Why oncologists are calling immunotherapy "revolution" for field of cancer treatment

Nearly 200 million people worldwide are diagnosed with cancer each year. Lung, breast, and colorectal cancers remain the most common types of tumours globally. Yet cancer is no longer an automatic death sentence—many forms can now be treated effectively, including with innovative therapies like CAR-T cell treatment which Oncologists are calling a revolution.

Since 2018, several CAR-T cell therapies have been approved in the EU. They are currently used for specific types of cancer, such as certain leukaemias, lymphomas, and bone marrow tumours. According to Professor Dirk Jäger, Director of the National Center for Tumour Diseases in Heidelberg, who spoke to the German Tagesschau, CAR-T therapy currently addresses only a small portion of cancer cases—but within that group, the impact is transformative.

"I believe CAR-T cells have ushered in a new era in oncology," Jäger says. These genetically modified cells can be both highly effective and extremely precise. “'Genetically modified' sounds negative, but in this case, it's a very positive thing.”

How CAR-T cell therapy works

CAR-T therapy involves genetically altering T cells—part of the body’s immune system—to better detect and destroy cancer cells. In a healthy immune system, T cells identify harmful cells through structures on their surface, acting like a specialized ‘gripper’ that recognizes and binds to targets. When this natural defence fails and cancer forms, scientists can extract T cells from a patient’s blood and reprogram them in the lab. These modified cells develop a new surface structure—known as a chimeric antigen receptor (CAR)—which enables them to specifically detect cancer cells.

After being engineered and multiplied in the lab, the CAR-T cells are reintroduced into the patient via a single infusion. Ideally, these living cells continue circulating in the body, seeking and destroying cancer cells, and in some cases, remain active for years.

Impressive results among children

CAR-T therapy has shown varying success rates depending on the type of cancer. "The most remarkable results are seen in children with treatment-resistant leukaemia," says Jäger. In these cases, CAR-T therapy can cure up to 80% of patients who previously had no other treatment options.

Among adults, however, the success rates are lower but still promising: about half of treated patients experience long-lasting effects. “These are people who would otherwise have died. That’s a major step forward,” Jäger emphasizes.

Despite its promise, CAR-T therapy is not without risks. The immune system can react strongly to the modified cells, sometimes causing severe side effects that require hospitalization for several weeks. As a result, the treatment is currently available only in specialized centers.

There have also been isolated cases in the US where patients developed blood cancer after CAR-T therapy, although it is still unclear whether the therapy caused it. The FDA is monitoring these cases closely. Overall, however, the benefits are believed to outweigh the risks.

Another limitation: the therapy must be tailored for each individual using their own T cells, making the process complex and expensive. A single CAR-T infusion can cost between €200,000 and €380,000. “That sounds like a lot—and it is,” says Jäger. “But if one dose can lead to long-term disease control, it may actually be more cost-effective than long-term chemotherapy.”

Possibilities beyond CAR-T

Currently, CAR-T therapy is only suitable for a limited range of cancers. “For the majority of cancer types, the future role of CAR-T therapy remains uncertain,” Jäger says. Intensive research is ongoing to expand its applicability.

Other forms of T cell–based immunotherapy are also being explored globally. “The possibilities for designing immune responses are vast,” Jäger adds. “We’re going to see a lot of development in this area.”

The most commonly used form of immunotherapy today involves checkpoint inhibitors. These drugs target the immune system’s natural "checkpoints," which prevent it from attacking the body’s own cells. Some tumours exploit these checkpoints to avoid detection by immune cells.

Checkpoint inhibitors can block this process, allowing T cells—often referred to as "killer cells"—to recognize and destroy tumor cells again. “They remove the signal the tumour uses to hide from the immune system,” explains oncologist Carsten Bokemeyer from University Hospital Hamburg-Eppendorf to the publication.

These drugs are already being used successfully for about 15 different types of tumours, including lung, bladder, kidney, breast, and colon cancers. “This approach makes sense for about 25% of all cancer patients today,” says Bokemeyer. It’s been part of oncology practice for about a decade and is sometimes used alongside traditional chemotherapy or on its own.

Checkpoint inhibitors have been especially successful in treating advanced melanoma (black skin cancer). Once difficult to treat after metastasis, this form of cancer has now become a controllable chronic illness for about one-third of patients thanks to this new strategy.

By Nazrin Sadigova