The challenge of managing a cetuximab rash

Epidermal growth factor receptor antibodies (EGFR) such as cetuximab have been approved for use as first-line management as well as salvage therapy for head and neck and colorectal cancers. Among the most common expected toxicity is a cutaneous eruption described as acneiform. The presence of a rash has been postulated to predict a more favorable treatment outcome for cancers of the head and neck¹ but not for colorectum.² With more severe drug reactions, patients may require a treatment break, which has been shown to reduce locoregional control and survival, particularly in patients with head and neck cancer.³ This has prompted clinicians to affect rapid therapy to reverse the drug eruption. Given the controversy around rapid and effective reversal of this drug reaction, this report aims to address the current status of clinical management using an actual patient vignette.

Case presentation and summary

The patient was a 57-year-old white man who had been diagnosed with stage 4 T4N0M1 grade 3 cutaneous squamous cell carcinoma (SCC) of the right postauricular soft tissues, with erosion into the right mastoid and biopsy-proven metastatic disease involving the contralateral left supraclavicular fossa and bilateral lungs. His disease became chemotherapy-refractory, and he was referred for palliative local therapy to the base of skull. Because of the size of the tumor (4 cm × 5 cm), he was considered for sensitizing chemotherapy, but cisplatin was not appropriate because of chronic hearing loss.⁴ The patient was recommended sensitizing doses of cetuximab. This EGFR antibody has been shown to offer similar benefits to those seen with cisplatin in the definitive management of head and neck SCC.⁵

The standard loading dose of cetuximab was given at 400 mg/m² intravenously (IV). The following week, the sensitizing dose of 250 mg/m² IV was given along with daily radiotherapy to the target volumes. The weekly dose of cetuximab continued at 250 mg/m². The radiotherapy prescription was for 6,000 cGy in 200 cGy daily fractions, encompassing the gross tumor volume as identified on a computed-tomographic scan with 3-mm cuts. We used a noncoplanar arc radiotherapy beam arrangement because it inherently spreads the dose over a larger volume of normal tissue while conformally delivering its largest dose to the gross tumor volume. As such, a volume of the patient’s oropharynx and oral cavity was included within the radiotherapy dose penumbra. After receiving 3 weekly doses of cetuximab (1 loading dose and 2 weekly sensitizing doses) and 2,000 cGy of radiotherapy, the patient developed a robust grade 2 cutaneous eruption delimited to the face, with few scattered lesions on the upper anterior chest. He was seen in the medical oncology department and was prescribed doxycycline 100 mg orally twice daily and topical clindamycin 2% ointment twice daily.

In the radiation oncology clinic, his drug therapy was manipulated. His cetuximab cutaneous reaction was a grade 2, manifested by moderate erythema with nonconfluent moist desquamation. Because of concern that the patient would develop oral candida, which would further delay his therapy, the oral and topical antibiotics were discontinued, as was the oral prednisone. He was prescribed triamcinolone cream 0.1% to be applied to the facial and few chest wall areas twice daily and an oncology mouth rinse to address early nonconfluent mucositis. The accompanying images show the extent of the patient’s cetuximab cutaneous reaction at baseline before treatment initiation (Figure 1), at 4 days after the intervention (Figure 2), and again at 6 days after the intervention (Figure 3). The patient consented to having his photographs taken and understood that they would be used for educational and research publication purposes.

As can be seen from the photographs, the patient’s rash began to dry and peel by day 4 after the intervention, and there were no new eruptions. The pruritus that accompanied the rash had entirely resolved. By day 6, the rash had completely subsided. Because of the response to the topical steroid, the patient continued cetuximab without a dose modification. He was recommended to continue with the triamcinolone cream until the chemoradiotherapy course concluded.