June 17, 2025
The incidence of early-onset colorectal cancer (EOCRC) in people under age 50 is expected to double between 2023 and 2033. Experts at Mayo Clinic not only recognize the rise in EOCRC but also are taking steps to offer the unique treatment and care this population requires.
"We see a high volume of people with colorectal cancer, and up to 30% of those patients are under age 50," says Michelle F. DeLeon, M.D., a colon and rectal surgeon at Mayo Clinic in Jacksonville, Florida. "Everyone is trying to address the rising incidence of EOCRC, but we are also focusing on how to identify and treat the people who have it."
Diagnosing colorectal cancer under age 50
As with all cases of colorectal cancer (CRC), a precise diagnosis of EOCRC is critical. Dr. DeLeon says every patient diagnosed with CRC undergoes mismatch repair protein testing to screen for hereditary tumors and tumors that may benefit from immunotherapy. After that, the diagnostic process differs for colon and rectal cancers.
"Colon cancer and rectal cancer are two separate disease processes," says Dr. DeLeon. "The pathology and how it looks under a microscope may be the same, but how they behave and how we treat them are very different. Early onset is happening in both organs, but it's increasing at a more rapid rate in rectal cancer."
For both colon and rectal cancers, advanced imaging guides treatment, and minimally invasive diagnostic procedures help prevent unnecessary pain and side effects. The innovative tools Mayo Clinic uses include:
- Endorectal ultrasound.
- Endoscopic submucosal dissection and endoscopic mucosal resection.
- High-resolution MRI.
- Robotic surgery.
- Transanal minimally invasive surgery.
Challenges associated with treating EOCRC
Dr. DeLeon says a multidisciplinary approach to EOCRC is paramount. A tumor board comprising surgeons, pathologists, radiologists, and oncologists discusses all patients diagnosed with colorectal cancer. However, board members understand the challenges and nuances associated with EOCRC.
Cases of EOCRC are more likely to involve:
Treating advanced colorectal cancer
People under 45 who have not been screened for colorectal cancer tend to brush off the early symptoms: abdominal pain, rectal bleeding, diarrhea and iron deficiency anemia. As a result, EOCRC often presents at a later stage, requiring specialized care and surgical expertise. Treating metastatic disease involves collaboration with specialists outside of the colorectal cancer team.
"Our tumor board meets weekly to discuss these cases," says Dr. DeLeon. "But the coordination of care and access to other specialties helps these patients have the best outcomes, especially in patients with more-advanced disease."
For complex cases of EOCRC, Dr. DeLeon says treatment often includes innovative practices, such as:
- Robotic surgery. Better visualization allows surgeons to remove cancer while preserving nearby structures, such as the bladder, prostate, vagina and ovaries.
- Intraoperative radiation therapy. Radiation oncologists deliver radiation at the time of surgery to help decrease recurrence rates.
- Hepatic artery infusion pump (HAIP) chemotherapy. In cases of colorectal liver metastases (CRLM), high doses of chemotherapy are delivered directly to the liver through a pump placed in the hepatic artery.
- Liver transplant. Patients with CRLM may be candidates for a liver transplant, depending on how the tumor responds to chemotherapy.
Preserving fertility
Treating EOCRC poses risks of fertility in both males and females. "As soon as someone is diagnosed with EOCRC, we discuss the fertility risks with them," says Dr. DeLeon. "Then we refer them to the appropriate specialists in case they want to pursue egg retrieval and cryopreservation or sperm banking to address those challenges prior to treatment."
Robotic surgery plays a key role in the effort to prevent scarring around the fallopian tubes and ovaries to help decrease infertility rates. Dr. DeLeon says all female patients with EOCRC receive support from the Women's Health Program before or after surgery.
"Women with EOCRC need extra support — whether they are going into early menopause because of radiation therapy or dealing with sexual dysfunction following surgery, radiation or chemotherapy," she says.
Managing hereditary risk
Up to 30% of EOCRC cases can be attributed to hereditary cancer syndromes, including familial adenomatous polyposis and Lynch syndrome, also called hereditary nonpolyposis colorectal cancer. While still rare, the prevalence is higher than in older adults with CRC.
Having a hereditary cancer syndrome affects the care pathway. "People with hereditary syndromes require strict surveillance, sometimes for several cancer types, including colorectal, endometrial and urothelial cancers," says Dr. DeLeon. "That information also guides treatment. It can be the catalyst for removing the entire colon or rectum for preventive reasons. People with Lynch syndrome are also candidates for immunotherapy."
Mayo Clinic's Early Onset and Hereditary GI Cancers Program has a registry of all patients with CRC related to a hereditary syndrome. Those patients have access to lifelong surveillance and disease management.
Meeting psychosocial needs
People diagnosed with EOCRC require a different type of support than older adults due to the timing of their disease. They often deal with a diagnosis and manage CRC while raising a family or at the height of their career.
"Younger patients tend to undergo different stressors than our older population," says Dr. DeLeon. "We've developed targeted psychosocial programs and make support available to people with EOCRC."
Working to halt the increasing incidence of early-onset colorectal cancer
With cases of EOCRC on the rise, physicians and researchers are trying to address unanswered questions to reduce the occurrence of CRC among younger adults.
"It isn't necessarily about treatment modalities, because we personalize treatment for CRC at every stage and age to make it as effective as possible," says Dr. DeLeon. "But we need to learn why this is happening, how to detect it earlier, and how to prevent it from progressing."
For more information
Refer a patient to Mayo Clinic.