Verifying a novel bile cytology scoring system

BACKGROUND

The scoring system for bile cytology (SSBC) aims to improve bile cytology diagnostic accuracy. Here, the practicality of SSBC was verified by multiple cytotechnologists.

METHODS

Bile cytological specimens were evaluated by 24 cytotechnologists using SSBC. The samples were assessed before using the SSBC (first-time assessment) according to three categories: benign, indeterminate, and malignant. A first scoring evaluation (FSE) was then performed using SSBC; each item in the scoring system was classified as present or absent. After distributing an instruction sheet with diagnostic criteria, a second scoring evaluation (SSE) was performed using SSBC. Each method was evaluated using diagnostic accuracy and interobserver and intraobserver agreement.

RESULTS

Several samples were assessed as indeterminate in the first-time assessment. Although the specificity of the SSE improved, the sensitivity and accuracy decreased compared with those of the FSE. The overall interobserver agreement was fair for all parameters, including abnormal chromatin, irregular internuclear distances, irregularly overlapped nuclei, irregular cluster margins, and final evaluation in the FSE and SSE. The final evaluation by histological type exhibited slight agreement for well-differentiated tubular adenocarcinoma and almost perfect agreement for poorly differentiated tubular adenocarcinoma in the FSE and SSE. For moderately differentiated tubular adenocarcinoma, agreement was moderate in the FSE and fair in the SSE. For cholangitis, a slight agreement was observed in the FSE, which improved to fair in the SSE.

CONCLUSIONS

Although the SSBC is expected to improve specificity, there exists ambiguity regarding SSBC criteria and interindividual assessment differences. Therefore, the objective assessment method should be revised.

Hepatocellular carcinoma in a transplanted donor liver and colon cancer developing in a patient with a complex background: A case report

The development of tumors in livers transplanted from hepatitis B virus (HBV)-negative donors to patients with hepatitis B and cirrhosis is rare. The present study describes the case of a woman in her 60s who developed hepatocellular carcinoma (HCC) in her grafted liver, 19 years after transplantation, as well as a metachronous colorectal tumor. The pathological findings, including clinical, immunohistochemical and molecular results, are described in the present case report. The liver tumor was a conventional HCC and the colorectal tumor comprised a tubular adenocarcinoma. Immunohistochemistry of both tumors showed a loss of expression of mutL homolog 1 and postmeiotic segregation increased 2 in the tumor cells, confirming microsatellite instability-high (MSI-H) status. Furthermore, a molecular study detected the presence of genes located on the Y chromosome in the normal and tumor tissues of the liver, proving that the HCC occurred in the grafted liver. The present report also discusses that prolonged use of immunosuppressive drugs to prevent post-transplant rejection, poorly controlled diabetes mellitus and MSI-H may have contributed to the risk of tumor development.

A case of extranodal NK/T-cell lymphoma, nasal type, diagnosed by scraping cytology of the maxillary gingiva

Extranodal NK/T-cell lymphoma (ENKTL), nasal type, is often seen in the head and neck region, but there have been rare instances of this disease with initial presentation as a lesion in the oral mucosa. The patient, a woman in her seventh decade of life, presented with an ulcer in the maxillary gingiva, and scraping cytology and biopsy were performed. Cytological specimens showed solitary or small aggregating cells with marked atypia in a necrotic background. Tumor cells were detected that had various nuclear shapes and azure granules in the cytoplasm. Biopsy showed that the tumor cells had diffusely infiltrated or interdigitated into the subepithelium. Immunohistochemistry revealed that the tumor cells had T- and NK cell phenotypes and were Epstein-Barr virus-encoded small RNA (EBER) positive, leading to a diagnosis of ENKTL. Thus, when nonepithelial tumor cells in a necrotic background and prominent atypia are found, as in this case, it is important to carefully observe for azurophil granules in the cytoplasm for differential diagnosis considerations.

