Background: To limit the chimerism typical of transplanted organs, which constantly reveals mixed profiles, laser microdissection (LCM) has been hypothesized as a valid tool in comparison with manual dissection.
Case Report: A 42-year-old man with end-stage HBV/HDV liver cirrhosis and single hepatocellular carcinoma (HCC) underwent liver transplantation. Four months later hepatic nodules were diagnosed. The histological investigation showed an HCC. Despite therapy, the man died as a result of metastatic carcinoma 9 months later.
On behalf of the public prosecutor, we performed short tandem repeat analysis on the hepatic nodules to determine whether the carcinoma had originated from the transplanted liver.
Conclusions: The manually dissected samples revealed a high degree of chimerism that did not allow a clear diagnosis. Instead, the detected chimerism was very low in the microdissected samples, where the tumor origin was clearly diagnosable as a recurrence of the recipient’s primitive HCC. Accordingly, the application of LCM improved the quality of the results leading to an exclusion of medical liability profiles, confirming the high quality safety procedure of the Italian system in solid organ transplantation, and showing at the same time how useful this technique may be in selected forensic cases.

Keywords: recipient’s hepatocarcinoma, transplantation guidelines, laser microdissection, genetic identification, medical liability