Cell Lineage-Specific Differences in Clinical Behavior of Non-Functioning Pituitary Adenomas.

Context: Immunohistochemistry (IHC) of cell lineage-specific transcription factors (TFs) has been added to the histopathological classification of pituitary adenomas since 2017, resulting in new histopathological subtypes of TF+/hormone-non-functioning pituitary adenomas (NFPAs) and a reduction in the prevalence of null cell adenomas (NCAs).

Objective: This work aimed to evaluate associations between expression of cell lineage-specific TFs by IHC and radiological invasion and prognosis of NFPAs.

Data sources: A literature search in Medline, Embase, and CENTRAL was performed from inception up to July 11, 2023.

Study selection: Eligible studies were cohort studies reporting on radiological invasion, recurrence, and/or radiotherapy in patients with NFPAs who tested positive for one cell lineage-specific TF or negative for all 3. Finally, 27 out of 1985 studies were included.

Data extraction: Two authors independently extracted data and critically appraised risk of bias using the Quality In Prognostic Studies (QUIPS) tool.

Data synthesis: Random-effects inverse variance models were used to pool effect sizes. Prevalence rate ratios (PRRs) were calculated using the Mantel-Haenszel method. Cavernous sinus invasion was more prevalent in NCAs and TPIT+ NFPAs compared with SF1+ NFPAs (PRR 1.60; 95% CI, 1.22-2.08, I2 10%, 95% prediction interval [PrI] 1.23-2.06; P = .0036, and PRR 1.43; 95% CI, 1.21-1.70, I2 0%, 95% PrI 1.17-1.76; P = .0017, respectively), and in NCAs compared with PIT1+ (PRR 1.44; 95% CI, 1.01-2.06, I2 0%, 95% PrI 0.83-2.50; P = .0454). A limited number of studies precluded data syntheses of recurrence and radiotherapy.

Conclusion: The use of cell lineage-specific TFs by IHC enables to detect histopathological subtypes of NFPAs with distinct clinical behavior.