Amivantamab, a bispecific monoclonal antibody designed to target both epidermal growth factor receptor (EGFR) and mesenchymal-epithelial transition factor (MET), has rapidly transformed the therapeutic landscape for patients with EGFR-mutant non-small cell lung cancer (NSCLC), delivering unprecedented clinical benefits. However, alongside its therapeutic promise, clinicians are increasingly encountering novel adverse events that reflect the complex interplay of targeted therapy with other treatment modalities such as radiotherapy. In a recently published case report in the peer-reviewed journal Oncoscience, researchers have elucidated a compelling example of such an interaction manifesting as an erosive pustular dermatosis (EPD)-like scalp reaction following cranial radiotherapy in a patient receiving amivantamab.
This groundbreaking report, led by Vasiliki Nikolaou and Ioannis-Alexios Koumprentziotis at the National and Kapodistrian University of Athens Medical School, describes a rare and previously undocumented cutaneous toxicity observed during combination treatment. The patient, afflicted with EGFR-mutant NSCLC, developed severe, painful erosive lesions characterized by crusted plaques exclusively confined to areas of the scalp that had been previously exposed to cranial radiation. This distinct dermatologic presentation diverges from the typical amivantamab-associated skin reactions such as acneiform eruptions and xerosis, suggesting a hitherto unrecognized synergism between radiotherapy-induced tissue injury and the pharmacodynamics of dual EGFR/MET blockade.
Mechanistically, the dual inhibition of EGFR and MET is hypothesized to disrupt critical signaling pathways that govern keratinocyte proliferation, differentiation, and repair. EGFR signaling is integral to epidermal homeostasis and wound healing, facilitating cellular proliferation and migration at sites of injury. Likewise, MET activation promotes tissue regeneration and modulates inflammatory responses. Targeted blockade of both receptors, therefore, could attenuate the regenerative capacity of irradiated skin, impeding appropriate wound healing after radiotherapy’s cytotoxic insult. This biological impairment likely culminates in the ulcerative, inflammatory scalp lesions reminiscent of erosive pustular dermatosis.
Radiotherapy induces acute and chronic modifications in the microenvironment of irradiated tissues, triggering inflammatory cascades, vascular damage, and fibrosis. When this milieu is superimposed with targeted therapy that compromises essential repair mechanisms, the risk of severe cutaneous adverse effects escalates. This interplay underscores a critical need for heightened vigilance and dermatologic evaluation in patients undergoing concurrent or sequential radiation and amivantamab treatment. Recognizing the unique pattern of scalp ulcerations confined to irradiated fields enables timely diagnosis and optimizes clinical management.
Importantly, in the reported case, early initiation of topical corticosteroids combined with supportive care resulted in significant clinical improvement without necessitating the cessation of amivantamab therapy. This outcome not only emphasizes the potential to manage such toxicities conservatively but also highlights the paramount importance of distinguishing EPD-like reactions from alternative diagnoses that might lead to unwarranted treatment interruption. Maintaining uninterrupted cancer therapy in such scenarios can substantially impact overall patient prognosis and quality of life.
This case report also catalyzes broader reflection on the evolving complexity of adverse event profiles associated with contemporary targeted agents, particularly when used in multimodal regimens. As oncology pivots towards increasingly personalized and combinatorial approaches, drug-radiation interactions present novel challenges that demand integrated therapeutic strategies and multidisciplinary collaboration. Enhanced understanding of molecular pathobiology underpinning these reactions will be instrumental in devising prophylactic measures and tailored interventions.
From a research standpoint, future investigations should aim to elucidate the cellular and molecular dynamics driving impaired healing in the context of dual EGFR/MET inhibition post-radiotherapy. Animal models and translational studies may offer insights into modulating critical pathways or identifying biomarkers predictive of susceptibility to such cutaneous toxicities. Additionally, therapeutic modifications, dosing schedules, or adjunctive agents could potentially mitigate risk without compromising antitumor efficacy.
Clinicians are encouraged to maintain a high index of suspicion for erosive pustular dermatosis-like eruptions in patients receiving amivantamab with a history of cranial or scalp irradiation. Patient education regarding early dermatologic symptoms and prompt referral to dermatology specialists can facilitate rapid intervention. By fostering multidisciplinary communication and applying evidence-based management principles, healthcare providers can minimize treatment disruptions and optimize patient outcomes in this complex clinical setting.
Overall, this compelling report not only expands the spectrum of known amivantamab-associated adverse events but also serves as a paradigm illustrating the intricate interplay between targeted therapies and radiation-induced tissue responses. As novel agents continue to redefine oncology treatment paradigms, meticulous post-marketing surveillance and case documentation remain crucial in identifying and characterizing rare but impactful toxicities.
In conclusion, the identification of an erosive pustular dermatosis-like scalp reaction following cranial radiotherapy in a patient treated with amivantamab underscores the necessity for awareness of emerging dermatologic complications associated with next-generation targeted therapies. This insight reinforces the importance of early recognition, appropriate therapeutic adaptation, and the collaborative efforts required to safely harness the full potential of advanced oncologic treatments.
DOI: https://doi.org/10.18632/oncoscience.649
Subject of Research: People
Article Title: Erosive pustular dermatosis–like scalp reaction following cranial radiotherapy in a patient with EGFR-mutant NSCLC treated with amivantamab
News Publication Date: 11-Mar-2026
Web References: https://doi.org/10.18632/oncoscience.649
Image Credits: Copyright: © 2026 Nikolaou et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0).
Keywords: cancer, amivantamab, lung cancer, cutaneous toxicity, erosive pustular dermatosis, radiotherapy
Tags: Amivantamab scalp reactionbispecific monoclonal antibody skin reactionscombination therapy scalp lesionscranial radiotherapy dermatologic complicationsdual EGFR and MET inhibition side effectsEGFR-mutant non-small cell lung cancer treatmenterosive pustular dermatosis after radiotherapynovel adverse events in lung cancer therapyNSCLC targeted treatment toxicitiespharmacodynamics of EGFR/MET blockaderadiotherapy-induced cutaneous toxicitytargeted therapy and radiotherapy interaction
