February 19, 2014
The Number Of Tumor Cells Spread To Sentinel Lymph Nodes Affects Melanoma Prognosis
Cancer cell spread to the sentinel node—the lymph node to which cancer cells are most likely to spread from a primary tumor—is a risk factor for melanoma death. According to a study published in this week's PLOS Medicine by Anja Ulmer, Christoph Klein and colleagues from the Universities of Tübingen and Regensburg, Germany, the prognosis of a patient largely depends on the number of disseminated cancer cells per million lymphocytes in the sentinel node. Even very low numbers were found to be predictive for reduced survival.
The leading cause of death from skin disease is melanoma, which is the most dangerous type of skin cancer. When melanoma metastasizes and spreads to other parts of the body, treatment options become limited and the prognosis is poor. Melanoma staging (and prognosis) is currently focused on the primary tumor itself, with characteristics like tumor thickness, mitotic rate, and ulceration (break in the skin caused by the tumor) indicating the likelihood that the tumor has started to spread. Looking for tumor cells in the sentinel nodes is done for patients who are at increased risk for spread, but standard procedures for how to measure spread to the nodes and how to integrate this information with the tumor histology are needed. Since melanoma is one of the deadliest cancers, better predictors of prognosis for melanoma patients are needed for patient information and to determine treatment options.
These results need to be validated in an independent study, however, in order to establish how this methodology could be used in a clinical setting.
The authors say: "Our study shows that the extent of metastatic dissemination largely determines the disease courses of patients. The better we are able to predict the risk of patients to die from melanoma the better can we balance cost and benefit of potentially toxic therapies. For early melanoma, this might become even more important as novel drugs to prevent lethal metastasis are currently under investigation.
On the Net: