An arithmetic read-once formula (ROF for short) is a formula (a circuit whose underlying graph is a tree) in which the operations are {+, ×} and such that every input variable labels at most one leaf. A preprocessed ROF (PROF for short) is a ROF in which we are allowed to replace each variable xi with a univariate polynomial Ti(xi). In this paper we study the problems of giving deterministic identity testing and reconstruction algorithms for preprocessed ROFs. In particular we obtain the following results.