Comparative study on clinicopathological characteristics of functional and non-functional subtypes in pituitary adenomas

Abstract

Background Pituitary adenomas comprise clinical and pathological characteristics of functional and non-functional subtypes. To enhance our understanding of diagnostic presentations, our study aimed to know the clinicopathological characteristics of pituitary adenomas of both functional and non-functional subtypes. The purpose of our study was to investigate the clinicopathological characteristics of pituitary adenomas, including demographic characteristics, clinical presentations, hormone secretion patterns, invasiveness, and cellular characteristics. Methods A total of 41 cases of pituitary adenomas were analyzed, with 63.4% classified as non-functional adenomas (NFPA) and 36.6% as functional adenomas (FPA). Clinical presentations vary, with vision loss and headaches commonly occurring in both NFPA and FPA. In FPAs, serum hormone levels varied and were categorized into growth hormone-secreting (53.3%), ACTH-secreting (26.7%), PRL-secreting (13.3%), and FSH-secreting (6.7%) subtypes. Moreover, clinical presentations in FPA included diplopia, giddiness, vomiting, ptosis, and limb weakness. Clinical features varied across subtypes, with acromegaly in growth hormone-secreting adenomas, moon facies and weight gain in ACTH-secreting adenomas, poor facial growth in PRL-secreting adenomas, and vision loss in FSH-secreting adenomas. Meanwhile, NFPA were predominantly macroadenomas (88.5%) and exhibited various morphological patterns. Results The proliferation index is higher in functional adenomas (mean 1.32) as compared to non-functional (mean 0.91). Clinical presentations varied across functional and non-functional adenomas. Growth hormone-secreting adenomas were the most common functional subtype, while LH and null cell adenomas were common non-functional subtypes. Two cases were invasive adenomas with a low Ki67 index. Sheets were the most common morphological pattern. PCA analysis revealed significant differences between the two groups, with PC 1 explaining 92.111% of the variance. Conclusions Our study elucidates the clinicopathological characteristics of pituitary adenomas, highlighting significant differences between functional and non-functional subtypes. These findings underscore the importance of tailored diagnostic and management strategies to optimize outcomes for patients with pituitary adenomas.