Hidden in Plain Sight Dr Maryam Mohsin MBCh

Hidden in Plain Sight Dr Maryam Mohsin MBCh. B, MD, FRCR Dr Raneem Albazaz, FRCR, MRCS, BSc, MBCh. B (Hons) St. James’ University Hospital Leeds Teaching Hospital Trust Beckett Street, Harehills Leeds LS 9 7 TF

Background - 67 years old male with genetic haemochromatosis detected on family studies. Subsequent liver biopsy shows only mild fatty change with no histological evidence of iron overload. - 5 cm hepatic haemangioma in segment 7 detected incidentally by ultrasound for deranged LFT in 2015 and confirmed by ultrasound contrast demonstrating initial nodular enhancement, gradual filling in and no washout (Figure 1). New presentation - January 2019 presented with painless visible haematuria. CT Thorax abdomen pelvis was performed and showed 9 cm right renal tumour extending to the renal vein. - Benign hepatic haemangioma was noted again (Figure 2) with no metastatic disease elsewhere. - The patient went for a radical nephrectomy and CT follow up. Follow up - On follow up CT performed July 2020 new change was noted in the internal architecture of the hepatic lesion characterised by small areas of hypodense/cystic change, which in retrospect have been slowly enlarging (Figure 3). - MRI with Primovist was performed and could not characterise the lesion which appeared as moderately hyperintense on T 2 typical for haemangioma with multiple cystic components, extremely vascular, does not washout and does not concentrate Primovist at the hepatobiliary phase of imaging (Figure 4). Given the diagnostic uncertainty the patient went for right posterior hepatic sectionectomy. Diagnosis Final histology: Segment 7 liver multiple foci of metastatic clear cell renal cell carcinoma within a pre-existing haemangioma.

Fig. 1. Ultrasound scan with contrast showing hyper vascular liver lesion. Fig. 3. Follow up Axial CT with contrast showing new cystic change in segment 7 haemangioma. Fig. 2. Axial CT with contrast showing segment 7 haemangioma at time of renal tumour diagnosis Fig. 4. Axial T 2 MRI showing the cystic lesion within the high T 2 haemangioma.