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Shiyanbola O, Nigdelioglu R, Dhall D, González IA, Warmke LM, Schechter S, Choi WT, Hu S, Voltaggio L, Zhang Y, Liang TZ, Ko HM, Charville GW, Longacre TA. Extraskeletal Ewing Sarcoma of the Gastrointestinal and Hepatobiliary Tract: Deceptive Immunophenotype Commonly Leads to Misdiagnosis. Am J Surg Pathol 2024; 48:1185-1194. [PMID: 38767576 PMCID: PMC11321603 DOI: 10.1097/pas.0000000000002236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Ewing sarcoma (ES) is an uncommon mesenchymal neoplasm that typically develops as a bone mass, although up to 30% arise in extraskeletal sites. ES of the gastrointestinal (GI) and hepatobiliary tract is rare and may be misdiagnosed as other, more common neoplasms that occur in these sites. However, the correct classification of extraskeletal ES is important for timely clinical management and prognostication. We reviewed our experience of ES in the GI and hepatobiliary tract in order to further highlight the clinicopathologic features of these neoplasms and document the potential for misdiagnosis in this setting. The archives and consultation files of 6 academic institutions were retrospectively queried for cases of ES occurring in the GI and hepatobiliary tract. The histologic slides and ancillary studies were reviewed and clinical data were retrieved for each case through the electronic medical records, when available. Twenty-three patients with ES in the GI and/or hepatobiliary tract were identified from 2000 to 2022. Of these, 11 were women and 12 were men with a median age of 38 years (range, 2 to 64). Tumor locations included the pancreas (n=5), liver (n=2), stomach (n=3), colorectum (n=3), and small intestine (n=5), as well as tumors involving multiple organs, pelvis and retroperitoneum (n=5). Tumor size varied between 2 cm and 18 cm. Twenty were primary and 3 were metastases. Of the 23 cases, only 17% were initially diagnosed as ES. The most common misdiagnoses involved various forms of neuroendocrine neoplasia due to expression of synaptophysin and other neuroendocrine markers (22%). A wide variety of diagnoses including GI stromal tumor was considered due to aberrant CD117 expression (4%). The diagnosis of ES was ultimately confirmed by detection of the EWSR1 rearrangement in 22 cases. The remaining case was diagnosed using traditional immunohistochemistry. Follow-up information was available in 20 cases, with follow-up time varying between 2 and 256 months. Six patients with follow-up died of disease between 6 and 60 months following initial presentation. Our data indicate ES in the GI and hepatobiliary tract is commonly misdiagnosed leading to a delay in therapy. In light of the attendant therapeutic and prognostic implications, ES should be considered in the differential diagnosis of any GI or hepatobiliary tumor with epithelioid and/or small round cell morphology.
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Affiliation(s)
| | | | - Deepti Dhall
- University of Alabama at Birmingham, Birmingham, AL
| | - Iván A. González
- Department of Pathology and Laboratory Medicine, Indiana University School of Medicine, Indianapolis, IN
| | - Laura M. Warmke
- Department of Pathology and Laboratory Medicine, Indiana University School of Medicine, Indianapolis, IN
| | | | | | | | | | - Yujie Zhang
- Johns Hopkins University School of Medicine, Baltimore, MD
| | - Tom Z. Liang
- Johns Hopkins University School of Medicine, Baltimore, MD
| | - Huaibin M. Ko
- New York-Presbyterian/Columbia University Medical Center, New York City, NY
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Yin T, Shao M, Sun M, Zhao L, Lao IW, Yu L, Wang J. Gastrointestinal Ewing Sarcoma: A Clinicopathological and Molecular Genetic Analysis of 25 Cases. Am J Surg Pathol 2024; 48:275-283. [PMID: 38062799 DOI: 10.1097/pas.0000000000002163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
Occurrence of extraskeletal Ewing sarcoma (ES) in the gastrointestinal (GI) tract is extremely rare. Here, we report 25 cases of ES arising primarily in the GI tract with a focus on the clinicopathological and molecular features, differential diagnosis, and biological behavior. Thirteen patients (52%) were male, and 12 (48%) were female with age ranging from 9 to 59 years (mean: 36.2 years; median: 38 years). Twenty-one tumors (84%) occurred in the small intestine, 3 (12%) in the stomach, and 1 (4%) in the anal canal. At operation, 8/18 (44.4%) patients presented with abdominopelvic disseminated disease. Tumor size measured from 2 to 25 cm (mean: 8.2 cm; median: 6 cm) in maximum size. Microscopically, the tumors were composed of infiltrative small round, ovoid, or short spindle cells arranged mostly in lobular and solid sheet-like patterns with a rich capillary vasculature. Focal formation of Homer Wright-type rosettes and pseudoalveolar architecture was noted each in 2 (8%) cases and 3 (12%) cases. Besides CD99 (25/25; 100%), Fli-1 (15/15, 100%), and NKX2.2 (14/16; 87.5%), the tumor cells also showed variable staining of CD117 (14/17; 82.4%). Of 25 cases, 23 (92%) demonstrated EWSR1 rearrangement by fluorescence in situ hybridization analysis. The 2 cases with negative fluorescence in situ hybridization results were found to harbor EWSR1::ERG and EWSR1::FLI1 fusion by further RNA sequencing, respectively, with a median follow-up of 12 months (range: 1 to 42 months), 5/19 (26.3%) patients developed visceral metastasis and 12/19 (63.2%) patients died of the disease (range:1 to 33 months; median: 9 months). This study showed that GI ES had a predilection for the small intestine, although other sites of the GI tract could also be involved. GI ES had a poor prognosis with a high rate of mortality, particularly in patients with abdominopelvic disseminated disease. In light of appropriate therapeutic strategies and prognostic considerations, it is essential not to misdiagnose GI ES as gastrointestinal stromal tumor owing to the expression of aberrant CD117.
