Lania, Andrea G

Abstract Objective Increased frequency of neuroimaging has led to enhanced identification of small nonfunctioning pituitary adenomas (NFPAs) leading, in many cases, to extensive follow-up. However, the value of ongoing monitoring of these incidental lesions remains unclear. The study aims to determine the need for surgical intervention and assess the risks of developing new endocrinopathies during follow-up in patients with conservatively treated micro-NFPAs. Design A systematic review and individual participant data (IPD) meta-analysis. Methods We conducted a bibliographical search of PubMed and EMBASE to identify relevant studies. Authors of eligible studies were invited to share IPD. Cohort studies including patients with conservatively treated micro-NFPAs with at least 1 follow-up magnetic resonance imaging were considered eligible. Fourteen studies met inclusion criteria. Six authors provided IPD (N = 647). Data were reanalyzed for verification. In cases of discrepancies the original authors were contacted for authentication. Results Risk estimates were reported as number of events per 100 person-years (PYs). Estimates were pooled using the 2-step approach. Overall probability of surgery was 0.2/100 PYs (95% CI: 0.0-0.4; I2 = 28%). Probability of surgery due to visual impairment was 0.1/100 PYs (95% CI: 0.0-0.2; I2 = 0%). Both were independent of baseline tumor size (≥6 or <6 mm), sex, or age (P values >.40). Risk of developing a new endocrinopathy was 1.0/100 PYs (95% CI: 0.4-1.6; I2 = 0%). Data for classical meta-analysis were available for 7 studies (N = 1089) and supported the IPD results. Conclusions These data suggest that routine follow-up of micro-NFPAs can be reduced significantly and that available guidelines should be revisited.

AimTo describe four novel primary epithelial tumours of the sella with papillary architecture and Thyroid Transcription Factor 1 (TTF‐1) expression.MethodsParaffin‐embedded tissue from the four cases and recurrence of patient 1 was investigated with haematoxylin–eosin, special histochemical stains, immunohistochemistry with a broad panel of antibodies and next‐generation sequencing. The ultrastructure of one tumour was studied in tissue retrieved from paraffin.ResultsThe lesions occurred in three females aged 20, 26 and 42 years and a male aged 49 years. They presented with signs and symptoms secondary to pituitary stalk compression. Preoperative neuroimaging documented mixed solid and cystic, enhancing sellar masses with suprasellar extension. Histologically, the tumours showed thin papillae lined by a single layer of cytokeratin and TTF‐1‐positive cuboidal and cylindrical cells with mildly atypical nucleus. Next‐generation sequencing performed in three cases did not identify any mutations. The main differential diagnosis included metastasis from lung or thyroid carcinoma, extraventricular choroid plexus papilloma and sellar ependymoma.ConclusionWe suggest the descriptive term of primary papillary epithelial tumour of the sella (PPETS) for this entity and propose that it could represent the intracranial equivalent of thyroid‐like low‐grade nasopharyngeal papillary adenocarcinoma. The cell of origin of PPETS remains undetermined although the intense and ubiquitous expression of TTF‐1 may suggest a derivation from the infundibulum or ventricular recess. Our study expands the spectrum of sellar TTF‐1‐positive tumour and challenges the view that they all derive from pituicytes.