Natural-Killer T-Cell Lymphoma (NKTCL) susceptibility prediction, diagnosis and therapy. The invention relates to a method for predicting Natural Killer T-cell Lymphoma (NKTCL) susceptibility and/or diagnosing NKTCL in a subject comprising testing for JAK mutations. The invention also relates to a method of screening for candidate agents capable of treating NKTCL using a cell line comprising at least one JAK mutation. The invention includes an NKTCL animal model comprising at least one JAK mutation. The invention also includes JAK inhibitors for treating NKTCL.