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Affiliation(s)
- Tangchen Yin
- Department of Pathology, Fudan University Shanghai Cancer Center
- Department of Oncology, Shanghai Medical College, Fudan University
- Institute of Pathology, Fudan University, Shanghai, China
| | - Mengyuan Shao
- Department of Pathology, Fudan University Shanghai Cancer Center
- Department of Oncology, Shanghai Medical College, Fudan University
- Institute of Pathology, Fudan University, Shanghai, China
| | - Meng Sun
- Department of Pathology, Fudan University Shanghai Cancer Center
- Department of Oncology, Shanghai Medical College, Fudan University
- Institute of Pathology, Fudan University, Shanghai, China
| | - Lu Zhao
- Department of Pathology, Fudan University Shanghai Cancer Center
- Department of Oncology, Shanghai Medical College, Fudan University
- Institute of Pathology, Fudan University, Shanghai, China
| | - I Weng Lao
- Department of Pathology, Fudan University Shanghai Cancer Center
- Department of Oncology, Shanghai Medical College, Fudan University
- Institute of Pathology, Fudan University, Shanghai, China
| | - Lin Yu
- Department of Pathology, Fudan University Shanghai Cancer Center
- Department of Oncology, Shanghai Medical College, Fudan University
- Institute of Pathology, Fudan University, Shanghai, China
| | - Jian Wang
- Department of Pathology, Fudan University Shanghai Cancer Center
- Department of Oncology, Shanghai Medical College, Fudan University
- Institute of Pathology, Fudan University, Shanghai, China
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Chin X, Cooper S, Martin P. Surgical management of primary gastric Ewing-like sarcoma at the lesser curvature. J Surg Case Rep 2023; 2023:rjad498. [PMID: 37701447 PMCID: PMC10493124 DOI: 10.1093/jscr/rjad498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Accepted: 08/17/2023] [Indexed: 09/14/2023] Open
Abstract
We report the case of a 65-year-old female who presented with a 6-month history of epigastric pain and dyspepsia. Computed tomography of the abdomen and pelvis showed an enhancing nodular lesion and an indeterminate 4 mm lymph node on the lesser curvature of the stomach raising concerns for gastric malignancy. Upper gastrointestinal endoscopy revealed a 10 cm malignant appearing lesion along the gastric lesser curvature. Histopathology demonstrated spindled and small round blue cell tumor with immunohistochemistry staining consistent with Ewing-like sarcoma. After multidisciplinary team discussion the patient was arranged for neoadjuvant chemotherapy with early re-imaging, followed by consideration of gastrectomy. This case highlights the unusual diagnosis of primary gastric Ewing-like sarcoma and the management of this rare condition.
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Affiliation(s)
- Xinlin Chin
- Department of General Surgery, Sunshine Coast University Hospital, Birtinya, Queensland, Australia
- School of Medicine, Griffith University, Birtinya, Queensland, Australia
- College of Medicine & Dentistry, James Cook University, Mackay, Queensland, Australia
| | - Scott Cooper
- Department of General Surgery, Sunshine Coast University Hospital, Birtinya, Queensland, Australia
| | - Priscilla Martin
- Department of General Surgery, Sunshine Coast University Hospital, Birtinya, Queensland, Australia
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Shu Q, Luo JN, Liu XL, Jing M, Mou TG, Xie F. Extraskeletal Ewing sarcoma of the stomach: A rare case report. World J Clin Cases 2023; 11:201-209. [PMID: 36687198 PMCID: PMC9846993 DOI: 10.12998/wjcc.v11.i1.201] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Revised: 11/05/2022] [Accepted: 12/21/2022] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND Extraskeletal Ewing sarcoma (EES) is a rare and highly malignant small round cell tumor associated with a poor clinical outcome. Ewing sarcoma (ES) involving the stomach is an uncommon presentation and can be easily confused with other small round cell tumors. We herein present a rare case of ES involving the gastric area.
