Two experimental infusions made the detectable signs of metastatic cancer disappear in a three-year-old boy.
The child had hepatoblastoma, a rare tumor that develops in the livers of young children. In his case, the cancer had spread to other parts of the body and resisted chemotherapy. The medical team then turned to an experimental approach based on the patientâs own immune cells.
The principle involves collecting T lymphocytes, cells responsible for defending the body, and then modifying them in the laboratory. They receive an artificial receptor that enables them to recognize a target found on cancer cells. After being reinfused, these so-called CAR-T cells can seek out and attack cells carrying that target.
Here, the chosen target was a protein called GPC3, which is highly present on the surface of many hepatoblastoma cells. The CAR-T cells had also been modified to produce two molecules, interleukins 15 and 21. These act as signals for the immune system and may help the treated cells remain active.
The boy received two infusions. According to the medical team, his cancer subsequently underwent complete regression. No detectable sign of the disease had reappeared at least twelve months after treatment. The result is notable because CAR-T therapies have so far mainly succeeded against certain blood cancers.
Solid tumors, such as those in the liver, are more difficult to reach. Immune cells must penetrate the tumor mass, remain active there, and recognize their targets accurately enough. The environment surrounding the tumor can also hinder their action. Adding the two interleukins may have helped maintain the activity of the cells administered to this child.
However, the significance of the result should be interpreted with great caution. The publication describes the case of a single patient and therefore cannot establish the success rate of this method. The disappearance of the cancer for twelve months is also not enough to confirm that a permanent cure has been achieved.
This case now provides a concrete basis for studying this strategy in more children with hepatoblastoma resistant to standard treatments. Trials involving several patients will need to measure the duration of remissions, side effects, and the exact contribution of the benefit provided by the modified CAR-T cells.