What happened, in summary

A 67-year-old Caucasian man with EGFR-positive non-small cell lung cancer developed a painful, itchy papulopustular rash on both lower legs about 2 weeks after starting erlotinib. The skin reaction caused stinging, pruritus, visible erythema, and a reduced quality of life. His team first used standard supportive measures for EGFR inhibitor-related rash: topical steroids, topical clindamycin, and oral doxycycline. These treatments did not control the symptoms. The usual next step would have been lowering the erlotinib dose or stopping the drug, but that could have interrupted a targeted therapy expected to provide oncologic benefit. After shared decision-making, the team chose low-dose intravenous immunoglobulin, or IVIG, together with dilute stem-cell therapy as a way to manage the rash while preserving lung cancer treatment. The approach was aimed at controlling suspected bacterial overgrowth contributing to the skin toxicity while avoiding unnecessary immune suppression. The response was rapid. Within the first 24 hours, the rash improved by about 70%. Within 96 hours, it had completely resolved. He was then able to continue erlotinib without recurrence of the skin findings. The key result was successful toxicity management: a severe erlotinib-related rash was controlled without stopping targeted therapy, allowing him to stay on his oral lung-cancer medicine and avoid a dose reduction. This mattered because dose reduction can limit the intended benefit of EGFR-directed treatment. Skin reactions, although outside the tumor itself, can become cancer-care problems when they threaten adherence to oral targeted therapy. By controlling the rash quickly, the team preserved symptom relief and continuity of erlotinib in daily cancer care.