CASE SUMMARY We report a case of gastric ES in a 19-year-old female patient who initially presented with a complaint of a tender epigastric mass for 5 d. Contrast-enhanced abdominal computed tomography revealed a soft-tissue-density mass with a diameter of 8.5 cm between the liver and stomach; the mass was connected to the gastric antrum. Then, the mass was surgically excised completely. Upon histopathological, immunophenotype and molecular analysis, the mass was identified to be a primary gastric ES.
CONCLUSION EES is an aggressive tumor with poor prognosis. Therefore, early diagnosis and timely intervention are essential for a good prognosis. It is imperative for us to raise awareness about this rare tumor. Surgical resection is still the best treatment option.
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Affiliation(s)
- Qiang Shu
- Department of Hepatic-Biliary-Pancreatic Surgery, Neijiang First People’s Hospital Affiliated to Chongqing Medical University, Neijiang 641000, Sichuan Province, China
| | - Jia-Nong Luo
- Department of Hepatic-Biliary-Pancreatic Surgery, Neijiang First People’s Hospital Affiliated to Chongqing Medical University, Neijiang 641000, Sichuan Province, China
| | - Xiao-Ling Liu
- Department of Hospital Infection Management, Neijiang Hospital of Traditional Chinese Medicine, Neijiang 641000, Sichuan Province, China
| | - Min Jing
- Department of Pathology, Neijiang First People’s Hospital Affiliated to Chongqing Medical University, Neijiang 641000, Sichuan Province, China
| | - Ting-Gang Mou
- Department of Hepatic-Biliary-Pancreatic Surgery, Neijiang First People’s Hospital Affiliated to Chongqing Medical University, Neijiang 641000, Sichuan Province, China
| | - Fei Xie
- Department of Hepatic-Biliary-Pancreatic Surgery, Neijiang First People’s Hospital Affiliated to Chongqing Medical University, Neijiang 641000, Sichuan Province, China
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Shadhu K, Ramlagun-Mungur D, Ping XC. Ewing sarcoma of the jejunum: A case report and literature review. World J Gastrointest Surg 2021; 13:507-515. [PMID: 34122739 PMCID: PMC8167841 DOI: 10.4240/wjgs.v13.i5.507] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 04/22/2021] [Accepted: 04/29/2021] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Ewing sarcomas (ESs) are highly aggressive malignancy and are predominant in the long bones of extremities of children and young adults with a slight male predilection and rarely presents at extra skeletal locations.
CASE SUMMARY A 55-year-old woman came to our hospital after finding elevated tumor biomarkers during her physical examination. Her enhanced computed tomography scan showed a jejunal mass. The patient underwent laparoscopic enterectomy. The mass was later diagnosed as ES, evidenced by fluorescence in situ hybridization whereby the GLP ES breakpoint region 1 probe was used, showing that more than 10% of the cells showed a red-green-yellow signal proving the breakpoint rearrangement of the ES breakpoint region 1 gene in chromosome 22.
CONCLUSION We describe a case of localized ES at the jejunum in China based on the literature.
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Affiliation(s)
- Kamleshsingh Shadhu
- Department of General Surgery, Gastrointestinal Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu Province, China
- Pre-registration House Officer, Medical Council of Mauritius, Floreal 0000, Plaine Whilhems, Mauritius
| | - Dadhija Ramlagun-Mungur
- Department of General Surgery, Gastrointestinal Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu Province, China
- Pre-registration House Officer, Medical Council of Mauritius, Floreal 0000, Plaine Whilhems, Mauritius
| | - Xiao-Chun Ping
- Department of General Surgery, Gastrointestinal Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu Province, China
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Ye Y, Qiu X, Mei J, He D, Zou A. Primary gastric Ewing sarcoma/primitive neuroectodermal tumor. J Int Med Res 2021; 49:300060520986681. [PMID: 33530793 PMCID: PMC7871060 DOI: 10.1177/0300060520986681] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
A rare and highly malignant small round cell tumor, Ewing sarcoma/primitive neuroectodermal tumor (ES/PNET) usually occurs in the pelvis, long-axis bones, and femur. In contrast, extraosseous ES is more often found in the paraspinal region, limbs, and retroperitoneum, but is extremely rare in the stomach. We report a case of a 55-year-old woman who presented with fatigue, fever, and black stool. Preoperative computed tomography (CT) imaging showed a large ulcerative lesion of approximately 5.5 × 5.0 cm in the stomach and irregular thickening of the ulcer wall. Upper endoscopy revealed a large, irregular ulcer in the posterior wall of the stomach. Histopathological examination suggested that the mass with the largest diameter (7.5 cm) was ES. Immunohistochemistry indicated positivity for CD99. Enhanced CT of the whole body was performed but no definite masses were found in other organs, and the patient was diagnosed with primary gastric ES. The patient underwent radical distal gastrectomy with Roux-en-Y gastrojejunostomy, but refused chemoradiotherapy.
