Clinical Scorecard: Elevated TROP-2 Levels in Papillary Renal Cell Carcinoma Indicate Its Promise as a Target for Antibody-Drug-Conjugate Treatment

At a Glance

Key Highlights

• pRCC accounts for approximately 15% of all renal cell carcinoma cases and has limited evidence-based treatment options compared to clear cell RCC.
• Immune-oncology (IO)-based therapies improve progression-free survival and response rates over tyrosine kinase inhibitors in metastatic pRCC.
• TROP-2 is overexpressed in pRCC and represents a promising target for antibody-drug conjugate therapy, exemplified by sacituzumab govitecan.

Guideline-Based Recommendations

Diagnosis

• Histopathological classification of RCC subtypes according to WHO and TNM criteria.
• Assessment of TROP-2 expression in tumor tissue via immunohistochemistry (IHC) using H-score method.
• Measurement of TROP-2 mRNA levels by RT-qPCR and serum TROP-2 by ELISA as potential biomarkers.

Management

• Consider immune-oncology-based combination therapies as first-line treatment for metastatic pRCC.
• Explore antibody-drug conjugates targeting TROP-2, such as sacituzumab govitecan, in clinical trials or investigational settings.
• Surgical intervention (partial or radical nephrectomy) remains standard for localized disease.

Monitoring & Follow-up

• Monitor progression-free survival and overall survival outcomes during systemic therapy.
• Evaluate objective response rates to assess treatment efficacy.
• Potential use of serum TROP-2 levels as surrogate markers for tumor expression and treatment response.

Risks

• Limited second-line treatment options and historically poor prognosis in metastatic nccRCC including pRCC.
• Potential systemic toxicity from ADCs, although targeted delivery aims to minimize this.
• Need for further validation of TROP-2 as a predictive biomarker and therapeutic target.

Patient & Prescribing Data

Patients with metastatic papillary renal cell carcinoma enrolled in retrospective and clinical studies.

Immune-oncology combinations show superior progression-free survival and response rates compared to tyrosine kinase inhibitors; sacituzumab govitecan demonstrates preclinical activity targeting TROP-2.

Clinical Best Practices

• Use standardized histopathological and molecular assays to confirm RCC subtype and TROP-2 expression.
• Incorporate immune-oncology therapies as preferred systemic treatment in metastatic pRCC.
• Consider enrollment in clinical trials evaluating TROP-2-targeted ADCs for patients with high TROP-2 expression.
• Collect and analyze serum samples preoperatively to correlate circulating TROP-2 with tumor burden.
• Apply multidisciplinary care involving urology, medical oncology, and pathology for optimal management.

References

• ARON-1 Study on metastatic pRCC treatment outcomes
• WHO Classification of Tumors of the Urinary System and Male Genital Organs, 5th Edition
• Sacituzumab Govitecan clinical trials ASCENT and TROPHY-U-01
• TROP-2 expression and antibody-drug conjugate mechanisms