Mental nerve neuropathy: frequently overlooked clinical sign of hematologic malignancies

Neuropathies associated with lymphoma†

Neuropathy occurs with various manifestations as a consequence of lymphoma, and an understanding of the etiology is necessary for proper treatment. Advances in medical imaging have improved the detection of peripheral nerve involvement in lymphoma, yet tissue diagnosis is often equally important. The neoplastic involvement of the peripheral nervous system (PNS) in lymphoma can occur within the cerebrospinal fluid (CSF), inside the dura, or outside of the CSF space, affecting nerve root plexuses and peripheral nerves. The infiltration of either cranial or peripheral nerves in lymphoma is termed neurolymphomatosis (NL). These infiltrations can occur as mononeuropathy, multifocal neuropathy, symmetric neuropathies, or plexopathies. In rare cases, intravascular lymphoma (IL) can affect the PNS and an even rarer condition is the combination of NL and IL. Immune-mediated and paraneoplastic neuropathies are important considerations when treating patients with lymphoma. Demyelinating neuropathies, such as Guillain-Barré syndrome and chronic inflammatory demyelinating polyradiculoneuropathy, occur more frequently in non-Hodgkin's lymphoma than in Hodgkin's disease. Paraproteinemic neuropathies can be associated with lymphoma and paraneoplastic neuropathies are rare. While the treatment of lymphomas has improved, a knowledge of neurotoxic, radiotherapy, neoplastic, immune-mediated and paraneoplastic effects are important for patient care.

Numb chin syndrome with vagal and hypoglossal paralysis: an initial sign of an uncommon diagnosis

In this study, the case of a 58-year-old man with a 2-month history of left chin paresthesia with difficulty swallowing and chewing, and dysphonia is reported. He had an absence of the gag reflex, unilateral palatal palsy and deviation of the tongue upon attempted protrusion with unilateral atrophy. Magnetic resonance imaging of the skull base revealed a tumoral infiltration of the left side of Meckel's cave, involvement of the clivus with extension into the cavernous sinus and signs of focal leptomeningeal infiltration. The patient was eventually diagnosed with generalized Burkitt's lymphoma. In this study, the authors suggest an initial diagnostic workup that includes a computed tomography scan of the mandible and a magnetic resonance imaging of the skull base searching for malignancy in patients with isolated numb chin syndrome, a rare disorder often associated with cancer, especially breast cancer and lymphoma, with mandibular metastases, leptomeningeal seeding and metastases of the base of the skull explaining the origin of the syndrome in most cases.