What happened, in summary

An 83-year-old woman developed a rapidly spreading blistering skin eruption that began on sun-exposed areas and eventually involved more than half of her body surface. Skin biopsy supported subacute cutaneous lupus, and later samples showed full-thickness epidermal necrosis. Laboratory testing showed high antinuclear and anti-SSA antibodies without fever or another systemic abnormality. The pattern resembled toxic epidermal necrolysis, but the timing of her long-term medications made a drug reaction unlikely. Hydroxychloroquine was continued, and three days of high-dose intravenous methylprednisolone produced rapid improvement and discharge within two weeks.

During the evaluation, a routine chest X-ray revealed a lung nodule. Further assessment identified stage IA small cell lung carcinoma, T1bN0M0. The cancer had been found incidentally rather than through respiratory symptoms. The tumor was removed with a left lower lobectomy. No chemotherapy, radiation, or other lung-cancer treatment was documented.

At one-year follow-up, the lung cancer was in remission. Her lupus-related skin and systemic findings had also resolved, antinuclear-antibody levels returned to normal, and hydroxychloroquine was stopped. The skin disease did not recur during two years of follow-up. The close timing between the severe skin disorder and cancer, followed by sustained improvement after tumor removal, supported a possible paraneoplastic relationship. The report therefore links an unusual dermatologic presentation with the incidental discovery of a surgically treated early-stage lung cancer.