Aggressive pituitary tumors (PitNETs)

Alpha thalassemia/mental retardation X-linked (ATRX) protein expression in human pituitary neuroendocrine tumours and its reported correlation to prognosis and clinical outcomes: A systematic review

Mutations in Alpha thalassemia/mental retardation X-linked (ATRX) have been implicated in several cancers, including gliomas, sarcomas, neuroendocrine tumors, and other mesenchymal malignancies. ATRX loss contributes to oncogenesis, accelerates tumor growth, and reduces survival by disrupting epigenetic and telomere mechanisms. Additionally, ATRX loss can increase tumor sensitivity to treatment therapies. While research has explored ATRX expression in many cancers, data on its relationship to prognosis in pituitary neuroendocrine tumors (PitNETs) remain inconsistent. This systematic review aims to summarize all available studies on ATRX mutations and expression in PitNETs. A systematic search of PubMed, Scopus, and EMBASE databases was conducted to identify publications between 2014 and 2025 that investigated ATRX mutations or expression in PitNETs, following PRISMA 2020 guidelines. Of 32 identified studies, ten met the inclusion criteria, covering a total of 513 PitNETs. Only 20 tumors (3.9%) showed a loss of ATRX expression. Among these, 60% exhibited corticotrophic pathology, while 20% displayed lactotrophic pathology. A small subset of tumors (30%) was classified as pituitary carcinomas with aggressive and proliferative characteristics. Additionally, 10% demonstrated the alternative lengthening of telomeres (ALT) phenotype, 50% had concurrent TP53 mutations, and 25% had elevated Ki-67 indices, indicating a higher proliferative index. Although ATRX mutations are rare in PitNETs, tumors with ATRX loss tend to be more aggressive and exhibit proliferative and transformative properties. Due to the limited number of cases, further studies with larger, prospective cohorts are needed to better understand the role of ATRX loss in PitNET progression and aggressiveness.

Flow cytometry immune profiling of recurrent and newly diagnosed growth hormone secreting pituitary neuroendocrine tumors: comparison of two clinical cases

Early detection of aggressive pituitary neuroendocrine tumors (PitNETs) remains challenging due to the absence of reliable markers that can predict disease progression. Aggressive tumors are typically identified through long-term observation. Tumor immune microenvironment (TIME) is crucial for understanding PitNETs' heterogeneity and identifying potential predictors of tumor aggressiveness. In this study, we analyzed immune profile of micro- and macroenvironment in two somatotropinomas (aggressive and non-aggressive) using flow cytometry. We observed lymphopenia and elevated neutrophil levels in the periphery in the patient with tumor recurrence. The aggressive TIME showed greater leukocyte infiltration, with lymphoid cells predominating over myeloid cells along with a higher proportion of CD4 + T cells over CD8 + T cells. We detected double-positive CD4 + CD8 + population, high level of regulatory T cells and a sharp increase in PD-1 + expressing T cells over six months during recurrence. In the blood of the patient with tumor recurrence, we observed reduced granule-mediated cytotoxicity of CD8 + T cells and NK-cells. In the aggressive TIME the number of effector cells producing perforin and granzyme B-both independently and simultaneously was significantly lower. The proportion of CD3-CD20- NK cells and CD3-CD56 + NK cells was low after the first recurrence but increased sharply after six months. The ratio of monocyte subpopulations in tumor differed from that in blood, with CD16 + expressing monocytes predominating in the TIME of both patients. M2 macrophages in TIME rose sharply to 60.8% over six months during recurrence. In several immunological parameters, the patient with tumor recurrence exhibited a more pronounced immunosuppressive profile.

The expression of VDACs and Bcl2 family genes in pituitary adenomas: clinical correlations and postsurgical outcomes

Introduction

Pituitary adenomas (PAs) are benign tumors with high prevalence and, occasionally, aggressive course. The tumorigenesis of these lesions is not completely understood at the molecular level. BAK1 and BAX proteins play fundamental roles in apoptosis and seem to interact with VDAC proteins, whose expressions have been markedly altered in cancer, impacting their prognosis.

Objective

to evaluate the gene expression of VDAC1, VDAC2, BAK1 and BAX and their association with clinical and imaging characteristics in PA.

Methods

Clinical-epidemiological data were collected from 117 tumor samples from patients affected by PA. Invasiveness was assessed by the Knosp scale. Gene expression was examined by real-time PCR. Relative expression analysis was performed by 2^(-DDCt) method.

