Inflammatory myofibroblastic tumor of the prostate

Introduction

Inflammatory myofibroblastic tumors are borderline malignant soft tissue tumors primarily affecting the lungs and pelvic organs. This report presents a rare case of an inflammatory myofibroblastic tumor originating from the prostate gland in a young male.

Case presentation

A 20-year-old man developed gross hematuria and dysuria, revealing a prostatic mass. Pathological examination of a biopsy displayed spindle-shaped myofibroblast proliferation and an infiltrate of inflammatory cells, leading to a diagnosis of inflammatory myofibroblastic tumor. Following fertility preservation measures, the patient underwent a robot-assisted laparoscopic total prostatectomy with bilateral nerve sparing, resulting in a postoperative diagnosis of inflammatory myofibroblastic tumor. No recurrence was observed in subsequent imaging, and urinary continence was maintained.

Conclusion

Surgical resection appears effective in managing inflammatory myofibroblastic tumors of the prostate. This case underscores the importance of complete tumor resection due to the significant recurrence risk associated with inflammatory myofibroblastic tumors. Radical total prostatectomy emerges as a potential treatment strategy for prostate originating inflammatory myofibroblastic tumors.

Performance of Ultra-Rapid Idylla™ EGFR Mutation Test in Non-Small-Cell Lung Cancer and Its Potential at Clinical Molecular Screening

BACKGROUND

The Idylla™ EGFR Mutation Test is an ultra-rapid single-gene test that detects epidermal growth factor receptor (EGFR) mutations using formalin-fixed paraffin-embedded specimens. Here, we compared the performance of the Idylla EGFR Mutation Test with the Cobas^® EGFR Mutation Test v2.

METHODS

Surgically resected NSCLC specimens obtained at two Japanese institutions (N = 170) were examined. The Idylla EGFR Mutation Test and the Cobas EGFR Mutation Test v2 were performed independently and the results were compared. For discordant cases, the Ion AmpliSeq Colon and Lung Cancer Research Panel V2 was performed.

RESULTS

After the exclusion of five inadequate/invalid samples, 165 cases were evaluated. EGFR mutation analysis revealed 52 were positive and 107 were negative for EGFR mutation in both assays (overall concordance rate: 96.4%). Analyses of the six discordant cases revealed that the Idylla EGFR Mutation Test was correct in four and the Cobas EGFR Mutation Test v2 was correct in two. In a trial calculation, the combination of the Idylla EGFR Mutation Test followed by a multi-gene panel test will reduce molecular screening expenses if applied to a cohort with EGFR mutation frequency >17.9%.

CONCLUSIONS

We demonstrated the accuracy and potential clinical utility of the Idylla EGFR Mutation Test as a molecular screening platform in terms of turnaround time and molecular testing cost if applied to a cohort with a high EGFR mutation incidence (>17.9%).

Utility of contrast-enhanced harmonic EUS for diagnosis of portal vein invasion by pancreatic cancer

Background

The value of contrast-enhanced harmonic EUS (CH-EUS) for diagnosis of portal vein invasion in patients with pancreatic cancer was evaluated.

Patients and Methods

This single-center, retrospective study included consecutive patients with pancreatic cancer who underwent both surgical resection after preoperative EUS, CH-EUS, and contrast-enhanced computed tomography (CE-CT) examinations between April 2015 and August 2017. CH-EUS evaluation was performed during the late phase. Portal vein invasion on EUS and CH-EUS was defined as no continuity in the line of the vessel wall. Definition of portal vein invasion on CE-CT was based on the Loyer's criteria. The accuracy of three modalities for diagnosis of invasion into the portal vein was compared using the McNemar's test.

Results

Eighty-eight patients (mean age: 71.0 years, ratio of male to female: 48:40) were eligible. Postoperative pathological results were as follows: seven cases of portal vein invasion; 81 cases without. Diagnostic accuracy of EUS, CH-EUS, and CE-CT for diagnosing invasion into the portal vein was 72.7%, 93.2%, and 81.8%, respectively. The differences between CH-EUS and CE-CT (P = 0.0094) and CH-EUS and EUS (P = 0.0022) were significant. EUS and CE-CT were comparable.

Conclusion

CH-EUS is useful for diagnosis of portal vein invasion by pancreatic cancer.

Performance of Idylla™ RAS-BRAF mutation test for formalin-fixed paraffin-embedded tissues of colorectal cancer

BACKGROUND

The Biocartis Idylla^™ platform is a fully automated, real-time PCR-based diagnostic system. The Idylla^™ KRAS and NRAS-BRAF Mutation Tests have been developed for the qualitative detection of mutations in KRAS, NRAS and BRAF genes, facilitating the genomic profiling of patients with colorectal cancer. The aim of the present study was to evaluate clinical performances of these tests in Japan.

METHODS

The RAS and BRAF mutation statuses of 253 formalin-fixed paraffin-embedded (FFPE) colorectal cancer tissues were analyzed using the Investigational Use Only Idylla^™ KRAS Mutation Test and the Idylla^™ NRAS-BRAF Mutation Test and an in vitro diagnostics (IVD) kit (MEBGEN RASKET^™-B kit).

RESULTS

The success rate for obtaining a valid mutational data without retest of the Idylla tests was 97.6% (247/253): 111 KRAS mutations (43.8%), 9 NRAS mutations (3.6%), and 36 BRAF V600E mutations (14.2%) were detected using the Idylla tests. Compared with the MEBGEN RASKET-B results, the positive concordance rate was 97.4%, the negative concordance rate was 95.7%, and the overall concordance rate was 95.3% (κ = 0.919, 95% CI 0.871-0.967). The average turnaround time to Idylla^™ KRAS and NRAS-BRAF Mutation Test was 5.6 working days (range: 3-11 days).

CONCLUSION

This result demonstrates a high concordance between the Idylla^™ KRAS and NRAS-BRAF Mutation Tests and an existing IVD kit. In this manner, the Idylla^™ mutation tests were validated for the detection of clinically significant KRAS, NRAS, and BRAF mutations in FFPE samples from colorectal cancer patients.

Intestinal Microbiota and Gene Expression Reveal Similarity and Dissimilarity Between Immune-Mediated Colitis and Ulcerative Colitis

Immune checkpoint inhibitors (ICIs) have become the standard of care for several cancers. However, ICI therapy has also been associated with various immune-related adverse events (irAEs). Clinical manifestations of immune-related colitis resemble those of inflammatory bowel diseases such as ulcerative colitis (UC). The composition of the bowel microflora is thought to influence the development of inflammatory bowel disease and irAE colitis. We profiled the gene expressions and microbe compositions of colonic mucosa from patients with solid cancers receiving anti-PD-L1 antibody treatment; we then compared the expression profiles associated with irAE colitis with those associated with UC. The pathway enrichment analysis revealed functional similarities between inflamed regions of irAE colitis and UC. The common enriched pathways included leukocyte extravasation and immune responses, whereas non-inflamed mucosa from patients with irAE colitis was distinct from patients with UC and was characterized by the recruitment of immune cells. A similarity between the microbiota profiles was also identified. A decreased abundance of Bacteroides species was observed in inflamed regions from both irAE colitis and UC based on a microbiota composition analysis of 16S rDNA sequencing. Pathways associated with molecule transport systems, including fatty acids, were enriched in inflamed and non-inflamed irAE colitis and inflamed UC, similar to Piphillin-inferred KEGG pathways. While UC is characterized by local regions of inflammation, ICI treatment extends to non-inflammatory regions of the colonial mucosa where immune cells are reconstituted. This analysis of the similarity and heterogeneity of irAE colitis and UC provides important information for the management of irAE colitis.

Effects of Inadequate Folate Intake on the Onset and Progression of Hypertensive Vascular Injury

We investigated the effects of inadequate folate intake on the onset and progression of hypertensive organ injury. In the present study, 5-wk-old male stroke-prone spontaneously hypertensive rats (SHRSP) were fed with a normal-folate (control; 160-170 μg of folate/100 g diet) or low-folate (8-10 μg of folate/100 g diet) diet until they reached 25 wk of age. After the animals reached 10 wk of age, the bodyweight of the rats in the low-folate group was lower than that of the rats in the control group. Regarding blood pressure, both groups had severe hypertension of ≥230 mmHg at 12 wk of age that was not significantly different between the groups. At 16 wk of age, the low-folate group had a low number of blood cell types. The folate levels in the serum, liver, and kidneys of these rats were significantly lower (p<0.01) and the serum homocysteine level in the low-folate group was significantly higher than in the controls. The low-folate group had a significantly lower testicular weight than the control group (p<0.05) and arterial hypertrophy, spermatogenesis arrest, and interstitial connective tissue hyperplasia were observed. However, there was no clear difference in lesions in other organs. These results indicated that under low folate status, SHRSP causes hematopoietic disorders and exacerbates hypertensive vascular injury at various degrees by organ type.