Nicolaioidesin C: An Antiausterity Agent Shows Promising Antitumor Activity in a Pancreatic Cancer Xenograft Mouse Model

Human pancreatic tumors are hypovascular in nature, and their tumor microenvironment is often characterized by hypoxia and severe nutrient deprivation due to uncontrolled heterogeneous growth, a phenomenon known as "austerity". However, pancreatic tumor cells have the inherent ability to adapt and thrive even in such low nutrient and hypoxic microenvironments. Anticancer drugs such as gemcitabine and paclitaxel, which target rapidly proliferating cells, are often ineffective against nutrient-deprived pancreatic cancer cells. In order to overcome this limitation, the search for novel agents that can eliminate cancer cells' adaptations to nutrition starvation, also known as "antiausterity" agents, represents a promising strategy to make the cancer cells susceptible to treatment. The natural product (+)-nicolaioidesin C (Nic-C) was found to have potent antiausterity activity against the PANC-1 human pancreatic cancer cell line in a nutrient-deprived condition. However, its efficacy in vivo remained untested. To address this, we synthesized Nic-C in its racemic form and evaluated its antitumor potential in a human pancreatic cancer xenograft model. Nic-C inhibited pancreatic cancer cell migration and colony formation and significantly inhibited tumor growth in MIA PaCa-2 xenografts in a dose-dependent manner. Furthermore, Nic-C inhibited the Akt/mTOR and autophagy signaling pathways in both in vitro and in vivo studies. Metabolomic profiling of in vivo tumor samples suggests that Nic-C downregulates amino acid metabolism while upregulating sphingolipid metabolism.

Endoscopic ultrasound-guided fine-needle biopsy of solid pancreatic tumors with 3 versus 12 to-and-fro movements: A multicenter prospective randomized controlled study

BACKGROUND AND AIMS

A novel endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) needle enabled physicians to obtain sufficient pathological samples with fewer to-and-fro movements within the lesion. We compared the diagnostic yields of EUS-FNB with 3- and 12-to-and-fro movements (3-TAFs and 12-TAFs) at each puncture pass.

METHODS

The primary endpoint of this multicenter, non-inferiority, crossover, randomized controlled trial involving six centers was diagnostic sensitivity. Secondary endpoints included diagnostic accuracy and quantity and quality evaluation of EUS-FNB samples. Length of the macroscopically visible core (MVC) and microscopic histological quantity were used for quantitative evaluation. Macroscopic visual and microscopic histological evaluations were performed for qualitative evaluation.

RESULTS

Among 110 patients (220 punctures, 110 for 3-TAFs and 12-TAFs each), 105 (210 punctures) had malignant histology. Diagnostic sensitivity for malignancy of 3-TAFs (88.6%) was not inferior to that of 12-TAFs (89.5%) (difference: -0.9%; 95% confidence interval: -9.81-7.86). Diagnostic accuracy for malignancy was 92.7% and 94.6% for 3-TAFs and 12-TAFs, respectively. Overall median MVC length was 13.5 mm in both groups. The 3-TAFs group had a significantly higher rate of score ≥3 on macroscopic visual quality evaluation than the 12-TAFs group (71.8% vs. 52.7%, p=0.009). No significant inter-group differences existed in microscopic histological quantity and quality evaluations (quantity evaluation: 3-TAFs 88.2% vs. 12-TAFs 83.6%; quality evaluation: 3-TAFs 90.0% vs. 12-TAFs 89.1%).

CONCLUSIONS

Diagnostic sensitivity and accuracy of EUS-FNB with 3-TAFs were not inferior to those with 12-TAFs for solid pancreatic lesions. The 3-TAFs group showed significantly less blood contamination in sampled tissues than the 12-TAFs group.

Depletion of CD206+ M2-like macrophages induces fibro-adipogenic progenitors activation and muscle regeneration

Muscle regeneration requires the coordination of muscle stem cells, mesenchymal fibro-adipogenic progenitors (FAPs), and macrophages. How macrophages regulate the paracrine secretion of FAPs during the recovery process remains elusive. Herein, we systemically investigated the communication between CD206⁺ M2-like macrophages and FAPs during the recovery process using a transgenic mouse model. Depletion of CD206⁺ M2-like macrophages or deletion of CD206⁺ M2-like macrophages-specific TGF-β1 gene induces myogenesis and muscle regeneration. We show that depletion of CD206⁺ M2-like macrophages activates FAPs and activated FAPs secrete follistatin, a promyogenic factor, thereby boosting the recovery process. Conversely, deletion of the FAP-specific follistatin gene results in impaired muscle stem cell function, enhanced fibrosis, and delayed muscle regeneration. Mechanistically, CD206⁺ M2-like macrophages inhibit the secretion of FAP-derived follistatin via TGF-β signaling. Here we show that CD206⁺ M2-like macrophages constitute a microenvironment for FAPs and may regulate the myogenic potential of muscle stem/satellite cells.

