Letter

Salvage Hepatectomy for Giant GIST Liver Metastases Unresponsive to Systemic Therapy-Case Report

Therapeutic decision-making for advanced GIST liver metastases is challenging due to limited clinical evidence. This case study aims to demonstrate the survival benefit of resection in non-responsive cases. A 40-year-old male presented with abdominal pain, weight loss, altered general status, massive hepatomegaly, and intermittent melaena. He was diagnosed with stage IV GIST with the primary tumor in the ileal loop and multiple gigantic synchronous bilobar liver metastases. Despite 31 months of tyrosine-kinase inhibitor therapy post-primary tumor resection, the disease remained unresponsive. The patient was admitted to our tertiary center with significant hepatomegaly. A two-stage debulking liver resection was performed after a multidisciplinary team decision. The first operation debulked the left hemiliver through a non-anatomical ultrasound-guided resection of segments 2, 3, and 4. The second operation (7 weeks later) debulked the right hemiliver through a right posterior sectionectomy involving segments 5 and 8. Despite receiving a second line of tyrosine-kinase inhibitor therapy after surgery, the disease progressed both within and outside the liver. However, the patient survived for 55 months, with a postoperative survival benefit of 25 months. In conclusion, this case emphasizes the significant survival benefit achieved through a complex two-stage debulking liver resection for giant liver metastases, even in cases where systemic therapy fails.

Liver transplantation for hepatobiliary malignancies: a new era of "Transplant Oncology" has begun

The indications of liver transplantation for hepatobiliary malignancies have been carefully expanded in a stepwise fashion, despite the fundamental limitations in oncological, immunological, and technical aspects. A new era of "Transplant Oncology," the fusion of transplant surgery and surgical oncology, has begun, and we stand at the dawn of a paradigm shift in multidisciplinary cancer treatment. For hepatocellular carcinoma, new strategies have been undertaken to select recipients based on biological and dynamic markers instead of conventional morphological and static parameters, opening the doors for a more deliberate expansion of the Milan criteria and locoregional therapies before liver transplantation. Neoadjuvant chemoradiation therapy followed by liver transplantation for unresectable perihilar cholangiocarcinoma developed by the Mayo Clinic provided excellent outcomes in a US multicenter study; however, the surgical indications are not necessarily universal and await international validation. Similarly, an aggressive multidisciplinary approach has been applied for other tumors, including intrahepatic cholangiocarcinoma, hepatoblastoma, liver metastases from colorectal and neuroendocrine primary and gastrointestinal stromal tumors as well as rare tumors, such as hepatic undifferentiated embryonal sarcoma and infantile choriocarcinoma. In conclusion, liver transplantation is an important option for hepatobiliary malignancies; however, prospective studies are urgently needed to ensure the appropriate patient selection, organ allocation and living donation policies, and administration of antineoplastic immunosuppression.

Current status of the organ replacement approach for malignancies and an overture for organ bioengineering and regenerative medicine

Significant achievements in the organ replacement approach for malignancies over the last 2 decades opened new horizons, and the age of "Transplant Oncology" has dawned. The indications of liver transplantation for malignancies have been carefully expanded by a strict patient selection to assure comparable outcomes with non-malignant diseases. Currently, the Milan criteria, gold standard for hepatocellular carcinoma, are being challenged by high-volume centers worldwide. Neoadjuvant chemoradiation therapy and liver transplantation for unresectable hilar cholangiocarcinoma has been successful in specialized institutions. For other primary and metastatic liver tumors, clinical evidence to establish standardized criteria is lacking. Intestinal and multivisceral transplantation is an option for low-grade neoplasms deemed unresectable by conventional surgery. However, the procedure itself is in the adolescent stage. Solid organ transplantation for malignancies inevitably suffers from "triple distress," i.e., oncological, immunological, and technical. Organ bioengineering and regenerative medicine should serve as the "triple threat" therapy and revolutionize "Transplant Oncology."

Liver transplantation for metastasized extragastrointestinal stromal tumor: a case report and an overview of literature

A 63-year-old woman underwent living donor liver transplantation for hepatic metastases of an extragastrointestinal stromal tumor (EGIST) originating from the rectovaginal space. Due to a multifocal extrahepatic tumor recurrence, treatment with imatinib mesylate was started after extensive pharmacokinetic studies to rule out possible interactions with immunosuppressives. We performed several re- resections for EGIST recurrence thereafter. At the last follow-up, 17 years after primary tumor resection and 10 years after living donor liver transplantation, the patient is symptom-free under immunosuppressive and imatinib mesylate treatments with a 2-cm stable recurrent pararectal EGIST. To our knowledge, this is the only report published on a patient who underwent transplantation for hepatic EGIST metastases with a posttransplantation follow-up of 10 years and the first report on living donor liver transplantation for metastasized EGIST. This is the first description of pharmacokinetics of imatinib and its main active metabolite CGP74588 in a liver transplant recipient.