What happened, in summary

A 60-year-old man was diagnosed in August 2024 with Stage II lung squamous cell carcinoma after months of worsening cough and breathlessness. Surgery was considered unsuitable, so he began treatment with paclitaxel, carboplatin, and the immunotherapy drug camrelizumab.

After the first cycle, he developed itchy papules that gradually spread across his arms, face, neck, and trunk. The rash became worse after the second and third cycles and did not improve with initial treatment for presumed eczema. Further evaluation and a skin biopsy supported a diagnosis of immune-mediated subacute cutaneous lupus.

Camrelizumab was stopped. He received topical treatment, oral prednisone, hydroxychloroquine, and sun-protection measures, with marked improvement in itching within days and gradual fading of the rash. Imaging meanwhile showed that the lung cancer had responded. Because surgery was not feasible, he subsequently received radical radiotherapy. At the latest follow-up, the immunotherapy remained discontinued and his cancer was being actively monitored.