Radiation may augment the antitumoral immune response induced by immunotherapies, such as checkpoint inhibitors approved for treating advanced HCC. (1) We present two cases of HCC with vascular invasion successfully treated with ablative intent yttrium-90 (Y-90) radiation lobectomy (2) in conjunction with nivolumab as a neoadjuvant to resection and liver transplant, resulting in complete pathologic response.

Objective To evaluate the magnitude of humoral response to SARS-CoV-2 mRNA vaccines in cancer patients on active therapies. Patients and Methods Patients ≥ 18 years in whom SARS-CoV-2 spike antibody (anti-S Ab) were measured after 2 doses of SARS-CoV-2 mRNA vaccines were included. Patients with prior COVID-19 infection or on other immunosuppressive therapy were excluded. Results Among 201 patients who met the criteria, 61 were immunocompetent, 91 had a hematologic malignancy, and 49 had a solid malignancy on treatments associated with cytopenia, including chemotherapy or cyclin-dependent kinase 4/6 inhibitors (CDK4/6i). Significantly greater proportion of immunocompetent patients (97%) had anti-S Ab titer ≥ 500 U/mL compared to patients with hematologic (8%) and solid malignancy (55%, p < 0.001). Despite 2 doses of SARS-CoV-2 mRNA vaccines, 53% of hematologic malignancy patients and 8% of solid malignancy patients on cytopenic therapy had no seroconversion (< 0.8 U/mL). Two patients subsequently developed breakthrough COVID-19 infection after full vaccination. Conclusions A substantial proportion of patients with hematologic and solid malignancies on chemotherapies and CDK4/6i had poor humoral responses after SARS-CoV-2 mRNA vaccination. Our study adds to growing body of literature suggesting that immunosuppressed patients have suboptimal humoral response to COVID-19 vaccination. Our study also underscores the significance of assessing antibody response after COVID-19 vaccines in these vulnerable patients.