Metastasis of carcinoid tumor to the transplanted liver graft: a rare case report.

In this study, we present a rare case of gastrointestinal carcinoid tumor that metastasized to a transplanted liver graft. A 14-year-old female patient suffering from cryptogenic cirrhosis had undergone liver transplantation. The liver was received from a deceased donor. She presented to our clinic with complaints of abdominal pain, diarrhea, flushing, fatigue, and syncope four years after transplantation. On multislice computed tomography, multiple masses ranging from 1 cm to 4 cm in size were detected in both lobes of the transplanted liver. Biopsy from both lobes revealed carcinoid tumor. The primary tumor could not be localized, and a colonoscopy was scheduled. As the patient refused an invasive investigation, octreotide therapy was begun. Her symptoms related to the carcinoid tumor diminished following initiation of the octreotide therapy. During the fifth year of octreotide therapy, a whole-body positron emission tomography (PET CT) with 10 mCi F-18 fludeoxyglucose (FDG) showed an increase in the metabolic activity with a SUVmax value of 8 at the localization site, consistent with the ileocecal region. The findings were considered secondary, as the carcinoid tumor originated from the appendix or distal ileum. Again, the patient again refused endoscopic investigations and continued the follow-up visits. To our knowledge, this is the only reported case in the scientific literature of a carcinoid tumor that metastasized to a transplanted liver.