chest wall vs dirty pillow

chest wall

noun
  • The set of tissues that bound the thoracic cavity, including the rib cage, fascia, muscles etc. 

dirty pillow

noun
  • A breast, especially a woman's breast. 

  • Used other than figuratively or idiomatically: see dirty, pillow. 

How often have the words chest wall and dirty pillow occurred in a corpus of books? (source: Google Ngram Viewer )