IFNA1 and cancer: In a recent retrospective cohort study of 184 patients with G2 SI-NETs treated with SSAs, interferon-alpha (IFN), or PRRT [45], the authors reported that baseline 24u5HIAA was associated with cancer-specific survival (CSS) following treatment with IFN and PRRT, yet not for SSA treatment alone and that it was a statistically significant prognostic marker of progression free-survival (PFS) for patients treated with PRRT.