Dermatologic Complications of Cancer Therapies: Clinical Cases and Management

Conclusions

• Amivantamab can cause severe, refractory EGFR-like skin toxicity, and patients often need manual debridement plus aggressive topical therapy and occlusion to stay on treatment.
• For amivantamab-associated scalp and plaque reactions, gentle shampooing, topical steroids, topical antibiotics, and shower-cap occlusion can produce major functional improvement even if complete clearing is unlikely without a drug holiday.
• Immune checkpoint inhibitors can trigger eruptive squamous cell carcinomas and keratoacanthomas as a class effect, especially in predisposed patients, and stopping immunotherapy alone often does not resolve the lesions.
• Because immunotherapy-related eruptive SCC/keratoacanthomas are often numerous and bilateral, management is usually non-surgical and should be individualized, with intralesional corticosteroids being particularly effective in many cases.
• The presentation argues that these eruptive lesions are primarily driven by inflammation rather than true cancer burden, which is why anti-inflammatory treatment can lead to dramatic responses.
• Toxic erythema of chemotherapy is a unifying diagnosis for many chemotherapy rashes and should be recognized as a direct toxic skin effect rather than SJS, DRESS, or hand-foot syndrome.
• Supportive measures such as topical steroids under occlusion, cool packs, fans, and avoiding warm blankets can allow patients to continue chemotherapy with less skin toxicity.
• Immune checkpoint inhibitors can also cause rare but serious systemic toxicities such as cardiomyopathy, which may present with conduction abnormalities and can be life-threatening.
• When a skin cancer is easily removable by surgery or radiation, those options are preferred over indefinite immunotherapy because even effective immunotherapies can cause rare catastrophic complications.
• Overall, dermatologic adverse events from cancer therapies are often manageable enough to preserve oncologic treatment, but they require early recognition, practical supportive care, and close coordination with oncology.