Characteristics of Thyroid lesion in patients with Acromegaly

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: SUN 88-129-Acromegaly & Prolactinoma
Clinical
Sunday, June 16, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board SUN-113
Jung Soo Lim*1, Sun Ho Kim2 and Eun Jig Lee2
1Yonsei University Wonju College, Gangwon-do, South Korea, 2Yonsei University College of Medicine, Seoul, South Korea
Background Several studies reported that acromegaly is associated with an increased risk of thyroid cancer or goiter. Elevated IGF-1 levels have been thought to contribute to the abnormal tumor growth. However, there is still debate on the prevalence of thyroid cancer or the actual effect of IGF-1 on thyroid in patients with acromegaly.

Objective To investigate characteristics of thyroid lesion in patients with acromegaly, thyroid ultrasonographic findings and associated hormone levels were evaluated.

Methods We retrospectively reviewed medical records of 464 patients (mean age 42.57 ± 11.41 yrs, male 204, female 260) who were diagnosed with acromegaly and underwent transsphenoidal surgery (TSS) in Severance hospital between 1995 and 2012. In addition, IGF-1 and thyroid hormone levels were analyzed in 31 acromegalic patients who had thyroid ultrasonography (US) as an initial test between 2005 and 2012.

Results A total of 10 subjects (2.2%) were diagnosed with papillary thyroid cancer: four subjects had previous history of thyroid cancer before the diagnosis of acromegaly, and one also had cervix cancer. Among those who underwent baseline thyroid US before TSS, six subjects (19.4%) were diagnosed with thyroid cancer and only three (9.7%) showed normal findings. Among 5 subjects who had unilateral thyroidectomy due to large thyroid nodules or follicular adenoma, thyroid nodules on the opposite side were found in all three subjects who underwent thyroid US. Free T4 levels, but not IGF-1 or TSH levels, showed significant difference between thyroid cancer group and thyroid nodule group (P= 0.013).

Conclusion Although the overall prevalence of thyroid cancer in acromegalic patients was low, thyroid nodules were observed in most patients. Therefore, further research on the clinical significance of thyroid nodule found in acromegaly will be needed.

Nothing to Disclose: JSL, SHK, EJL

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