benignancy vs malignity

benignancy

noun
  • benignity 

malignity

noun
  • The quality of being malign or malignant; badness, evilness, monstrosity, depravity, maliciousness. 

  • A non-benign cancer; a malignancy. 

How often have the words benignancy and malignity occurred in a corpus of books? (source: Google Ngram Viewer )