Results

The sample was mainly composed of women (69/117 - 57.2%). Tumor subtypes observed were Non-Functioning (NF) (73/117 - 62.4%), Acromegaly (24/117 - 20.5%) and Cushing's Disease (CD) (20/117 - 17.1%). Compared to normal tissue, there was a significant reduction in VDAC1 expression in the Acromegaly (p=0.029) and NF (p=0.002) groups. BAX expression was lower in all groups (p <0.001; p=0.007; P =0.005). No difference was found in VDAC2 and BAK1 expression, compared to normal pituitary. Overexpression of VDAC2 occurred in PAs with post-surgical regrowth (p=0.042). A strongly negative correlation was observed in BAX and BAK1 expression in CD.

Conclusion

The results indicated that downregulations of VDAC1 and BAX may be related to resistance to apoptosis. In contrast, overexpression of VDAC2 in regrowing PAs suggests an antiapoptotic role for this gene. In summary, the genes evaluated might be involved in the biopathology of PAs.

Clinicopathological analysis of non-functioning pituitary adenomas (PAs) according to the 2022 WHO classification

PURPOSE

For asymptomatic non-functioning pituitary adenomas (NFPAs), conservative approaches such as observation are preferred. However, some NFPAs exhibit poor prognoses. Thus, the purpose of this study was to investigate clinicopathological characteristics of tumors for identifying those with unfavorable prognoses.

METHODS

A total of 125 patients with NFPAs who underwent surgery between November 2017 and December 2022 at our institution were retrospectively analyzed. Clinical, radiological, and pathological data, including hormone profiles, tumor size, presence of cavernous sinus invasion, and Ki-67 index levels, were reviewed. High-risk PAs were identified according to 2022 WHO criteria. Statistical analyses including Kaplan-Meier survival analysis and Cox regression were performed to evaluate factors associated with tumor progression or recurrence.

RESULTS

A high-risk group demonstrated a significantly higher rate of tumor progression/recurrence than a low-risk group (p-value = 0.004). In multivariate analysis, the high-risk group at the time of diagnosis remained as an independent prognostic factor for NFPAs (p-value = 0.0148). The high-risk group also had a higher percentage of younger patients (80.0% in the high-risk group vs. 62.2% in the low-risk group, p-value = 0.016) and female patients (91.4% vs. 34.4%, p< 0.001). The presence of cavernous sinus invasion and higher Ki-67 index levels were more commonly observed in the high-risk group, although these factors did not significantly impact the overall prognosis.

CONCLUSION

Our findings indicate that patients with high-risk NFPAs have a more aggressive disease course and a higher rate of progression or recurrence. This high-risk group has higher prevalence of younger and female patients. They may benefit from closer monitoring and possibly more aggressive treatment approaches.

Differences in invasiveness and recurrence rate among nonfunctioning pituitary neuroendocrine tumors depending on tumor subtype

PURPOSE

To clarify the invasiveness to surrounding structures and recurrence rate of each subtype of nonfunctioning pituitary neuroendocrine tumor (Pit-NETs) according to the WHO 2022 classification.

METHODS

This retrospective study utilized data from 292 patients with nonfunctioning Pit-NETs treated with initial transsphenoidal surgery. Recurrence was evaluated on 113 patients who were available for a magnetic resonance imaging follow-up ≥ 60 months. All tumors were assessed by immunohistochemical staining for Pit-1, T-PIT, and GATA3. Invasiveness to surrounding structures was evaluated based on intraoperative findings.

RESULTS

Cavernous sinus invasion was found in 47.5% of null cell tumors, 50.0% of Pit-1 lineage tumors, 31.8% of corticotroph tumors, and 18.3% of gonadotroph tumors. Dura mater defects in the floor of sellar turcica, indicating dural invasion, were found in 44.3% of null cell tumors, 36.4% of corticotroph tumors, 16.7% of Pit-1 lineage tumors, and 17.3% of gonadotroph tumors. In logistic regression analysis, Pit-1 (OR 5.90, 95% CI 1.71-20.4, P = 0.0050) and null tumors (OR 4.14, 95% CI 1.86-9.23, P = 0.0005) were associated with cavernous sinus invasion. Recurrence was found in 8 (4.9%) patients, but without significant differences between tumor subtypes. The presence of cavernous sinus invasion was correlated with recurrence (HR = 1.95, 95% CI 1.10-3.46, P = 0.0227).

CONCLUSION

Among nonfunctioning Pit-NETs, Pit-1 lineage tumors tend to invade the cavernous sinus, corticotroph tumors may produce dura mater defects, and null cell tumors tend to cause both. Pit-NETs with cavernous sinus invasion require a careful attention to recurrence.