Due to the medical advances in chemotherapy and the diverse biological agents available for managing metastatic colorectal cancer, patients are undergoing less tumor removal surgery, according to a study from The University of Texas MD Anderson Cancer Center.
The study, published in the JAMA Surgery journal, showed that there was an increase in overall survival rates in this specific group of patients.
According to the American Cancer Society, in 2014, 136,830 individuals were diagnosed with rectal or colon cancers and from those, 51,260 died as a consequence of the disease. About 20% of all newly diagnosed patients present some level of metastatic disease by the time they are diagnosed, and 80 to 90% of the tumors are considered unresectable.
Study author Professor George Chang, M.D., explained that the main indication for primary tumor resection (PTR) in metastatic cancer is the development of bleeding and obstruction symptoms in these patients. In a very specific group of patients, PTR should be performed to surgically remove primary and metastatic sites. Additionally, Prof. Chang noted that some physicians might be concerned about patients with intact primary tumors developing this symptoms during chemotherapy.
“We know from a previous phase II, cooperative group study that it’s safe to give chemotherapy even with biologics to patients with metastatic disease. Yet there’s still controversy about the role of primary tumor resection because some believe that there’s a survival association. The purpose of our study was to evaluate the use of primary tumor resection among patients with metastatic colorectal cancer in everyday practice and nationally by examining trends in the proportion of metastatic patients undergoing PTR,” Professor Chang said in a news release.
The research team was also interested in understanding and demonstrating that, despite the decreased use of surgery, survival rates were improving. Using the National Cancer Institute’s (NCI) Surveillance, Epidemiology and End Results database, they found that between 1988 and 2010, in the United States, surgery rates decreased from 74.5 to 57.4%, noting that this change was correlated with an increased number of drugs becoming available for chemotherapy. Furthermore, the survival rate of metastatic colon cancer patients improved from 8.6 to 17.8%.
“Our findings tell us that it is increasingly recognized that chemotherapy may be safely given to patients with tumors intact. Although fewer people are getting primary tumors resected, a large proportion of patients with metastatic disease at diagnosis are still having them removed. Together with the observation that primary tumor resection was more likely performed in younger patients who have colon rather than rectal cancers suggests that there may still be an overutilization of PTR and that careful consideration of the indication for such surgery should be made”, Professor Chang added.