The Birmingham pituitary database: auditing the outcome of the treatment of acromegaly

Abstract

BACKGROUND: Reduction of GH concentrations in acromegalic subjects may improve the increased mortality associated with the condition. Audit of the biochemical outcome of the management of acromegaly is, therefore, important. OBJECTIVES: (1) To audit the biochemical 'cure' rate of acromegalic patients treated by surgery and/or radiotherapy under the care of the South Birmingham Endocrine Clinic. (2) To assess the correlation between random or basal GH with IGF-I and nadir GH during an oral glucose tolerance test. DESIGN AND MEASUREMENTS: Ascertainment of acromegalic patients from a pituitary database. Mode of therapy, pretreatment GH, pretreatment tumour size, post-treatment GH, post-treatment IGF-I and post-treatment nadir GH were recorded. Biochemical cure was defined as a most recent random or basal GH < 5 mU/l. Cure rates were determined. PATIENTS: Eighty-nine acromegalic patients were identified as having received surgery and/or radiotherapy. In 35/89 (39%) the most recent GH was < 5 mU/l. The cure rate following surgery was 26/78 (33%). This was not significantly associated with tumour size, but was associated with pretreatment GH concentration (chi 2 = 7.1, 2d.f., P < 0.05). Random/basal GH showed a log-linear association with IGF-I, r = 0.72, and a linear association with nadir GH, r = 0.93. CONCLUSIONS: Biochemical cure of acromegaly was more strongly associated with pretreatment GH than with tumour size. Random/basal GH measurements are useful and convenient for the audit of treatment outcome in acromegaly. Ways of improving the biochemical outcome of acromegaly should be sought.