50-year-old male, presents to the ED describing right sided scalp swelling following a fall. He described a generalised headache, and in ED was noted to be confused with left sided weakness.
His past medical history includes schizophrenia and Hepatitis C.
A CT was performed for suspicion of traumatic head injury.
Describe and interpret the CT scan
Not quite what we were expecting to find on CT.
There is a huge soft tissue density lesion involving the frontal and temporal bones resulting in a calvarial defect.
The lesion has extracranial and intracranial components, with intracranial component causing mass effect and mild compression of the underlying brain parenchyma.
This case shows a huge right sided mass with bony erosion. Initially there was suspicion that this was an invasive meningioma. However, intra-operatively features suggested malignancy.
He underwent stereotactic craniotomy and debulking of the tumour, a 9cm tumour was resected. This was a big procedure that required cranioplastic bone reconstruction, and a flap.
The histopathology revealed metastatic epithelioid tumour, in keeping with either primary hepatocellular or neuroendocrine tumour.
He went on to have CT abdomen
The CT shows a small cirrhotic liver, as well as a lesion in the liver.
Biopsy of the liver lesion confirmed the diagnosis to be Hepatocellular carcinoma (HCC).
HCC is the 5th most common cancer in the world, and the most common liver tumour.
The usual site of metastasis is lung (55%), followed by bone (28%), peritoneum (11%) and adrenal (11%). Brain and skull metastasis are far less common, with brain involvement in only 2% of cases, and carvarial (skull) metastases in 0.5-1.6% of cases.
Calvarial metastases are often asymptomatic and unnoticed. They may become symptomatic due to their mass effect, as in this case.
They may be lytic, sclerotic or mixed lytic-sclerotic in nature. When they cause destruction of the calvarium and extend intracranially, they can directly compress the brain parenchyma resulting in oedema, invasion of major dural venous sinuses and local mass effect on adjacent cranial nerves and vessels.
Sometimes, calvarial metastasis may be the first presenting symptom in a cancer patient, such as this patient. After multidisciplinary input, the patient elected not for further investigation and treatment.
- Kummar S, Shafi NQ. Metastatic hepatocellular carcinoma. Clin Oncol (R Coll Radiol). 2003 Aug;15(5):288-94
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Sydney-based Emergency Physician (MBBS, FACEM) working at Liverpool Hospital. Passionate about education, trainees and travel. Special interests include radiology, orthopaedics and trauma. Creator of the Sydney Emergency XRay interpretation day (SEXI).
Emergency Medicine Education Fellow at Liverpool Hospital NSW. MBBS (Hons) Monash University. Interests in indigenous health and medical education. When not in the emergency department, can most likely be found running up some mountain training for the next ultramarathon.