Early Radiation Toxicity from Yttrium-90 Radioembolization for Advanced Hepatocellular Carcinoma

Figure 1. Computed tomography of the chest on axial cuts (left) and sagittal cuts (right) at 10-week follow-up demonstrates central reticular and ground-glass opacities with sparing of both the perihilar and subpleural regions. A 56-year-old man with hepatitis B virus– associated cirrhosis and advanced hepatocellular carcinoma (HCC) presented with dyspnea. He was on therapy with sorafenib and had undergone radioembolization with yttrium 90 (Y) 5 days prior, which was complicated by a high shunt fraction (45%) resulting in an excessive lung radiation exposure of 55 Gy. A technetium-99m macroaggregated albumin (Tc-MAA) scan 1 week prior had demonstrated only a 22% shunt fraction, which would have resulted in a lung radiation dose of less than 30 Gy, the accepted safety standard. Although the initial chest radiograph was normal, given the patient’s symptoms of dyspnea and high dose of radiation exposure, empiric prednisone was prescribed at a dose of 20 mg daily in hopes of preventing radiation pneumonitis (RP). At 1 month follow-up, computed tomography of the chest was normal. Five weeks later, the patient was admitted with worsening dyspnea, and repeat computed tomography demonstrated bilateral ground-glass opacities with sparing of the perihilar regions and periphery (Figure 1). Bronchoscopy with bronchoalveolar lavage and multiple transbronchial biopsies in the affected region were negative for metastatic disease and did not identify any infectious organisms, including Pneumocystis, on special stains and molecular techniques. Histology showed nonspecific inflammation (Figure 2). Sorafenib was discontinued, and the glucocorticoid dose was increased to intravenous methylprednisolone at 60mg daily (equivalent to 1 mg/kg/d) for presumed RP. The patient continued to deteriorate despite therapy, Figure 2. Transbronchial biopsy yielded a 0.43 0.23 0.1–cm sample of alveolar tissue with anthracotic pigment deposition and minor inflammation with no granulomas, malignancy, or microorganisms seen. Cultures were negative (hematoxylin and eosin, 3100).