Spontaneous regression of multiple pulmonary metastases accompanied by normalization of serum immune markers following cytoreductive nephrectomy in a patient with clear-cell renal cell carcinoma

Spontaneous regression of choroidal metastasis from renal cell carcinoma

Purpose

To report a case of an elderly man who presented with a choroidal metastasis from renal cell carcinoma that spontaneously regressed prior to any local or systemic treatment.

Observations

An 82-year-old man without a history of metastatic cancer was referred to the ocular oncology service for evaluation of a newly noted amelanotic choroidal lesion. Examination and imaging findings were concerning for choroidal metastasis. Systemic workup revealed previously undiagnosed widely metastatic renal cell carcinoma. The lesion spontaneously regressed prior to the initiation of any treatment for his tumor.

Conclusions and importance

This is a unique case of choroidal metastases from renal cell carcinoma that spontaneously regressed prior to medical or surgical treatment of the primary tumor.

Role of Surgery in Metastatic Renal Cell Carcinoma

Surgery has historically been the mainstay of treatment for metastatic renal cell carcinoma (mRCC), but recent clinical trials demonstrated that contemporary systemic therapies alone are non-inferior to cytoreductive nephrectomy (CN). Thus, the current role of surgery is not precisely defined. CN remains an appropriate upfront treatment for the palliation of severe symptoms, select cases of metastatic non-clear cell renal cell carcinoma, for consolidation following systemic therapy, and in the setting of oligometastatic disease. Metastasectomy is ideally utilized to achieve a disease-free state when there is minimal morbidity associated with surgery. Given the heterogenous nature of mRCC, the decision for systemic therapy and surgery should be made through a multidisciplinary approach tailored to each individual patient.

Adjuvant therapy options in renal cell carcinoma - targeting the metastatic cascade

Localized renal cell carcinoma (RCC) is primarily managed with nephrectomy, which is performed with curative intent. However, disease recurs in ~20% of patients. Treatment with adjuvant therapies is used after surgery with the intention of curing additional patients by disrupting the establishment, maturation or survival of micrometastases, processes collectively referred to as the metastatic cascade. Immune checkpoint inhibitors and vascular endothelial growth factor receptor (VEGFR)-targeting tyrosine kinase inhibitors (TKIs) have shown efficacy in the treatment of metastatic RCC, increasing the interest in the utility of these agents in the adjuvant setting. Pembrolizumab, an inhibitor of the immune checkpoint PD1, is now approved by the FDA and is under review by European regulatory agencies for the adjuvant treatment of patients with localized resected clear cell RCC based on the results of the KEYNOTE-564 trial. However, the optimal use of immunotherapy and VEGFR-targeting TKIs for adjuvant treatment of RCC is not completely understood. These agents disrupt the metastatic cascade at multiple steps, providing biological rationale for further investigating the applications of these therapeutics in the adjuvant setting. Clinical trials to evaluate adjuvant therapeutics in RCC are ongoing, and clinical considerations must guide the practical use of immunotherapy and TKI agents for the adjuvant treatment of localized resected RCC.

Combinations of Anti-Angiogenic Agents and Immune Checkpoint Inhibitors in Renal Cell Carcinoma: Best Option?

Over the past decade, major advances have been made in the treatment of advanced and metastatic renal cell carcinomas, specifically clear cell carcinomas. For many years the optimal approach was sequential; thus, monotherapies [principally tyrosine kinase inhibitors (TKIs)] targeting angiogenesis until toxicity or progressive disease developed. The rationale was the common mechanisms of action of the targeting agents and avoidance of the risk of overlapping toxicities. Immune checkpoint inhibitors (ICIs) are effective monotherapies, and combinations thereof with anti-angiogenic agents were thus later considered. Synergistic interactions were reported in vitro. Clinical efficacy was evident in three pivotal phase III trials with axitinib-pembrolizumab, cabozantinib-nivolumab, and lenvatinib-pembrolizumab combinations. Two other combinations showed interesting results but did not improve overall survival. However, the data aided our understanding of the new therapeutic approaches. A combination of the ICIs nivolumab and ipilimumab was the first to evidence better progression-free and overall survival compared to sunitinib in patients with intermediate or unfavourable prognoses as evaluated by the International mRCC Database Consortium (IMDC). Here we focus on the TKI-ICI combinations, emphasising the rationale of their use and the clinical results. To date, no biomarker facilitating the selection of an optimal treatment by disease and patient status has been reported.