From the Guidelines
There is a risk of neuropathy in Multiple Endocrine Neoplasia (MEN), particularly in the MEN2B subtype, due to the development of mucosal neuromas and intestinal ganglioneuromatosis. This condition can cause gastrointestinal symptoms and altered bowel function, as well as a marfanoid habitus with elongated limbs and skeletal abnormalities 1. In MEN2A, although less common, some patients may experience symptoms related to pheochromocytomas that can mimic neuropathic symptoms due to catecholamine excess, including paresthesias and pain.
The neurological manifestations in MEN syndromes are related to the underlying genetic mutations, particularly in the RET proto-oncogene for MEN2, which affects neural crest-derived tissues 1. It's worth noting that the risk of neuropathy in MEN is not solely related to the condition itself, but also to the treatments used, such as systemic anticancer therapy, which can induce peripheral and central neurotoxicity 1.
Key points to consider in the management of MEN patients include:
- Early genetic testing to identify specific mutations and guide management and surveillance strategies
- Regular neurological evaluations to monitor for development or progression of neurological complications, particularly in MEN2B patients
- Awareness of the potential for neuropathic symptoms due to catecholamine excess in MEN2A patients with pheochromocytomas
- Consideration of the potential neurotoxic effects of treatments used in MEN patients, such as systemic anticancer therapy 1.
From the Research
Risk of Neuropathy in Multiple Endocrine Neoplasia (MEN)
There are no direct studies that link Multiple Endocrine Neoplasia (MEN) to a risk of neuropathy. However, some studies provide insight into the relationship between neuroendocrine tumors and neuropathy:
- Neuroendocrine tumors, which are associated with MEN, have been studied in the context of their diagnosis and management 2.
- The treatment of neuroendocrine tumors may involve chemotherapy, which can cause chemotherapy-induced peripheral neuropathy (CIPN) 3, 4.
- Functional vitamin B12 deficiency has been identified as a potential cause of neuropathy in patients with advanced malignancy, including those with neuroendocrine tumors 5.
- Concomitant medications and comorbidities, such as cardiovascular drugs and preexisting nerve compression syndromes, can increase the risk of neuropathy in patients receiving chemotherapy 4.
Key Findings
- Chemotherapy-induced peripheral neuropathy is a common adverse effect of cancer treatment, affecting up to 40% of survivors 4.
- Neuroendocrine tumors can be treated with somatostatin analogs, interferon-alpha, and chemotherapy, but the risk of neuropathy associated with these treatments is not well established 2, 6.
- Further research is needed to determine the risk of neuropathy in patients with MEN and to identify effective strategies for prevention and treatment.
Relevant Studies
- A study on functional vitamin B12 deficiency in advanced malignancy found that B12 therapy decreased MMA values and improved neurologic findings in some subjects 5.
- A review of toxic peripheral neuropathy associated with chemotherapeutic agents highlighted the need for further research on the pathogenesis, incidence, and management of CIPN 3.
- A study on concomitant medications and risk of chemotherapy-induced peripheral neuropathy identified several factors associated with an increased risk of neuropathy, including older age, cardiovascular drugs, and preexisting nerve compression syndromes 4.