Analysis of Progression Time in Pancreatic Cancer including Carcinoma In Situ Based on Magnetic Resonance Cholangiopancreatography Findings

BACKGROUND

Pancreatic cancer (PC) exhibits extremely rapid growth; however, it remains largely unknown whether the early stages of PC also exhibit rapid growth speed equivalent to advanced PC. This study aimed to investigate the natural history of early PCs through retrospectively assessing pre-diagnostic images.

METHODS

We examined the data of nine patients, including three patients with carcinoma in situ (CIS), who had undergone magnetic resonance cholangiopancreatography (MRCP) to detect solitary main pancreatic duct (MPD) stenosis >1 year before definitive PC diagnosis. We retrospectively analyzed the time to diagnosis and first-time tumor detection from the estimated time point of first-time MPD stenosis detection without tumor lesion.

RESULTS

The median tumor size at diagnosis and the first-time tumor detection size were 14 and 7.5 mm, respectively. The median time to diagnosis and first-time tumor detection were 26 and 49 months, respectively.

CONCLUSIONS

No studies have investigated the PC history, especially that of early PCs, including CIS, based on the initial detection of MPD stenosis using MRCP. Assessment of a small number of patients showed that the time to progression can take several years in the early PC stages. Understanding this natural history is very important in the clinical setting.

Soft Tissue Myoepithelioma of the Shoulder

Soft tissue myoepitheliomas are often misdiagnosed due to their rarity. Herein, we describe a case of soft tissue myoepithelioma of the shoulder. A 72-year-old woman had a suspected sarcoma on her shoulder and under-went open biopsy. She was referred to our hospital, where the tumor was widely resected and the diagnosis of myoepithelioma was histologically confirmed. No recurrence has been observed in the 3 years since the sur-gery. Careful and prompt planning is necessary for the effective treatment of myoepithelioma.

Utility of contrast-enhanced harmonic endoscopic ultrasonography for T-staging of patients with extrahepatic bile duct cancer

BACKGROUND

The value of contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) for T-staging in patients with extrahepatic bile duct cancer was evaluated.

METHODS

This single-center, retrospective study included consecutive patients with extrahepatic bile duct cancer who underwent surgical resection after preoperative EUS, CH-EUS, and contrast-enhanced CT (CE-CT) examinations between June 2014 and August 2017. The capacity of these modalities for T-staging of extrahepatic bile duct cancer was evaluated by assessing invasion beyond the biliary wall into the surrounding tissue, gallbladder, liver, pancreas, duodenum, portal vein system (portal vein and/or superior mesenteric vein), inferior vena cava, and hepatic arteries (proper hepatic artery, right. and/or left. hepatic artery). Blind reading of EUS, CH-EUS, and CE-CT images was performed by two expert reviewers each.

RESULTS

38 patients were eligible for analysis, of which eight had perihilar bile duct cancer and 30 had distal bile duct cancer. Postoperative T-staging was T1 in 6, T2 in 16, and T3 in 16 cases. CH-EUS was superior to CE-CT for diagnosing invasion beyond the biliary wall into surrounding tissue (92.1% vs. 45.9%, P = 0.0002); the ability to detect invasion to other organs did not differ significantly between the two modalities. The accuracy of CH-EUS for T-staging of tumors was better than that of CE-CT (73.7% vs. 39.5%, P = 0.0059). CH-EUS tended to have a better accuracy than EUS for the diagnosis of invasion beyond the biliary wall into the surrounding tissue (92.1% vs. 78.9%, P = 0.074) and T-staging (73.7% vs. 60.5%, P = 0.074).

CONCLUSION

CH-EUS is useful for T-staging of extra hepatic bile duct cancer, especially in terms of invasion beyond the biliary wall into the surrounding tissue.

Utility of contrast-enhanced harmonic endoscopic ultrasonography for predicting the prognosis of pancreatic neuroendocrine neoplasms

BACKGROUND AND AIMS

Pancreatic neuroendocrine neoplasms (PanNENs), including Grade 1 (G1) or G2 tumors, can have a poor prognosis. This study investigated the value of contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) for predicting the prognosis of PanNENs.

METHODS

This single-center, retrospective study included 47 consecutive patients who underwent CH-EUS and were diagnosed with PanNEN by surgical resection or EUS-guided fine needle aspiration between December 2011 and February 2016. Patients were divided into aggressive and non-aggressive groups according to the degree of clinical malignancy. CH-EUS was assessed regarding its capacity for diagnosing aggressive PanNEN, the correspondence between contrast patterns and pathological features, and its ability to predict the prognosis of PanNEN.

RESULTS

There were 19 cases of aggressive PanNEN and 28 cases of non-aggressive PanNEN. The aggressive group included three G1, four G2, three G3 tumors, three mixed neuroendocrine non-neuroendocrine neoplasms, and six neuroendocrine carcinomas. CH-EUS was superior to contrast-enhanced computed tomography for the diagnosis of aggressive PanNEN (P < 0.001): hypo-enhancement on CH-EUS was an indicator of aggressive PanNEN, with sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 94.7%, 100%, 100%, 96.6%, and 97.9%, respectively. Among G1/G2 PanNENs, cases with hypo-enhancement on CH-EUS had a poorer prognosis than those with hyper/iso-enhancement (P = 0.0009). Assessment of 36 resected specimens showed that hypo-enhancement on CH-EUS was associated with smaller and fewer vessels and greater degree of fibrosis.

CONCLUSION

Contrast-enhanced harmonic endoscopic ultrasonography may be useful for predicting the prognosis of PanNENs.

Case Report: Concurrent Occurrence of Abdominal Double Expressor Lymphoma and Jejunum Follicular Lymphoma

Double expressor lymphoma (DEL), defined as overexpression of BCL2 and MYC, is an aggressive subtype of diffuse large B cell lymphoma (DLBCL). Here we report a case of a 64-year-old female diagnosed with abdominal DEL transformed from jejunum follicular lymphoma (FL). 18F-fluorodeoxyglucose (FDG)-positron emission tomography showed diffuse accumulation of FDG into the peritoneum and small bowel wall. Double balloon-assisted enteroscopy revealed whitish submucosal tumors in the proximal jejunum. Aggregation of atypical lymphocytes positive for CD20, CD79a, and BCL2 was seen in the jejunal biopsy samples. These atypical lymphocytes were monoclonal since cell surface expression of Ig light chains was limited to κ chain by flow-cytometry. Thus, immunohistochemical and flowcytometric analyses data were consistent with FL of the jejunum. Neoplastic lymphocytes obtained from ascites were positive for CD10, CD20, CD79a, BCL2, and BCL6. Fluorescence in situ hybridization (FISH) showed formation of BCL2/IgH fusion gene and extra copies of MYC, the former of which is a characteristic chromosomal abnormality of FL. These genetic alterations and protein expression profiles of ascitic fluid cells were consistent with those of DEL transformed from FL. Given that a significant population of patients with indolent FL of the gastrointestinal tract developed into aggressive DLBCL, it is likely that primary FL of the jejunum transformed into the abdominal aggressive DEL in this case. This case is unique in that concurrent occurrence of FL and DEL was confirmed by immunohistochemical and FISH analyses and that abdominal DEL transformed from jejunal FL was highly suspected.

