Which drug is associated with dermatological toxicity in the form of an acneiform rash?

Cetuximab (Erbitux) is well-known for its association with dermatological toxicities, particularly an acneiform rash. This type of rash is a common adverse effect due to the drug's mechanism of action, which involves targeting the epidermal growth factor receptor (EGFR). The inhibition of EGFR can disrupt normal skin homeostasis, leading to conditions such as acneiform eruptions. These rashes can occur as early as the second week of treatment and often present on areas of the face, chest, and back.

While other treatments, like Pembrolizumab, Trastuzumab, and Bevacizumab, can cause various side effects, they are not primarily associated with acneiform rashes. Pembrolizumab, for instance, is more commonly linked with immune-related adverse effects, including skin toxicity, but not specifically with an acneiform rash. Trastuzumab predominantly targets HER2-positive cancers and has side effects related to cardiac function rather than skin reactions. Bevacizumab is an anti-VEGF therapy noted for different adverse effects such as hypertension and bleeding, not dermatological ones.

Thus, the identification of Cetuximab as the drug causing an acneiform rash is consistent with established clinical