Introduction

Many previous reports have shown an increased risk of cancer recurrence in oncological patients receiving blood transfusions at surgery. In renal cell carcinoma (RCC), it has been postulated that blood transfusion might impact the immunosuppressive response with a subsequent decreased host-tumor surveillance. We aimed to evaluate if intraoperative blood transfusion (IBT) may be associated with cancer specific mortality (CSM) and overall mortality (OM) in RCC candidates to surgical treatment.

Methods

We evaluated 2,528 consecutive patients diagnosed with RCC and treated with partial or radical nephrectomy between 1987 and 2011. IBT was defined as transfusion of allogenic red blood cells during surgery. Univariable and multivariable Cox proportional hazards regression analyses were used to predict CSM and OM. Covariates included age at surgery, gender, pathological T stage, pathological N stage, pathological grade, lymph vascular invasion, tumor size, Charlson Comorbidity Index (CCI), year of surgery, symptoms at the presentation and tumor necrosis. Preoperative hemoglobin and bleeding were also included in a second model to test the independent effect of IBT on the outcomes of interest.

Results

Overall, 784 patients out of 2,528 (31%) received IBT. In those patients, the median number of units transfused was 3 (range 1-7). Patients receiving IBT were significantly older (median age 61 vs. 64, p<0.001), with higher CCI (median CCI 5% vs. 8%, p<0.001), more symptomatic (35% vs 50%, p<0.001) and with more advanced pathological characteristics, such as high grade (Fuhrman 3-4: 25% vs. 43%, p<0.001), tumor stage (pT3-4 17% vs. 45%, p<0.001) and lymph node invasion (pN1: 4 % vs. 14%, p<0.001). Median follow-up was 72 months (IQR 10-90). Receipt of IBT was associated with CSM (HR 3.15 95%CI: 2.54-3.92, p<0.001) and OM (HR 2.40 95%CI: 2.07-2.78, p<0.001). At multivariate analyses, IBT was associated with higher risk of OM (Hazard ratio [HR] 1.09; [CI] 1.006-1.192; p<0.05). Among patients who received IBT, an increasing number of units transfused was independently associated with increased OM (HR 1.14 [CI] 1.05-1.21; p< 0.05).

Conclusions

When observing long-term follow-up, IBT is associated with a significantly increased risk of both CSM and OM after nephrectomy. Further investigations are needed to fully understand the impact of blood transfusions on RCC and the pathological mechanisms which can be modified by adequate intraoperative and post-operative patient management.

Funding

None