Early postoperative growth hormone levels: high predictive value for long‐term outcome after surgery for acromegaly

• Published in: Journal of internal medicine Vol. 247; no. 6; pp. 640 - 650
• Main Authors: Valdemarsson, S., Ljunggren, S., Bramnert, M., Norrhamn, O., Nordström, C. H.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Science Ltd 01.06.2000; Blackwell Science; Blackwell Publishing Ltd
• Subjects: acromegaly; Acromegaly - blood; Acromegaly - surgery; Adult; Aged; Aged, 80 and over; Biological and medical sciences; Female; Follow-Up Studies; growth hormone; Human Growth Hormone - blood; Humans; IGF‐1; Insulin-Like Growth Factor I - metabolism; Male; Medical sciences; Middle Aged; pituitary; pituitary tumour; Postoperative Period; Predictive Value of Tests; Recurrence; Retrospective Studies; Sensitivity and Specificity; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Surgery of endocrine glands; Time Factors; transsphenoidal surgery; Endocrinopathy; Short term; Human; Postoperative; Evaluation; Prognosis; Diseases of the osteoarticular system; Somatotropin hormone; Acromegaly; Long term; Result; Protein hormone; Comparison measurement; Adenohypophyseal hormone; Pituitary diseases; Early; Predictive factor
• ISSN: 0954-6820; 1365-2796
• DOI: 10.1046/j.1365-2796.2000.00667.x

. Valdemarsson S, Ljunggren S, Bramnert M, Norrhamn O, Nordström CH (Lund University Hospital, Lund, and Malmö University Hospital, Malmö, Sweden). Early postoperative growth hormone levels: high predictive value for long‐term outcome after surgery for acromegaly. J Intern Med 2000; 247: 640–650. Objectives. To explore the prognostic value of early – within 1 week – postoperative growth hormone (GH) measurements with regard to outcome after surgery for acromegaly in a short‐ and a long‐term perspective. Design. Retrospective study of patients operated on between 1987 and 1998, including follow‐up for up to 60 months. Setting. University hospital. Subjects. Sixty‐eight patients with acromegaly. Intervention. Pituitary surgery aiming at adenomectomy with preservation of pituitary function. Main outcome measures. The effect of the operation was evaluated after 3 months, mostly by means of an oral glucose load or by insulin‐like growth factor 1 (IGF‐1). The specificity, sensitivity and the predictive values of an early postoperative mean GH concentration ≤ 4.8 mU L–1, as well as of the GH response to thyrotropin‐releasing hormone (TRH) 3 months after surgery, were calculated with regard to outcome of the operation in both 3‐month and long‐term perspectives. Results. Fifty patients (73.5%) showed a satisfactory effect at the evaluation 3 months postoperatively; 45 of these were followed between 12 and 60 months. Relapse was registered in five cases: 12, 12, 24, 24 and 48 months after surgery. In the long‐term perspective, the predictive value of an early mean GH ≤ 4.8 mU L–1 was 93.6% with regard to a satisfactory effect of surgery, compared with 90.2% for a normalized somatomedin C (SmC)/IGF‐1 and 90.0% for an absent GH response after TRH. An early mean GH > 4.8 mU L–1 had a 77.8% predictive value for persistent or recurrent disease, compared with 85.7% for persistently increased SmC/IGF‐1 and 68.8% for an abnormal GH release after TRH 3 months after surgery. In the short‐term perspective, the specificity and the predictive value of an early GH ≤ 4.8 mU L–1 were 77.3 and 97.1%, respectively. Early GH > 4.8 mU L–1 had a 94.4% sensitivity but a predicative value of only 63.0% for an unsatisfactory effect. Conclusion. Measurement of GH within 1 week after surgery is highly predictive for outcome of surgery for acromegaly. Specifically, an early mean GH ≤ 4.8 mU L–1 is as predictive for a satisfactory effect of treatment as a normalized IGF‐1 3 months after surgery. Early postoperative GH values > 4.8 mU L–1 have a high sensitivity for persistent or recurrent disease in both the short‐ and long‐term perspectives, but lower predictive value. The usefulness of the TRH test can be questioned.