Multiple Intraosseous Calvarial Hemangiomas Mimicking Metastasis from Renal Cell Carcinoma

Abstract

Renal cell carcinomas are known to metastasise to the bones in the form of lytic lesions. However, not all osteolytic lesions in patients with renal cell carcinoma are metastatic in nature. The report describes the case of a 68-year old lady who was diagnosed with a renal cell carcinoma 3 and half years back and treated with radical nephrectomy along with excision of an inferior vena cava tumour thrombus. The tumour was completely excised and she remained disease free till date. Subsequently, multiple lytic lesions were detected incidentally on the cranial vault, which on biopsy demonstrated intraosseous hemangioma. Though it is well known that renal cell carcinomas can metastasise to the bones in the form lytic lesions, it is important for clinicians to remember a few other differentials, one of which would be an intraosseous hemangioma, which is a benign pathology. Many times patients would be treated as having metastatic disease merely on radiological findings. In this case report, there was a high index of radiological suspicion for metastases, however establishing diagnosis by biopsy prevented overtreatment in this instance.

A unique case of multiple calvarial hemangiomas with one large symplastic hemangioma

“…Hemangiomas malignant degeneration has not been reported so far [ 17 , 18 ]. Histologically, hemangiomas are classified according to the predominant type of vascular channel into four variants, cavernous, capillary, arteriovenous, and venous, and these variants are known to coexist [ 5 , 19 ]. The cavernous type is predominant in hemangiomas of the skull [ 20 ].…”

“…Approximately 13% of calvarial lesions are hemangiomas, they are slow-growing, and benign. The majority of cases have been reported to contain a single lesion; however, the incidence of multifocal hemangiomas of the skull appears to be extremely rare [ 5 – 8 ]. They are usually asymptomatic, but may become symptomatic if they are large enough, with a compressing effect.…”

Solitary benign parietal lesions seen on CT in cancer patients

“…They are three times more common in females than males [17] . Hemangiomas are slow growing, painless and malignant transformation is unknown [17] .…”

“…They are three times more common in females than males [17] . Hemangiomas are slow growing, painless and malignant transformation is unknown [17] . The parietal bone is most commonly affected followed by the frontal bone [12] .…”

“…There are two types of hemangiomas: traumatic and congenital [12] . Mostly, skull hemangiomas are asymptomatic, require no treatment, and have no significant sequelae [17] . On CT, they can assume the heterogeneous sunburst or honeycomb pattern [18] .…”