Suprising quotes in the LOTR

[arquenniel]

Forgive me if I'm wrong, but didn't the Silmarillion hint towards Orcs being the twisted forms of elves?

Yet this is held true by the wise of Eressëa, that all those of the Quendi [Elves] who came into the hands of Melkor, ere Utumno was broken, were put there in prison, and by slow arts of cruelty were corrupted and enslaved; and thus did Melkor breed the hideous race of the Orcs in envy and mockery of the Elves, of whom they were afterwards the bitterest foes...

Also, in TTT Saruman says

Do you know how the Orcs first came into being? They were elves once, taken by the dark powers, tortured and mutilated. A ruined and terrible form of life...