Therefore, although the nature of nephritis is possibly associated with poor immune complex activity in delayed‐onset LN, it was considered that the reason serum albumin and C3 levels were high in delayed‐onset LN patients was that the immune complex activity of SLE improved following prior treatments, as suggested by the lower SLEDAI‐2K score in the delayed‐onset LN patients. Here, C3 is linked to lobular neoplasia.