Furthermore, as seen in our study, 12 out of 41 patients had positive serological findings, among which, 5 with lymphoid malignancies and membranoproliferative glomerulonephritis presented ANA, whereas, considering the patients with solid tumors, 5 presented PI-GN, histopathologically associated with MPO-ANCA, 1 PI-GN and ANA, and finally 1 lupus-like histopathologic findings and ANA. The gene discussed is MPO; the disease is ganglioneuroma.