Thrombocytosis as a prognostic factor in patients with renal cell carcinoma: a meta-analysis of literature.

BACKGROUND

The aim of this study was to analyze the prognostic implications of perioperative thrombocytosis in patients with renal cell carcinoma (RCC).

MATERIALS AND METHODS

We conducted search on two medical databases, PubMed and EMBASE, to identify all studies. A meta-analysis was performed to clarify the prognostic role of thrombocytosis.

RESULTS

Twelve studies (N = 8735) were included which evaluated the relation of thrombocytosis and 5-year overall survival (OS) or cancer-specific survival (CSS). One thousand and fifty-nine (12.1%) of the 8735 patients exhibited thrombocytosis, and for OS, their estimated risk of death in 5 years was 1.61-fold higher compared with the normal platelet count group [(RR = 1.61, 95% CI = (1.31-1.98), P < 0.001)]. While for CSS, the mortality was 2.56-fold higher [(RR = 2.56, 95% CI = (1.73-3.80), P < 0.00001). According to subgroup analyses, significant positive influence of thrombocytosis on 5-year OS and CSS was displayed only in patients with localized RCC and was also found in patients originated from different areas, such as Asian, Europe or North American.

CONCLUSIONS

Thrombocytosis indicates worse OS and CSS for patients with RCC, and it showed stronger specificity or sensitivity for CSS. Thrombocytosis is more frequently in patients with metastatic RCC but only showed significant influence on survival of localized RCC patients.