Case Report: A Case of Intestinal Behçet's Disease Exhibiting Enhanced Expression of IL-6 and Forkhead Box P3 mRNA After Treatment With Infliximab

Behçet's disease (BD) is a rare inflammatory condition characterized by oral and genital ulcers, skin lesions, as well as ophthalmological, neurological, and gastrointestinal manifestations. BD involving the gastrointestinal tract is known as intestinal BD. The mucosa of the gastrointestinal tract of patients with intestinal BD exhibits enhanced levels of proinflammatory cytokines, such as IL-1β, IL-6, and TNF-α. These proinflammatory cytokines play pathogenic roles in the development of BD, as evidenced by the fact that biologics targeting these cytokines effectively induce BD remission. It should be noted, however, that the molecular mechanisms by which the blockade of these cytokines suppresses chronic inflammatory responses in BD are poorly understood. Herein, we report a case of intestinal BD resistant to prednisolone that was successfully treated with infliximab (IFX). The induction of remission by IFX was accompanied by a marked elevation of IL-6 and forkhead box P3 (FOXP3) at mRNA level. This case suggests that induction of remission by IFX is mediated not only by the suppression of TNF-α-mediated signaling pathways, but also by the promotion of IL-6 expression and accumulation of regulatory T cells expressing FOXP3.

Integrin-linked kinase pathway in heterogeneous pulmonary sarcomatoid carcinoma

Pulmonary sarcomatoid carcinoma (PSC) is classified as poorly differentiated, and non-small cell lung carcinomas that contained a component of sarcoma or sarcoma-like differentiation are rare. The underlying carcinogenetic mechanism governing PSC remains unclear. The current study investigated the underlying carcinogenetic mechanism of PSC based on the hypothesis that it involves the epithelial-mesenchymal transition (EMT) process. Mutation analysis of PSCs, including carcinosarcoma, pleomorphic carcinoma and epithelial carcinoma specimens, was performed using targeted deep sequencing, whole transcriptome analysis and digital spatial profiling (DSP). PSCs exhibit a distinct mutation profile, with TP53, SYNE1 and APC mutations. Therefore, clustering of the gene expression profiles allowed the PSCs to be distinguished from the epithelial carcinomas. Increased gene expression of fibronectin in PSC was an important contributor to differential profiles. Pathway analysis revealed enhanced activity of the integrin-linked kinase (ILK) signaling pathway in the PSCs. DSP analysis using 56 antibodies of marker proteins confirmed significantly higher expression of fibronectin in PSCs. Intratumor heterogeneity of fibronectin expression was observed in sarcoma components. In conclusion, epithelial-mesenchymal transition process mediated by ILK signaling may be associated with carcinogenetic mechanisms of PSC. Overexpression of fibronectin mediated by ILK signaling appears to serve a role in the EMT involved in the PSC transformation process.

Primary diaphragmatic clear cell carcinoma associated with endometriosis: A case report and literature review

Diaphragmatic endometriosis is extremely rare. Although endometriosis is considered generally benign, malignant transformation of endometriosis was reported in 1925. Multiple studies have since described clear cell carcinoma (CCC) or endometrioid carcinoma arising from ovarian endometriosis. Previously, only two reports of primary diaphragmatic CCC were reported, in which coexistent endometriosis with CCC was not histologically proven. We report a case of a 55-year-old postmenopausal woman who was admitted to Kindai university hospital for the examination of a cystic mass with papillary components in the right diaphragm. On her past medical history, abdominal hysterectomy and bilateral salpingo-oophorectomy was performed for high-grade cervical intraepithelial neoplasia, uterine myoma, and bilateral ovarian endometriosis 5 years ago. Unenhanced CT performed 5 years ago, showed a nodular lesion with low density in the right diaphragm, consistent with diaphragmatic endometriosis. Magnetic resonance imaging during this admission, showed a cystic mass with papillary components in the right diaphragm and a T2*-weighted gradient echo imaging showed partial low signal intensity in the papillary components and cyst wall, which was suspected to represent hemosiderin deposition. Based on these serial images, malignant transformation of diaphragmatic endometriosis was suspected. Under, open abdominal combined resection of the mass and part of the diaphragm was performed. Endometriosis implants were detected on the pelvic peritoneum. Histopathological examination revealed clear cell carcinoma associated with endometriosis and hemosiderin deposition in the cyst wall. T2*-weighted gradient echo imaging was useful in the detection of hemosiderin deposition caused by the coexistent endometriosis. When a cystic mass with papillary components and cyst wall with hemosiderin deposits are encountered on MR images, malignant transformation of endometriosis is suspected and a detailed medical history should be determined and the possibility of concurrent endometriosis or adenomyosis should be investigated, as should the potential existence of diaphragmatic endometriosis in previous images.

Partial Pancreatic Parenchymal Atrophy Is a New Specific Finding to Diagnose Small Pancreatic Cancer (≤10 mm) Including Carcinoma in Situ: Comparison with Localized Benign Main Pancreatic Duct Stenosis Patients

BACKGROUND

This study aimed to evaluate and identify the specific CT findings by focusing on abnormalities in the main pancreatic duct (MPD) and pancreatic parenchyma in patients with small pancreatic cancer (PC) including carcinoma in situ (CIS).

METHODS

Nine CT findings indicating abnormalities of MPD and pancreatic parenchyma were selected as candidate findings for the presence of small PC ≤ 10 mm. The proportions of patients positive for each finding were compared between small PC and benign MPD stenosis groups. Interobserver agreement between two independent image reviewers was evaluated using kappa statistics.

RESULTS

The final analysis included 24 patients with small PC (including 11 CIS patients) and 28 patients with benign MPD stenosis. The proportion of patients exhibiting partial pancreatic parenchymal atrophy (PPA) corresponding to the distribution of MPD stenosis (45.8% vs. 7.1%, p < 0.01), upstream PPA arising from the site of MPD stenosis (33.3% vs. 3.6%, p = 0.01), and MPD abrupt stenosis (45.8% vs. 14.3%, p = 0.03) was significantly higher in the small PC group than in the benign MPD stenosis group.

CONCLUSIONS

The presence of partial PPA, upstream PPA, and MPD abrupt stenosis on a CT image was highly suggestive of the presence of small PCs including CIS.

Ectopic TWEAKR expression in type I fiber of stroke-prone spontaneously hypertensive rats is related to slow muscle-specific hypotrophy

AIMS

Stroke-prone spontaneously hypertensive rats (SHRSP) show significantly lower body weight than normotensive Wistar-Kyoto rats (WKY). Our hypotheses are as follows: weight loss of the skeletal muscle is related to hypertension-related diseases, and muscle hypotrophy is useful as a therapeutic target for hypertension and hypertension-related diseases. In this study, we aimed to investigate the pathophysiological characteristics of muscle hypotrophy in SHRSP to determine the therapeutic target molecule(s).

MAIN METHODS

The difference in skeletal muscles in the lower leg between WKY and SHRSP was evaluated mainly through weight/tibial length, histological, gene expression, and protein expression analyses.

KEY FINDINGS

SHRSP had a significantly lower weight/tibial length in soleus and gastrocnemius, but not in plantaris and tibialis anterior, indicating that muscles consisting of a relatively high amount of slow muscle fiber were affected. This result was confirmed by the histological analysis of soleus, showing that type I fiber mainly decreased the fiber size. Microarray and protein expression analyses showed that the muscle-specific ubiquitin ligase, muscle RING finger 1 (MuRF1), but not atrogin-1, was highly expressed in soleus, but not in plantaris, in SHRSP. TNF-like weak inducer of apoptosis receptor (TWEAKR) was predicted as a MuRF1 up-regulator by Ingenuity Pathway Analysis and immunostained only in type II fiber in WKY but in both type I and II fibers in SHRSP.

SIGNIFICANCE

TWEAKR is a type II-specific receptor in the skeletal muscle. Ectopic TWEAKR expression in type I fiber of SHRSP is most likely involved in slow muscle-specific hypotrophy through MuRF1 overexpression.

Agreement on endoscopic ultrasonography-guided tissue specimens: Comparing a 20-G fine-needle biopsy to a 25-G fine-needle aspiration needle among academic and non-academic pathologists

BACKGROUND AND AIM

A recently carried out randomized controlled trial showed the benefit of a novel 20-G fine-needle biopsy (FNB) over a 25-G fine-needle aspiration (FNA) needle. The current study evaluated the reproducibility of these findings among expert academic and non-academic pathologists.

METHODS

This study was a side-study of the ASPRO (ASpiration versus PROcore) study. Five centers retrieved 74 (59%) consecutive FNB and 51 (41%) FNA samples from the ASPRO study according to randomization; 64 (51%) pancreatic and 61 (49%) lymph node specimens. Samples were re-reviewed by five expert academic and five non-academic pathologists and rated in terms of sample quality and diagnosis. Ratings were compared between needles, expert academic and non-academic pathologists, target lesions, and cytology versus histological specimens.

