Chemotherapy is a drug or a combination of drugs that attack cancer cells throughout your body. Your treatment team can use it before or after rectal cancer surgery. At Memorial Sloan Kettering, our medical oncologists use advanced approaches to this kind of personalized medicine. They can customize your chemotherapy treatment based on detailed diagnostic information, such as the genetic features of your rectal tumor. This information can also help refine your plan of care, minimizing side effects as much as possible.
Personalized medicine for rectal cancer treatment
At MSK, patients with metastatic disease have their tumor tissue analyzed by a pathologist to look for specific genetic mutations. Knowing which mutations are there or not can help your medical oncologist determine which chemotherapy drugs will be most effective and minimize side effects.
Some standard chemotherapy drugs aren’t effective in rectal tumors carrying certain mutations. For example, if you have certain mutations in your KRAS, NRAS, or BRAF genes, the drugs panitumumab and cetuximab aren’t good treatment options. Armed with this information, your team would recommend a different drug therapy.
If you have locally advanced rectal cancer, or if the tumor is lying low in the rectum (near the anus), your treatment team may recommend chemotherapy before surgery, also called neoadjuvant therapy. Chemotherapy can help shrink the tumor, making it easier to remove. Chemoradiation, a combination of chemotherapy and radiation, can also help shrink the tumor before surgery.
For other patients we may recommend adjuvant chemotherapy, meaning that the chemotherapy is given after surgery. That’s because some patients develop undetectable microscopic tumor cells that eventually can become new tumors. This approach allows us to clean out any of these microscopic cells after surgery and reduce your risk that the cancer will come back.