Trend and Impact of Nephrectomy Centralisation on Renal Cell Carcinoma Survival

Abstract

Introduction The incidence of renal cell carcinoma is increasing worldwide. The widespread use of radiological imaging has contributed to disease stage migration with greater proportion of small, asymptomatic renal tumours often detected incidentally. Despite this, mortality from RCC has not changed substantially and over 4,000 patients still die from RCC in the UK annually, accounting for 3% of all cancer deaths. In response, the Improving Outcomes for Urological Cancers guidance from the National Institute for Health and Care Excellence was published in 2002, recommending the centralisation of oncological resections for urological cancers to high volume centres. During the same period, advancements in surgical technology such as laparoscopic and robotic surgery were emerging together with the adoption of nephron-sparing surgery in the management of small renal tumours.

It is not known how implementation of new guidelines and surgical techniques have impacted on RCC patient outcomes, particularly on a national level. Many population-based studies examining RCC survival have focused on patients irrespective of treatment modality and may include those who have not received active treatment, diluting the true effect of surgical and public health interventions. While evidence has emerged that complex operations performed in high volume centres were more likely to yield better outcomes, it is not yet clear whether this benefit is seen in RCC nephrectomy. There is therefore a need to better understand how RCC nephrectomy has changed in recent years and whether patient outcomes, particularly survival, have improved. Characterisation of the benefit of nephrectomy centralisation is also required particularly as it can significant disrupt patients, clinicians and the wider healthcare system. This study hypothesizes that RCC nephrectomy has undergone substantial changes in recent years with improvements in patient survival. The study also hypothesizes that hospital nephrectomy volume is an important variable in predicting mortality risks both in the post-operative period and in the longer-term.

Methods Information from English patients who underwent RCC nephrectomy between 2000 and 2010 were captured using linked datasets consisted of Hospital Episode Statistics and National Cancer Data Repository. Empirical analyses were performed to examine the temporal trends in RCC nephrectomy practice and outcomes and the relationship between hospital nephrectomy volume and intermediate and long-term patient survival. Meta-analysis was performed to determine the association between hospital nephrectomy volume and perioperative outcomes using studies published between 1990 and 2016.

Results The annual number of RCC nephrectomy performed in England increased by 65.7% during the study period from 2,211 to 3,664. There was rapid adoption of nephron-sparing and minimally-invasive surgery, increasing annually by 13.2% and 54.6% respectively (p<0.01). The number of hospitals performing RCC nephrectomy declined by one quarter but the number of surgeons and nephrectomies performed in each unit steadily increased, suggesting surgical centralisation. In parallel, 30-day mortality decreased from 2.4% to 1.1% (p<0.01). 1 and 5-year age-standardised relative survival increased from 86.9% and 68.2% to 93.4% and 81.2% respectively (p<0.01). Greatest survival improvement was seen in patients with locally advanced disease (T3 or T4).

The improvements could be explained, at least in part, by the centralisation of RCC nephrectomy. Meta-analysis of 12 studies containing 201,506 patients found that patients undergoing radical nephrectomy in high-volume hospitals had a 26% (OR 0.74, 95% CI 0.61- 0.90, p<0.01) reduction in postoperative mortality and 18% (OR 0.82, 95% CI 0.73-0.92, p<0.01) decrease in complications. Similar benefit was observed in nephrectomy with venous thrombectomy where patients treated in high-volume hospitals had a 52% reduction (OR 0.48, 95% CI 0.29-0.81, p<0.01) in postoperative mortality. Survival benefit was also seen beyond the immediate post-operative period. Patients with localised disease treated in high-volume hospitals were 34% less likely to die within the first year (HR 0.66, 95% CI 0.53-0.83, p<0.01). Survival benefit in high-volume hospitals did not appear to extend beyond the first year.

Conclusions During the study period between 2000 and 2010, RCC care in England appears to be improving with factors such as newer surgical techniques and technology contributing to the improvement in patient survival. Nephrectomy centralisation is truly underway with growing evidence that adverse outcomes can be reduced through reconfiguration of surgical delivery.