Presentation
Long standing headache, getting worse after fall in bathroom 2 hours ago. There is also history of left-sided weakness, amnesia, and difficulty in walking for one week, nausea, anorexia, and 5 kg weight loss in the last 2 weeks.
Patient Data
Findings: At least two focal lesions having central hypodensity and isodense walls with extensive surrounding edema are seen in the right posterior parietal lobe. Significant white matter edema without any obvious focal underlying lesion is noted in the right temporal, occipital and both frontal lobes. Minimal left-sided midline shift measuring approximately 4 mm. No skull bone fracture or intracranial hemorrhage is seen.
Impression: Scan findings are suggestive of brain metastases rather than cerebral contusions.
Findings: Average size liver with multiple focal hypodense lesions. These lesions show marked peripheral enhancement on arterial phase of the scan. No obvious internal enhancement is seen in these lesions on any phase of the imaging. No biliary dilatation is seen. Small focal left adrenal gland lesion with attenuation values matching lipid-rich adrenal adenoma. Small bilateral renal cysts.
Impression: Multiple focal hepatic lesions suggestive of hepatic metastases.
Case Discussion
Procedure: Ultrasound-guided biopsy of left hepatic lobe nodule.
Diagnosis: Liver involvement by a poorly differentiated adenocarcinoma.
Immunohistochemistry shows strong positivity of the tumor cells with antibody pancytokeratin (AE1/AE3, CK7 and CK19). The tumor is negative for HMB45, PS100, CK20 and antihepatocytes. The immunostain with antibody CDX2 is focal. This phenotype is suggestive of pancreaticobiliary origin; however, if the tumor is primary in the liver, the diagnosis of intrahepatic cholangiocarcinoma, poorly differentiated should be considered.
Further immunohistochemical study was performed and show positivity of the tumor cells by the antibodies anti-CA 125, anti-TTF-1, anti-CEA and anti-galectin-3, however, these tumor cells do not express PSA, AMACR, CA 19.9, CD10, thyroglobulin and calcitonin. The anti-TTF-1 positivity is usually seen in lung and thyroid, however, some rare cases of cholangiocarcinoma can also be positive.
The patient had a nodule in the left thyroid lobe on ultrasound examination (low-suspicion for malignancy according to the ATA-2015 guidelines). FNAC of this thyroid nodule was done which was negative for malignancy. No other suspicious abnormality was seen on the whole-body CT scan, particularly in the lungs, to suggest the primary source.