ADA and neoplasm: The results showed that ADA activity was significantly increased in patients with fever (44.39 ± 25.13 vs 12.47 ± 5.97, p = 0.0017), skin rash (46.95 ± 25.77 vs 24.51 ± 18.78, p = 0.0029), splenomegaly (51.30 ± 30.15 vs 32.87 ± 19.96, p = 0.01), pleuritis (56.62 ± 30.75 vs 35.86 ± 22.96, p = 0.016), and pericarditis (56.59 ± 27.73 vs 35.37 ± 23.55, p = 0.01) (Fig. 4a–e).