Cancer treatment extends well beyond chemotherapy. Depending on the type, location, and genetic profile of a tumor, your oncologist may recommend immunotherapy, targeted therapy, radiation, hormone therapy, stem cell transplants, or several other approaches, either alone or in combination. Many of these options work differently from chemotherapy, attack cancer more precisely, and carry a distinct set of side effects.
Immunotherapy
Immunotherapy works by helping your own immune system recognize and destroy cancer cells. Normally, tumors can hide from immune cells by displaying certain surface proteins that act like a “stand down” signal. Checkpoint inhibitors block those signals, essentially removing the brakes so your T-cells can attack the tumor. These drugs are now used for a wide range of cancers including melanoma, lung cancer, bladder cancer, and kidney cancer.
A more intensive form of immunotherapy called CAR T-cell therapy involves removing your T-cells, genetically engineering them in a lab to recognize a specific protein on your cancer cells, and then infusing them back into your body. The FDA has approved CAR T-cell therapy for several blood cancers, including certain types of lymphoma and leukemia. In 2024, the FDA approved a new use for one CAR T-cell product as the first therapy of its kind for adults with marginal zone lymphoma who have relapsed after two or more prior treatments.
The side effect profile for immunotherapy looks quite different from chemotherapy. Chemotherapy commonly causes bone marrow suppression, hair loss, and drops in blood cell counts. Immunotherapy tends to spare the bone marrow but can cause immune-related problems: the revved-up immune system sometimes attacks healthy tissues, leading to inflammation in the liver, gut, lungs, or skin. In studies comparing the two, severe diarrhea and liver inflammation were among the most notable side effects for immunotherapy patients, while low white blood cell counts and anemia were far more common with chemotherapy.
Targeted Therapy
Where chemotherapy kills rapidly dividing cells without much discrimination, targeted therapy zeroes in on specific molecules that drive a tumor’s growth. Doctors test tumor tissue for particular proteins or gene mutations, then match you with a drug designed to block that exact target. For example, some breast cancers overproduce a protein called HER2 that fuels their growth. A drug specifically designed to bind HER2 can slow or stop those cancer cells while leaving most healthy cells alone.
A similar principle applies in lung and colorectal cancers, where mutations in a growth-signaling protein called EGFR can make tumor cells divide uncontrollably. Drugs that block EGFR interrupt that signal. In chronic myeloid leukemia, a specific gene fusion produces an abnormal protein that drives the cancer. A targeted drug that blocks this protein transformed the disease from a near-certain death sentence into a manageable chronic condition for most patients. These examples illustrate the broader shift: once doctors can identify the molecular flaw powering a cancer, they can often match it with a precisely aimed drug.
Radiation Therapy
Radiation uses high-energy beams to damage the DNA inside cancer cells, preventing them from dividing. It is one of the oldest and most widely used cancer treatments, and modern techniques have made it far more precise than it was even a decade ago.
Intensity-modulated radiation therapy (IMRT) shapes the radiation beam to match the contour of a tumor, reducing damage to surrounding healthy tissue. Stereotactic body radiation therapy (SBRT) delivers very high doses to a small, well-defined target in five or fewer sessions over roughly two weeks, compared to six or seven weeks for conventional radiation. SBRT is commonly used for early-stage lung cancers, liver tumors, and spinal metastases. Internal radiation, called brachytherapy, places a radioactive source directly inside or next to the tumor and is frequently used for cervical and prostate cancers.
Hormone Therapy
Some cancers rely on hormones to grow. Breast cancer cells often need estrogen, and prostate cancer cells typically depend on testosterone. Hormone therapy works by either lowering the body’s production of these hormones or blocking cancer cells from using them.
For breast cancer, this might mean taking a daily pill that blocks estrogen receptors or suppresses estrogen production. For prostate cancer, treatments reduce testosterone levels, sometimes dramatically. Because these cancers are so clearly driven by hormones, anti-hormone therapy is often effective as a first-line treatment or as a long-term strategy after surgery. One limitation is that some tumors eventually develop resistance. Cancer cells can find alternative growth pathways or lose their hormone receptors entirely, which is why hormone therapy is frequently combined with other treatments.
Stem Cell Transplants
Stem cell transplants replace bone marrow that has been destroyed by disease or by the high-dose treatments used to eliminate it. They are most commonly used for blood cancers like leukemia, lymphoma, and multiple myeloma.
There are two main types. An autologous transplant uses your own stem cells, collected and stored before treatment, then returned to your body afterward. An allogeneic transplant uses stem cells from a matched donor. The donor’s immune cells can provide an added benefit: they may recognize and attack remaining cancer cells, a phenomenon called the graft-versus-tumor effect. However, allogeneic transplants carry higher risks because the donor cells can also attack your healthy tissues. The choice between the two depends on the specific cancer, your overall health, and whether a suitable donor is available. Both types are considered standard of care for several blood cancers, according to guidelines from the American Society for Blood and Marrow Transplantation.
Photodynamic Therapy
Photodynamic therapy uses a light-sensitive drug that collects in cancer cells, then activates it with a specific wavelength of light to destroy those cells. Because the light can only penetrate about one-third of an inch of tissue, this approach is limited to cancers on or just beneath the skin, or on the lining of internal organs that can be reached with a light-emitting device during an endoscopy.
The FDA has approved photodynamic therapy for basal cell skin cancer, early-stage squamous cell skin cancer, esophageal cancer, non-small cell lung cancer, and a precancerous condition called Barrett esophagus. It is also used to relieve symptoms when tumors block the throat or airways. It is not a replacement for systemic treatment in advanced cancers, but for the right situations it offers a localized option with minimal impact on surrounding tissue.
How Genomic Testing Guides These Choices
The reason so many non-chemotherapy options now exist is that doctors can analyze the genetic makeup of a tumor in detail. Tumor genomic sequencing looks for mutations, protein overexpression, and other biomarkers that indicate which treatments are most likely to work. This testing can reveal whether a targeted drug is appropriate, whether immunotherapy is a strong candidate, or whether a clinical trial is available for a rare mutation.
In some cases, biomarker testing maps out an entire sequence of treatments: a first-line targeted therapy, a second-line option if the cancer progresses, and then enrollment in a clinical trial if needed. For patients with few standard options remaining, comprehensive testing sometimes uncovers a rare but actionable genetic change that opens the door to a therapy that wouldn’t have been considered otherwise. This approach, broadly called precision medicine, is increasingly the foundation on which treatment decisions are made, and it is the main reason cancer care has moved so far beyond chemotherapy alone.