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Affiliation(s)
- Yu Ye
- Department of Radiology, Huangshi Central Hospital, Affiliated Hospital of Hubei Polytechnic University, Edong Health Care Group, Huangshi, Hubei, China.,Department of Dermatology, Huangshi Central Hospital, Affiliated Hospital of Hubei Polytechnic University, Edong Health Care Group, Huangshi, Hubei, China
| | - Xiaoming Qiu
- Department of Radiology, Huangshi Central Hospital, Affiliated Hospital of Hubei Polytechnic University, Edong Health Care Group, Huangshi, Hubei, China.,Department of Dermatology, Huangshi Central Hospital, Affiliated Hospital of Hubei Polytechnic University, Edong Health Care Group, Huangshi, Hubei, China
| | - Jixin Mei
- Department of Radiology, Huangshi Central Hospital, Affiliated Hospital of Hubei Polytechnic University, Edong Health Care Group, Huangshi, Hubei, China.,Department of Dermatology, Huangshi Central Hospital, Affiliated Hospital of Hubei Polytechnic University, Edong Health Care Group, Huangshi, Hubei, China
| | - Dongyun He
- Department of Pediatrics, Shishou People's Hospital, Jingzhou, Hubei, China
| | - Ailing Zou
- Department of Dermatology, Huangshi Central Hospital, Affiliated Hospital of Hubei Polytechnic University, Edong Health Care Group, Huangshi, Hubei, China.,Hubei Key Laboratory of Kidney Disease Pathogenesis and Intervention, Huangshi, Hubei, China
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Bong C, Thomson I, Lampe G. Case report and literature review of Ewing's sarcoma in the gastrointestinal tract. SURGICAL PRACTICE 2018; 22:84-92. [DOI: 10.1111/1744-1633.12292] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Christopher Bong
- Department of Upper Gastrointestinal Surgery and Soft Tissue; Princess Alexandra Hospital; Woolloongabba Queensland Australia
| | - Iain Thomson
- Department of Upper Gastrointestinal Surgery and Soft Tissue; Princess Alexandra Hospital; Woolloongabba Queensland Australia
| | - Guy Lampe
- Department of Anatomical Pathology; Princess Alexandra Hospital; Woolloongabba Queensland Australia
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Li T, Zhang F, Cao Y, Ning S, Bi Y, Xue W, Ren L. Primary Ewing's sarcoma/primitive neuroectodermal tumor of the ileum: case report of a 16-year-old Chinese female and literature review. Diagn Pathol 2017; 12:37. [PMID: 28472972 PMCID: PMC5418692 DOI: 10.1186/s13000-017-0626-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Accepted: 04/17/2017] [Indexed: 12/21/2022] Open
Abstract
Background Ewing’s sarcoma (ES) and primitive neuroectodermal tumors (PNET) are closely related tumors. Although soft tissue ES/PNET are common in clinical practice, they are rare in the small intestine. Because of the absence of characteristic clinical symptoms, they are easily misdiagnosed as other benign or malignant diseases. Case presentation Here, we present the case of a 16-year-old female who complained of anemia and interval hematochezia. Her serum test results showed only a slight elevation of CA-125 and a low level of hemoglobin. Computer tomography and magnetic resonance imaging revealed a cystic and solid mass in the lower abdominal quadrant and pelvic region, which prompted suspicion of a malignant gastrointestinal stromal tumor of the small intestine. After resection, the tumor’s histology and immunohistochemistry (positive for CD99, vimentin and synaptophysin) results suggested ES/PNET. Fluorescent in situ hybridization tests proved the breakpoint rearrangement of the EWSR1 gene in chr 22.Ultrastructural analysis revealed neurosecretory and glycogen granules in the tumor cell cytoplasm. Conclusions Together, these data supported the diagnosis of a rare case of localized ES/PNET in the small intestine without adjuvant chemo- or radiotherapy. To our knowledge, this is the first report from China of a primary small bowel ES/PNET in the English-language literature. In addition, on the basis of findings from previous publications and the current case, the optimal treatment for localized gastrointestinal ES/PNET is discussed.
