Significance of thrombocytosis for determining prognosis in patients with localized renal cell carcinoma.

OBJECTIVES

To evaluate the significance of thrombocytosis for determining survival in patients with localized renal cell carcinoma (RCC) who underwent radical nephrectomy with curative intent.

METHODS

The study population comprised 151 patients who underwent radical nephrectomy with a diagnosis of localized RCC. The inclusion criteria were at least one preoperative platelet count and a tissue diagnosis of RCC. Thrombocytosis was defined as a platelet count greater than 400,000/mm3. The charts of these patients were retrospectively reviewed and the relationship between the preoperative platelet counts and survival was evaluated according to the histologic variants.

RESULTS

The mean follow-up was 37.1 +/- 24.1 months (median 34, range 3 to 91). Of these 151 patients, 21 had a preoperative platelet count greater than 400,000/mm3. The thrombocytosis rate was significantly greater in those with advanced T stage (P = 0.045). Lymph node positivity also correlated with thrombocytosis (P = 0.028). However, no statistically significant correlation was found between grade and histologic subtypes and thrombocytosis (P = 0.053 and P = 0.354, respectively). Ten (47.6%) of 21 patients with thrombocytosis and 21 (16.2%) of the remaining 130 patients died of disease progression (P = 0.002). The Kaplan-Meier cause-specific survival curves showed that patients who had thrombocytosis had a mean survival of 45.2 months compared with 76.6 months in patients without thrombocytosis (P = 0.0002).

CONCLUSIONS

Preoperative thrombocytosis is a significant predictor for determining prognosis in patients with localized RCC. Thrombocytosis was found more frequently in patients with advanced stage RCC, and patients with preoperative thrombocytosis had a worse survival compared with those with normal platelet counts.