SOURCES: George Chang, M.D., associate professor, departments of surgical oncology & health services research, chief, colon and rectal surgery, associate medical director, Colorectal Center, and director, clinical operations, Minimally Invasive and New Technologies in Oncologic Surgery Program, University of Texas MD Anderson Cancer Center, Houston; Ankit Sarin, M.D., assistant professor, surgery, section of colon & rectal surgery, University of California, San Francisco; Jan. 14, 2015, JAMA Surgery, online
WEDNESDAY, Jan. 14, 2015 (HealthDay News) -- Fewer U.S. colon cancer patients who are diagnosed in the final stages of their disease are having what can often be unnecessary surgery to have the primary tumor removed, researchers report.
These patients are also living longer even as the surgery becomes less common, although their general prognosis is not good.
The findings reveal "increased recognition that the first-line treatment really is chemotherapy" for stage 4 colon cancer patients, said study co-author Dr. George Chang, chief of colon and rectal surgery at the University of Texas MD Anderson Cancer Center in Houston. While removing the primary tumor may be helpful for some reasons, he said, "surgery is not life-prolonging."
With the patients in question, their cancer has spread from the intestines to other organs such as the liver or lung, in a process called metastasis. In many cases, the prognosis is death, one expert not part of the study said.
"Cure is not possible for most patients with metastatic colorectal cancer," said Dr. Ankit Sarin, an assistant professor of surgery in the section of colon & rectal surgery at University of California, San Francisco.
Twenty percent of patients diagnosed with colon cancer have stage 4 disease, according to background information in the study. Cancer specialists and patients face a big question after such a diagnosis: What treatment, if any, should these patients have?
"The first instinct is 'I want it out,'" Chang said. But removing the tumor from the colon may not be helpful once cancer has spread, and "getting it out may delay their ability to get treatment that's life-prolonging," Chang added.
In the study, researchers examined a database on more than 64,000 patients diagnosed with stage 4 colon or rectal cancer between 1988 and 2010.
The study reports that about two-thirds of patients underwent removal of the primary tumor, but the procedure became less common over time, dropping from 75 percent of cases in 1988 to 57 percent of cases in 2010.
The study analyzed the "median relative survival rate" of the patients. This is a complicated statistical concept: The American Cancer Society defines relative survival as "the proportion of people with the cancer [who] have survived five years and compares it to the survival expected in a similar group of people without the cancer." The median refers to "the length of time it took for half the people in a certain group... to die."
According to the study, the median relative survival rate for the patients -- those who underwent the surgery and those who didn't -- increased from 9 percent in 1988 to 18 percent in 2009.
Chang added that the median survival time -- not the average -- has risen from fewer than 10 months to two years because of improvements in treatment. The researchers did note that the survival picture may also have brightened because new and better drugs have entered the treatment picture since 1988, including Avastin (bevacizumab), Erbitux (cetuximab) and Xeloda (capecitabine).
In the big picture, the study suggests that the tumor surgery "may still be overused," even though its use has fallen.
What should happen to patients with stage 4 cancer? Sarin, a colon and rectal surgeon, said, "Chemotherapy does not cure metastatic colorectal cancer, but it can improve symptoms and prolong life."
As for surgery, Chang said it may provide some benefit in terms of improving symptoms, but only in certain cases.
Why hasn't surgery become even more uncommon in these patients? "Practices vary considerably in different settings," Sarin said, "and recent research takes time to filter to community hospitals and to non-specialist surgeons."
As for patients who are wondering what to do, Sarin said they need to make sure they're being treated in a way that utilizes treatments like chemotherapy, surgery and radiation as needed "based on the specifics of their cancer and their individual circumstances."
The study is published online Jan. 14 in the journal JAMA Surgery.
For more about colon cancer, try the American Cancer Society.