Clinical Characteristics and Postoperative Recovery of Hypopituitarism in Patients with Nonfunctional Pituitary Adenoma

Abstract

To investigate the clinical characteristics of hypopituitarism and its reversibility after surgery for nonfunctional pituitary adenoma (NFPA); analyze the correlation between tumor size and hypopituitarism incidence; and predict hypopituitarism by tumor volume and maximum diameter. We retrospectively reviewed 164 patients with NFPA who underwent surgical treatment at Peking Union Medical College Hospital from January 2016 to December 2016. Demographic, imaging, and endocrine data were collected during preoperative, postoperative, and long-term follow-up (21.1 ± 3.3 months) periods. Differences in hormone levels were analyzed by paired and independent samples t-tests. The cut-off values of tumor size and volume to predict hypopituitarism were calculated by receiver operating characteristic curves. In total, 80.4% (132/164) of patients had anterior pituitary hypofunction and 48.4% patients had hypogonadism; the recovery rate of luteinizing hormone was 80.9%, and follicular-stimulating hormone was 60%. In total, 36.5% of patients had hypothyroidism; the recovery rate of thyroxine was 85%, free thyroxine was 87.8%, and thyroid-stimulating hormone was 100.0%. Finally, 27.4% of patients had insulin-like growth factor 1 (IGF-1)/growth hormone (GH) hypofunction, and the recovery rate of IGF-1 was 77.8%. The preoperative free thyroxine, thyroxine, GH, IGF-1, follicular-stimulating hormone, and luteinizing hormone levels were significantly lower in the giant adenoma group (n= 43) than in the large adenoma group (n= 121). The hypopituitarism predictive cut-off value of tumorvolume was 3105.1 mm3 and that of tumor diameter was 23.5 mm. NFPA has a significant influence on gonadal hormone, IGF-1/GH, and thyroid hormone. NFPA can cause single- or multiple-hormone reduction in each pituitary target gland. Tumor size is positively correlated with the incidence and degree of hypopituitarism. NFPA-induced hypopituitarism is significantly recovered after surgical treatment.