肝転移に対する段階的アプローチによる高ビリルビン血症の克服：個別化化学療法に関する症例報告

Hyperbilirubinemia presents a significant challenge in the treatment of patients with hepatic dysfunction, particularly those with metastatic liver disease requiring chemotherapy. Many chemotherapeutic agents undergo hepatic metabolism and elimination, complicating treatment due to altered pharmacokinetics, increased toxicity risks, and the absence of standardized dose adjustments. Patients with severe hepatic impairment are frequently excluded from clinical trials, limiting available evidence on safe and effective treatment strategies for this group of patients. Emerging approaches, including corticosteroids, radiation therapy, and the use of non-hepatically metabolized agents, offer potential avenues for treatment, but clinical data remains limited.

We report a case of a 73-year-old woman diagnosed with a poorly differentiated neuroendocrine carcinoma of unknown primary, presenting with extensive liver metastases and severe hepatic dysfunction. Upon admission, she exhibited significant hyperbilirubinemia (total bilirubin 11.3 mg/dL), precluding the use of standard systemic chemotherapy. A staged therapeutic approach was adopted, beginning with palliative radiation therapy to the liver and corticosteroid administration to reduce hepatic inflammation and improve bile flow. This intervention successfully lowered bilirubin levels to 6.9 mg/dL, enabling the initiation of weekly cisplatin, a renally excreted chemotherapeutic agent. Over time, further reductions in bilirubin permitted the introduction of gemcitabine, albeit at a reduced dose. Despite initial stabilization and a progressive decline in bilirubin, follow-up imaging showed progressive disease with new metastases, ultimately necessitating a transition to palliative care.

This case highlights the potential role of a staged therapeutic strategy in managing severe hyperbilirubinemia in patients with advanced hepatic dysfunction. The use of corticosteroids and liver-directed radiation therapy facilitated chemotherapy initiation in a patient otherwise deemed ineligible for systemic therapy. While the patient ultimately experienced disease progression, this approach underscores the feasibility of individualized interventions to optimize treatment opportunities. This case demonstrates how staged interventions can create a therapeutic window in patients typically ineligible for chemotherapy. While initial bilirubin reduction allowed systemic therapy, disease progressed, highlighting the limits of current approaches and the need for further research into treatment sequencing and supportive strategies, including liver-directed therapies and emerging systemic agents.