RESULTS

Besides a higher diagnostic accuracy, FNB also provided for a better agreement on diagnosing malignancy (ĸ = 0.59 vs ĸ = 0.76, P < 0.001) and classification according to Bethesda (ĸ = 0.45 vs ĸ = 0.61, P < 0.001). This equally applied for expert academic and non-academic pathologists and for pancreatic and lymph node specimens. Sample quality was also rated higher for FNB, but agreement ranged from poor (ĸ = 0.04) to fair (ĸ = 0.55). Histology provided better agreement than cytology, but only when a core specimen was obtained with FNB (P = 0.004 vs P = 0.432).

CONCLUSION

This study shows that the 20-G FNB outperforms the 25-G FNA needle in terms of diagnostic agreement, independent of the background and experience of the pathologist. This endorses use of the 20-G FNB needle in both expert and lower volume EUS centers.

A fungal ball within a maxillary sinus with dental root canal filler and rare fungal propagules

A fungal ball of a maxillary sinus sometimes includes dental treatment-related foreign material because the sinus is close to the root of the upper teeth. We present a case of right maxillary sinus fungal ball with a gutta-percha point, a dental root canal filler. X-ray analysis of the foreign material in the paraffin section of the fungal ball successfully detected zinc, sulfur, and barium, all of which were constituents of the gutta-percha point. The gutta-percha point might have facilitated the formation of the fungal ball through disruption of the sinus-clearing mechanism. Another interesting histological feature of the fungal ball was the finding of calcium oxalate crystals and non-hyphal fungal elements such as cleistothecia, Hülle cells, and conidial heads. This is the first report of such a combination being found in a specimen of human fungal disease. Although fungal culture was not available in the present case, molecular analysis of the formalin-fixed paraffin-embedded tissue of the fungal ball succeeded in revealing only DNA sequences of Aspergillus nidulans and some other environmental Aspergillus spp.

A Rare Case of 18F-FDG Uptake in an Ectopic Thyroid Carcinoma of the Anterior Middle Neck Lacking Thyroglossal Duct Remnants

An 80-year old female presented with a well-defined tumor of the anterior middle neck, and a diagnosis of thyroglossal duct cyst was made. When the tumor size increased, malignancy was suspected. Ultrasonography revealed a smooth, heterogeneously hypoechoic area at her anterior neck. Contrast-enhanced computed tomography showed a well-defined contrast-enhanced tumor inferior to the hyoid bone. Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) showed a fluorine-18 fluorodeoxyglucose-avid tumor with a maximum standardized uptake value of 12.8. Surgical tumor resection was performed, and the histopathological finding was ectopic papillary carcinoma lacking thyroglossal duct remnants, which is very rare. To our knowledge, few cases of ectopic thyroid carcinoma with ¹⁸F-FDG PET/CT findings have been reported. Ectopic thyroid carcinoma lacking thyroglossal duct remnants should be considered a differential diagnosis in cases of ¹⁸F-FDG uptake in an anterior middle neck tumor.

Spontaneously infarcted parotid tumours: MRI findings

OBJECTIVES

To report MRI findings of spontaneous infarction in parotid tumours.

METHODS

14 patients (13 male, 1 female; mean age 73 years) with spontaneously infarcted parotid tumours were reviewed retrospectively. MR images were assessed for the location, the presence of synchronous parotid masses, margin characteristics, signal intensity on T ₁ and T ₂ weighted images, and internal architecture according to the distribution of T ₂ signal hyperintensity.

RESULTS

12 tumours were located in the parotid tail and 2 in the superficial lobe. Synchronous parotid masses were seen in four tumours, three of which were located in the ipsilateral parotid tail and one in the contralateral parotid tail. Seven tumours had well-defined margins and seven had ill-defined margins. The signal intensities on T ₁ weighted images were a mixture of high and intermediate in all cases; in 11 tumours, hyperintense areas were dominant. On T ₂ weighted images, all tumours also showed a mixture of high and intermediate signal intensities. Internal architectures on T ₂ weighted images were mosaic hyperintensity in three tumours, central hyperintensity in five, and multiseparated hyperintensity in six.

CONCLUSIONS

Spontaneously infarcted parotid tumours were mostly located in the parotid tail and showed mixed signal intensities with predominant hyperintensity on T ₁ weighted images. Half of the tumours had ill-defined margins, and the internal architectures varied.

A multicenter randomized trial comparing a 25-gauge EUS fine-needle aspiration device with a 20-gauge EUS fine-needle biopsy device

BACKGROUND AND AIMS

Several studies have compared EUS-guided FNA with fine-needle biopsy (FNB), but none have proven superiority. We performed a multicenter randomized controlled trial to compare the performance of a commonly used 25-gauge FNA needle with a newly designed 20-gauge FNB needle.

METHODS

Consecutive patients with a solid lesion were randomized in this international multicenter study between a 25-gauge FNA (EchoTip Ultra) or a 20-gauge FNB needle (ProCore). The primary endpoint was diagnostic accuracy for malignancy and the Bethesda classification (non-diagnostic, benign, atypical, malignant). Technical success, safety, and sample quality were also assessed. Multivariable and supplementary analyses were performed to adjust for confounders.

RESULTS

A total of 608 patients were allocated to FNA (n = 306) or FNB (n = 302); 312 pancreatic lesions (51%), 147 lymph nodes (24%), and 149 other lesions (25%). Technical success rate was 100% for the 25-gauge FNA and 99% for the 20-gauge FNB needle (P = .043), with no differences in adverse events. The 20-gauge FNB needle outperformed 25-gauge FNA in terms of histologic yield (77% vs 44%, P < .001), accuracy for malignancy (87% vs 78%, P = .002) and Bethesda classification (82% vs 72%, P = .002). This was robust when corrected for indication, lesion size, number of passes, and presence of an on-site pathologist (odds ratio, 3.53; 95% confidence interval, 1.55-8.56; P = .004), and did not differ among centers (P = .836).

CONCLUSION

The 20-gauge FNB needle outperformed the 25-gauge FNA needle in terms of histologic yield and diagnostic accuracy. This benefit was irrespective of the indication and was consistent among participating centers, supporting the general applicability of our findings. (Clinical trial registration number: NCT02167074.).

[A Case of Advanced Esophageal Cancer Successfully Treated with Neoadjuvant Chemotherapy Containing 5-FU, Docetaxel. and Nedaplatin Combination Therapy]

A 71-year-old man with a history of hypertension, diabetes mellitus, and cerebral infarction was admitted to our hospital with dysphagia. Gastroduodenoscopy, thoracoabdominal CT, and PET-CT findings showed type 2 advanced esophageal cancer( squamous cell carcinoma)with upper mediastinal and cervical lymph node(LN)metastasis: cT3N2M1(LYM #104L), cStage Ⅳ. Two courses of neoadjuvant UDONchemotherapy containing 5-FU(640mg/m / 2, days 1-5), docetaxel(28mg/m2, days 1 and 15), and nedaplatin(72mg/m2, day 1)were administered every 4 weeks. UDONtherapy caused grade(Gr)3 febrile neutropenia, Gr 2 diarrhea, and Gr 1 thrombopenia; the tumor and LNs partially responded to the therapy. After 2 courses of UDONtherapy, esophagectomy with right thoracotomy, 3-field LNdissection, and reconstruction of the gastric tube were performed. The postoperative course was almost uneventful besides recurrent nerve palsy, aspiration, pneumonia, and delirium, and the patient was discharged 60 days after surgery. The pathological diagnosis was ypT0N0M0, ypStage 0, and the histological response of the primary tumor and LNs were evaluated as Gr 3. Neoadjuvant UDON therapy is feasible for elderly patients with advanced esophageal cancer and renal failure or comorbidities, for whom CDDP could not be administered. We are planning a clinical trial to assess the effectiveness of neoadjuvant UDONtherapy.

