MEK inhibitors (trametinib, cobimetinib, selumetinib or binimetinib) have been used since 2016 to treat metastatic melanoma, by targeting the MAPK pathway Neuromuscular complications (neuropathy, myasthenia or myositis) have been reported in patients treated with MEK inhibitors.

With the growing use of these new oncology therapies, neurologists, oncologists and other clinicians are likely to be increasingly confronted with MEK inhibitor-induced neuropathy, myasthenia or myositis.

Yet, so far, these complications have only been documented in a few single case reports.

Our aim was to characterize the neuromuscular complications associated with MEK inhibitors used either alone or in combination.

Inclusion Criteria:

• Patients with neuromuscular complications of MEK inhibitors used alone or in combination
• Age > 18 years

Exclusion Criteria:

• Refusal of data collection

Patients with neuromuscular complications treated with MEK inhibitors at a Neuromuscular Reference Center in France