Monitoring and treatment for select toxicities associated with MEK inhibitors
| Toxicity | Management |
| Cutaneous skin reactions*107 108 122 | Treatment options include oral or topical antibiotics and corticosteroids and isotretinoin108
Preventative measures include emollients and use of high-SPF sunscreen108 |
| Diarrhea122 | Management consists of loperamide, diet modifications, fluid and electrolyte intake, and dose interruption (grade 2–3) or discontinuation (grade 4). Infection should be ruled out and antibiotics given for persistent grade 3–4 diarrhea or in the case of grade 3–4 neutropenia106 |
| Peripheral edema122 | Evaluate with standard cardiac work-up including ECG, echocardiogram, and referral to cardiologist if appropriate106 |
| Cardiac toxicity†122 | Assess LVEF by echocardiogram or MUGA scan before initiation of trametinib, 1 month after initiation, and then every 2–3 months during treatment.123 Follow instructions in product labeling in the event of decreased LVEF |
| Ocular toxicity‡109 122 | Ensure patient has ophthalmology follow-up with proactive monitoring for ocular toxicities.107 Urgent ophthalmological evaluation should occur within 24 hours for loss of vision or other visual disturbances123
Counsel patient about the possibility and timing of ocular toxicity, which most commonly occurs within 14 days after treatment initiation124 |
| Interstitial lung disease or pneumonitis106 | Patients who develop cough, shortness of breath, or abnormal chest signs should be evaluated for pneumonitis with plain chest X-ray or chest CT scan106
Treatment consists of temporarily discontinuing MEK inhibitor treatment and initiating an oral steroid125 |
*Most frequently acneiform dermatitis, rash (maculo-papular, erythematous, or exfoliative), erythema, folliculitis, erysipelas.108
†Decreased ejection fraction, ventricular dysfunction.122
‡MEK inhibitor-associated toxicities: blurred vision, chorioretinopathy, retinal vein occlusion, retinal pigment epithelial detachment122 123; BRAF inhibitor-associated toxicities: retinal vein occlusion.109
CT, computed tomography; LVEF, left ventricular ejection fraction; MEK, mitogen-activated extracellular signal-regulated kinase; MUGA, multi-gated acquisition; SPF, sun protection factor.