Cancer Research Lab

Evaluating a greater number of lymph nodes is associated with increased patient survival after surgical resection of stage II or III colon cancer, according to a report in the March 21st Journal of the National Cancer Institute.

“No minimum [number of nodes] can be determined based on this review, and that number may be elusive and may depend on other factors which are patient- and tumor-related,” Dr. George J. Chang from The University of Texas M. D. Anderson Cancer Center, Houston, Texas “Twelve as proposed, however, seems very achievable in nearly all cases.”

Dr. Chang and colleagues reviewed the evidence on the value of lymph node recovery and evaluation in colon cancer resection.

Two nested cohort studies found an improvement in overall survival among patients with stage II colon cancer as the number of recovered lymph nodes increased, the investigators report.

Among five population/registry-based cohort studies of patients with stage II disease, three showed improved survival with more than 12 lymph nodes evaluated, and two showed that survival increased linearly with the number of lymph nodes evaluated.

All but one of 10 single-institution retrospective cohort studies showed an improvement in overall survival for stage II cancers when greater numbers of lymph nodes were evaluated, the researchers note, but the smallest study showed a difference only in disease-free survival when dividing patients at a cutpoint of 9 lymph nodes.

“All physicians should consider the number of lymph nodes evaluated in the treatment of their patients with colon cancers,” Dr. Chang concluded.

He urged surgeons “to communicate with pathologists if an insufficient number are identified; pathologists to be attentive to communicate with surgeons regarding the specimen delivered to them; medical oncologists to include the number of lymph nodes evaluated when determining indications for adjuvant chemotherapy.”