Metastatic Renal-Cell Carcinoma: Active Surveillance Feasible For Select Metastatic Renal-Cell Carcinoma Patients

Active Surveillance Feasible For Select Metastatic Renal-Cell Carcinoma Patients
Regular imaging may allow some renal-cell carcinoma patients with asymptomatic metastases to delay initiation of systemic treatment

Date: 04 Aug 2016
Author: By Lynda Williams, Senior medwireNews Reporter
Topic: Renal Cell Cancer

medwireNews: Active surveillance may be an option for asymptomatic patients with metastatic renal-cell carcinoma, suggest study findings published in The Lancet Oncology that indicate systemic therapy may be safely delayed in carefully selected cases.

The phase II trial performed at five hospitals in the USA, Spain and the UK monitored treatment-naive patients using computed tomography scans of the chest, abdomen and pelvis at baseline, every 3 months for the first year, every 4 months for the second year and at 6-month intervals thereafter.

In all, 48 of the 52 patients who were enrolled in the study were followed up for a median of 38.1 months. Active surveillance continued until the patient and physician chose to initiate systemic chemotherapy, which occurred after a median of 14.9 months.

RECIST-defined progression was reported in 90% of the patients after a median of 9.4 months, with 37 patients beginning systemic therapy and six continuing with surveillance for a further 15.8 months.

Symptomatic disease occurred in just two patients during surveillance, both of whom developed new sites of central nervous system metastases, prompting the authors to suggest routine neurological imaging during surveillance.

Exploratory analysis gave a median 12-month progression-free survival (PFS) rate of 41%, with 22%, 17% and 11% of patients still free from progression at 18, 24 and 36 months, respectively. Median overall survival from the start of surveillance was estimated to be 44.5 months.

Multivariate analysis showed that length of surveillance was significantly and independently predicted by number of involved organs and the number of International Metastatic Database Consortium (IMDC) risk factors.

Indeed, patients could be divided into two prognostic groups, such that the 60% of patients with up to two affected organs and no more than one IMDC risk factor achieved a significantly longer median surveillance time than the remaining patients with more affected organs and IMDC risk factors, at 22.2 versus 8.4 months.

“The present data should be interpreted in light of other therapeutic options in this disease”, write Brian Rini, from the Cleveland Clinic Taussig Cancer Institute in Ohio, USA, and co-investigators.

They say that their study patients had an “identical” 3-year PFS rate to that achieved in a trial of high-dose interleukin-2 and comparable clinical outcomes to a phase III trial comparing sunitinib versus pazopanib in patients with good- and intermediate-risk disease, albeit “with the important caveat that patients enrolled on our trial were highly selected and no direct comparison can be drawn for long-term survival.”

The authors conclude: “Taken together with published retrospective data, our findings show that select patients with metastatic renal-cell carcinoma can have prolonged time to cancer progression with surveillance prior to initiating systemic therapy.

“Additional experience is necessary to understand the risks and benefits of this approach.”

The author of an accompanying comment agrees: “This paper provides guidance to both medical and surgical oncologists who, when faced with a newly diagnosed patient with metastatic renal-cell carcinoma who has good performance status and limited metastatic disease, can offer a period of close surveillance with the potential for prolonged survival before disease progression and the initiation of systemic therapies.”

Paul Russo, from Memorial Sloan Kettering Cancer Center in New York, USA, concludes: “There is no evidence from this study that such a period of close surveillance jeopardises the patient’s safety or survival.”

References

Rini BI, Dorff TB, Rodriguez CS, et al. Active surveillance in metastatic renal-cell carcinoma: a propsective, phase 2 trial. Lancet Oncol 2016; Advance online publication 3 August. DOI: http://dx.doi.org/10.1016/S1470-2045(16)30196-6

Russo P. Delayed systemic treatment in metastatic renal-cell carcinoma. Lancet Oncol 2016; Advance online publication 3 August. DOI: http://dx.doi.org/10.1016/S1470-2045(16)30247-9