Purpose: Several studies have shown that cystatin C levels can be used to detect decline in renal function in cancer patients receiving chemotherapy, and can serve as a supplement to creatinine level measurement for early detection of renal insufficiency. Nevertheless, use of the parameter remains controversial. This study aimed to assess the value of serum cystatin C levels in evaluation of early renal insufficiency due to chemotherapy.
Methods: Studies were retrieved from PubMed, Ovid Embase, the Web of Science, the Cochrane Library, Ovid, and the CNKI databases up to May 15, 2018. Serum levels of cystatin C before and after chemotherapy were evaluated for its ability to assess renal function.
Results: A total of 12 studies, including 1775 participants, met our inclusion and exclusion criteria. Pooled analysis revealed that the levels of serum cystatin C in cancer patients after chemotherapy were significantly higher than those of patients prior to treatment [standard mean difference (SMD) = 0.54, 95% CI 0.34-0.74, P = 0.0000]. Compared to creatinine, serum cystatin C increased significantly in the early phases of glomerular filtration rate (GFR) change before and after chemotherapy (GFR ≥ 90 ml/min/1.73 m2, P < 0.05 vs. P > 0.05, 5.83%; 60 < GFR < 90 ml/min/1.73 m2, P < 0.01 vs. P > 0.01, 38.83%) and increased more substantially in the later phases (GFR < 60 ml/min/1.73 m2, P < 0.01 vs. P < 0.01, 70.87% vs. 23.09%). However, creatinine decreased even in the early phases and did not increase in an obvious manner until the later phases (GFR < 60 ml/min/1.73 m2, P < 0.01, 23.09%). The GFR values were derived from measured methods.
Conclusions: Cystatin C may be superior to creatinine for the detection of minor changes in GFR in early stages of renal insufficiency secondary to chemotherapy. More studies are needed to further verify this result.
Keywords: Chemotherapy; Cystatin C; Meta-analysis; Renal insufficiency.