Neurilemmoma Mimicking a Multilocular Cystic Lesion of the Liver

Neurilemmomas are benign tumors arising from the sheaths of peripheral nerves. They appear rarely in the abdominal cavity. We herein report an 80-year-old man with a multilocular cystic neurilemmoma mimicking a liver lesion. Preoperative images showed a lesion in the porta hepatis. Although a preoperative diagnosis was difficult, surgery was undertaken because of the possibility of malignancy. Histologically, the tumor consisted of spindle-shaped cells with positivity for S-100 protein. The final diagnosis was a neurilemmoma. Porta hepatic neurilemmomas are rare. When we encounter a multilocular cystic lesion of the liver, neurilemmoma should be considered in the differential diagnosis.

[A Case of Apocrine Carcinoma in the Breast That Was Difficult to Distinguish from Axillary Apocrine Adenocarcinoma]

An 86-year-old woman visited our hospital with a tumor on her right axilla. Ultrasonography(US)showed a 4 cm tumor between mammary gland and axilla with swelling of some lymph nodes. No distant metastatic lesions were found. The pathological findings revealed breast apocrine carcinoma; therefore, we performed total mastectomy and axillary lymph node dissection. The postoperative pathological findings revealed breast apocrine carcinoma with pT4N2M0, Stage Ⅲb(ER positive, PgR negative, HER2 positive, Ki-67 6%). We present a case of breast apocrine carcinoma confused with axially apocrine adenocarcinoma during the diagnosis and report the relevant literature.

[A Case of Breast Cancer with Infarcted Necrosis That Was Diagnosed Based on Axillary Lymph Node Metastasis]

A 61-year-old woman with a breast tumor detected by mammography examination was admitted to our hospital. Ultrasonography showed a 15.5×7.2mm sized irregular mass at the left BD area. Vacuum-assisted biopsy did not reveal any malignant cells. After 3 months, ultrasonography reexamination showed that the irregular mass had increased to 24.2×16.5mm in size, and it had spread to multiple axillary lymph nodes. The patient was diagnosed with breast cancer by core needle biopsy of the axillary lymph node. Total mastectomy with axillary lymph node dissection was performed. The pathological diagnosis was solid-tubular carcinoma with infarcted necrosis. The number of metastatic axillary lymph nodes was confirmed to be 23 in total. This case was considered very rare and important because there have been very few reports of breast cancer with infarcted necrosis.

Dual-energy computed tomography for non-invasive staging of liver fibrosis: Accuracy of iodine density measurements from contrast-enhanced data

AIM

To investigate whether iodine density measurements from contrast-enhanced dual-energy computed tomography (CT) data can non-invasively stage liver fibrosis.

METHODS

This single-center, prospective study was approved by our IRB with written informed consent. Forty-seven consecutive patients (26 men and 21 women; mean age, 63.1 years) with chronic liver disease underwent contrast-enhanced dual-energy CT of the liver (non-contrast, arterial, portal venous, and equilibrium phase images), followed by liver biopsy. Iodine density of liver and aorta were obtained by two independent observers. Iodine uptake of the liver (Δ Liver), representing the difference in iodine density between equilibrium phase and non-contrast images, was calculated and normalized by aorta (Δ Liver/Aorta). We accounted for contrast agent distribution volume by using hematocrit level. Accuracy of iodine density measurements for staging liver fibrosis was assessed by using receiver operating characteristic (ROC) curves. Multivariate linear regression analysis was used to assess the impact of independent variables (liver fibrosis stage and patient-related confounders) on iodine uptake.

RESULTS

The Δ Liver/Aorta significantly increased and moderately correlated with METAVIR liver fibrosis stage (ρ = 0.645, P < 0.001). Areas under the ROC curve ranged from 0.795 to 0.855 for discriminating each liver fibrosis score (≥F1-F4). METAVIR fibrosis stage was the most significant independent factor associated with Δ Liver (P = 0.005) and Δ Liver/Aorta (P < 0.001).

CONCLUSION

Hepatic extracellular volume fraction with contrast-enhanced dual-energy CT can non-invasively stage liver fibrosis in chronic liver diseases. This technique could prove useful for monitoring disease progression and treatment response, potentially reducing the need for liver biopsy.

Value of additional endoscopic ultrasonography for surveillance after surgical removal of intraductal papillary mucinous neoplasms

BACKGROUND AND AIM

This study evaluated the utility of endoscopic ultrasonography (EUS) combined with contrast-enhanced harmonic EUS (CH-EUS) for surveillance of the remnant pancreas after surgery for intraductal papillary mucinous neoplasm (IPMN).

METHODS

This was a single-center, retrospective, descriptive study. A total of 134 consecutive patients who underwent surgical resection for IPMN between April 2009 and March 2015 were evaluated. Rates of recurrence and development of IPMN-concomitant pancreatic ductal adenocarcinoma (PDAC) during follow up were assessed. Clinical findings of patients with recurrence or development of PDAC were also evaluated.

RESULTS

Of 134 resected IPMN 56 (41.8%) and 78 (58.2%) were classified as benign and malignant, respectively. Patients were followed up for a median of 29 months, 33 (24.6%) by both contrast-enhanced computed tomography (CE-CT) and EUS, and 101 (75.4%) by computed tomography (CT) alone. Thirteen patients (9.7%) showed tumor recurrence, five with intra-pancreatic recurrence and eight with extra-pancreatic metastases. An enhancing mural nodule within the dilated main pancreatic duct was successfully detected by EUS in one patient, but not by CE-CT. Two patients developed IPMN-concomitant PDAC during follow up. EUS combined with CH-EUS successfully detected small IPMN-concomitant PDAC in two patients, whereas these lesions were not detected by CT. CH-EUS was useful for better visualization of the margins of IPMN-concomitant PDAC in one of these two patients.

CONCLUSION

Endoscopic ultrasonography combined with CH-EUS may improve follow up of patients with resected IPMN.

Intraductal papillary mucinous neoplasm originating from a heterotopic pancreas within the jejunum: a case report

We report a case of intraductal papillary mucinous neoplasm arising within the heterotopic pancreatic tissue which was found incidentally in the jejunum during surgery for bowel obstruction. A 54-year-old female patient was admitted to our hospital due to sudden abdominal pain. In preoperative findings, we diagnosed bowel obstruction and performed surgery. Intra-operative findings showed adhesive intestinal obstruction, we performed synechiotomy for adhesion release. During surgery, when searching the small intestine, we coincidentally found a tumor in the jejunum and partial resected the jejunum. Pathological examination revealed a 1.2 cm × 1.0 cm × 1.0 cm white yellow nodule with cystic spaces. Histological examination demonstrated heterotopic pancreatic tissue consisting of well-formed lobules of pancreatic acini and cystically dilated ducts containing intraductal papillary neoplasm. Moreover, in immunohistochemical staining, MUC5AC was diffusely expressed, but not MUC1, MUC2 and MUC6.

MR imaging features of mammary analogue secretory carcinoma and acinic cell carcinoma of the salivary gland: a preliminary report

OBJECTIVES

To report MR imaging features of mammary analogue secretory carcinoma (MASC) and acinic cell carcinoma (AciCC) of the salivary gland based on the latest version of the World Health Organization (WHO) 2017 classification of head and neck tumours.

METHODS

MR images in 4 patients with MASC and 4 with AciCC were reviewed for margin characteristics, the presence of pathological cervical nodes, the presence of a cystic component and interface between cystic and solid component, signal intensity of the cystic components on T₁ weighted images, and signal intensity of the solid component on T₁ and T₂ weighted images.

RESULTS

All the MASCs and AciCCs had well-defined boundaries, and 1 AciCC had pathological nodes. All 4 MASCs presented as predominantly cystic tumours with papillary projection of the solid component. All 4 AciCCs presented as solid tumours. The signal intensity of the cystic components on T₁ weighted images was entirely hyperintense in 2, and partly hyperintense demonstrating fluid-fluid level in 2. In all the MASCs, the signal intensity of the solid components on T₁ weighted images was intermediate. In the AciCCs, the signal intensity of the solid components on T₁ weighted images was high in 2 tumours and intermediate in 2. The signal intensity of the solid components on T₂ weighted images varied from low to high in both MSACs and AciCCs.

CONCLUSIONS

All 4 MASCs had a large cystic component, including areas of high signal intensity on T₁ weighted images. The solid component appeared as a papillary projection into the cystic component. All 4 AciCCs presented as solid tumours, 2 of which showed high signal intensity on T₁ weighted images.

