Scientists have discovered the first known instance of a tapeworm-derived cancerlike infection in a human. A man infected with HIV succumbed to the unusual condition just days after scientists uncovered its cause: abnormal, rapidly proliferating cells of the dwarf tapeworm (Hymenolepis nana). He had initially fallen ill in 2013.
During diagnostic examination, biopsy samples from the patient’s lymph nodes and from tumors in his lungs were found to contain unusually small cells, clearly not human in origin yet exhibiting morphological traits and behavioral features typical of malignant, cancer-causing cells. During months of investigation, scientists performed extensive analyses of the cells’ DNA and tumor-associated proteins, which revealed and confirmed the identity of the tapeworm cells. Genetic abnormalities underlying the uncontrolled growth of the tapeworm cells were consistent with complex genetic alterations described in mammalian cancers.
The unusual case was described in detail in a report published in the New England Journal of Medicine in early November 2015. The dwarf tapeworm is the most-common infectious cestode in humans. Researchers suspect that its ability to grow uncontrollably, giving rise to tumors, is limited to persons whose immune systems are compromised.
Source: http://www.britannica.com/story/tapeworm-leads-to-cancerlike-infection