Primary Ewing's sarcoma in a small intestine - a case report and review of the literature

Gastrointestinal Ewing Sarcoma: A Clinicopathological and Molecular Genetic Analysis of 25 Cases

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.

A Practical Approach to Small Round Cell Tumors Involving the Gastrointestinal Tract and Abdomen

Small round cell neoplasms are diagnostically challenging owing to their clinical and pathologic overlap, necessitating use of large immunopanels and molecular analysis. Ewing sarcomas (ES) are the most common, but EWSR1 is translocated in several diverse neoplasms, some with round cell morphology. Molecular advances enable classification of many tumors previously termed 'atypical ES'. The current WHO Classification includes two new undifferentiated round cell sarcomas (with CIC or BCOR alterations), and a group of sarcomas in which EWSR1 partners with non-Ewing family transcription factor genes. This article reviews the spectrum of small round cell sarcomas within the gastrointestinal tract and abdomen.

Distribution and Surgical Management of Visceral Ewing Sarcoma Among Children and Adolescents

INTRODUCTION

Ewing sarcoma (EWS) is a highly malignant tumor of bone and soft tissue that occasionally arises from viscera. Visceral EWS (V-EWS) is challenging to manage given its varied organ distribution and often late-stage presentation. We aimed to characterize our institutional experience with V-EWS, focusing on its surgical management, and to compare V-EWS outcomes against those with osseous (O-EWS) and soft tissue EWS (ST-EWS).

METHODS

Retrospective review of all EWS patients ≤21 years presenting to a single institution between 2000 and 2022. Patient- and disease-specific characteristics were compared. Overall and relapse-free survival were estimated using Kaplan Meier methods and log-rank test.

RESULTS

156 EWS patients were identified: 117 O-EWS, 20 ST-EWS, and 19 V-EWS. V-EWS arose in the kidney (n = 5), lung (n = 5), intestine (n = 2), esophagus (n = 1), liver (n = 1), pancreas (n = 1), adrenal gland (n = 1), vagina (n = 1), brain (n = 1), and spinal cord (n = 1). No significant demographic differences were detected between EWS groups. V-EWS was more frequently metastatic at presentation (63.2%; p = 0.005), yet no significant overall or relapse-free survival differences emerged between EWS groups, with similar follow-up intervals. While V-EWS required multiple unique operative strategies to gain primary control, no significant difference in treatment strategies appeared between groups. Surgery-only primary control was associated with improved overall and relapse-free survival in all groups.

CONCLUSIONS

V-EWS presents unique management challenges in children and adolescents given its variable sites of origin. This large cohort is the first to describe the surgical management and outcomes of V-EWS, demonstrating more frequent metastatic presentation, while achieving similar survival across groups.

LEVEL OF EVIDENCE

Level 2 - Cohort Study.

Ewing's sarcoma of the duodenum: a rare clinical condition managed with surgical resection

A man in his 40s with no medical history presented with right-sided abdominal and chest pain. A CT scan of the abdomen demonstrated a 7.7 cm heterogeneous mass arising from the second part of the duodenum. Oesophagogastroduodenoscopy confirmed a malignant-appearing duodenal lesion, with biopsy showing features consistent with small cell carcinoma. The patient underwent three cycles of neoadjuvant chemotherapy, followed by elective Kausch-Whipple pancreaticoduodenectomy. A combination of immunohistochemistry and molecular studies confirmed the diagnosis of a rare Ewing's sarcoma tumour originating from the duodenum with invasion into the duodenal lumen. The patient recovered well from surgery and remains disease-free 18 months following resection.

Ewing sarcoma of the ileum with wide multiorgan metastases: A case report and review of literature

BACKGROUND

Ewing sarcoma (ES) is an aggressive small round cell tumor that usually occurs in younger children and young adults but rarely in older patients. Its occurrence in elderly individuals is rare. ES of the ileum with wide multiorgan metastases is rarely reported and difficult to distinguish radiologically from other gastrointestinal tract tumors.

CASE SUMMARY

A 53-year-old man presented with right lower quadrant pain for 2 wk. Computed tomography results showed a heterogeneous mass within the ileum and widespread multiorgan metastases. This mass was biopsied, and pathological examination of the resected specimen revealed features consistent with an extraskeletal ES.

CONCLUSION

This case emphasizes the importance of recognizing this rare presentation in the small intestine to broaden the differential diagnosis of adult intraabdominal tumors.

Primary Ewing Sarcoma of Seminal Vesicle on PET/CT

ABSTRACT

Ewing sarcoma is an aggressive malignancy that most often presents as an undifferentiated primary bone tumor; less commonly, it arises in extraosseous soft tissues of mesenchymal cell origin. Primary extraosseous involvement of seminal vesicle is rarely reported. Herein, we describe FDG PET/CT and MRI findings of a 55-year-old man who presented with a pelvic mass, which was confirmed to be primary Ewing sarcoma/primitive neuroectodermal tumor arising from seminal vesicle by histopathologic findings.

Primary Ewing's sarcoma of the small intestine

17 year old female teenager with abdominal pain secondary to pelvic mass of 12 x 10 cm, which seems to depend on ovary. Surgery is scheduled for removal of the tumor, during which it is observed that the lesion originates in the ileum. The histopathological study shows a neoplasm of small round cells with nucleoli and scant cytoplasm. The tumor cells are immunoreactive to CD99 and ERG, being negative for cytokeratins, FLI1, WT1, DOG1 and lymphoid markers. By means of FISH, a rearrangement of the EWSR1 gene was demonstrated. By integrating these molecular and immunohistochemical findings with the morphology, it was diagnosed as Ewing's sarcoma. This aggressive and infrequent tumor originates from neuroectodermal cells and usually develops in the long bones of pediatric and young adult patients, although exceptionally it can occur in other locations. At the intestinal level, it mainly affects the ileum, with a non-specific pain and fatigue clinic. The treatment of choice is surgery for resection of the affected loop, followed by chemotherapy.