Blood Concentrations of Lead, Cadmium, and Mercury Are Associated With Alcohol-Related Liver Disease.

BACKGROUND: An association between environmental pollutants and alcohol-related liver disease (ALD) has not been determined until now. The objectives of this study were to examine the association of the pollutants with ALD, and whether the pollutants together increased the risk of ALD. METHODS: Data were extracted from the Korea National Health and Nutrition Examination Survey (2010-2013 and 2016-2017; n = 11,993). Blood levels of lead, cadmium, and mercury were measured. ALD was defined by a combination of excessive alcohol consumption and ALD/non-alcoholic fatty liver disease index > 0. The aspartate aminotransferase-to-platelet ratio index and fibrosis (FIB)-4 score were used to evaluate ALD FIB. RESULTS: The odds ratios (ORs) of ALD for the highest versus the lowest quartiles of exposure were for lead, 7.39 (95% confidence interval [CI], 5.51-9.91); cadmium, 1.68 (95% CI, 1.32-2.14); and mercury, 5.03 (95% CI, 3.88-6.53). Adjusting for age, gender, smoking, occupation, education, and personal income attenuated the associations but indicated significant positive trends (all Ptrend < 0.001). A positive additive interaction between cadmium and lead was observed. The relative excess OR due to the interaction was 0.96 (95% CI, 0.41-1.51); synergy index = 2.92 (95% CI, 0.97-8.80). Among 951 subjects with ALD, advanced FIB was associated with lead and cadmium (OR, 3.46, 95% CI, 1.84-6.53; OR, 8.50, 95% CI, 2.54-28.42, respectively), but not with mercury. The effect estimates for lead and cadmium remained significant even after adjustment for daily alcohol intake. CONCLUSION: Blood levels of lead, cadmium, and mercury were significantly associated not only with the risk of ALD but also with ALD FIB. Cadmium and lead have synergistic effects that increase the risk of ALD.

The Recent Advances in Molecular Diagnosis of Soft Tissue Tumors.

Soft tissue tumors are rare mesenchymal tumors with divergent differentiation. The diagnosis of soft tissue tumors is challenging for pathologists owing to the diversity of tumor types and histological overlap among the tumor entities. Present-day understanding of the molecular pathogenesis of soft tissue tumors has rapidly increased with the development of molecular genetic techniques (e.g., next-generation sequencing). Additionally, immunohistochemical markers that serve as surrogate markers for recurrent translocations in soft tissue tumors have been developed. This review aims to provide an update on recently described molecular findings and relevant novel immunohistochemical markers in selected soft tissue tumors.

Mediastinal neuroblastoma, ganglioneuroblastoma, and ganglioneuroma: Pathology review and diagnostic approach.

Neuroblastic tumors are a group of tumors of the sympathetic ganglia and adrenal medulla that derive from primordial neural crest cells. These tumors include neuroblastoma, intermixed ganglioneuroblastoma, nodular ganglioneuroblastoma, and ganglioneuroma. Neuroblastomas are the most common extracranial solid tumor arising in childhood and may occur in different anatomic sites. Neuroblastic tumors are common mesenchymal tumors of the mediastinum. Herein, we describe advances in our understanding of neuroblastic tumor biology. Pathologists should be aware of diagnostic challenges associated with these tumors to ensure correct histologic diagnosis and appropriate clinical management. We describe updated mediastinal neuroblastic tumor pathology, focusing on morphological, immunohistochemical, and molecular features and differential diagnoses.

The 2020 WHO Classification of Tumors of Bone: An Updated Review.

Bone tumors are a rare and heterogeneous group of neoplasms that occur in the bone. The diversity and considerable morphologic overlap of bone tumors with other mesenchymal and nonmesenchymal bone lesions can complicate diagnosis. Accurate histologic diagnosis is crucial for appropriate management and prognostication. Since the publication of the fourth edition of the World Health Organization (WHO) classification of tumors of soft tissue and bone in 2013, significant advances have been made in our understanding of bone tumor molecular biology, classification, prognostication, and treatment. Detection of tumor-specific molecular alterations can facilitate the accurate diagnosis of histologically challenging cases. The fifth edition of the 2020 WHO classification of tumors of soft tissue and bone tumors provides an updated classification scheme and essential diagnostic criteria for bone tumors. Herein, we summarize these updates, focusing on major changes in each category of bone tumor, the newly described tumor entities and subtypes of existing tumor types, and newly described molecular and genetic data.

