Trejo-Lopez, Jorge A

ABSTRACT Objective Pituitary carcinoma (PC) is defined by the presence of metastasis from a pituitary tumour. PC is rare, therefore information regarding survival and factors influencing survival are limited. We sought to assess overall survival following the diagnosis of PC and to determine factors associated with outcome. Design Retrospective case series. Patients Patients with PC who attended the Mayo clinic between 1997 and 2025. Measurements Information regarding patient demographics, tumour characteristics, management and outcomes were extracted. Results In total 25 patients (11 women, 44%) were diagnosed with PC (median age 56 years, range, 44–78). The most common cell type was a corticotroph tumour ( n = 15, 60%). All but one patient had pituitary directed surgery and all received pituitary adenoma (PA) directed radiation therapy. Metastases were identified a median 6 years (range, 1–32) after initial PA diagnosis. At last follow‐up, 10 (40%) patients were alive, 12 (48%) died of PC, and 3 (12%) died from other causes. The median survival time of patients from PC diagnosis was 3 years. The 1‐, 5‐ and 10‐year survival rates were 59%, 37% and 15%, respectively. Increased survival probability was associated with temozolomide treatment ( n = 9) at some point in treatment plan ( p = 0.026), the use of systemic therapy vs locoregional treatment ( p = 0.045), female sex ( p = 0.011), and in nonfunctional tumours ( p = 0.023). Conclusion PC carries a poor prognosis, with a median survival of only 3 years. Improved survival was associated with temozolomide exposure, female sex, and nonfunctional tumour subtype and underscores the prognostic relevance of tumour biology and treatment approach.

Abstract Diffuse hemispheric glioma, H3 G34‐mutant (DHG‐H3 G34) has been primarily molecularly characterized by methylation profiling and sequencing studies. We describe an integrated histomolecular evaluation including high‐resolution copy number profiling of a series of 60 DHG‐H3 G34 to further our understanding of the spectrum of genetic changes associated with this tumor type. Cases were clinically tested using an 187‐gene mutation and fusion targeted neuro‐oncology next‐generation sequencing panel ( n = 60) and Oncoscan chromosomal microarray ( n = 26) by a single laboratory (2018–2022). A subset of cases had immunohistochemical results for OLIG2 ( n = 42), p53 ( n = 48), and ATRX ( n = 46), and methylation array data ( n = 8). Median age at testing was 21 years (range, 12–50). No significant difference was noted in clinical, histopathological, and mutational profile between pediatric and adult patients. H3‐3A G34 mutations included G34R ( n = 56; 94%), G34V ( n = 3), and a non‐canonical G34E ( n = 1). Concurrent mutations most often involved TP53 ( n = 55; 92%), ATRX ( n = 50; 83%), and PDGFRA ( n = 34; 57%). A reportedly primary tumor was confirmed to be hypermutant and had a PMS2 mutation. A single case also showed an FGFR3::FAM184B fusion. All cases with available chromosomal microarray data had unbalanced genomes, which were often complex (14/26; 54%). The most frequent recurrent copy number abnormalities were losses involving 3q, 4q, 10q, 13q, and 18q, and 17p copy‐neutral loss of heterozygosity (cnLOH) encompassing TP53 . This copy number profile was reminiscent of that seen in Grade 4 IDH‐mutant astrocytomas. Collectively, a TP53 abnormality at copy number (12/26, all cnLOH), sequence (55/60) and protein expression (46/48) level was detected in all 60 cases. In conclusion, integrated high‐resolution copy number and histomolecular analysis expanded the spectrum of genetic changes associated with DHG‐H3 G34, including the presence of universal TP53 abnormalities with frequent cnLOH—a copy number abnormality that has been largely unrecognized—for this new 2021 World Health Organization central nervous system tumor type.