Deng, Y. et al. High epidermal growth factor receptor expression in metastatic colorectal cancer lymph nodes may be more prognostic of poor survival than in primary tumor. Am. J. Clin. Oncol. 32, 245–252 (2009).

Patients with metastatic colorectal cancer have poor survival rates. Adjuvant chemotherapy significantly improves survival, but is highly toxic and costly. Although high EGFR expression has been associated with advanced tumor grade, recurrence and poor survival, this correlation is unclear.

Deng et al. evaluated the prognostic values of high EGFR expression in primary tumors and nodal metastases from 94 patients with stage I to IV colorectal cancer. The survival rates for patients with stage I and II tumors were much higher than those with stage III and IV tumors. High EGFR expression in the primary tumor was predictive of a poor survival, but this association was not observed in patients with stage III or IV disease. High EGFR expression in the lymph nodes, however, correlated with shorter survival for patients with stage III and IV disease. Concordant high EGFR expression in the primary tumor and lymph nodes increased the risk of death, whereas concordant EGFR negative primary tumor and lymph node samples had a protective effect.

The researchers conclude that EGFR expression can be discordant between primary tumors and metastatic lymph nodes, and that differences in the molecular expression of EGFR can predict a worse survival. High EGFR expression levels in metastatic lymph nodes may be a more accurate predictor of survival than its expression in the primary tissue. Further work assessing these markers and other stem-cell markers is planned.