Hyodeoxycholic Acid (HDCA) Prevents Development of Dextran Sulfate Sodium (DSS)-Induced Colitis in Mice: Possible Role of Synergism between DSS and HDCA in Increasing Fecal Bile Acid Levels

Secondary bile acids (SBAs) with high hydrophobicity are abundant in the colonic lumen. However, both aggravating and protective roles of SBAs have been proposed in the pathogenesis of inflammatory bowel diseases (IBDs). We observed that oral administration of hyodeoxycholic acid (HDCA), a hydrophilic bile acid, prevented the development of dextran sulfate sodium (DSS)-induced colitis in mice. We then examined the individual effects of DSS and HDCA as well as their combined effects on fecal bile acid profile in mice. HDCA treatment increased the levels of most of fecal bile acids, whereas DSS treatment had limited effects on the levels of fecal bile acids. The combined treatment with DSS and HDCA synergistically increased the levels of fecal chenodeoxycholic acid (CDCA) and deoxycholic acid (DCA) in feces, which are potent activators of the farnesoid X receptor (FXR) and Takeda G-protein-coupled receptor 5 (TGR5). The overall hydrophobicity of fecal bile acids was not modified by any treatments. Our data suggest that the preventive effect of HDCA on DSS-induced colitis in mice is due to the synergism between DSS and HDCA in increasing the levels of the fecal bile acids with potencies to activate FXR and TGR5.

Pathological Evaluation of Resected Colorectal Liver Metastases: mFOLFOX6 Plus Bevacizumab versus mFOLFOX6 Plus Cetuximab in the Phase II ATOM Trial

We compared the preplanned histopathological responses of resected liver metastases from patients who received modified FOLFOX6 plus bevacizumab or modified FOLFOX6 plus cetuximab for liver-limited colorectal metastases in the ATOM trial. Fibrosis and viable tumor cells in tumor regression grade (TRG), infarct-like necrosis in modified TRG (mTRG), and dangerous halo (DH) were assessed. Fifty-five patients (28 and 27 patients in the bevacizumab and cetuximab arms, respectively) were divided into the low (viable tumor cells ≤ 50%) and high (>50%) TRG or mTRG groups. DH was characterized as absent/rare or focal/diffuse. Compared to the bevacizumab arm, the cetuximab arm was more effective, with respect to low TRG (13 vs. 23 patients) and absent/rare DH (14 vs. 19 patients), respectively. Low mTRG was similarly observed in both arms. Low TRG/mTRG and absent/rare DH showed better relapse-free survival (RFS) than high TRG/mTRG and focal/diffuse DH. In the bevacizumab arm, a significant difference in RFS existed between the low and high TRG groups, while in the cetuximab arm, for TRG, mTRG, and DH, the low and absent/rare groups demonstrated significantly longer RFS than the high and focal/diffuse groups, respectively. TRG could estimate RFS in patients who underwent liver metastasectomy after bevacizumab or cetuximab chemotherapy.

A 47-Year-Old Man with Advanced Distal Pancreatic Carcinoma and an Initial Partial Response to Chemotherapy Requiring Celiac Axis Reconstruction of the Common Hepatic Artery and Left Gastric Artery

