being 1.4/100,000 in 1992, 2.4/100,000 in 1993 and 3.8/100,000 in 1994. The male: female ratio is 1:1.85. There was seasonal variation with fewer cases from July to October and more from November to May. Five percent of patients had a first degree relative with IDDM. Malays appeared to have a lower incidence (1.23/100,000) compared to the Chinese (2.25/100,000) and the Indians (5.78/100,000).

CONCLUSIONS

The incidence of IDDM in Singapore children is similar to that reported for Hong Kong and Japan, but higher than that for Shanghai. The female preponderance is similar to that seen in other Asian population. The data suggests a rising incidence of IDDM in Singapore and differences in incidence between the Malays, Chinese and Indians, but further observations are needed.

Ecthyma gangrenosum in a patient with hypogammaglobulinemia

Ecthyma gangrenosum is a characteristic skin lesion that is caused by Pseudomonas aeruginosa (P. aeruginosa) in the majority of cases. Systemic P. aeruginosa usually complicates debilitating conditions like leukaemia, burns and cystic fibrosis. We report a patient with underlying hypogammaglobulinemia who developed ecthyma gangrenosum secondary to P. aeruginosa septicaemia, which was potentially life-threatening. Recognition of the characteristic skin lesions with prompt initiation of appropriate antibiotics and intravenous immunoglobulins were life-saving. A review of the English literature reports three other cases of ecthyma gangrenosum in patients with underlying hypogammaglobulinemia.