Intracystic papillary carcinoma of the male breast: a case report

Background

Intracystic papillary carcinoma (IPC) is defined as cancer that develops from the wall of a cyst in the breast. As breast cancer in men accounts for only 1% of all breast cancers, male IPC is an extremely rare form of the disease. The present case report examines IPC in a man, along with an in-depth literature discussion.

Case presentation

A 64-year-old Japanese man noticed a mass in the right breast and sought medical attention. An elastic and soft neoplastic 3-cm lesion was palpated in the right papilla. As a 1-cm solid tumor with a gradual rise from the cyst wall was confirmed within the cyst, vacuum-assisted biopsy (VAB) was performed on that site. Pathological examination of the biopsy revealed heterotypic cells with an enlarged oval nucleus forming dense papillary structures mainly of vascular connective tissue component. Contrast-enhanced computed tomography (CT) confirmed thickening of the wall that protruded outside the cyst. The preoperative diagnosis was right breast cancer (male IPC) TisN0M0 stage 0 luminal B-like. Total mastectomy and sentinel lymph node biopsy were performed. In the excised specimen, a 4.0-cm unilocular cyst was found, along with a 1-cm solid tumor with a gradual rise from the cyst wall. Pathological diagnosis of the resected specimen shared similar characteristics with the solid tumor in the cyst: notably, an oval nucleus with histologically clear nucleolus and fine granular chromatin, cylindrically shaped heterotypic cells, and the presence of basophilic cells in the papillary growth with a thin stem of fibrovasculature as the axis. Some invasion of tumor cells into the interstitium was confirmed. As such, the final diagnosis was right breast cancer (male IPC) T2N0M0 stage IIA luminal B-like. The expression of hormone receptor (ER and PgR) was high, and endocrine therapy was initiated postoperatively (20 mg/day tamoxifen). At the present time (3 months postoperation), there has not been any evidence of metastasis.

Conclusions

We reported a rare case of an IPC in the male breast, along with a literature review.

Impact of avascular areas, as measured by contrast-enhanced harmonic EUS, on the accuracy of FNA for pancreatic adenocarcinoma

BACKGROUND AND AIMS

EUS-guided FNA (EUS-FNA) is used for the diagnosis of pancreatic adenocarcinoma, but sometimes the method results in a false negative. Occasionally, an avascular area may be observed within the pancreatic adenocarcinoma tumor during contrast-enhanced harmonic EUS (CH-EUS). The aim of this study was to evaluate whether the diagnostic sensitivity of EUS-FNA for pancreatic adenocarcinoma was affected by the presence of avascularity on CH-EUS.

METHODS

Two hundred ninety-two patients with pancreatic adenocarcinoma who presented at Kindai University Hospital for EUS-FNA and CH-EUS between June 2009 and August 2013 were retrospectively evaluated. This was a single-center retrospective analysis of prospectively collected data held in a registry. The overall sensitivity of EUS-FNA for the diagnosis of pancreatic adenocarcinoma was calculated. The sensitivities of cytology, histology, and the combination of cytology and histology were also evaluated. These variables were individually evaluated according to the presence or absence of an avascular area on CH-EUS to assess whether the diagnostic sensitivity of EUS-FNA for pancreatic adenocarcinoma was related to the presence of an avascular area within the tumors.

RESULTS

The overall sensitivity of EUS-FNA was 90.8% (265/292). The sensitivities of EUS-FNA for lesions with and without an avascular area were 72.9% (35/48) and 94.3% (230/244), respectively, with the difference being statistically significant (P < .001).

CONCLUSIONS

EUS-FNA has lower sensitivity for pancreatic adenocarcinoma with avascular areas on CH-EUS.

Contrast-enhanced harmonic endoscopic ultrasonography for differential diagnosis of localized gallbladder lesions

BACKGROUND AND AIM

Differential diagnosis of localized gallbladder lesions is challenging. The aim of the present study was to evaluate the utility of contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) for diagnosis of localized gallbladder lesions.

METHODS

One hundred and twenty-five patients with localized gallbladder lesions were evaluated by CH-EUS between March 2007 and February 2014. This was a single-center retrospective study. Utilities of fundamental B-mode EUS (FB-EUS) and CH-EUS in the differentiation of gallbladder lesions and sludge plug were initially compared. Thereafter, these two examinations were compared with respect to their accuracy in the diagnosis of malignant lesions. Five reviewers blinded to the clinicopathological results evaluated microcirculation patterns in the vascular and perfusion images.

RESULTS

In the differentiation between gallbladder lesions and sludge plug, FB-EUS had a sensitivity, specificity, and accuracy of 82%, 100%, and 95%, respectively, whereas CH-EUS had a sensitivity, specificity, and accuracy of 100%, 99%, and 99%, respectively. FB-EUS-based diagnosis of carcinomas based on tumor size and/or shape had a sensitivity, specificity, and accuracy of 61-87%, 71-88%, and 74-86%, respectively. Additional information regarding irregular vessel patterns in the vascular image and/or heterogeneous enhancement in the perfusion image on CH-EUS increased the sensitivity, specificity, and accuracy for the diagnosis of carcinomas to 90%, 98%, and 96%, respectively. There was a significant difference between FB-EUS and CH-EUS in terms of carcinoma diagnosis.

CONCLUSION

CH-EUS was useful for the evaluation of localized gallbladder lesions.

Association between the Risk Factors for Pancreatic Ductal Adenocarcinoma and Those for Malignant Intraductal Papillary Mucinous Neoplasm

BACKGROUND AND AIMS

Risk factors for pancreatic ductal adenocarcinoma (PDAC) include diabetes mellitus, chronic pancreatitis, obesity, a family history of pancreatic cancer, and a history of smoking or alcohol consumption. The aim of this study was to evaluate the association between risk factors for PDAC and malignant intraductal papillary mucinous neoplasm (IPMN).

METHODS

The study included 134 consecutive patients with IPMN who underwent surgical resection at Kindai University Hospital between April 2009 and March 2015. Data on the presence or absence of mural nodules (MNs) and risk factors for PDAC were evaluated. Multivariable logistic regression analysis was performed with malignant IPMN as the outcome variable and MNs and risk factors for PDAC as explanatory variables.

RESULTS

The odds ratio of malignant IPMN to MNs was 3.88 (95% confidence interval [CI] 1.53-9.84; p = 0.004), whereas that of malignant IPMN to smoking history was 1.66 (95% CI 0.74-3.71; p = 0.22). When the presence of MNs was considered as a predictive factor for malignancy, the sensitivity and specificity were 88.5 and 32.1%, respectively, whereas when the presence of both smoking history and MNs was considered, the specificity improved to 73.2%, with a decrease in sensitivity to 42.3%.

CONCLUSIONS

The presence of both a smoking history and MNs was a valuable predictive factor for malignant IPMN with high specificity. A smoking history should be considered before surgical resection in addition to the presence of MNs.

Primary Hepatic Adenosquamous Carcinoma Associated with Primary Sclerosing Cholangitis

INTRODUCTION

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disorder characterized by multiple fibrotic strictures of the bile duct. More than 40% of deaths in PSC patients are related to malignant tumors, including cholangiocarcinoma. Primary hepatic adenosquamous carcinoma (ASC) is a rare subtype of cholangiocarcinoma containing adenocarcinoma (AC) and squamous cell carcinoma (SCC) components, with a poorer prognosis than other cholangiocarcinomas. We report the first case of a hepatic ASC in a patient with PSC.

CASE REPORT

A 28-year-old man was referred for diagnosis and treatment of a liver abscess suspected by contrast-enhanced computed tomography (CE-CT). He had a history of ulcerative colitis and PSC. Abdominal CE-CT revealed a 60-mm-diameter ring-shaped mass with central necrosis in the left lobe. Magnetic resonance imaging demonstrated a poorly circumscribed low-signal-intensity mass in T1-weighted imaging and a high-signal-intensity mass with a scattered low-signal-intensity area in T2-weighted imaging. Abdominal ultrasonography showed a hypoechoic component with a diffuse hyperechoic area in the tumor. Ultrasound-guided biopsy and histological examination showed tumor cells with both squamous and glandular differentiation. Left lobectomy was performed. Microscopic examination revealed 2 components, including moderately differentiated AC and well-differentiated SCC. The final diagnosis was hepatic ASC.

