FROM JAMA SURGERY
Adjuvant chemotherapy may be overused among younger patients with colon cancer, without clear evidence of survival benefit over surgery alone, according to a report in JAMA Surgery.
Using data from 3,143 patients with histologically confirmed primary colon adenocarcinoma, in the U.S. Department of Defense’s Central Cancer Registry and Military Heath System medical claims databases, researchers compared overall survival in those who underwent surgery and adjuvant chemotherapy to those who underwent surgery alone.
They found patients aged 18-49 years were up to eight times more likely to receive postoperative systemic chemotherapy across all tumor stages compared to patients aged 65-75 years. The odds ratios ranged from 7.98 for stage I tumors to 2.30 for stage III tumors (JAMA Surgery 2017, Jan 25. doi:10.1001/jamasurg.2016.5050).
“Furthermore, young and middle-aged adults were 2.5 times more likely to receive multiagent chemotherapy regimens and most patients with information on chemotherapy regimens underwent multiagent regimens, suggesting a tendency toward more intense treatments,” wrote Janna Manjelievskaia, MD, of Walter Reed National Military Medical Center, and coauthors.
However, they found that there was no significant difference in survival between those who had surgery and chemotherapy compared to those who had surgery alone, across age groups and tumor stage.
They did note greater overall survival among middle-aged patients with stage I and stage IV disease who were treated with surgery alone, compared to their older counterparts. Younger patients with stage III disease who received surgery alone also had slightly better survival than did older patients.
“The study suggests that more use of chemotherapy in younger patients did not result in additional survival benefits,” the authors wrote.
While national guidelines advise that selected patients with stage II disease – those with inadequately sampled nodes, T3 lesions or poorly differentiated histology – can be considered for adjuvant chemotherapy, the authors argued there is no solid evidence for the effectiveness of chemotherapy in these patients.
“Patients with cancer who receive chemotherapy are vulnerable to its toxicity and adverse effects and may have reduced quality of life,” they wrote. “As a result, patients may undergo decreased physical functional, emotional, and social well-being, although these changes might be mitigated over time.”
Given the additional economic and financial cost of adjuvant chemotherapy, the authors called for further research to evaluate the appropriate use of chemotherapy in colon cancer.
The John P. Murtha Cancer Center, Walter Reed National Military Medical Center, and the National Cancer Institute supported the study. No conflicts of interest were declared.