The 2020 WHO Classification of Tumors of Soft Tissue: Selected Changes and New Entities.

Soft tissue tumors are a relatively rare and diagnostically challenging group of neoplasms that can have varying lines of differentiation. Accurate diagnosis is important for appropriate treatment and prognostication. In the 8 years since the publication of the 4th Edition of World Health Organization (WHO) classification of soft tissue tumors, significant advances have been made in our understanding of soft tissue tumor molecular biology and diagnostic criteria. The 5th Edition of the 2020 WHO classification of tumors of soft tissue and bone incorporated these changes. Classification of tumors, in general, but particularly in soft tissue tumors, is increasingly based on the molecular characteristics of tumor types. Understanding tumor molecular genetics improves diagnostic accuracy for tumors that have been difficult to classify on the basis of morphology alone, or that have overlapping morphologic features. In many large hospitals in the United States and Europe, molecular tests on soft tissue tumors are a routine part of diagnosis. Therefore, surgical pathologists should be familiar with newly emerging molecular genetic techniques in clinical settings. In the near future, molecular tests, particularly in soft tissue tumor diagnosis, will become as routine during diagnosis as immunohistochemistry is currently. This new edition provides an updated classification scheme and essential diagnostic criteria for soft tissue tumors. Newly recognized entities and subtypes of existing tumor types, several reclassified tumors, and newly defined molecular and genetic data have been incorporated. Herein, we summarize the updates in the WHO 5th Edition, focusing on major changes in each category of soft tissue tumor, and the newly described tumor entities and subtypes.

Mesenchymal Tumors of the Mediastinum: An Update on Diagnostic Approach.

Mesenchymal tumors of the mediastinum are a heterogenous group of rare tumors with divergent lineages. Mediastinal mesenchymal tumors are diagnostically challenging due to their diversity and morphologic overlap with nonmesenchymal lesions arising in the mediastinum. Accurate histologic diagnosis is critical for appropriate patient management and prognostication. Many mediastinal mesenchymal tumors affect distinct age groups or occur at specific mediastinal compartments. Neurogenic tumors, liposarcoma, solitary fibrous tumor, and synovial sarcoma are common mesenchymal tumors in the mediastinum. Herein, we provide an update on the diagnostic approach to mediastinal mesenchymal tumors and a review of the histologic features and differential diagnosis of common benign and malignant mesenchymal tumors of the mediastinum.

Isolated thoracic intramedullary Erdheim-Chester disease presenting with paraplegia: a case report and literature review.

BACKGROUND: Erdheim-Chester disease (ECD) is a rare, idiopathic, systemic non-Langerhans cell histiocytosis involving long bone and visceral organs. Central nervous system (CNS) involvement is uncommon and most cases develop as a part of systemic disease. We present a rare case of variant ECD as an isolated intramedullary tumor. CASE PRESENTATION: A 75-year-old female patient with a medical history of diabetes and hypertension presented with sudden-onset flaccid paraparesis for 1 day. Neurological examination revealed grade 2-3 weakness in both legs, decreased deep tendon reflex, loss of anal tone, and numbness below T4. Leg weakness deteriorated to G1 before surgery. Preoperative magnetic resonance imaging (MRI) and 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) showed an intramedullary mass lesion at T2-T4 with no systemic lesion, which was heterogeneous enhancement pattern with cord swelling and edema from C7 to T6. Gross total removal was achieved for the white-gray-colored and soft-natured intramedullary mass lesion with an ill-defined boundary. Histological finding revealed benign histiocytic proliferation with foamy histiocytes and uniform nuclei. We concluded it as an isolated intramedullary ECD. The patient showed self-standing and walkable at 18-month with no evidence of recurrence and new lesion on spine MRI and whole-body FDG-PET/CT until sudden occurrence of unknown originated thoracic cord infarction. CONCLUSIONS: We experienced an extremely rare case of isolated intramedullary ECD, which was controlled by surgical resection with no adjuvant therapy. Histological examination is the most important for final diagnosis, and careful serial follow-up after surgical resection is required to identify the recurrence and progression to systemic disease.

Process of Obtaining Social Consensus and 3-Year Functional Outcomes of the First Hand Allotransplantation in Korea.

