Neoadjuvant Disitamab Vedotin, Toripalimab, and Radiotherapy for High-risk UTUC ( LUXUS07.1 )

High-risk UTUC is associated with a substantial risk of recurrence and metastasis after radical surgery. Many patients are unable to tolerate cisplatin-based perioperative chemotherapy because of impaired renal function or treatment-related toxicity. Radiotherapy may improve local control, and low-dose radiation may also modulate the tumor immune microenvironment. Combining an antibody-drug conjugate, immune checkpoint blockade, and sequential radiotherapy before surgery may provide systemic tumor control, enhance local tumor response, and improve pathological downstaging.

This study will enroll patients with resectable, non-metastatic, high-risk UTUC at Peking University First Hospital. Patients will undergo baseline imaging, pathological confirmation, biomarker evaluation, and collection of blood, urine, and tumor specimens. A safety run-in phase of 6 patients will be used to evaluate early safety and dose-limiting toxicities during the first treatment cycle, with special attention to days 7-14. If the safety threshold is met, an additional 14 patients will be enrolled. Interim efficacy assessment will be performed before the penultimate systemic treatment cycle to guide subsequent radiotherapy and surgical planning. Patients will then undergo radical surgery when clinically appropriate and will be followed for recurrence, metastasis, survival, safety, and exploratory molecular endpoints.

Inclusion criteria

• Age ≥18 years, male or female.
• Imaging evaluation before treatment excludes distant organ metastasis or other concurrent malignancy and suggests resectable high-risk UTUC.
• Completed pathological biopsy with a clear pathological diagnosis : including puncture biopsy, ureteroscopy and urine cytology, at least one of which is clearly diagnosed as uroepithelial carcinoma, which may include no more than 50% or more proportion of squamous, adenoid, sarcomatoid differentiation and other special differentiation types;
• High-risk features, including muscle-invasive disease, high-grade tumor, multifocal disease, tumor diameter ≥2 cm, hydronephrosis, or regional lymph node involvement.
• HER2 expression by immunohistochemistry 1+ to 3+; PD-L1 expression not restricted.
• Have the willingness to undergo radical surgical treatment and perioperative adjuvant treatment, have good compliance, and be able to co-operate with the treatment and follow-up plan specified by the clinician;
• Postoperative life expectancy of at least 6 months; ECOG score ≤ 2.

Exclusion criteria

• Distant metastases or other malignant neoplastic diseases combined with other malignant neoplasms in the same period had been detected at the time of surgery, or the present was a progression after palliative resection of previous epithelial carcinoma of the urothelium;
• History of pelvic and abdominal radiotherapy; history of inflammatory bowel disease; history of systemic chemotherapy;
• Pregnant women or breastfeeding women; or women of childbearing potential who are not using reliable contraception;
• The presence of active infections in those with pre-existing or coexisting haemorrhagic disorders
• clinically significant cardiac disease (e.g., hypertension controlled with medications, unstable angina, New York Heart Association (NYHA) class ≥II congestive heart failure, unstable symptomatic arrhythmias, or class ≥II peripheral vascular disease);
• Psychological, familial, and social factors leading to lack of informed consent.