Chronic liver disease and radiation-induced second primary liver malignancy: a retrospective cohort based on SEER...

Cirrhotic patients are at a high risk of developing radiation-induced liver toxicities despite the modern safe radiation delivery techniques due to the low liver tolerance. Recent studies demonstrated a potential risk of second primary malignancies (SPMs) following radiotherapy (RT) with further investigations for strategies to decrease RT-induced SPMs. However, it is insufficiently addressed if developing liver SPMs is a serious adverse event following RT for cirrhotic patients. Thus, we aimed to quantitatively assess the risk of gastrointestinal (GI) and liver SPMs following RT in patients with liver fibrosis.

The SEER*Stat beta software version 9.0.32 was used to obtain and analyze the data of patients with chronic liver disease diagnosed from 2010 to 2021. We sub-grouped patients according to the history of receiving RT for prior cancer treatment into two groups and excluded patients with unknown RT administration history.

We observed 215 cirrhotic patients developed GI SPMs (O/E = 2.76, P < 0.05, ER = 45.51), 106 of them developed liver SPMs (O/E = 8.80, P < 0.05). Patients with liver cirrhosis who received RT had an increased risk for GI SPMs (Observed = 24, O/E = 3.34, P < 0.05) compared to who received no RT (O/E = 2.71, P < 0.05, ER = 43.72). Liver SPMs after RT in cirrhotic patients had an O/E of 12.31 (Observed = 13, P < 0.05) while the group who received no RT had an O/E of 8.46 (Observed = 93, P < 0.05, ER = 29.77).

Cirrhotic patients who received RT before had an increased risk for GI SPMs by three folds and a 12-fold increased risk for liver SPMs. However, who received no RT had an 8-fold increased risk for liver SPM. Thus, screening for HCC in cirrhotic patients exposed to RT is a must for early detection and better management outcome.