What are important but rare interferon side effects when used for melanoma?

A few: Interferon used in high dose for adjuvant treatment does have multiple side effects. The uncommon but severe ones include; suicide due to depression, liver damage, severe blood problems. It can be managed by a physician who has experience. Currently a trial compares it to yervoy which takes the breaks off the immune system. It too has side effects, but more promise.

Depression: Number one rare but possible side effect of alfa-interferons for melanoma is severe depression, designated by the fda as a "blackbox warning". Other more rare side effects are worsening or "flares" of pre-existing auto-immune diseases.