The tumor and associated cyst size was not correlated to the CXCR4 expression level (95 % confidence interval 298.8; 700.1 mm2 rho = 0.39, P = 0.069 for tumor nodule and 95 % confidence interval 763.7; 1295.5 mm2 rho = 0.095, P = 0.644 for total size; Fig. 5). The gene discussed is CXCR4; the disease is cyst.