IFNA1 and lymphoma: Although a significant excess of plasma cell neoplasms and lymphoma was reported (O/E, 13.04; p < 0.001 and O/E, 8.7; p = 0.03, respectively), an excess of second neoplasms specifically related to a single drug was not detected (IFN, p = 0.27; cladribine, p = 0.37; pentostatin, p = 0.7).