Comparing progression of non-functioning pituitary adenomas in hypopituitarism patients with and without long-term GH replacement therapy.

OBJECTIVE: An important safety issue with GH replacement therapy (GHRT) in hypopituitary patients with a history of a pituitary adenoma is the risk for tumour recurrence or enlargement. Design Case-control study. SUBJECTS AND METHODS: We studied tumour progression rate in 121 patients with hypopituitarism on the basis of non-functioning pituitary adenomas (NFPA) receiving long-term GHRT. A group of 114 NFPA patients not receiving GHRT who were matched in terms of duration of follow-up, gender, age, age at diagnosis and radiotherapy status were used as a control population. The average duration of GHRT was 10+/-4 years (range 2-17).
RESULTS: In patients with a known residual adenoma, 63% had no detectable enlargement of tumour during the study. In patients who had no visible residual tumour prior to GHRT, 90% did not suffer from recurrence. In total, the 10-year tumour progression-free survival rate in patients with NFPA receiving GHRT was 74%. In the control population not receiving GHRT, the 10-year progression-free survival rate was 70%. Radiotherapy as part of the initial tumour treatment reduced the rate of tumour progression in both GHRT and non-GHRT patients to a similar extent.
CONCLUSIONS: The rate of tumour progression was similar in this large group of GHRT patients and the control population not receiving GHRT. Our results provide further support that long-term use of GH replacement in hypopituitarism may be considered safe in patients with residual pituitary adenomas.