Mesohepatectomy for solitary liver metastasis from clear cell renal carcinoma

Clinical History

A 49-year-old patient, submitted to left nephro-adrenalectomy for clear cell renal carcinoma, was being treated with Sunitinib because of a single liver metastasis. Despite the treatment, the lesion increased in dimension and the patient came to our attention for the onset of sub-jaundice, hyperchromic urine and itching.

Imaging Findings

CT confirmed dimensional increase of the hepatic metastasis, located in segments IV and VIII, adjacent to portal and biliary bifurcation (Fig. 1). The right hepatic artery originated from superior mesenteric artery and gave origin to three distal branches for segments VIII, VII and VI (that gave ramifications for segment V), respectively. There was dilatation only of right biliary because of persistence of a thin communication between left biliary duct and common hepatic duct (Fig. 2) that was confirmed also by MRCP (Fig. 3).
A dedicated 3D model was reconstructed that allowed to simultaneously visualise all vascular structures, hepatic parenchyma and metastatic lesion, to simulate surgical resection margins and to obtain the residual parenchymal volume (Fig. 4,5).
On the basis of the favourable location and of vascular anatomy, a central hepatectomy was performed with excision of segments IV and VIII. At operation, the entire tumour was removed with grossly negative margin (Fig. 6).

Discussion

Extensive liver resection or non-anatomic wedge resection is usually recommended as the only curative option for either primary or secondary large or deep-seated liver tumours, but it bears a considerable risk of liver failure because of compromised liver functional reserve. Improvements in the understanding of liver structure, based on functional segmental anatomy, together with advances in imaging technology, have contributed to the development of segment-orientated liver surgery.
Mesohepatectomy is a technique in which the left medial segment and/or right anterior segment of the liver is resected en bloc, preserving the rest of the liver (Fig. 6).
Three-dimensional CT reconstruction of the liver can help identify and map the variations of the intrahepatic vascular structures and their relationship to tumours.
Though less extensive than extended hepatectomies, central liver resections are technically more demanding, since they require more extensive dissection of vascular pedicles and larger transection surfaces.
The question remains whether central hepatectomy or extended hepatectomy is the preferred operative approach for the management of centrally located liver tumours. Postoperative results of patients who undergo mesohepatectomy and extended hepatectomy show that the operative time tends to be longer, the amounts of operative blood loss tends to be greater, and the postoperative hospital stay tends to be shorter in patients who undergo mesohepatectomy, but the differences are not statistically significant. The disease-free survival rates of patients who undergo extended hepatectomy are worse but not statistically different from the mesohepatectomy ones.
In conclusion, mesohepatectomy is technically more complex than typical liver resection but, if performed in reference centres, it is associated with equivalent morbidity and mortality, allowing to save a greater volume of healthy liver parenchyma compared to standard interventions.

Differential Diagnosis List

Final Diagnosis

Single liver metastasis from clear renal cell carcinoma

URL:	https://www.eurorad.org/case/9325
DOI:	10.1594/EURORAD/CASE.9325
ISSN:	1563-4086