Patient: Male, 47-year-old

Final Diagnosis: Pancreatic adenocarcinoma

Symptoms: Loss of appetite

Medication: —

Clinical Procedure: —

Specialty: Surgery

Sebaceous adenoma occurring within an intracranial dermoid cyst

Among intracranial cystic lesions, dermoid cysts and epidermoid cysts are relatively common benign tumors. In a small number of these tumors, it is known that squamous cell carcinomas arise in the lining epithelium of the cysts. Among tumors derived from the appendage, only one case of hidradenoma within a dermoid cyst and no cases of sebaceous tumor have been reported previously. In the present case, a protruding lesion was present in the cystic wall, and it was composed of two cell types: sebaceous cells (sebocytes) and basaloid/germinated cells, being characteristic of this tumor. It is essential to distinguish it from other sebaceous lesions such as hyperplasia, sebaceoma, sebaceous carcinoma, and basal cell carcinoma with sebaceous differentiation derived from the epidermis. The critical distinguishing points in making a differential diagnosis among these lesions are the ratio of the two cell types and the presence or absence of other components such as hair sacs, invasion or cellular atypia. Immunohistochemical examination revealed that the tumor cells were positive for the epithelial markers, such as cytokeratin (CK)14, p63, p40, high-molecular CK, and adipophilin; these findings are peculiar to sebaceous adenoma. Although there have been several similar case reports of sebaceous tumors associated with dermmoid cysts in the ovaries, most of the intracranial lesions were squamous cell carcinomas that developed within the cysts, and there has been no precedent showing an association with a sebaceous tumor. The present report describes the first case of sebaceous adenoma that occurred in an intracranial dermoid cyst.

Macroscopic visible core length can predict the histological sample quantity in endoscopic ultrasound-guided tissue acquisition: Multicenter prospective study

OBJECTIVES

Measurement of the macroscopic visible core (MVC) length during macroscopic on-site quality evaluation (MOSE) may allow estimation of sample adequacy for next-generation sequencing (NGS), and prediction of correct diagnosis in endoscopic ultrasound-guided tissue acquisition (EUS-TA) of pancreatic masses.

METHODS

This multicenter prospective study included consecutive patients who underwent EUS-TA for pancreatic masses using a 22-G Franseen needle. MVC length and pathological samples obtained from two needle passes were analyzed on a per-pass basis. Outcome measures included respective correlations of MVC length with histological sample quantity and diagnostic yields.

RESULTS

The analysis included 204 passes from 102 EUS-TAs. MVC length correlated positively with histological sample quantity (P < 0.01). On the receiver operating characteristic curve for MVC length, the cut-off value and area under the curve for obtaining a candidate sample for NGS were 30 mm and 0.74 (95% confidence interval [CI] 0.65-0.83), respectively. On multivariate analysis, MVC length ≥30 mm was a significant factor affecting suitability for NGS (odds ratio 6.19; 95% CI 2.72-14.10). Histologic diagnostic yield correlated positively with MVC length (P = 0.01); however, there was no positive correlation between MVC length and overall (histology plus cytology) diagnostic yield.

CONCLUSIONS

Measuring MVC length to predict histological sample quantity on MOSE may be of clinical significance during EUS-TA using a 22-G Franseen needle. It may be an effective method, particularly while submitting samples for NGS.

REGISTRATION

University Hospital Medical Information Network Trials Registry (UMIN000036528).

A Case of Dedifferentiated Melanoma With Lymph Node Metastasis Where Molecular Biological Tests Were Useful for Diagnosis

Malignant melanoma is known to have an altered phenotype and loss of differentiation markers for melanoma due to metastasis. Here, we report a case in which the expression of the immunohistochemical markers for melanoma was changed due to lymph node metastasis of primary cutaneous malignant melanoma. The patient, a male in his 60s, was diagnosed with malignant melanoma after undergoing excision of a skin mass. The additional excision specimen showed a small number of tumor cell clusters infiltrating the dermis. The biopsied lymph node showed completely different histological findings from those of the skin lesion and consisted of spindle-shaped tumor cells. An immunohistochemical study revealed no significant positive reactions in the lymph node tissue indicative of melanoma. The additional genetic study revealed BRAF V600e mutations in both the primary tumor and a lymph node. Together with the histological findings, the diagnosis was of metastasis of dedifferentiated melanoma to a lymph node. In summary, there is a risk of underestimation or misdiagnosis of melanoma as undifferentiated sarcoma or other tumors when melanoma metastasizes to lymph nodes and findings show a dedifferentiated or undifferentiated tumor. Therefore, as in this case, it is necessary to add a genetic study in order to make a comprehensive judgment.

