Abstract
BACKGROUND: Upper tract urothelial carcinoma (UTUC) is a rare subtype of urothelial cancer, accounting for only 5–10% of cases, and is characterized by aggressive biological behavior. Recent advances in immune checkpoint inhibitors (ICIs) and antibody-drug conjugates (ADCs) have expanded therapeutic options for advanced UTUC. However, their combined use may increase the risk of immune-related adverse events, particularly interstitial lung disease (ILD). CASE PRESENTATION: This case involves a 76-year-old female patient diagnosed with UTUC. The patient was diagnosed with invasive high-grade urothelial carcinoma of the right kidney following a biopsy, after a routine physical examination revealed a space-occupying lesion in the right kidney. Due to the patient’s and her family’s refusal of surgical treatment, a targeted immunotherapy regimen combining ICIs and ADCs was chosen. After two treatments with toripalimab combined with vedotin, the patient developed clinical symptoms such as drowsiness and shortness of breath, and was diagnosed with severe pneumonia complicated by type I respiratory failure. While initial treatment with anti-infectives and glucocorticoids (methylprednisolone sodium succinate) led to some improvement, the patient’s condition rapidly deteriorated upon the discontinuation of the glucocorticoid. Given the patient’s history of immunotherapy and the worsening of her condition after the discontinuation of hormone therapy, the patient was ultimately considered to have developed immune-related lung disease (ILD) caused by toripalimab. With high-dose glucocorticoid pulse therapy and other supportive treatments, the patient’s condition was controlled and gradually stabilized, and she was subsequently discharged in stable condition. During the follow-up period, the patient continued vedotin treatment, without experiencing any significant adverse reactions. CONCLUSION: Although the combination of toripalimab and disitamab vedotin demonstrates efficacy in treating UTUC, it may also induce severe ILD. In clinical practice, it is essential to strictly adhere to indications, enhance monitoring and follow-up, and formulate individualized treatment decisions.