How should an adolescent with clear‑cell renal cell carcinoma metastatic to the pleura be managed?

Management of Adolescent Clear-Cell Renal Cell Carcinoma with Pleural Metastases

An adolescent with metastatic clear-cell renal cell carcinoma to the pleura should be treated with first-line immune checkpoint inhibitor (ICI)-based combination therapy—specifically an ICI plus VEGFR tyrosine kinase inhibitor (TKI) regimen—prioritizing rapid disease control in this aggressive presentation, while cytoreductive nephrectomy should only be considered after achieving deep response to systemic therapy or for palliation of symptoms. 1, 2

Systemic Therapy: The Primary Treatment Approach

The cornerstone of management is immediate systemic therapy, not surgery. Current guidelines strongly recommend ICI-based combinations as first-line treatment for metastatic clear-cell RCC 1, 2. For an adolescent with pleural metastases (indicating intermediate-to-poor risk disease with metastatic burden), the preferred options include:

• Cabozantinib + nivolumab (CheckMate 9ER: OS HR 0.70, PFS HR 0.56, ORR 56%) 2
• Lenvatinib + pembrolizumab (CLEAR trial: OS HR 0.72, PFS HR 0.42, ORR 69%, CR rate 17%) 2
• Axitinib + pembrolizumab (KEYNOTE-426: OS HR 0.73, PFS HR 0.68, ORR 60%) 2

The ICI plus VEGFR-TKI combinations are particularly appropriate here because they provide rapid disease control, which is critical in an adolescent with symptomatic pleural involvement. 3 While dual ICI therapy (ipilimumab + nivolumab) is an option, it may be less suitable when rapid tumor shrinkage is needed 3.

Pediatric Considerations

Although these trials enrolled adults, case reports demonstrate that adolescents can tolerate and respond to targeted agents 4. The 14-year-old patient described responded to multiple lines including sorafenib, bevacizumab, sunitinib, and everolimus, though toxicities included hypothyroidism and significant hypertension 4. Close monitoring for treatment-related adverse effects is essential, particularly hypertension, hypothyroidism, and immune-related toxicities.

Role of Cytoreductive Nephrectomy

Upfront cytoreductive nephrectomy is NOT recommended in this scenario. 1 Current guidelines have moved away from routine upfront surgery in the ICI era, as systemic therapy should be prioritized 1.

CN may be considered only in highly selected circumstances:

• After achieving deep, durable response to systemic therapy (consolidation approach) 1
• For palliation if the primary tumor causes significant symptoms 1
• Low IMDC risk (0-1 points), low metastatic burden, excellent performance status, no brain metastases—criteria unlikely to be met with pleural metastases 1

The decision requires multidisciplinary discussion, but in an adolescent with pleural metastases, the metastatic burden argues strongly against upfront surgery 1.

Management of Pleural Involvement

Pleural metastases from RCC are uncommon but documented 5, 6. The pleural disease may require:

• Symptomatic management: Thoracentesis for symptomatic effusions
• Radiation therapy: Can be used for symptomatic progression of pleural disease 4
• Systemic therapy remains primary: The case of pulmonary/pleural metastases responding to cytoreductive surgery plus interferon 7 predates modern ICI therapy and is not applicable to current practice

Treatment Sequencing

If disease progresses after first-line ICI-based therapy:

• VEGFR-TKIs remain the backbone of subsequent therapy 8, 3
• Options include cabozantinib, axitinib, or lenvatinib + everolimus 2, 8
• ICI rechallenge is not routinely recommended in unselected populations 3
• HIF-2α inhibitors represent emerging later-line options 3

Common Pitfalls to Avoid

1. Do not delay systemic therapy for upfront surgery—this is outdated practice in the ICI era 1
2. Do not underestimate toxicity in adolescents—monitor closely for hypertension, thyroid dysfunction, and immune-related adverse events 4
3. Do not assume adult trial data perfectly translate to adolescents—but limited pediatric data support similar approaches with careful monitoring 4
4. Do not pursue metastasectomy of pleural disease—unlike isolated pulmonary nodules amenable to resection 9, diffuse pleural involvement requires systemic control

Risk Stratification

Determine IMDC risk score based on:

• Time from diagnosis to systemic therapy <1 year
• Karnofsky performance status <80%
• Hemoglobin below lower limit of normal
• Corrected calcium above upper limit of normal
• Neutrophil count above upper limit of normal
• Platelet count above upper limit of normal

This adolescent with pleural metastases likely has intermediate or poor-risk disease, further supporting aggressive systemic therapy over surgical approaches 1, 2.