HBV and Cancer Beyond the Liver: What We Know

Chronic hepatitis B virus touches almost 300 million people around the world. It is a top contributor to worldwide cancer numbers, mainly because it can cause liver cancer. New studies are showing that the virus may also be linked to cancers in other parts of the body, such as the stomach, colon, pancreas, lymph nodes and lungs. Researchers have gathered evidence from long‑term studies that people with HBV seem to get these extra cancers more often. However, proving a direct cause is tricky because other factors—like having another virus at the same time, habits such as smoking or diet, and inherited genes—can also raise cancer risk.Scientists believe the virus can jump its DNA into human cells and trigger harmful pathways inside the cell, including PI3K‑Akt and Wnt. A viral protein called HBx can also turn on genes that help tumors grow, change how DNA is packaged (epigenetics), and shift the immune system so cancer cells hide from attack. The good news is that new tools are emerging. Scientists are finding markers in blood and tissues that could signal early cancer changes. Better imaging techniques can spot tumors earlier, and antiviral drugs combined with targeted therapies might improve outcomes for patients whose cancers are linked to HBV. Because the evidence is still debated, doctors and researchers keep studying how exactly HBV increases cancer risk outside the liver. The goal is to develop clearer guidelines for screening, prevention, and treatment, so people living with HBV can get the best care possible.