PET/CT Illustration of Metastatic Breast Cancer to the Left Mandibular Foramen

Abstract

Mental nerve neuropathy (numb chin/lip syndrome) is a sensory neuropathy presenting with numbness in the distribution of the inferior alveolar nerve/mental nerve (chin and lower lip). This is typically unilateral and can be secondary to dental disease or malignancy. When caused by malignancy, these symptoms can be either an initial presentation of an unsuspected tumor or progressive metastatic disease, both of which would indicate poor prognosis. We describe a 48-year-old female patient with a history of breast cancer who presented with left chin numbness and manifested a metastatic lesion involving the left mandibular foramen on PET/CT and subsequent MRI.

Mental Neuropathy as Initial Manifestation of Metastatic Breast Cancer: A Case Report and Review of the Literature

“…Mental neuropathy (numb chin syndrome) is caused by damage to the inferior alveolar nerve, responsible for innervation of the chin and lower lip. This nerve is a branch of the trigeminal nerve and is mostly sensory; thus, patients with neuropathy of this nerve experience change of sensation in the affected area [1][2][3][4]17,18]. Several conditions and diseases, including benign and malignant, can be the cause of this neuropathy.…”

“…The interval between the emergence of neuropathy, as the first symptom, and diagnosis of neoplasia has not been generally mentioned but Sudha (41) 2015 56 F Breast carcinoma Metastatic + García-Lamazares (27) 2014 62 F Breast cancer Metastatic -Chapa (29) 2014 39 F Breast sarcoma Metastatic Delayed + 5 months Barman (9) 2014 52 F Breast carcinoma Metastatic ? * Kota (18) 2013 48 F Breast cancer Metastatic ? * Oravivattanakul (42) 2013 51 F Breast cancer Metastatic ?…”

“…Since the reporting of neuropathy has often been associated with malignancies rather than other systemic diseases, patients who present with the apparently minor complaint of sensory impairment and numbness of the mental region should be examined carefully and systematically to determine the underlying cause of this condition. Kota (18) 2013 48 -+ -? * Oravivattanakul (42) 2013 51 ?…”