Younger patients with colorectal cancer have worse prognosis at diagnosis yet better survival, reveals study.
The study was led by Edith Mitchell, M.D., a clinical professor in the Department of Medical Oncology at Jefferson Medical College of Thomas Jefferson University. Dr. Mitchell is also Director of the newly-established Center to Eliminate Cancer Disparities at Jefferson's Kimmel Cancer Center.
"We're seeing more advanced tumors in this population because the cases aren't being caught early enough," said Dr. Mitchell. "Screening isn't recommended until age 50, and the younger a patient is, the more likely they are to ignore symptoms of more advanced stages of the disease."
The objective of this study was to assess pathological features and outcomes of colorectal cancer in patients less than age 50 using an institutional sample and comparing to the Surveillance, Epidemiology and End Results (SEER) database.
Dr. Mitchell and colleagues obtained data from the tumor registry of Thomas Jefferson University Hospital (TJUH) on 4,595 patients treated for colorectal cancer from 1988 to 2007. They compared those data with data obtained from the National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) database on 290,338 patients with colorectal cancer treated from 1988 to 2004. The researchers collected data on location, stage and histologic grade of the cancer.
Patients under age 50 with colorectal cancer presented with more advanced stage tumors in both data sets (SEER and TJUH), and had more poorly differentiated tumors than older patients, the researchers found. Patients under 50 also had more mucinous/signet ring cell tumors with 12 percent to 8.1 percent in the TJUH data and 13.2 percent to 10.3 percent in the SEER data, with younger males having the highest prevalence in both data sets.
Younger patients had fewer right-side tumors than patients 50 and over, and a higher proportion of rectal tumors. Patients under age 50 were also more likely to have positive nodes at all stages relative to 50 and over, as well as more likely to develop peritoneal metastases, but less likely to have lung metastases than older patients.
Despite their poor pathologic features, patients under age 50 had better than or equal survival to those 50 and older, which may in part be explained by their overall health. Early evidence suggests that younger patients are able to tolerate more aggressive cancer therapies because of fewer co-morbidities, said co-author Scott Goldstein, M.D., of Jefferson's Department of Surgery.
"Ongoing studies will help clarify the survival disparity and assess differences in treatment and molecular features between younger and older colorectal cancer patients," Dr. Mitchell said.