Experience with hepatectomy in a patient with focal nodular hyperplasia combining with constitutional indocyanine green excretory defect: a case report

This report details the first documented instance of successful hepatic resection performed in a patient presenting with focal nodular hyperplasia (FNH) concomitant with constitutional indocyanine green (ICG) excretory defect - an exceptionally rare hepatic transport disorder initially characterized in 1974. A male patient in his early 20s was diagnosed with FNH necessitating surgical evaluation. Preoperative assessment revealed a profoundly elevated ICG retention rate at 15 min (ICG-R15) of 66.7%, indicating severely impaired clearance based on conventional interpretation. Crucially, however, comprehensive evaluation demonstrated discordantly normal standard liver function biochemical parameters (including bilirubin, transaminases, albumin, coagulation profile) and entirely unremarkable histopathological findings obtained via percutaneous biopsy of radiologically normal liver parenchyma. This definitive constellation of findings confirmed the diagnosis of constitutional ICG excretory defect, effectively excluding intrinsic hepatic parenchymal dysfunction or significant functional impairment. Consequently, proceeding with hepatic mass resection was deemed justified. The surgical intervention and immediate postoperative course were entirely uneventful, characterized by hemodynamic stability, absence of biochemical liver failure, and no complications during the critical recovery phase, with histopathology confirming FNH. This case constitutes a seminal demonstration that ICG clearance kinetics are inherently unreliable and potentially misleading as a sole indicator of functional hepatic reserve in patients harboring this specific excretory defect who are candidates for hepatectomy. Our findings establish the critical principle that the imperative for a multifaceted preoperative evaluation strategy that transcends reliance on ICG kinetics alone to safely guide surgical intervention in this unique patient population.