Radiology or histopathology: the misdiagnosis of benign and malignant tumors as vascular anomalies.

Background: Benign and malignant soft tissue tumors with a prominent vascular architecture may be misdiagnosed as vascular anomalies on imaging. The aim of this paper is to highlight the limitations of diagnostic imaging and emphasize the importance of histological analysis in obtaining the correct diagnosis.

Methods: We report three cases of non-vascular tumors initially misdiagnosed as vascular malformations despite investigations using a range of imaging modalities including Duplex ultrasound (DUS), computed tomography, magnetic resonance imaging and angiography.

Results: In all three cases, DUS performed in-house demonstrated features suggestive of soft tissue tumors rather than vascular malformations highlighting the operator-dependent nature of DUS. All other imaging modalities including computed-tomography and MR angiography failed to diagnose the lesions correctly. Following biopsy, two patients were diagnosed with malignant tumors, a follicular B-cell lymphoma and an extremely rare plasmacytoid/rhabdoid sarcoma of unknown histogenesis. The third patient had a benign eccrine angiomatous hamartoma (EAH). The patient with the B-cell lymphoma had a history of trauma to the site, causing a delay in diagnosis. There are only a few reports of similar cases documented in the literature.

Conclusions: Diagnostic imaging modalities play an important role in the diagnosis and management of lesions thought to be vascular but as shown in cases presented here, reliance on imaging may result in misdiagnosis. Histological diagnosis of soft tissue lesions should be deemed mandatory where the diagnosis is in doubt.