CONCLUSION

This is the first reported case of hepatic ASC in a patient with PSC. Patients with PSC should be recognized as being at a risk of not only general cholangiocarcinoma, hepatocellular carcinoma, and metastatic liver tumor, but also ASC.

Detection of High-Grade Pancreatic Intraepithelial Neoplasia without Morphological Changes of the Main Pancreatic Duct over a Long Period: Importance for Close Follow-Up for Confirmation

Pancreatic intraepithelial neoplasia (PanIN) is a microscopic papillary noninvasive lesion arising from the pancreatic ductal epithelium. However, the natural history and time to progression of high-grade PanIN remain unclear. Herein, we report 2 cases of high-grade PanIN without morphological changes of the main pancreatic duct (MPD) over relatively long periods. In the first case, a 63-year-old man was identified with MPD dilation. Magnetic resonance cholangiopancreatography showed localized stenosis in the pancreatic body with distal MPD dilation. Endoscopic retrograde pancreatography (ERP) was attempted because of possible high-grade PanIN but was unsuccessful. At 15-month follow-up, there was no change in the form of the MPD in various images. However, ERP was re-performed because of possible high-grade PanIN, and cytology showed adenocarcinoma. Postoperative pathology indicated diffuse lesions corresponding to high-grade PanINs in the MPD stenosis and surrounding branches. Final diagnosis was high-grade PanIN. In the second case, a 77-year-old man was identified with MPD dilation. Magnetic resonance cholangiography showed localized stenosis in the MPD of the pancreatic head with distal MPD dilation. He was diagnosed with MPD stenosis caused by chronic pancreatitis, and further examination was not recommended. At 25 months, the patient was referred to our hospital because of a mild change in MPD dilation. ERP showed localized irregular stenosis in the MPD, and cytology showed suspected adenocarcinoma. Postoperative pathology indicated a localized lesion with high-grade PanIN in the branch duct around the MPD stenosis. Final diagnosis was high-grade PanIN. In conclusion, we report 2 cases of high-grade PanIN without morphological changes of the MPD over relatively long periods. Even if a definite diagnosis is not obtained at initial examination, a strict follow-up observational study should be performed. Re-examination, including ERP, should also be considered in cases with risk factors of pancreatic cancer, even if there is no change in MPD form.

Magnifying Narrow Band Imaging (NBI) for the Diagnosis of Localized Colorectal Lesions Using the Japan NBI Expert Team (JNET) Classification

OBJECTIVE

The Japan NBI Expert Team (JNET) proposed a new narrow band imaging (NBI) classification system for colorectal tumors in June 2014. In this classification system, types 1, 2A, 2B, and 3 correspond to hyperplastic polyps (HPs) including sessile serrated polyps (SSPs), low-grade dysplasia (LGD), high-grade dysplasia (HGD) to shallow submucosal invasive (SM-s) carcinomas, and deep submucosal invasive (SM-d) carcinomas, respectively.

METHODS

To validate this system, we performed a retrospective image evaluation study, in which 199 colorectal tumors previously assessed by NBI magnifying endoscopy were classified by 3 blinded experienced colonoscopists using the JNET system. The results were compared with the final pathological diagnoses to determine the JNET classification's accuracy. The interobserver agreement was calculated, and the intraobserver agreement was assessed after 6 months.

RESULTS

The final pathological diagnoses identified 14 HPs/SSPs, 127 LGDs, 22 HGDs, 19 SM-s carcinomas, and 17 SM-d carcinomas. The respective sensitivities, specificities, positive predictive value, negative predictive value, and accuracies were as follows: Type 1, 85.7, 99.5, 92.3, 98.9, and 98.5%; Type 2A, 96.0, 81.9, 90.3, 92.1, and 90.9%; Type 2B, 75.6%, 90.5, 67.3, 93.4, and 87.4%; and Type 3, 29.4%, 100, 100, 93.8, and 94.0%. The interobserver agreement and the intraobserver agreement were moderate (κ value: 0.52) and excellent (κ value: 0.88), respectively. Lesions presenting as Type 2B during NBI comprised a range of colorectal tumors, including HGDs, SM-s, and SM-d.

CONCLUSIONS

The JNET classification was useful for the diagnosis of HPs/SSPs, LGDs, and SM-d, but not SM-s lesions. For low-confidence cases, magnified chromoendoscopy is recommended to ensure correct diagnoses.

Clinical Analysis of Esophageal Stricture in Patients Treated with Intralesional Triamcinolone Injection after Endoscopic Submucosal Dissection for Superficial Esophageal Cancer

INTRODUCTION

Endoscopic submucosal dissection (ESD) has been widely used in the resection of superficial esophageal cancers. Since its use has been extended to cases involving large esophageal tumors occupying nearly the whole or the whole circumference of the lumen, the occurrence of esophageal stricture has increased. Although endoscopic injection of triamcinolone (TA) is widely used for the prevention of postoperative stricture, a significant number of patients still develop stricture after TA injection therapy.

METHODS

We performed a retrospective study to identify the clinical parameters that predispose post-ESD patients to esophageal stricture after TA injection therapy.

RESULTS

A total of 207 patients who were diagnosed with superficial esophageal cancer and subsequently underwent ESD were enrolled in this study. Among these patients, 53 patients and 57 lesions bearing mucosal defects covering greater than two-thirds of the esophageal circumference after ESD were treated with TA injection therapy. The rate of esophageal stricture was found to be highest in cases involving mucosal defects that covered more than seven-eighths of the circumference.

CONCLUSION

Endoscopic TA injection is not sufficient for preventing esophageal stricture in patients bearing mucosal defects covering more than seven-eighths of the esophageal circumference after ESD.

Risk Factors for Postoperative Bleeding in Endoscopic Submucosal Dissection of Colorectal Tumors

BACKGROUND

Colonoscopic removal of adenomatous polyps or early cancer prevents death from colorectal cancer. Endoscopic submucosal dissection (ESD), which enables endoscopists to perform en bloc resection of flat or depressed colorectal tumors >20 mm, has recently been introduced and become a standard procedure in Japan. Although postoperative bleeding (POB) is a major complication associated with ESD, risk factors for POB have not been fully identified.

METHODS

A total of 451 patients (509 lesions) who underwent colorectal ESD were retrospectively analyzed to identify clinical parameters associated with POB.

RESULTS

POB occurred in 14 patients, and 7 of them had received antithrombotic therapy before ESD. Uni- and multivariate analyses revealed that antithrombotic therapy and rectal tumor location were strongly associated with POB following colorectal ESD. The incidence of POB was higher in patients on heparin bridge therapy (HBT) for the replacement of antithrombotic therapy than in patients with no HBT. Four of 7 patients (57.1%) on antithrombotic therapy experienced POB from the rectal lesions.

CONCLUSION

Antithrombotic therapy and rectal lesions result in a higher POB incidence after colorectal ESD.

[A Case of Conversion Surgery for a Patient with Initially Unresectable Pancreatic Cancer with a Pathological Complete Response to S-1 Chemotherapy]

We present a case ofa 67-year-old woman with Stage IV pancreatic head cancer with invasion to the superior mesenteric vein and artery, and distant lymph node metastases. The patient received S-1 mono-chemotherapy. After 2 courses of chemotherapy, the tumor marker was decreased to the normal levels, and the tumor size was dramatically reduced with undetectable lymph node metastases on CT. As the disease status was maintained following chemotherapy, the patient underwent subtotal stomach preserving pancreaticoduodenectomy, 8 months after initiation of the chemotherapy. Histopathologically, no cancer cells were found in the main tumor and dissected lymph nodes. Final diagnosis was made with pathological complete response. The patient was alive without recurrence for 10 months after surgery.

Contrast-enhanced harmonic endoscopic ultrasonography for differential diagnosis of submucosal tumors of the upper gastrointestinal tract

BACKGROUND AND AIM

The study aims to evaluate contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) for the differential diagnosis of submucosal tumors (SMT) of the upper gastrointestinal tract.

METHODS

Between June 2008 and May 2015, 157 consecutive patients with submucosal lesions of the upper gastrointestinal tract were evaluated by CH-EUS. This was a single-center retrospective analysis of prospectively collected data in a registry. The data from 73 patients who later underwent surgical resection were analyzed in this study. Surgical specimens served as the final diagnoses. The two CH-EUS variables of blood flow (hyper-enhancement vs hypo-enhancement) and homogeneity of enhancement pattern were evaluated.

