Deferred systemic therapy in patients with metastatic renal cell carcinoma

With the advent of small-molecule "targeted" therapies, the prevailing treatment paradigm for metastatic renal cell carcinoma (mRCC) is that all patients who are able to tolerate systemic therapy should receive it. However, oncologists often defer the initiation of systemic therapy for patients with mRCC. The outcomes of and clinical reasoning behind the initial management of patients with mRCC without systemic therapy have not been well described.

We conducted a retrospective cohort study of all patients with mRCC treated within the Duke University Health System and diagnosed from January 1, 2007, to January 1, 2011. We defined our cohort as patients who did not receive systemic therapy during the first year after mRCC diagnosis. The clinical rationale for the lack of immediate treatment was ascertained by manual chart review.

A total of 60 of 268 patients (22%) with mRCC managed without initial systemic therapy were included in our study. The median age was 61.2 years, the median duration from diagnosis of localized RCC to development of mRCC was 41.9 months, and 91% of patients had Eastern Cooperative Oncology Group functional status of ≤ 1. Of the patients, 60% were managed with surgical metastasectomy alone, 12% received multiple local treatment modalities, 13% received active surveillance, 7% were managed supportively, and 8% were categorized as "other."

The majority of patients in our cohort had favorable disease characteristics and experienced favorable outcomes with surgery alone. Our results suggest that this population could represent 20% of patients with mRCC in tertiary care settings. Prospective data are needed to evaluate deferred systemic therapy as a management strategy.