Results of lymph node dissection for locally advanced and metastatic renal cell carcinoma

Retroperitoneal lymph node dissection (RPLND) at the time of nephrectomy for renal cell carcinoma (RCC) is controversial. Moreover, it is difficult to determine preoperatively those who will benefit from RPLND. The objective of this study is to describe RPLND outcomes at the time of radical nephrectomy in advanced RCC.

Locally advanced and metastatic RCC patients treated with radical nephrectomy and RPLND from June 2016 to July 2017 were included. Common preoperative clinical and pathological variables were collected to identify associations with high risk disease. Presence of four radiographic variables were assessed preoperatively to determine an RPLND at the time of radical nephrectomy. These included tumor size > 10cm, lymphadenopathy (LN > 1 cm diameter in short axis), tumor necrosis (defined as low-enhanced tumor areas), and distant metastases.

Twenty-eight patients who underwent a radical nephrectomy and RPLND were available for study review. There were 17 males and 11 females included with a median age of 61 (IQR 55-68). Twenty-two patients (79%) had clinical stage 3 or higher disease. Median number of lymph nodes removed during RPLND was 13 (IQR 12-27). Median number of positive lymph nodes was 3.6 (IQR 1-5.5). Lymph node positive RCC was diagnosed in 6 (21%) patients. Of the patients who had radiographic lymphadenopathy, 6 of 10 (60%) had lymph node positive disease. Metastatic RCC was diagnosed in 8 patients who underwent cytoreductive nephrectomy. Of these patients, 4 (50%) demonstrated positive lymph nodes following RPLND.

Differences between lymph node positive patients and lymph node negative patients were assessed according to the presence of four radiographic criteria as demonstrated on cross-sectional imaging. Of the 6 lymph node positive patients, all had ≥3 criteria compared to just 2 patients with lymph node negative disease (p<0.0001; Fisher’s exact).

In high risk patients with advanced RCC, RPLND may be considered during radical nephrectomy for complete staging and potential enrollment into adjuvant systemic therapy trials. Preoperative assessment of high risk features is important to determine who will ultimately benefit from RPLND.