Cancer stem cells, albeit a rare cell population, are the cells that drive tumor growth, and are believed to be responsible for causing cancer relapse following therapies. Tumor invasion and metastases are likely the result of migration of the cancer stem cells either locally or to distant sites. Thus, methods for identifying and visualizing these cells in pathological specimens should greatly benefit both cancer research and patient care. The identification and isolation of cancer stem cells provides a diagnostic/prognostic tool for classifying the cancer so that an appropriate treatment regimen can be pursued. Furthermore, such isolated cancer stem cells can be used to screen for chemotherapeutic agents that are effective in eradicating these cancer stem cells.Stanford researchers from Prof. Irv Weissman's laboratory have isolated and characterized such cancer stem cells from patients with head and neck squamous cell carcinoma. This discovery will provide a valuable source of tissue for cancer stem cell research, and it will provide a rapid way to analyze pathologic specimens for invasion of cancer stem cells into neighboring tissue and distant metastatic sites, as well as responses to therapies. Finally, the detection of cancer stem cells in patient tissues will aid in classifying the malignancy and in choosing the appropriate treatment strategy. [ - ]

Cancer stem cells, albeit a rare cell population, are the cells that drive tumor growth, and are... [ + ]