Difference in Pituitary Cyst Volumes Between Patients with Growth Hormone Deficiency and Idiopathic Short Stature

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: SAT 164-196-Pituitary
Basic/Clinical
Saturday, June 15, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board SAT-165
Richard A Noto*, Shrinkhala Srivastava, Shana Flicker, Kyle Reynolds, Brad Pogostin, Michael Tenner, Qiuhu Shi and Michael Frey
New York Medical College, Valhalla, NY
Background: We have previously shown that the incidence of pituitary cysts in short children is not different from what is found in autopsy findings and it is felt to be a benign condition.  Objectives: In this study, we further analyzed actual cyst volume and if there was a difference in cyst volume or percentage of the pituitary gland occupied between Growth Hormone Deficient (GHD) and Idiopathic Short Stature (ISS) patients.  Subjects: Brain MRIs of 618 GHD and ISS patients were reviewed. From this group, 56 patients (36 GHD, 20 ISS) were found to have a pituitary cyst.  Methods: MRI imaging with post-gadolinium contrast with particular attention to the pituitary gland in patients with GHD and ISS was analyzed for the presence of cysts, volume, and percentage of pituitary gland occupied.  Results: An MRI review of 56 patients showed a pituitary cyst incidence of 9.1% for all patients with 9.9% for males and 7.6% for females. Cyst analysis showed a significant difference between cyst volume in GHD (mean 62.0mm3±67.2, median 48.9) and ISS patients (mean 29.4mm3±38.4, median 16.5) (p=0.0111). For males, the difference between cyst volume between GHD patients (mean 68.9mm3±74.9, median 53.7) and ISS patients (mean 29.5mm3±46.7, median 14.5) was significant (p=0.0253). For females, the difference between cyst volume between GHD patients (mean 41.3mm3±29.6, median 34.5) and ISS patients (mean 29.2mm3±24.1, median 19.9) was not significant (p=0.2685). The mean percent of the gland occupied by the cyst for GHD patients was 15.3%±12.8 (median 13.5) and for ISS was 7.1%±8.0 (median 4.8). The difference between these two groups was statistically significant (p=0.0032). For males, the difference between percent gland occupied by cyst in the GHD (mean 16.4%±14.3, median 13.5) and ISS (mean 6.7%±9.0, median 4.1) groups was significant (p=0.0085). For females, the difference between percent gland occupied by cyst in the GHD (mean 11.8%±5.6, median 10.9) and ISS (mean 7.8%±6.6, median 5.4) groups was not significant (p=0.1629). When looking at cyst size for the different populations, it was found that from 0-15% of gland occupied 55.6% of the GHD patients, 85% of ISS patients, and 66.1% of all the patients had cyst volumes in this range. For the greater than 15% of the pituitary gland occupied, 44.4% of GHD patients, 15% of ISS patients, and 33.9% of all the patients were found in this category. Statistical analysis showed that there was a significant difference between the percentage of GHD patients and ISS patients in the greater than 15% volume range (p=0.0387).  Discussion: The incidence of pituitary cysts in short children does not seem significantly different from the general population. However, our data suggests that patients with larger cysts would more likely be GHD. It is possible they may develop further pituitary dysfunction. Follow up of these patients will be necessary to determine any long term consequences.

(1)Sanno N, Oyama K, Tahara S, Teramoto A, Kato Y. A survey of pituitary incidentaloma in Japan. Eur J Endocrinol. Aug 2003;149(2):123-127. (2)Takanashi J, Tada H, Barkovich AJ, Saeki N, Kohno Y. Pituitary cysts in childhood evaluated by MR imaging. AJNR Am J Neuroradiol. Sep 2005;26(8):2144-2147. (3)Baskin DS, Wilson CB. Transsphenoidal treatment of non-neoplastic intrasellar cysts. A report of 38 cases. J Neurosurg. Jan 1984;60(1):8-13. (4)Shanklin WM. On the presence of cysts in the human pituitary. Anat Rec. Aug 1949;104(4):379-407. (5)McGrath P. Cysts of sellar and pharyngeal hypophyses. Pathology. Apr 1971;3(2):123-131.

Nothing to Disclose: RAN, SS, SF, KR, BP, MT, QS, MF

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