Results of endoscopic transsphenoidal pituitary surgery in 40 patients with a growth hormone-secreting macroadenoma.

OBJECTIVE: Transsphenoidal pituitary surgery (TS) is the primary treatment of choice for patients with acromegaly. Macroadenomas (>1 cm) are more difficult to resect than microadenomas (remission rate ± 50% compared to ± 90%). Besides the conventional microscopic TS, the more recently introduced endoscopic technique is nowadays frequently used. However, no large series reporting on its results have yet been published. We evaluated the outcome of endoscopic TS in 40 patients with a growth hormone (GH)-secreting macroadenoma treated in our hospital between 1998 and 2007. METHODS: Medical records were retrospectively reviewed. Remission was defined as disappearance of clinical symptoms of acromegaly, normal serum insulin-like growth factor-1 levels (≤2 SD) and serum GH levels suppressed to <2 mU/l after an oral glucose tolerance test within the first 4 months after TS. RESULTS: In four patients TS aimed at debulking of the tumour. In the remaining 36 patients, remission was achieved in 20 patients. In the first 5 years remission was achieved in 6 out of 18 patients (33%) compared to 14 out of 22 patients (63%) in the following 5 years (p = 0.06). Thirteen patients had a mild perioperative complication. Before TS 15 patients received hormonal substitution therapy compared to 12 patients (33%) after TS. CONCLUSION: Endoscopic TS is a good primary therapeutic option for patients with a GH-secreting macroadenoma, resulting in a remission rate of up to 63% in experienced hands. This technique can potentially improve the outcome of TS in these patients.

Cetrorelix suppression test in the diagnostic work-up of severe hyperandrogenism in adolescence.

UNLABELLED: Conventional diagnostic procedures failed to provide a definitive diagnosis in a 15 year-old girl presenting with severe hirsutism, oligomenorrhea, and markedly elevated serum testosterone levels. To examine whether androgen overproduction was luteinizing hormone (LH) dependent and thus likely of ovarian origin we performed a new test to suppress LH secretion based on the use of Cetrorelix, a short-acting gonadotropin-releasing hormone antagonist. Subcutaneous administration of Cetrorelix 250 microg once daily for 5 days resulted in partial suppression of serum LH and testosterone. The same dose administered twice daily for 5 days almost completely suppressed serum LH and testosterone, thereby supporting a diagnosis of ovarian androgen excess. This observation was confirmed by a positive human chorionic gonadotropin stimulation test and an MRI showing bilateral polycystic ovaries. CONCLUSION: The Cetrorelix suppression test appears to be a promising instrument to help solve the differential diagnosis of severe hyperandrogenism in adolescence.

18F-FDG PET reduces unnecessary hemithyroidectomies for thyroid nodules with inconclusive cytologic results.

UNLABELLED: Fine-needle aspiration biopsy (FNAB) is inconclusive in up to 20% of patients with solitary thyroid nodules. In these cases, hemithyroidectomy is necessary, but only 20% of the nodules prove to be thyroid carcinoma. The aim of this study was to explore the potential of (18)F-FDG PET to reduce the number of unnecessary hemithyroidectomies in the preoperative assessment of thyroid nodules with inconclusive FNAB results. METHODS: Forty-four consecutive patients, scheduled for hemithyroidectomy because of inconclusive FNAB findings, participated in this prospective study. (18)F-FDG PET of the thyroid region was performed before hemithyroidectomy, and standardized uptake values were calculated. The final histopathologic diagnosis served as a standard of reference. RESULTS: Histopathologic examination of the surgical specimens revealed 7 well-differentiated thyroid carcinomas in 6 patients, all accumulating (18)F-FDG (negative predictive value, 100%). (18)F-FDG accumulated in 13 of 38 benign nodules. The pre-PET probability for cancer in this study population was 14% (6/44), and the post-PET probability increased to 32% (6/19). The percentage of unnecessary hemithyroidectomies in a hypothetical algorithm using (18)F-FDG PET was only 30% (13/44), compared with 86% (38/44) without (18)F-FDG PET. (18)F-FDG PET reduced the number of futile hemithyroidectomies by 66% (25/38) (95% confidence interval, 49%-80%; Fisher's exact test, P = 0.0038). Semiquantitative analysis using standardized uptake values did not help to further reduce this number. CONCLUSION: In addition to data in the literature demonstrating accurate detection of thyroid cancer by (18)F-FDG PET, this study showed that (18)F-FDG PET should play an important role in the management of patients with inconclusive cytologic diagnosis of a thyroid nodule. (18)F-FDG PET reduced the number of futile hemithyroidectomies by 66%. Although PET is a relatively costly procedure, this cost outweighs the costs and risks associated with unnecessary thyroid surgery.