BACKGROUND: On February 2, 2017, the surgical team of ten board-certified hand specialists of W Hospital in Korea successfully performed the nation's first hand transplantation at Yeungnam University Medical Center (YUMC). This paper reports on the legal, financial, and cultural hurdles that were overcome to open the way for hand transplantation and its functional outcomes at 36 months after the operation. METHODS: W Hospital formed a memorandum of understanding with Daegu city and YUMC to comply with government regulations regarding hand transplantation. Campaigns were initiated in the media to increase public awareness and understanding. With the city's financial and legal support and the university's medical cooperation, a surgical team performed a left distal forearm hand transplantation from a brain-dead 48-year-old man to a 35-year-old left-handed man. RESULTS: With this successful allotransplantation, the Korean Act on Organ Transplantation has now been amended to include hand transplantation. Korean national health insurance has also begun covering hand transplantation. Functional outcome at 36 months after the operation showed satisfactory progress in both motor and sensory functions. The disabilities of the arm, shoulder, and hand score were 23. The final Hand Transplantation Score was 90 points. Functional brain magnetic resonance imaging shows significant cortical reorganization of the corticospinal tract, and reinnervation of intrinsic muscle is observed. CONCLUSIONS: Hand transplantation at the distal forearm shows very satisfactory outcomes in functional, aesthetical, and psychological aspects. Legal and financial barriers against hand transplantation have long been the most burdensome issues. Despite this momentous success, there have been no other clinical applications of vascularized composite allotransplantation due to the limited acceptance by Korean doctors and people. Further public education campaigns for vascularized composite allotransplantation are needed to increase awareness and acceptance.

Paraganglioma in the posterior mediastinum: a case report.

BACKGROUND: Paragangliomas are tumors that arise from extra-adrenal chromaffin cells. Herein, we present a rare case of a functional paraganglioma in the posterior mediastinum. CASE PRESENTATION: A 36-year-old man presented with paroxysms of chest pain and headache. At presentation, the patient's blood pressure was 190/120 mmHg. Chest computed tomography and magnetic resonance imaging revealed a left paravertebral mass in the posterior mediastinum. 123I-metaiodobenzylguanidine scanning revealed focally high tracer uptake in the left paravertebral area. The metanephrine level in the urine was elevated, confirming a rare, catecholamine-producing, functional paraganglioma in the posterior mediastinum. Before surgery, the patient was prepared by orally administering α- and ß-adrenergic blockers. The mass was then resected via a lateral thoracotomy. The metanephrine level in urine was normal 24 h after surgery. CONCLUSIONS: Paragangliomas in the posterior mediastinum are very rare, but more than half of all cases are functional. The associated symptoms are curable with complete resection, and long-term follow-up for recurrence is important.

Giant intradural plexiform schwannoma of the lumbosacral spine - a case report and literature review.

BACKGROUND: Plexiform schwannoma (PS), variant of schwannoma, often involves multiple fascicles as plexiform neurofibroma, and is usually located superficially on the dermis and subcutaneous layers. Spinal PS is extremely rare, and there is insufficient information on its natural course and treatment strategy. We describe the clinical features and treatment of giant intradural PS at the lumbosacral spine. CASE PRESENTATION: A 66-year-old man presented with leg pain, paresthesia, and weakness for 2 years. Magnetic resonance imaging demonstrated a large mass lesion involving a continuous multi-lobulated bead-like mass and a cystic portion from L1 to S3. The lesion was iso-intense on T2-weighted images (WI), iso- to slightly low-intense on T1-WI, and heterogeneous enhancement on contrast-enhanced T1-WI. The large mass lesion had three portions, including a cystic mass at L1, continuous multi-lobulated bead-like mass with a cystic portion from L2 to S1, and multi-lobulated mass from S2 to S3, which were identified with severe adhesions with cauda equina on operative assessment. Grossly total extirpation was achieved at the lumbar spine, and remained three round shaped small masses at the lumbar area and a multi-lobulated round masses from S2 to S3 involving nerves related with motor function of the lower extremities and anal sphincter, respectively. Histological examination revealed multinodular or plexiform growth pattern composed of spindle-shaped tumor cells, which were diffusely and strongly positive for S100 protein with KI67 < 1%. There were no recurrence of preoperative symptoms and changes of the remained masses over a 2-year follow-up period. CONCLUSION: Subtotal extirpation to minimize neural deficits and close observation can be considered an appropriate treatment strategy for a giant spinal PS considering its benign prognosis and histological features, with a high risk of neurological damage during surgery.

