The liver rebuilds by expanding its remaining tissue
The liver is the organ that can recover substantial mass after part of it is removed. If a healthy liver is surgically reduced, the portion left behind can grow until it supplies much of the organ’s former capacity. That is why a donor can give part of a liver to someone who needs a transplant, while the donor’s remaining liver grows larger and the transplanted portion grows in the recipient.
The process is not a missing piece growing back in its original shape. Liver cells—especially hepatocytes, the cells that carry out much of the organ’s chemical work—divide in response to signals triggered by the loss of tissue. The remnant enlarges and reorganizes; it does not recreate the exact lobes or outline that were removed.
Regrowth depends on what remains healthy
The often-cited 25% refers to how little liver tissue may be enough to support recovery in favorable circumstances, not a universal safe threshold. The remaining tissue must be healthy and able to meet the body’s needs. Scarring from cirrhosis, severe inflammation, or other damage can limit the liver’s ability to recover, and surgery requires careful assessment of both the donor’s remnant and the recipient’s graft.
This capacity is powerful, but it is not immunity to injury. The liver can restore much of its working mass after a controlled loss; it cannot reliably replace healthy function when the remaining tissue is badly damaged.
