Safety evaluation of lenvatinib treatment after atezolizumab plus bevacizumab therapy for patients with unresectable liver cancer: A comparison of lenvatinib as 1st‑ or 2nd‑line treatment.

Atezolizumab plus bevacizumab (Atez/BV) as first-line therapy and lenvatinib (LEN) as second-line therapy are the recommended treatments for patients with unresectable hepatocellular carcinoma. Adverse immune events caused by immune checkpoint inhibitors (such as Atez) generally only occur several months after administration; therefore, the potential influence of the first-line treatment on second-line treatment is not clear. The present study investigated the safety of second-line LEN treatment (2nd LEN) by comparing the adverse events (AEs) of 2nd LEN after first-line Atez/BV treatment for unresectable liver cancer, with those of first-line LEN treatment (1st LEN). Patients who received Atez/BV as first-line therapy and 2nd LEN, or those who received 1st LEN at Ogaki Municipal Hospital (Ogaki, Japan) between April 2018 and September 2023 were retrospectively evaluated for treatment duration and AEs. The median treatment duration for patients in the 1st LEN (n=39) and 2nd LEN (n=13) groups was 151.0 days [95% confidence interval (CI) 77-303 days] and 128.5 days (95% CI 68-270 days), respectively (P=0.385). A greater proportion of patients showed elevated aspartate aminotransferase/alanine aminotransferase levels in the 2nd LEN group (76.9%) compared with those in the 1st LEN group (46.2%) (P=0.016). Hypothyroidism was more common in those receiving 2nd LEN (46.2%) than 1st LEN (12.8%) (P=0.016). In addition, grade 1 (three patients) and grade 2 (three patients) hypothyroidism was observed in patients receiving 2nd LEN. For these six patients, during first-line Atez/BV treatment, four patients had grade 0 hypothyroidism and two patients had grade 1 hypothyroidism (P=0.025). In conclusion, patients receiving 2nd LEN after treatment with Atez/BV are at an increased risk of hypothyroidism.