Clinicopathologic analysis of intraductal papillary neoplasm of bile duct: Korean multicenter cohort study.

BACKGROUND: IPNB is very rare disease and most previous studies on IPNB were case series with a small number due to low incidence. The aim of this study is to validate previously known clinicopathologic features of intraductal papillary neoplasm of bile duct (IPNB) based on the first largest multicenter cohort. METHODS: Among 587 patients previously diagnosed with IPNB and similar diseases from each center in Korea, 387 were included in this study after central pathologic review. We also reviewed all preoperative image data. RESULTS: Of 387 patients, 176 (45.5%) had invasive carcinoma and 21 (6.0%) lymph node metastasis. The 5-year overall survival was 80.9% for all patients, 88.8% for IPNB with mucosal dysplasia, and 70.5% for IPNB with invasive carcinoma. According to the "Jang & Kim's modified anatomical classification," 265 (68.5%) were intrahepatic, 103 (26.6%) extrahepatic, and 16 (4.1%) diffuse type. Multivariate analysis revealed that tumor invasiveness was a unique predictor for survival analysis. (p = 0.047 [hazard ratio = 2.116, 95% confidence interval 1.010-4.433]). CONCLUSIONS: This is the first Korean multicenter study on IPNB through central pathologic and radiologic review process. Although IPNB showed good long-term prognosis, relatively aggressive features were also found in invasive carcinoma and extrahepatic/diffuse type.

Preischemic transfusion of old packed RBCs exacerbates early-phase warm hepatic ischemia reperfusion injury in rats.

BACKGROUND: Hepatic innate immune cells are considered to play a central role in the early phase of hepatic ischemia reperfusion (IR) injury. Transfusion of old red blood cells (RBCs) is known to prime immune cells, and transfusion before IR may exacerbate liver injury because of the expected hyperresponsiveness of immune cells. MATERIALS AND METHODS: Twenty-four Sprague-Dawley rats were divided into four groups: sham operation (Sham); hepatic IR only (IR Control); and two transfusion groups, preischemic (Pre-T) and postischemic (Post-T), in which allogeneic RBCs stored for 2 weeks were transfused before hepatic IR or after reperfusion, respectively. Partial hepatic ischemia was induced for 90 min, and reperfusion was allowed for 120 min. Serum alanine transaminase levels, area of necrosis, and apoptotic cells were then assessed. Inflammatory (tumor necrosis factor alpha, interleukin 1 beta [IL-1ß], IL-6, IL-10, and cyclooxygenase 2) and oxidative mediators (heme oxygenase 1, superoxide dismutase, and glutathione peroxidase 1) were assessed for elucidating the relevant mechanisms underlying the hepatic injury. RESULTS: Pre-T, but not Post-T, showed increased serum alanine transaminase levels than IR Control (P < 0.05). Area of necrosis was more severe in Pre-T than in IR Control or Post-T (P < 0.01), and apoptotic cells were also more abundant in Pre-T than in IR Control (P < 0.01). tumor necrosis factor alpha and IL-6 levels were higher in Pre-T than in IR Control or Post-T (P < 0.05), with no significant difference in cytoprotective protein levels. CONCLUSIONS: Preischemic transfusion of old RBCs aggravated hepatic injury. Inflammatory cytokines seemed to play a crucial role in liver injury exacerbation. Our results indicate that transfusion before hepatic ischemia may be detrimental.

Predictors of High-Risk Adenoma Occurrence at Surveillance Colonoscopy in Patients Who Undergo Colorectal Adenoma Removal.