RESULTS

The final diagnoses were 58 gastrointestinal stromal tumors (GISTs) and 15 benign SMTs (two lipomas, five leiomyomas, five schwannomas, two glomus tumors, and one ectopic pancreas). On CH-EUS, 49 of 58 (84.5%) GISTs presented with hyper-enhancement, whereas 4 of 15 (26.7%) benign SMTs showed hyper-enhancement; 21 of 58 (36.2%) GISTs showed inhomogeneous contrast enhancement, while only 2 of 15 (13.3%) benign SMTs demonstrated inhomogeneous contrast enhancement. If hyper-enhancement was considered to indicate GISTs, the sensitivity, specificity, and accuracy were 84.5%, 73.3%, and 82.2%, respectively. If inhomogeneous enhancement was considered to indicate GISTs, the sensitivity, specificity, and accuracy were 36.2%, 86.7%, and 46.6%, respectively. In lesions of less than 2 cm, hyper-enhancement was a more sensitive indicator of GISTs than inhomogeneous enhancement.

CONCLUSIONS

Hyper-enhancement and inhomogeneous enhancement were found to be a characteristic of GISTs. CH-EUS was useful for discrimination of benign SMTs from GISTs.

Kimura's disease affecting the axillary lymph nodes: a case report

Background

Kimura’s disease (KD; eosinophilic granuloma of soft tissue) is an inflammatory granulomatous disorder of unknown cause with eosinophilic infiltration that occurs mainly in soft tissue. KD occurs mainly in the head and neck, but development in the axillary region is very rare.

Case presentation

A 74-year-old Japanese woman was evaluated for a mass that she noted in the left axillary region. On physical examination, there was a palpable, thumb-sized, hard, elastic, freely movable mass in the left axilla. Blood tests showed elevated soluble interleukin-2 receptor (sIL-2R), normal serum immunoglobulin (Ig) G4, and elevated serum IgE. Ultrasonography of the left axilla showed multiple lymph nodes (LNs) with irregular margins in which central hyperechogenicity was lost. A systemic search by computed tomography (CT) showed no systemic lymphadenopathy or other mass-like lesions suspicious for a primary tumour other than in the left axillary LNs. Biopsy of an excised LN was performed under local anaesthesia for a definitive diagnosis. Histopathology showed various-sized lymphoid follicles, large nodular lesions with an enlarged mantle zone, multiple various-sized germinal centres in single nodules, and eosinophilic infiltration between the nodes. Immunohistochemical (IHC) staining of the germinal centres was positive for cluster of differentiation (CD) 10, positive for B-cell lymphoma (bcl)-6, and negative for bcl-2. These findings led to a diagnosis of KD. Ultrasound after 3 months of follow-up showed disappearance of the axillary lymphadenopathy.

Conclusions

A very rare case of KD in the axillary LNs was described. KD has the potential to occur in any region.

Imaging and clinicopathological features of nivolumab-related cholangitis in patients with non-small cell lung cancer

Background Nivolumab demonstrates promising efficacy for the treatment of non-small cell lung cancer and other malignancies. The clinical benefit of nivolumab, however, may be hampered by specific immune-related adverse events (irAEs), and little is known regarding nivolumab-related cholangitis. Methods A computerized search of our clinical database identified 3 metastatic non-small cell lung cancer patients with nivolumab-related cholangitis. All patients were treated with intravenous nivolumab monotherapy (3.0 mg/kg) every 2 weeks until disease progression or irAEs occurred. Clinical data regarding the duration of nivolumab treatment, symptoms, laboratory abnormalities, pathological findings of liver parenchyma biopsy specimens, and management of nivolumab-related cholangitis were analyzed. Results Our analysis revealed that nivolumab-related cholangitis was characterized by (1) localized extrahepatic bile duct dilation without obstruction; (2) diffuse hypertrophy of the extrahepatic bile duct wall; (3) a dominant increase in the biliary tract enzymes alkaline phosphatase and gamma-glutamyl transpeptidase relative to the hepatic enzymes aspartate and alanine aminotransferase; (4) normal or reduced levels of the serum immunological markers antinuclear antibody, antimitochondrial antibody, smooth muscle antibody, and immunoglobulin G4; (5) the pathological finding of biliary tract cluster of differentiation 8-positive T cell infiltration from liver biopsy; and (6) a moderate to poor response to steroid therapy. Conclusions Nivolumab-related cholangitis is associated with distinct imaging and clinicopathological features that distinguish it from acute cholangitis of common etiologies and other immune-related cholangitis. Further studies are warranted to establish the optimal management of patients with this irAE.

Removal of diminutive colorectal polyps: A prospective randomized clinical trial between cold snare polypectomy and hot forceps biopsy

AIM

To compare the efficacy and safety of cold snare polypectomy (CSP) and hot forceps biopsy (HFB) for diminutive colorectal polyps.

METHODS

This prospective, randomized single-center clinical trial included consecutive patients ≥ 20 years of age with diminutive colorectal polyps 3-5 mm from December 2014 to October 2015. The primary outcome measures were en-bloc resection (endoscopic evaluation) and complete resection rates (pathological evaluation). The secondary outcome measures were the immediate bleeding or immediate perforation rate after polypectomy, delayed bleeding or delayed perforation rate after polypectomy, use of clipping for bleeding or perforation, and polyp retrieval rate. Prophylactic clipping after polyp removal wasn’t routinely performed.

RESULTS

Two hundred eight patients were randomized into the CSP (102), HFB (106) and 283 polyps were evaluated (CSP: 148, HFB: 135). The en-bloc resection rate was significantly higher with CSP than with HFB [99.3% (147/148) vs 80.0% (108/135), P < 0.0001]. The complete resection rate was significantly higher with CSP than with HFB [80.4% (119/148) vs 47.4% (64/135), P < 0.0001]. The immediate bleeding rate was similar between the groups [8.6% (13/148) vs 8.1% (11/135), P = 1.000], and endoscopic hemostasis with hemoclips was successful in all cases. No cases of perforation or delayed bleeding occurred. The rate of severe tissue injury to the pathological specimen was higher HFB than CSP [52.6% (71/135) vs 1.3% (2/148), P < 0.0001]. Polyp retrieval failure was encountered CSP (7), HFB (2).

CONCLUSION

CSP is more effective than HFB for resecting diminutive polyps. Further long-term follow-up study is required.

Contrast-enhanced harmonic endoscopic ultrasonography for differential diagnosis of pancreatic cysts

BACKGROUND AND STUDY AIM

Comparison of fundamental B-mode endoscopic ultrasonography (FB-EUS) and contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) in the differential diagnosis of pancreatic cysts according to presence of mural nodules.

PATIENTS AND METHODS

Between April 2007 and April 2012, FB-EUS and CH-EUS data were prospectively collected from 581 consecutive patients with pancreatic cysts, and were retrospectively analyzed from 70 with subsequent cyst resection. Presence and height of mural nodules as detected on FB-EUS and CH-EUS were evaluated, and thence accuracies of both methods for diagnosing mucinous versus nonmucinous and malignant versus benign cysts.

RESULTS

On pathological examination 48 cysts were mucinous and 22 were nonmucinous; 30 cysts were malignant (high grade dysplasia or invasive carcinoma) and 40 were benign. If presence of a mural nodule was considered to indicate a mucinous cyst, FB-EUS and CH-EUS accuracies did not differ significantly (respectively: sensitivity 85 % vs. 79 %; specificity 46 % vs. 96 %; accuracy 73 % vs. 84 %, P = 0.057). If presence of mural nodule was considered to indicate malignancy, CH-EUS was significantly more accurate than FB-EUS (respectively: sensitivity 97 % vs. 97 %; specificity 75 % vs. 40 %; accuracy 84 % vs. 64 %, P = 0.0001). For diagnosing malignancy by evaluating mural nodule height, the area under the receiver operating characteristic (AUROC) was 0.84 and 0.93 for FB-EUS and CH-EUS, respectively (P = 0.028). Presence of a mural nodule of height ≥ 4 mm on CH-EUS was a sign of malignancy (false-positive fraction 0.2; true-positive fraction 0.93; odds ratio 56.0).

CONCLUSIONS

CH-EUS is more accurate than FB-EUS for diagnosing malignant pancreatic cysts.