Interleukin-32 regulates downstream molecules and promotes the invasion of pancreatic cancer cells

Pancreatic cancer is a malignant neoplasm with high invasiveness and poor prognosis. In a previous study, a highly invasive pancreatic cancer cell line was established and found to feature enhanced interleukin-32 (IL-32) expression. However, whether IL-32 promotes the invasiveness by enhancing or suppressing the expression of IL-32 through regulating downstream molecules was unclear. To investigate the effect of IL-32, cells were established with high levels of expression or downregulated IL-32; their invasive ability was measured using a real-time measurement system and the expression of some candidate downstream molecules involved in invasion was evaluated in the two cell types. The morphological changes in both cell types and the localization of IL-32 expression in pancreatic cancer tissues were studied using immunohistochemistry. Among the several splice variants of IL-32, cells transfected with the ε isoform had increased invasiveness, whereas the IL-32-suppressed cells had reduced invasiveness. Several downstream molecules, whose expression was changed in the two cell types, were monitored. Notably, changes of E-cadherin, CLDN1, CD44, CTGF and Wnt were documented. The morphologies of the two cell types differed from the original cell line. Immunohistochemically, the expression of IL-32 was observed only in tumor cells and not in normal pancreatic cells. In conclusion, IL-32 was found to promote the invasiveness of pancreatic cancer cells by regulating downstream molecules.

Localized Amyloidosis of the Nasal Mucosa: A Case Report and Review of the Literature

Amyloidosis is a disorder of protein folding in which various proteins automatically aggregate into a highly abnormal fibrillar conformation. Amyloidosis is classified into systemic and localized forms depending on whether the abnormal proteins deposited in several different organs or only a single organ. In localized amyloidosis of the head and neck regions, laryngeal amyloidosis is common; however, localized amyloidosis of the nose is extremely rare. We herein report a case of localized amyloidosis of the nose and review the relevant literature on localized sinonasal amyloidosis. A 41-year-old man presented with a history of severe nasal obstruction, which had persisted for two decades. Nasal endoscopy and imaging studies showed extensive thickening of the bilateral nasal mucosa and diffuse submucosal deposition of calcification. After histopathological and systemic examinations, he was diagnosed with localized amyloidosis of the nasal mucosa. Septoplasty and bilateral inferior turbinoplasty, which consisted of mucosal resection using an ultrasonic bone curette, was performed and his symptoms markedly improved. Localized sinonasal amyloidosis has a good prognosis and surgical resection should be selected as a first-line treatment; however, clinicians should recognize the high probability of recurrence.

Utility of Ethylene-Diamine-Tetraacetic Acid Buffer Solution With Boric Acid for Immunostaining of Specimens Stored for an Extended Period

Antigen modification and denaturation are recognized causes of false negatives in immunostaining. Specimens that have been stored for an extended period at room temperature show decreased immunoreactivity and may mislead the diagnosis. Studies of the molecular targeting of drugs often involve immunostaining of previous samples and, in some situations, only unstained specimens can be used. The present study aimed to develop an effective staining method to recover antigen activation in unstained specimens stored for an extended period by using ethylene-diamine-tetraacetic acid (EDTA) buffer solution with boric acid. We compared several commonly used antigen retrieval solutions and found that Tris-borate-EDTA (TBE) buffer solution with a pH ≥8.3 provided sufficient antigen retrieval. However, pH values higher than 8.3 (9.0, 10.0, and 11.0) frequently caused severe tissue damage. Thus, TBE with pH 8.3 was the most suitable antigen retrieval solution for recovering the antigenicity of specimens stored for an extended period. This procedure may allow useful immunohistochemical information, even from sections that have been stored for an extended period.

The potential diagnostic significance of crypt differentiation in gastric dysplasia

AIMS

This study investigated the relationship between the differentiation of tumour cells into crypts, which is determined by cell differentiation into Paneth and neuroendocrine cells, and tumour infiltration in gastric dysplasia.

METHODS AND RESULTS

The lesions were endoscopically biopsied low-grade dysplasia (LGD), endoscopically resected high-grade dysplasia (HGD), or cancer with submucosal invasion. LGD (n = 32) displayed crypt differentiation across the entire width of the tumour in all cases. Crypt differentiation was identified as a characteristic of tumours with low biological malignancy. HGD (n = 40) included tumours with a mixture of areas with and without crypt differentiation (n = 25) and tumours with crypt differentiation throughout the entire width (n = 15). Of the cancers with submucosal invasion (n = 30), the morphological progression of HGD area with crypt differentiation, HGD area without crypt differentiation and invasive cancer without crypt differentiation was confirmed for 23 samples. In two lesions, invasive cancer without crypt differentiation developed from HGD without crypt differentiation throughout the tumour width. In five samples, well-differentiated tubular adenocarcinoma with crypt differentiation developed from HGD with crypt differentiation and invaded with lamina propria-like stroma.

