C4A and lobular neoplasia: Statistically significant differences were found between the active LN and the non-active LN groups regarding the serum albumin level (mean ± SD 2.4 ± 0.5 vs 3.6 ± 0.3), C3 (mean ± SD 55.1 ± 24.8 vs 90.0 ± 21.0), and C4 (mean ± SD 9.0 ± 5.5 vs 21.3 ± 8.7).