Recurrence in pituitary adenomas in childhood and adolescence

Pediatric pituitary adenomas are thought to behave more aggressively than their adult counterparts, and the ability to predict the degree of such behavior remains elusive. Proliferation marker Ki-67 and tumor suppressor gene p53 mutations have been used in adults to assist in the evaluation of invasiveness and recurrence; however, their use in childhood and adolescence remains anecdotal. Our study evaluates the proliferative potential in pituitary adenomas of five patients and its relationship with recurrence or persistence of endocrinologic or clinical abnormalities. For such assessment, tissues were stained with monoclonal antibodies BP53-12 forp53 tumor suppressor gene mutation and MIB-1, which binds to cell cycle-specific nuclear antigen Ki-67. In our series, one patient with recurrent adenoma demonstrated the highest (50%) p53 immunoreactivity. Ki-67-stained nuclei ranged from 0 to 2%, failing to identify the recurrent tumor. Therefore, p53 immunoreactivity, rather than Ki-67 nuclear stain, may be useful for identification of recurrent pituitary adenomas in childhood and adolescence.