Spontaneous postoperative normalization of growth hormone levels in two patients with acromegaly not cured by transsphenoidal surgery

Postoperative persistence of elevated growth hormone (GH) levels in patients with acromegaly usually suggests residual adenoma tissue secreting GH and is an indication for further treatment. In rare cases, spontaneous normalization of serum GH levels in patients with acromegaly has been reported to occur as a consequence of intratumoral hemorrhage (pituitary apoplexy). We report two patients in whom persisting acromegaly was documented 1 and 2 weeks, respectively, after transsphenoidal operation and who experienced spontaneous normalization of GH levels. In one patient, this favorable outcome was found 1.5 years after the operation and followed a pregnancy. The other patient, whose GH values normalized 3 months after operation, had received preoperative treatment with a new, long-acting somatostatin analog.