What happened, in summary

This 59-year-old man had a 20-year smoking history and first noticed a small raised nodule near the right nostril in April 2023. After scratching caused ulceration and bleeding, the nasal-tip area became red, swollen, and progressively larger despite antibiotics and local remedies. In May 2023, he also developed a mainly dry cough with occasional sputum and blood streaks. CT in July showed an 11 × 8.9 × 9.4 cm irregular mass in the middle and lower right lung near the hilum, with obstructive atelectasis and pneumonia. A nasal biopsy showed squamous cell carcinoma confined to the dermis and subcutaneous tissue without surface epithelial dysplasia, supporting metastatic disease rather than a primary skin cancer. Bronchoscopy also found squamous cell carcinoma at the right intermediate bronchus. Bone imaging showed abnormal uptake in the left acromion. Genetic testing found no mutations, and PD-L1 expression was 15%; ANA was 1:1000 and anti-RO-52 was positive. He was diagnosed with pulmonary squamous cell carcinoma, Stage IVA, T4N2M1b, with metastases to the nasal region and left acromion. Because of abnormal immune markers, treatment began with paclitaxel plus carboplatin alone. After 2 cycles, the lung lesion was slightly smaller but the nasal metastasis had enlarged. Tislelizumab was added from the third chemotherapy cycle. The nasal lesion then rapidly regressed, and the lung tumor continued shrinking on repeat chest CT. By January 2024, the nasal skin had largely returned toward normal. After 7 chemotherapy cycles and 5 tislelizumab doses, he moved to maintenance paclitaxel plus tislelizumab. Symptoms improved, no immune-related pneumonitis, colitis, or hepatitis occurred, and progression-free survival exceeded 12 months.