Object: The authors evaluated the pathological and clinical characteristics of young patients with clinically nonfunctioning pituitary adenomas (NFPAs).
Methods: Twenty-one patients (13 males and 8 females) with NFPAs who were 25 years of age or younger (mean 20 years, range 13-25 years) were retrospectively investigated. The following factors were examined: results of conventional light microscopy, immunohistochemistry, and electron microscopy; clinical symptoms; tumor size and invasion on MRI; and clinical course after therapeutic procedures such as surgery and adjuvant radiotherapy.
Results: Two major significant findings in young patients with NFPAs were noted. First, silent subtype 3 adenomas were common, whereas silent gonadotroph adenomas were rare. Second, silent subtype 3 adenomas in young patients tended to be clinically and radiologically aggressive.
Conclusions: To correct the morphological diagnosis, NFPAs in young patients should be examined by immunohistochemical analysis and electron microscopy, as well as by light microscopy. The authors' results provide information that will be useful when making decisions regarding the treatment of young patients with NFPAs.