Thanks for posting your query.
with past history of cirrhosis suggests significant decompensated liver with doubtful viral induced rash.
along with significant liver derangement may cause immunosuppression
with predisposition to opportunistic infection
Chemotherapy must be tappered or stop to prevent further progression fresh.
HCC itself is also associated with suppression of immune system.
Your father should also take Immune booster both intravenous and oral preparation.
Dr. Mayank Bhargava