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Purpose: Immature PIT-1 lineage tumors are classified as high-risk pituitary adenomas/pituitary neuroendocrine tumors (PitNETs) under the 2022 WHO Classification, yet clinical outcome data remain scarce. This study aimed to characterize clinicopathological features and treatment outcomes of this rare entity. Methods: We retrospectively analyzed 13 patients with pathologically confirmed immature PIT-1 lineage tumors who underwent surgery at our tertiary center between January 2022 and December 2024. Diagnoses were established according to WHO 2022 criteria using comprehensive transcription factor (TF) immunohistochemistry. Clinical, radiological, histopathological, treatment, and follow-up data were evaluated. Results: Immature PIT-1 lineage tumors accounted for 4% (21/525) of surgically treated pituitary adenomas, of whom 13 with complete follow-up data constituted the primary analysis cohort. Median age was 37 years (range: 25–73), with female predominance (61.5%). Notably, 61.5% presented with hormonal hypersecretion: acromegaly (38.5%), TSH-secreting tumors (15.4%), and GH-PRL co-secretion (7.7%). All patients had macroadenomas (median diameter 28 mm (range: 15–59 mm)); 38.5% demonstrated cavernous sinus invasion (Knosp grades 3–4). Immunohistochemically defined plurihormonal phenotype was present in 77% of cases; cytologic atypia was identified in all cases. Despite maximal surgical resection, residual disease persisted in 46% and 31% required reoperation at 16-month follow-up (range: 4–51 months). The median Ki-67 proliferation index was 4% (IQR: 2–10%; range: 1–35%), and the median mitotic count was 4 per 2 mm² (IQR: 1–8; range: 1–20). Conclusion: Immature PIT-1 lineage tumors exhibit aggressive behavior with high residual disease rates, with 31% of patients requiring reoperation, 23% receiving adjuvant radiotherapy, and somatostatin analogue resistance observed in two patients. Routine TF immunohistochemistry is essential for accurate diagnosis; management requires maximal safe surgical resection and intensive long-term surveillance.

Background: Calcitonin gene-related peptide (CGRP) is a potent vasodilatory neuropeptide involved in inflammation, vascular regulation, and pain mechanisms with potential relevance to endocrine and neurological processes. Furthermore, it exerts specific effects on the tumor microenvironment in certain malignancies. The contribution of CGRP to pituitary adenogenesis has yet to be elucidated. This study aimed to investigate CGRP expression by immunohistochemistry in patients with acromegaly and nonfunctioning pituitary adenomas (NFPAs) and its associations with tumor features, symptoms, and treatment response. Methods: This study included tissue samples obtained from 49 patients who were followed and underwent transsphenoidal surgery at our center: 30 with acromegaly and 19 with NFPAs. Tumor samples were evaluated for CGRP using a polyclonal anti-CGRP antibody (GeneTex, 1:200). Clinical, radiological, and surgical data were collected. Histopathology included hormone staining, estrogen receptor, granularity, transcription factors, Ki-67, and mitotic count. Results: CGRP positivity was observed in 50% of acromegaly patients and in none of the NFPA group (p < 0.001). CGRP expression was not significantly associated with tumor size, invasion, need for surgery, residual tumor, treatment resistance, or granularity. In acromegaly cases with CGRP-positive adenomas, chronic headache tended to be more common (40% vs. 13%, p = 0.09), and postoperative headache resolution rate was lower (33.3% vs. 80%, p = 0.07). The postoperative remission rate tended to be lower (60% vs. 86.7%, p = 0.09). Conclusion: CGRP was found to be notably present in somatotropin-producing adenoma tissues, yet it was entirely absent from nonfunctioning adenoma tissues. The detection of CGRP within adenoma tissue could correlate with an increased incidence of persistent headaches and diminished postoperative remission probabilities in acromegaly.

Amyloid spherule-containing prolactinomas are rare entities associated with dopamine agonist (DA) resistance and aggressive behaviour. We report a giant amyloid spherule-containing prolactinoma with a substantial tumour burden and markedly elevated prolactin levels, highlighting novel multimodal therapeutic strategies. A 49-year-old man presented with headache and visual disturbance. Imaging revealed a giant pituitary macroadenoma (63 × 84 × 46 mm) with Knosp grade 4 cavernous sinus invasion and clivus erosion. Laboratory investigations revealed marked hyperprolactinemia (prolactin (PRL): 30,969 ng/mL) and autonomous growth hormone (GH) hypersecretion. Histopathology confirmed a sparsely granulated lactotroph tumour with extensive amyloid spherules and dystrophic calcifications (Ki-67: 8%). Notably, immunohistochemistry demonstrated PRL positivity without GH immunoreactivity, suggesting tumour heterogeneity with sampling limitations. Comprehensive systemic amyloidosis screening, the first systematic evaluation reported for this entity, excluded systemic disease. Following surgical debulking with extensive residual disease, postoperative cabergoline treatment resulted in a reduction in the PRL (4,700→927 ng/mL). Given the presence of amyloid-associated dopamine resistance, cabergoline was discontinued, and radiotherapy (RT) (45 Gy) was initiated to control the amyloid burden, followed by temozolomide. Based on evidence from other malignancies suggesting RT-mediated amyloid reduction, cabergoline was reintroduced postradiotherapy without paradoxical tumour growth. Concurrent cabergoline-temozolomide therapy, a novel approach that differs from conventional sequential protocols, achieved a dramatic response: 93.4% prolactin reduction (10,320→677 ng/mL) and 52.4% tumour volume reduction. This superior outcome far exceeded that of initial postsurgical cabergoline monotherapy (80% reduction), suggesting that RT successfully modulated the amyloid burden and restored dopamine sensitivity. This case suggests that RT may restore dopamine agonist sensitivity in patients with amyloid-containing prolactinomas, potentially enabling concurrent dopamine agonist-temozolomide therapy in refractory cases, warranting further validation.

