In an analysis of patients with T1 node-positive colon cancer who had previous surgery, adjuvant chemotherapy provided a significant survival advantage, according to a study by Ganapathi et al in Diseases of the Colon and Rectum. However, the investigators noted that a significant minority of this patient population still does not receive adjuvant chemotherapy.
At one time, patients with colon cancer who presented with lymph node metastasis after surgery had a poor prognosis. However, with the advent of adjuvant chemotherapy, particularly oxaliplatin, survival in these patients has increased. Even with this rather successful approach, patients with stage I node-positive disease often do not receive adjuvant chemotherapy. In particular, there is a paucity of outcome data concerning the proportion of patients with stage I node-positive disease.
Therefore, there is a need to look further into how best to manage patients with T1 node-positive colon cancer. Thus, Ganapathi and colleagues aimed to determine treatment trends and the effects of adjuvant chemotherapy on patients with this type of colon cancer.
In total, 36,468 patients with pathologic T1 disease were identified from the National Cancer Database. Of the patients with T1 node-positive disease, further stratification was completed based on whether or not the patient received adjuvant chemotherapy; 70.6% received chemotherapy.
The investigators included only patients with cancer in the cecum, right colon, hepatic flexure, transverse colon, splenic flexure, descending colon, or sigmoid colon to eliminate any lesions that had potential small bowel or rectal involvement. In addition, all patients who died within 30 days of their surgery were excluded from all analyses to avoid bias against the surgery-only group, owing to the inclusion of patients who were never considered for adjuvant therapy.
Higher 5-Year Survival in Those Who Received Chemotherapy
In patients who received chemotherapy for T1 node-positive disease, the 5-year survival rate was 87.9% (median survival = 171.3 months), compared with 63.0% in patients who did not receive chemotherapy (median survival = 92.2 months). Notably, the readmission rate following surgery remained higher in the nonchemotherapy group, and patients receiving chemotherapy were more likely to have a shorter postoperative length of stay as well as a decreased readmission rate.
According to the secondary analysis to identify specific risk factors associated with patients not receiving chemotherapy, only age was a significant risk factor (odds ratio = 2.29 per increasing decade, P < .001).
The results of this study indicate that the use of adjuvant chemotherapy in patients with T1 node-positive colon cancer appears to provide a significant survival advantage. In addition, patients with T1 node-positive disease who receive chemotherapy seem to have an equivalent survival to those with node-negative disease. However, the investigators did note that a significant minority of patients with T1 node-positive disease did not receive adjuvant chemotherapy, even though they should, according to current National Comprehensive Cancer Network Guidelines.
The investigators concluded, “Patients with T1 node-positive colon cancer have a significant survival advantage when adjuvant chemotherapy is used; however, a significant minority of patients still does not receive adjuvant therapy.”
Christopher R. Mantyh, MD, of the Department of Surgery, Duke University Medical Center, Durham, North Carolina, is the corresponding author of this article in Diseases of the Colon and Rectum. The authors reported no financial disclosures.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.