Objective: The number of studies on the incidence of pituitary adenomas (PAs) is limited. The aim of this study was to evaluate the standardised incidence rate (SIR) of PAs in western Sweden. Design, subjects and methods: Data from adult patients diagnosed with PAs in 2001-2011, living in the Vä stra Gö taland County, were collected from the Swedish Pituitary Registry (SPR). In addition, medical records on all patients diagnosed with PAs at the six hospitals in the region were reviewed. In total, 592 patients were included in the study. Age-SIR, given as rate/100 000 inhabitants (95% CI), was calculated using the WHO 2000 standard population as a reference. Results: The total SIR for PAs was 3.9/100 000 (3.6-4.3); 3.3/100 000 (2.9-3.7) for men and 4.7/100 000 (4.1-5.3) for women. In men, SIR increased with age, while in women SIR peaked at 25-34 years, mainly due to prolactinomas. Non-functioning PA (NFPA) was the most common PA (54%, 1.8/100 000 (1.6-2.0)) followed by prolactinomas (32%, 1.6/100 000 (1.3-1.9)), acromegaly (9%, 0.35/100 000 (0.25-0.45)), Cushing's disease (4%, 0.18/100 000 (0.11-0.25)) and TSH-producing PA (0.7%, 0.03/100 000 (0.00-0.05)). The proportion of macroadenomas for NFPA was 82%, prolactinomas 37%, GH-producing PA 77%, ACTH-producing PA 28% and TSH-producing PA 100%. The lifetime risk for PAs was 0.27% (0.24-0.31) in men and 0.29% (0.26-0.33) in women. Conclusion: This study provides a reliable estimate on the overall incidence of PAs and confirms an increased incidence of PAs compared with studies conducted in the pre-magnetic resonance imaging era. The lower proportion of prolactinomas compared with previous studies is probably explained by the different criteria used.

Thyrotropin (TSH)-secreting adenomas (TSHomas) are the rarest form of pituitary adenomas, and most endocrinologists will see few cases in a lifetime, if any. In most cases, the diagnostic approach is complicated and cases may be referred after being presented as a syndrome of inappropriate TSH secretion or as a pituitary mass. This review aims to cover the past, present and possible future diagnostic approaches to TSHomas, including different clinical presentations, laboratory assessment and imaging advances. The differential diagnoses will be discussed, as well as possible coexisting disorders. By evaluating the existing reports and reviews describing this rare condition, this review aims to present a clinically practical suggestion on the diagnosic workup for TSHomas, Major advances and scientific breakthroughs in the imaging area in recent years, facilitating diagnosis of TSHomas, support the belief that future progress within the imaging field will play an important role in providing methods for a more efficient diagnosis of this rare condition.

Objectives 68 Ga‐DOTATOC PET targets somatostatin receptors (SSTRs) and is well established for the detection of SSTR‐expressing tumors, such as gastrointestinal neuroendocrine tumors. Pituitary adenomas, recently designated as pituitary neuroendocrine tumors (PitNETs), also express SSTRs, but there has been no previous evaluations of 68 Ga‐DOTATOC PET in PitNET patients. The aim of this pilot study was to evaluate the diagnostic properties of 68 Ga‐DOTATOC PET in the most common PitNET, ie non‐functioning (NF)‐PitNET. Design/Patients NF‐PitNET patients (n = 9) and controls (n = 13) were examined preoperatively with 68 Ga‐DOTATOC PET for 45 min after tracer injection in dynamic list mode. Tumor specimens were collected during surgery in patients. MRI and PET images were co‐registered using PMOD software. The maximum standard uptake value (SUVmax) was analyzed in manually outlined regions of interest (ROI) around the tumor in patients and around the pituitary gland in controls. Immunohistochemical analyses were conducted on tumor specimens for assessment of tumor cell type and SSTR expression. Results Median SUVmax (IQR) was lower in patients than in controls (3.9 [3.4‐8.5] vs 14.1 [12.5‐15.9]; P < .01]. In ROC analysis, the area under the curve was 0.87 (P < .01) for SUVmax, with 78% sensitivity and 92% specificity. Immunohistochemical analysis showed NF‐PitNETs were of gonadotroph (n = 7) and corticotroph (n = 2) origin. SSTR expression was high for SSTR3, low‐to‐moderate for SSTR2, and low for SSTR1 and SSTR5. Conclusions This proof‐of‐concept study shows that 68Ga‐DOTATOC PET can be used to differentiate between normal pituitary tissue and NF‐PitNET.