Mesenteric Fibromatosis Mimicking Metastasis of Neuroendocrine Tumor on 18 F-AlF-NOTA-Octreotide PET/CT and Contrast- Enhanced MRI : A Case Report.
Clinicians should be cautious when interpreting imaging results that suggest metastatic disease, as benign conditions can mimic malignancies.
Where it sits
this study against the rest of the octreotide corpusSummary and findings
A 52-year-old man with a history of resected G2 pancreatic neuroendocrine tumor was found to have an abdominal mass during a 17-month follow-up. Imaging suggested metastatic disease, but surgical pathology confirmed mesenteric fibromatosis. The case highlights the diagnostic challenges in distinguishing between benign and malignant lesions.
Abstract
A 52-year-old man with a prior history of resected G2 pancreatic neuroendocrine tumor presented with a newly identified abdominal mass during 17-month follow-up. Contrast-enhanced MRI depicted a heterogeneously hyper-enhancing jejunal mesenteric lesion, highly suggestive of metastatic disease. ¹⁸F-AlF-NOTA-Octreotide PET/CT revealed mild tracer accumulation within the lesion, which was initially interpreted as NET metastasis. Surgical pathology ultimately confirmed mesenteric fibromatosis. This case emphasizes an important diagnostic trap, as benign fibromatosis can mimic NET metastasis on both anatomic and SSTR-targeted PET imaging, alerting clinicians to avoid misdiagnosis and unnecessary treatment.
Background
This paper addresses the diagnostic challenges in differentiating mesenteric fibromatosis from metastatic neuroendocrine tumors (NETs) using imaging techniques. Previous knowledge indicates that imaging can sometimes mislead clinicians, leading to unnecessary treatments. This case is significant as it highlights the potential for benign conditions to mimic malignancies on imaging studies.
Methods
Not reported in abstract.
Results
Not reported in abstract.
Interpretation
The findings suggest that while imaging can indicate the presence of metastatic disease, it is crucial to confirm with surgical pathology, as benign conditions like fibromatosis can present similarly. This case adds to the literature by emphasizing the importance of accurate diagnosis to prevent overtreatment. The effect size of the imaging findings is not clinically meaningful without confirmation from pathology.
Key findings
- 17-month follow-up after resection of G2 pancreatic neuroendocrine tumor.
- Mild tracer accumulation within the lesion on ¹⁸F-AlF-NOTA-Octreotide PET/CT.
- Surgical pathology confirmed mesenteric fibromatosis, not metastatic disease.
Limitations
- Not a controlled study.
- Single case report limits generalizability.
- No quantitative data on imaging findings.