CONCLUSIONS

Loss of crypt differentiation could be an objective indicator of infiltration in the progression of HGD to invasive cancer. The invasive potential of dysplasia depends on the presence or absence of crypt differentiation.

Central mucoepidermoid carcinoma of the maxilla developing from a calcifying odontogenic cyst: A rare case report

Intraosseous mucoepidermoid carcinoma of the jaw is a rare lesion that has been suggested to originate from the odontogenic epithelium. We report an unusual case of central mucoepidermoid carcinoma in an 18-year-old Japanese man with an odontogenic cyst.

Fate of adipocyte progenitors during adipogenesis in mice fed a high-fat diet

Objective

Expansion of adipose tissue during obesity through the recruitment of newly generated adipocytes (hyperplasia) is metabolically healthy, whereas that through the enlargement of pre-existing adipocytes (hypertrophy) leads to metabolic complications. Accumulating evidence from genetic fate mapping studies suggests that in animal models receiving a high-fat diet (HFD), only adipocyte progenitors (APs) in gonadal white adipose tissue (gWAT) have proliferative potential. However, the proliferative potential and differentiating capacity of APs in the inguinal WAT (iWAT) of male mice remains controversial. The objective of this study was to investigate the proliferative and adipogenic potential of APs in the iWAT of HFD-fed male mice.

Methods

We generated PDGFRα-GFP-Cre-ER^T2/tdTomato (KI/td) mice and traced PDGFRα-positive APs in male mice fed HFD for 8 weeks. We performed a comprehensive phenotypic analysis, including the histology, immunohistochemistry, flow cytometry, and gene expression analysis, of KI/td mice fed HFD.

Results

Contrary to the findings of others, we found an increased number of newly generated tdTomato⁺ adipocytes in the iWAT of male mice, which was smaller than that observed in the gWAT. We found that in male mice, the iWAT has more proliferating tdTomato⁺ APs than the gWAT. We also found that tdTomato⁺ APs showed a higher expression of Dpp4 and Pi16 than tdTomato⁻ APs, and the expression of these genes was significantly higher in the iWAT than in the gWAT of mice fed HFD for 8 weeks. Collectively, our results reveal that HFD feeding induces the proliferation of tdTomato⁺ APs in the iWAT of male mice.

Conclusion

In male mice, compared with gWAT, iWAT undergoes hyperplasia in response to 8 weeks of HFD feeding through the recruitment of newly generated adipocytes due to an abundance of APs with a high potential for proliferation and differentiation.

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High-fat diet (HFD) increases proliferative APs in iWAT of male mice.

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HFD promotes the recruitment of smaller adipocytes in the iWAT of male mice.

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iWAT expands by recruiting newly-generated adipocytes (hyperplasia) in male mice.

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gWAT expands by enlargement of pre-existing adipocytes (hypertrophy) in male mice.

Comparison of Histological Sample Volumes among Various Endoscopic Ultrasound-Guided Biopsy Needles

Endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) enables easy and accurate pathological assessment. Here, we compared and assessed the area of samples on glass slides for three needle types: a 19-gauge Franseen needle (Acquire, Boston Scientific, Natick, MA, USA), a 22-gauge Franseen needle, and a 19-gauge fine-needle aspiration (FNA) needle (EZ Shot 3 Plus; Olympus, Tokyo, Japan). Among patients with suspected pancreatic cancer, with a ≥20 mm tumor located in the pancreatic body and tail, and who underwent EUS-FNA or FNB between June 2018 and March 2020, 10 were randomly selected to test each needle. The areas of histological tissue and blood clot samples were measured using the BZ-X800 imaging software (Keyence Corporation, Osaka, Japan). Baseline patient characteristics and pathological sample data showed no significant differences among the needles. The 19-gauge Franseen needle obtained significantly more histological tissue samples than the 19-gauge conventional needle (p = 0.010) and 22-gauge Franseen needle (p = 0.008). Conversely, there was no significant difference between the 19-gauge conventional needle and 22-gauge Franseen needle (p = 0.838) in this regard. The 19-gauge Franseen needle could collect more samples than the other needles, contributing to giving a more precise pathological diagnosis and more information, including genomic profiling.

