A 76-year-old man is evaluated for a 1-month history of increasing fatigue, abdominal pain, decreased appetite, and a 4.5-kg (10-lb) weight loss. He does not have cough, dyspnea, or chest pain. Medical history is unremarkable, and he takes no medications. The patient is a lifelong nonsmoker.
On physical examination, the patient is afebrile, blood pressure is 130/80 mm Hg, pulse rate is 84/min, and respiration rate is 12/min. Abdominal examination reveals hepatomegaly. The remainder of the examination is unremarkable.
The serum alkaline phosphatase level is 225 U/L, the serum total bilirubin level is 2.0 mg/dL (34.2 µmol/L), and the serum creatinine level is 0.9 mg/dL (79.6 µmol/L).
Contrast-enhanced CT scans of the abdomen and pelvis show multiple liver metastases with 50% liver replacement and several metastases in the ribs and pelvic bones. CT-guided needle biopsy of the liver reveals high-grade poorly differentiated neuroendocrine cancer. A subsequent chest CT scan shows no evidence of tumor.
Which of the following is the most appropriate treatment?