Cerebral vasospasm (CV) following spontaneous subarachnoid hemorrhage is a serious complication that can lead to delayed cerebral ischemia, significantly increasing both morbidity and mortality. This article offers an in-depth examination of the pathophysiological mechanisms, risk factors, diagnostic strategies, and currently available treatment options concerning CV. Several distinct yet interconnected processes contribute to the development of vasospasm, such as oxidative stress driven by oxyhemoglobin, increased endothelin-1 activity, diminished nitric oxide availability, endothelial dysfunction, vascular inflammation, and sympathetic overactivation. In symptomatic cases, digital subtraction angiography remains the most reliable modality for diagnosis, offering detailed vascular visualization and the opportunity for concurrent therapeutic intervention. Among pharmacological agents, oral nimodipine is the only drug with proven efficacy in enhancing functional outcomes and is strongly endorsed by current clinical guidelines (Class I, Level A). In cases of refractory vasospasm, endovascular treatments such as transluminal balloon angioplasty and intra-arterial vasodilator infusion play a critical role. The management of CV requires an individualized, time-sensitive, and multimodal approach in both diagnosis and therapy. There remains a need for advanced randomized controlled trials and standardized treatment protocols in this field.

Purpose To evaluate the clinical characteristics, surgical outcomes, and endocrinological follow-up findings of pediatric patients who underwent surgical treatment for sellar and parasellar masses. Methods Forty-seven patients who underwent surgical treatment for sellar and parasellar masses between January 2021 and January 2025 were retrospectively analyzed. All patients were followed up in the pediatric endocrinology clinic. Demographic characteristics, clinical findings, surgical approaches, histopathological diagnoses, and postoperative outcomes were evaluated. Endocrinological assessments were performed using standardized hormone assays with age- and sex-specific reference ranges. Results Twenty-eight (59.6%) patients were female, with a median age of 10.1 years (range: 2.5–17.5). The most common presenting complaint was headache (46.8%), followed by visual impairment (27.7%) and short stature (14.9%). Histopathological examination revealed non-pituitary masses in 35 (74.5%) patients, with craniopharyngioma being the most frequent (44.7%). An endoscopic approach was used in 42 (89.4%) patients, and total resection was achieved in 30 (63.8%) patients. Panhypopituitarism developed in 27 (57.4%) patients postoperatively, representing a significant increase from preoperative rates (10.6%, p < 0.001). During a median follow-up of 2.5 years, recurrence occurred in 10 (21.3%) patients and mortality in 11 (23.4%) patients. Patients with non-pituitary tumors had significantly higher rates of re-operation (37.1% vs. 0%, p = 0.012) and mortality (31.4% vs. 0%, p = 0.024) compared to those with pituitary tumors. Conclusions Surgical management of pediatric sellar and parasellar masses carries significant risk of endocrinological complications, particularly panhypopituitarism. A multidisciplinary approach combining appropriate surgical technique selection, comprehensive endocrinological evaluation, and long-term follow-up is essential for optimal patient outcomes. Non-pituitary masses, especially craniopharyngioma, are associated with higher morbidity and mortality rates.

Purpose Bilateral inferior petrosal sinus sampling (BIPSS) is the gold standard for localizing ACTH-dependent Cushing’s syndrome (CS). While corticotropin-releasing hormone (CRH) was initially used for stimulation, desmopressin has become a common alternative. This research evaluates desmopressin’s effectiveness in lateralizing Cushing’s disease (CD) during BIPSS compared to CRH stimulation. Methods The study included 33 individuals with ACTH-dependent CS who underwent BIPSS and had diagnoses confirmed by endoscopic endonasal transsphenoidal pituitary surgery (EETPS). Fourteen participants underwent BIPSS with CRH and 19 with desmopressin. A comparative analysis was conducted. Results BIPSS accurately lateralized 76% of cases, specifically, 71% with CRH and 79% with desmopressin (p = 0.2). For tumors < 6 mm on MRI, overall accuracy was 82%, namely, 75% with CRH and 90% with desmopressin (p = 0.4). IPSS achieved 100% accuracy in the four cases with no lesion on preoperative MRI. Conclusion This study demonstrates no significant difference in lateralization accuracy between desmopressin and CRH for IPSS. In challenging cases, especially those with microadenomas or non-lesional CD, desmopressin with IPSS aids in preoperative lateralization.