Origins of lymphatic and distant metastases in human colorectal cancer

Metastases undergo reconstruction Cancer cells from primary tumors can migrate to regional lymph nodes and distant organs. The prevailing model in oncology is that lymph node metastases give rise to distant metastases. This “sequential progression model” is the rationale for surgical removal of tumor-draining lymph nodes. Naxerova et al. used phylogenetic methods to reconstruct the evolutionary relationship of primary tumors, lymph node metastases, and distant metastases in 17 patients with colorectal cancer (see the Perspective by Markowitz). The sequential progression model applied to only one-third of the patients. In the other two-thirds, distant metastases and lymph node metastases originated from independent subclones within the primary tumor. Science , this issue p. 55 ; see also p. 35