title: Nabothian cyst a predominant cause of false-positive iodine uptake in uterus: comparison of SPECT/CT and pelvic MRI.
abstract: OBJECTIVE
  Many cases of unexpected radioiodine uptake have been reported, including physiological uptake in healthy tissue and in both benign and malignant nonthyroidal lesions. However, iodine uptake in the uterus has not been well assessed. In this article, we systemically analyzed iodine uptake in the uterus and identified the site in which uptake occurred.
  
  
  METHODS
  Seventy-six female patients who underwent SPECT/CT from neck to pelvis were included in this study; 5 patients with uterine uptake received pelvic MRI. Iodine uptake in the uterus was diagnosed with SPECT/CT and compared with the findings of the MRI. Serum TSH level, administered dose of iodine-131 and number of radioiodine therapies were compared between the 2 groups with and without iodine uptake in the uterus.
  
  
  RESULTS
  Twenty (26.3%) of 76 patients showed iodine uptake in the uterine cervix on SPECT/CT. It was difficult to distinguish the uptake in the uterus from that in the urinary bladder or rectum using only planar images. The patients with the uterine uptake were younger than those without (median age, 46.5 vs. 62, P = 0.011). There were no significant differences in serum TSH level, administered dose of iodine-131, or number of radioiodine therapies between the 2 groups. In all instances of the 5 patients who underwent pelvic MRI, iodine uptake in the uteri was located in nabothian cysts.
  
  
  CONCLUSIONS
  Iodine uptake in the uterus is frequently found if pelvic SPECT/CT is performed. Nabothian cysts are a predominant cause of iodine uptake in the uterine cervix.
authors: From the *Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, †Department of Health Sciences, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors: Takuro
authors: T
authors: Isoda
authors: Shingo
authors: S
authors: BaBa
authors: Yasuhiro
authors: Y
authors: Maruoka
authors: Yoshiyuki
authors: Y
authors: Kitamura
authors: Akihiro
authors: A
authors: Nishie
authors: Masayuki
authors: M
authors: Sasaki
authors: Hiroshi
authors: H
authors: Honda
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003560:Cysts / Q000000981:diagnostic imaging*; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D064847:Multimodal Imaging; D015899:Tomography, Emission-Computed, Single-Photon; D014057:Tomography, X-Ray Computed; D002583:Uterine Cervical Neoplasms / Q000000981:diagnostic imaging*