Metastatic potential of an aneurysmal bone cyst

Abstract

Aneurysmal bone cysts (ABCs) are benign bone tumors consisting of blood-filled cavities lined by connective tissue septa. Recently, the hypothesis that ABCs are lesions reactive to local hemodynamics has been challenged after the discovery of specific recurrent chromosomal abnormalities. Multiple cases of malignant transformation of ABC into (osteo)sarcoma have been described, as well as a number of cases of telangiectatic osteosarcoma which had been misdiagnosed as ABC. We herewith document a case of a pelvic ABC metastatic to the lung, liver, and kidneys. Diagnosis was confirmed by the presence of a break in the USP6 gene, which is pathognomonic for ABC, in a pulmonary metastasis of our patient. Sarcomatous transformation as an explanation for this behavior was ruled out by demonstrating diploid DNA content in both the pulmonary lesion and the primary tumor.

Computed tomography-guided cementoplasty combined with radiation therapy for an aneurysmal bone cyst in a dog: a case report

“…Aneurysmal bone cysts (ABCs) are expansile osteolytic bone lesions comprised of large vascular sinusoids divided into blood-filled cavities by connective tissue septa that can manifest clinically as non-weight-bearing lameness, pain and swelling (Dowdle et al 2003;Sarierler et al 2004;Van De Luijtgaarden et al 2009). …”

“…In humans, the cysts have been classified as primary or secondary ABCs, occurring with or without a previous coexisting bone lesion, respectively (Feigenberg et al 2001;Van De Luijtgaarden et al 2009). …”

“…Recent studies in humans that reported recurrent chromosomal abnormalities in ABCs have provided a better understanding of the pathogenesis and indicate that primary ABCs are true benign neoplasms (Oliveira et al 2004;Oliveira et al 2006;Van De Luijtgaarden et al 2009;Ye et al 2010). Another study identified the overexpression of insulin-like growth factor-I (IGF-I) as a hallmark of ABCs, indicating a possible role of the IGF-I-system in ABC pathogenesis (Leithner et al 2001).…”

“…Another study identified the overexpression of insulin-like growth factor-I (IGF-I) as a hallmark of ABCs, indicating a possible role of the IGF-I-system in ABC pathogenesis (Leithner et al 2001). ABCs are relatively rare in humans, where they account for only 1% to 2% of primary bone tumours (Feigenberg et al 2001;Van De Luijtgaarden et al 2009). …”

“…Also, malignant transformation has been reported in humans and in a Labrador retriever previously treated with different surgical procedures (Barnhart 2002;Mei et al 2009). ABCs do not usually metastasise (Sarierler et al 2004) but one case of lung, liver and kidney metastasis in a human patient has been described (Van De Luijtgaarden et al 2009). In humans, treatment options include radiotherapy, en bloc resection for expendable bones, curettage, bone graft or bone graft substitute like polymethylmethacrylate (PMMA) filling of the defect, also known as bone cementation.…”