OBJECTIVES: Surveillance colonoscopy is recommended after polypectomy because adenoma recurrence is common. The aim of this study was to evaluate the predictors of high-risk adenoma occurrence at surveillance colonoscopy in patients who undergo colorectal adenoma removal and to clarify the association between age and recurrent colorectal adenoma. METHODS: This retrospective study included 563 patients who had colorectal adenomas at baseline colonoscopy and who underwent surveillance colonoscopy. The risk factors for recurrent adenoma were evaluated and the 5-year cumulative incidence rates of overall and high-risk adenoma were compared according to age group. RESULTS: During a mean follow-up period of 3.1 years, 305 (54.2%) patients had overall adenoma recurrence, and 80 (14.2%) patients had high-risk adenoma at surveillance colonoscopy. In a multivariate analysis, old age (≥60 years) and presence of multiple adenomas (3 or more) were significantly associated with high-risk adenoma (p = 0.002 and p = 0.006 respectively). The 5-year cumulative incidence rates of high-risk adenoma were 7.4, 16.7, and 24.1% in the < 50, 50-59, and ≥60 years group respectively (p < 0.001). CONCLUSIONS: Old age (≥60 years) and presence of multiple adenomas (3 or more) were strongly associated with the occurrence of high-risk adenoma at surveillance colonoscopy. The 5-year cumulative incidence of high-grade adenoma was significantly high in the old age group.

Antisenescence effect of mouse embryonic stem cell conditioned medium through a PDGF/FGF pathway.

Cellular senescence, an irreversible state of growth arrest, underlies organismal aging and age-related diseases. Recent evidence suggests that aging intervention based on inhibition of cellular senescence might be a promising strategy for treatment of aging and age-related diseases. Embryonic stem cells (ESCs) and ESC conditioned medium (CM) have been suggested as a desirable source for regenerative medicine. However, effects of ESC-CM on cellular senescence remain to be determined. We found that treatment of senescent human dermal fibroblasts with CM from mouse ESCs (mESCs) decreases senescence phenotypes. We found that platelet-derived growth factor BB in mESC-CM plays a critical role in antisenescence effect of mESC-CM through up-regulation of fibroblast growth factor 2. We confirmed that mESC-CM treatment accelerates the wound-healing process by down-regulating senescence-associated p53 expression in in vivo models. Taken together, our results suggest that mESC-CM has the ability to suppress cellular senescence and maintain proliferative capacity. Therefore, this strategy might emerge as a novel therapeutic strategy for aging and age-related diseases.

Clinicopathological significance of 'subtypes with stem-cell feature' in combined hepatocellular-cholangiocarcinoma.

BACKGROUNDS & AIMS: Combined hepatocellular-cholangiocarcinoma (cHC-CC), a malignant liver tumour with poor prognosis, is composed of hepatocellular carcinoma (HCC), cholangiocarcinoma (CC) and diverse components with intermediate features between HCC and CC, which correspond to hepatic progenitor cells. According to the WHO classification 2010, we surveyed the prevalence and clinicopathological significance of each subtype with stem-cell features [SC subtype; typical subtype (TS), intermediate cell subtype (INT) and cholangiolocellular type (CLC)] in cHC-CC and HCC. METHODS: Sixty-two patients with cHC-CC (19 women and 43 men) and 26 patients with HCC (all men) were examined. The prevalence of each component was histologically assessed with assistance of mucin and immunohistochemical stainings. RESULTS: SC subtypes were observed in all cHC-CCs in various amount and combination. The prevalence of each SC subtype in cHC-CC was as follows: TS, 10 (16.1%); INT, 53 (83.9%) and CLC, 44 (71.0%). The proportion of INT was significantly correlated with gender (female-dominant) (P < 0.05), tumour size (P < 0.05), histological grading of HCC (P < 0.01) and inversely correlated with the degree of stromal fibrosis (P < 0.05). The proportion of CLC was significantly correlated with the degree of fibrosis (P < 0.01) and inflammation (P < 0.01), and inversely correlated with tumour size (P < 0.01) and histological grading of HCC (P < 0.05). The proportion of TS was significantly inversely correlated with the degree of inflammation (P < 0.01). Histological diversity score was significantly correlated with vascular invasion and the positivity for α-foetoprotein. CONCLUSION: The proportion of each SC subtype was significantly associated with certain clinicopathological factors, suggesting different properties of each SC subtypes.

Pituitary blastoma: a pathognomonic feature of germ-line DICER1 mutations.

