Numb Chin Syndrome (NCS) is a heterogeneous condition of mental nerve neuropathy playing in concert with multiple disease mechanisms, but all result in a disruption of unilateral or bilateral facial nerves, fever, and swelling of the lower lip. The NCS has been reported as a prodromal symptom of pending malignancies, a possible precursor of cancer or leukemia, and sometimes merely a benign, painful or annoying, condition. However, any causal relationships between the NCS and malignancy have not been made, were not aggregated, and therefore remain unclear. This thorough review of all the available current literature in the PubMed interface was performed by using the key words, “mental neuropathy,” “mental nerve numbness,” and “numb chin syndrome.” There were 186 peerreviewed articles reporting 550 patients from 28 countries worldwide including 150 benign, 398 malignant, and 2 unknown cases. The seven most common malignancies from high to low frequency were: lymphoma, bone cancer, oral cancer, breast cancer, brain cancer, leukemia, and prostate cancer. While the clinical implications of the NCS are not fully understood, this delineative study will aid physicians confronted and confounded with various malignancies, neuropathies, and cytogenetic abnormalities of patients initially presenting with the symptom of a numb chin.