Ewing Sarcoma/Primitive Neuroectodermal Tumor Involving the Duodenum

Area of Science:

• Oncology
• Pathology

Background:

• Ewing sarcoma/primitive neuroectodermal tumor (ES/PNET) is a rare soft tissue malignancy originating from neuroectoderm.
• Extraskeletal ES/PNETs can manifest in diverse locations, with small bowel and mesenteric origins being exceptionally rare.
• Intra-abdominal ES/PNETs often present with nonspecific symptoms, commonly vague abdominal pain.

Observation:

• A 66-year-old female presented with nonspecific symptoms including hypotension, anemia, dyspnea, and coffee-ground emesis.
• Imaging revealed a large, metabolically active mass in the duodenum (10.3 × 8.8 × 12.3 cm).
• Histopathologic diagnosis confirmed the mass as an ES/PNET.

Findings:

• The duodenal mass was successfully treated with chemotherapy followed by radical resection.
• The patient achieved disease-free status 1 year post-treatment.
• This represents the fourth reported case of an ES/PNET involving the duodenum.

Implications:

• ES/PNETs, though rare in the abdomen, should be considered in the differential diagnosis of large soft tissue masses with nonspecific symptoms.
• This case underscores the importance of comprehensive diagnostic workup for unusual presentations of ES/PNET.
• Further research into the early detection and management of intra-abdominal ES/PNETs is warranted.