Intramural cyst originating from Luschka's duct in the gall bladder: A case report

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A case of the intramural cyst of the gallbladder is rarely encountered.

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The cyst derived from the Luschka duct, a specific histological element of the gallbladder, has not received much attention.

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The gallbladder’s mural cyst, which is derived from the Luschka duct, is different from Rokitansky-Aschoff sinus origin.

Introduction and importance

An intramural cyst is a rare lesion that develops in the wall of the gallbladder. Although the acquired cysts originate from the Rokitansky-Aschoff sinus (RAS), the congenital them, such as the duct of Luschka, are rare. Luschka's duct is a unique and specific tissue component that is histologically different from the inherent bile duct and without the communication to the lumen of the gallbladder.

Case presentation

A woman in her seventies underwent cholecystectomy for the treatment of repeated choledocholithiasis. Pathological examination of the resected specimen revealed multiple cysts in the subserosal tissue of the liver bed. The cysts were lined by cuboidal epithelium and surrounded by hypercellular fibrous tissue. Apart from the Luschka's ducts scattered around the cyst, no other components were observed. Immunohistochemically, the cystic epithelium was different from that of the gallbladder and phenotypically similar to that of the Luschka's duct.

Discussion

From histopathological and immunohistological findings, it was suggested that the cysts of the present case are not derived from RAS, which is the most common in the gallbladder, but from the Luschka’s duct.

Conclusion

We report an extremely rare case of intramural cysts that appear to have originated from the Luschka’s duct.

A case of pancreatic arteriovenous malformation caused acute pancreatitis

Arteriovenous malformation (AVM) in the pancreas rarely causes acute pancreatitis. However, even when it does cause pancreatitis, the pathogenesis is unclear. A 61-year-old man was admitted to our hospital for acute pancreatitis. The findings of computed abdominal tomography, magnetic resonance imaging, and endoscopic ultrasonography revealed pancreatic AVM and hematoma in the tail of the pancreas. These lesions were suspected to be associated with pancreatitis. Although endoscopic retrograde pancreatography could not confirm hemosuccus pancreaticus, distal pancreatectomy was performed because of repeated pancreatitis. The histopathological findings of the resected specimen revealed rupture of the AVM vessels into the main pancreatic ducts. Finally, we considered that intermittent bleeding due to AVM rupture and hematoma formation in the main pancreatic duct caused the repeated pancreatitis.

A case of wild-type transthyretin cardiac amyloidosis with rheumatoid arthritis

A 72-year-old woman was diagnosed with rheumatoid arthritis (RA) 6 years ago and was referred to our hospital for the management of RA. She achieved remission with methotrexate, and her arthritis was well-controlled. Two years ago, a routine, preoperative check-up revealed left ventricular hypertrophy. One month before the current admission, she experienced worsening heart failure, and echocardiography and other findings suggested cardiac amyloidosis as the underlying cause. She was then admitted to our hospital. Biopsies of both the myocardium and duodenum showed amyloid deposits, and the initial immunohistochemical examination suggested amyloid A (AA) amyloidosis, as the deposits were slightly positive to anti-AA antibody and were sensitive to potassium permanganate pre-treatment. Thus, cardiac and duodenal AA amyloidosis secondary to RA was considered. However, the patient had no renal lesions and her RA was strictly controlled, findings atypical of AA amyloidosis. On repeat immunohistochemical testing, the cardiac and duodenal samples were negative for AA but stained positive for transthyretin (TTR). The diagnosis of a wild-type TTR amyloidosis (ATTRwt) was confirmed on the basis of an absence of the TTR gene mutation. The patient was successfully treated with diuretics and enalapril, and tafamidis (potent and selective TTR stabiliser). A pacemaker was implanted for concomitant complete atrioventricular block. This case is the first reported case of systemic ATTRwt complicated by RA. The treatment strategy for amyloidosis differs greatly depending on the type of amyloid deposition. Therefore, it is important to properly identify the amyloid protein, even if the diagnosis is complicated by RA.