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Affiliation(s)
- Teng Li
- Department of Pathology, The General Hospital of Air force, PLA, Fucheng Road 30th, Beijing, China
| | - Fang Zhang
- Department of Pathology, The General Hospital of Air force, PLA, Fucheng Road 30th, Beijing, China
| | - Yarui Cao
- Department of Pathology, The General Hospital of Air force, PLA, Fucheng Road 30th, Beijing, China
| | - Shoubin Ning
- Department of Gastroenterology, The General Hospital of Air force, PLA, Fucheng Road 30th, Beijing, China
| | - Yongmin Bi
- Department of Radio and Imaging, The General Hospital of Air force, PLA, Fucheng Road 30th, Beijing, China
| | - Weicheng Xue
- Department of Pathology, Beijing Cancer Hospital, Fucheng Road 52nd, Beijing, China
| | - Li Ren
- Department of Pathology, The General Hospital of Air force, PLA, Fucheng Road 30th, Beijing, China.
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Khuri S, Gilshtein H, Sayidaa S, Bishara B, Kluger Y. Primary Ewing Sarcoma/Primitive Neuroectodermal Tumor of the Stomach. Case Rep Oncol 2016; 9:666-671. [PMID: 27920700 PMCID: PMC5118824 DOI: 10.1159/000449126] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Accepted: 08/15/2016] [Indexed: 01/04/2023] Open
Abstract
Ewing sarcoma/primitive neuroectodermal tumor (ES/PNET) is a tumor of small round cells arising in skeletal tissues. These tumors rarely arise in the stomach. We present a 31-year-old healthy female patient who was admitted to our surgical ward due to upper gastrointestinal hemorrhage. Upper endoscopy revealed a large ulcerated bleeding mass originating from the lesser curvature. Biopsy revealed tumor cell immunoreactivity positive for CD99, vimentin, and Ki67 (an index of proliferation). These findings were compatible with gastric ES/PNET. The fluorescence in situ hybridization analysis result for the EWSR1 gene rearrangement (11: 22 translocation) was positive. The patient refused neoadjuvant treatment and thus underwent an operation during which a mass at the lesser curvature of the stomach was found. The mass was adhering to the pancreatic tail and to the mesentery of the transverse and descending colon. Total gastrectomy, distal pancreatectomy, splenectomy, and left adrenalectomy were done. The patient refused adjuvant treatment. She is free of disease 3 years after surgery.
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Affiliation(s)
- Safi Khuri
- Rambam Health Care Campus, Haifa, Israel
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Song MJ, An S, Lee SS, Kim BS, Kim J. Primitive Neuroectodermal Tumor of the Stomach: A Case Report. Int J Surg Pathol 2016; 24:543-7. [PMID: 27006299 DOI: 10.1177/1066896916639371] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Ewing sarcoma/primitive neuroectodermal tumor (ES/PNET) is a highly aggressive small round cell tumor that mainly occurs in the bone or soft tissue of children or young adults but is extremely rare in the stomach. A 55-year-old man presented with melena and anemia. On endoscopy, an ulcerofungating mass was observed in the high body and total gastrectomy was performed. Histologically, the mass consisted of small round cells with scanty cytoplasm and inconspicuous nucleoli. They often formed perivascular pseudorosettes and multinucleated giant cells were frequently observed. The tumor cells strongly expressed CD99, FLI1, and chromogranin and weakly expressed synaptophysin and CD56. EWS-FLI1 fusion transcript was confirmed by reverse transcription-polymerase chain reaction. ES/PNET is frequently misdiagnosed because of its similarity with small cell carcinoma. Although gastric ES/PNET is very rare, it should be included in differential diagnoses of small round cell tumor in the stomach.
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Affiliation(s)
- Min Jeong Song
- University of Ulsan Collage of Medicine, Asan Medical Center, Seoul, Republic of Korea
| | - Soyeon An
- University of Ulsan Collage of Medicine, Asan Medical Center, Seoul, Republic of Korea
| | - Seung Soo Lee
- University of Ulsan Collage of Medicine, Asan Medical Center, Seoul, Republic of Korea
| | - Beom Su Kim
- University of Ulsan Collage of Medicine, Asan Medical Center, Seoul, Republic of Korea
| | - Jihun Kim
- University of Ulsan Collage of Medicine, Asan Medical Center, Seoul, Republic of Korea
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