Individuals harboring germ-line DICER1 mutations are predisposed to a rare cancer syndrome, the DICER1 Syndrome or pleuropulmonary blastoma-familial tumor and dysplasia syndrome [online Mendelian inheritance in man (OMIM) #601200]. In addition, specific somatic mutations in the DICER1 RNase III catalytic domain have been identified in several DICER1-associated tumor types. Pituitary blastoma (PitB) was identified as a distinct entity in 2008, and is a very rare, potentially lethal early childhood tumor of the pituitary gland. Since the discovery by our team of an inherited mutation in DICER1 in a child with PitB in 2011, we have identified 12 additional PitB cases. We aimed to determine the contribution of germ-line and somatic DICER1 mutations to PitB. We hypothesized that PitB is a pathognomonic feature of a germ-line DICER1 mutation and that each PitB will harbor a second somatic mutation in DICER1. Lymphocyte or saliva DNA samples ascertained from ten infants with PitB were screened and nine were found to harbor a heterozygous germ-line DICER1 mutation. We identified additional DICER1 mutations in nine of ten tested PitB tumor samples, eight of which were confirmed to be somatic in origin. Seven of these mutations occurred within the RNase IIIb catalytic domain, a domain essential to the generation of 5p miRNAs from the 5' arm of miRNA-precursors. Germ-line DICER1 mutations are a major contributor to PitB. Second somatic DICER1 "hits" occurring within the RNase IIIb domain also appear to be critical in PitB pathogenesis.

Long-term outcomes after endoscopic ultrasonography-guided gallbladder drainage for acute cholecystitis.

BACKGROUND AND STUDY AIM: Endoscopic ultrasonography-guided transmural gallbladder drainage (EUS-GBD) has been proposed for the management of acute cholecystitis in high risk patients; however, little is known about the long-term outcomes of this treatment. The aim of this study was to evaluate the procedural and long-term outcomes of EUS-GBD with self-expandable metallic stent (SEMS). PATIENTS AND METHODS: Data for this retrospective study were obtained from a prospectively collected EUS database. Patients with acute cholecystitis who were deemed unsuitable for cholecystectomy were included. Study outcomes were technical and clinical success, adverse events, and stent patency. RESULTS: EUS-GBD was technically and clinically successful in 62/63 patients (98.4 %; 95 % confidence interval [CI] 94.9 % - 100 %). Procedural adverse events included duodenal perforation (n = 1, 1.6 %) and self-limiting pneumoperitoneum (n = 2, 3.2 %), all of which resolved with conservative treatment. Long-term outcomes of EUS-GBD were evaluated in 56 patients who were followed for a median of 275 days (range 40 - 1185 days). Late adverse events developed in four patients (7.1 %; 95 %CI 5.7 % - 8.4 %), including asymptomatic distal stent migration (n = 2), and acute cholecystitis due to stent occlusion (n = 2). Two patients with occluded stent were successfully treated endoscopically (reintervention rate of 3.6 %). A total of 54 patients (96.4 %) had no recurrence of acute cholecystitis during follow-up. Median stent patency time was 190 days overall (range 15 - 1185 days) and 458 days (range 151 - 1185 days) for the 28 patients who were alive at the study end. The cumulative stent patency rate was 86 % at 3 years. CONCLUSIONS: EUS-GBD with an SEMS for acute cholecystitis showed excellent long-term outcomes and may be a definitive treatment in patients who are unsuitable for cholecystectomy because of advanced malignancy or high surgical risk.

Microcystic/reticular schwannoma of the esophagus: the first case report and a diagnostic pitfall.

BACKGROUND: Microcystic/reticular schwannoma is a recently described, rare, distinctive histological variant of schwannoma with a predilection for the gastrointestinal tract (GIT). The authors experienced the first case of a microcystic/reticular schwannoma occurring in the esophagus. CASE PRESENTATION: A 39-year-old male presented for an obstructive sensation during swallowing of several months duration. Endoscopy revealed a bulging mass with intact mucosa at 30 cm from incisors in the esophagus. The mass was excised and gross examination showed it was a well circumscribed, unencapsulated nodule, measuring 3.5×3.2×1.2 cm. On microscopic examination, the tumor showed a vague multinodular appearance with a pushing border and tumor cells arranged in a microcystic and reticular growth pattern with anastomosing and intersecting strands of spindle cells in a myxoid or collagenous/hyalinized stroma. Tumor cells showed diffuse nuclear and cytoplasmic positivity for S100. CONCLUSIONS: The authors report the first case of microcystic/reticular schwannoma of the esophagus. Microcystic/reticular schwannoma is a distinctive histological variant of schwannoma with a benign clinical course. However, its histological findings are non-specific and may cause diagnostic difficulties. Awareness of this uncommon neoplasm with distinct histologic features is essential to prevent misdiagnosis.