Background: The 5th edition of WHO classification (WHO5) renamed pituitary adenoma as pituitary neuroendocrine tumor (PitNET), aligning with NET nomenclature from other sites.This study investigated the clinicopathological characteristics of surgically resected PitNET based on the WHO5 classification. Methods: A retrospective analysis was conducted on 210 cases of surgically resected and pathologically confirmed PitNET treated at Seoul National University Hospital from 2021 to 2023. The tumors were graded using the French five-tiered grading system proposed by Trouillas et al. Detailed information on grade 3 metastatic PitNET cases is provided. Results: The cohort’s median age was 53 years (age range: 8–84 years), with a male-to-female ratio of 1:1.1. Mean tumor size was 2.5 cm (range: 0.1–6.5 cm). Macroadenomas predominated (91.9%), followed by microadenoma (6.7%), and giant tumors (1.4%), with 56.2% extending suprasellarly. SF1-lineage PitNET was most prevalent (49.5%), followed by PIT1-lineage (23.3%) and TPIT-lineage (17.1%). Null cell tumors (5.7%) and unclassified plurihormonal PitNET (4.3%) were rare. PIT1-lineage PitNET comprised somatotrophs (47.0%), mature plurihormonal PIT1 lineage tumors (18.4%), thyrotrophs (16.3%), immature PIT1-lineage tumors (16.3%), and acidophilic stem cell tumors (n=1), however, there was no lactotroph PitNET. Among SF1-lineage tumors, serologically non-functional tumors predominated (79%), while, immunohistochemically, 71.2% were gonadotrophin (FSH/LH)-positive.Tumor grades by the French five-tiered classification system were distributed as follows:grade 1a (58.1%), 1b (17.6%), 2a (16.2%), 2b (7.1%), and 3 (1.0%). Two cases of metastatic corticotroph PitNET were observed: The first case, a 50-year-old female had liver metastasis and experienced tumor recurrence 7 years after his initial diagnosis of PitNET, ultimately dying 9.5 years later. The primary tumor appeared bland, but the metastatic tumor exhibited a high mitotic rate and a Ki-67 index was 48%. The second case involved a 44-year-old man with metastases to the paranasal sinus, liver, and bone. Despite showing initial bland histopathology and a low proliferation index, this tumor displayed aggressive behavior.The patient had a recurrence 1.5 years after diagnosis, with additional metastases emerging 3 years later. He survived for 8.0 years and is currently disease-free following surgery, chemotherapy, and radiotherapy. Conclusion This comprehensive analysis of surgically resected PitNETs using the new WHO5 classification provides valuable insights into the distribution of the subtypes in the surgical cohort. Key findings were the predominant gonadotroph PitNET, the absence of lactotroph PitNET, and the rarity of null cell tumors in surgical cases. The lack of lactotrophs was mainly due to medical treatment. This study highlights the discrepancy between serological and immunohistochemical findings of SF1-lineage PitNETs. While metastatic PitNET cases showed poor prognosis, the predictive value of the French grading system for PitNET requires further validation through extended follow-up.

Background: The 5th edition of WHO classification (WHO5) renamed pituitary adenoma as pituitary neuroendocrine tumor (PitNET), aligning with NET nomenclature from other sites.This study investigated the clinicopathological characteristics of surgically resected PitNET based on the WHO5 classification. Methods: A retrospective analysis was conducted on 210 cases of surgically resected and pathologically confirmed PitNET treated at Seoul National University Hospital from 2021 to 2023. The tumors were graded using the French five-tiered grading system proposed by Trouillas et al. Detailed information on grade 3 metastatic PitNET cases is provided. Results: The cohort’s median age was 53 years (age range: 8–84 years), with a male-to-female ratio of 1:1.1. Mean tumor size was 2.5 cm (range: 0.1–6.5 cm). Macroadenomas predominated (91.9%), followed by microadenoma (6.7%), and giant tumors (1.4%), with 56.2% extending suprasellarly. SF1-lineage PitNET was most prevalent (49.5%), followed by PIT1-lineage (23.3%) and TPIT-lineage (17.1%). Null cell tumors (5.7%) and unclassified plurihormonal PitNET (4.3%) were rare. PIT1-lineage PitNET comprised somatotrophs (47.0%), mature plurihormonal PIT1 lineage tumors (18.4%), thyrotrophs (16.3%), immature PIT1-lineage tumors (16.3%), and acidophilic stem cell tumors (n=1), however, there was no lactotroph PitNET. Among SF1-lineage tumors, serologically non-functional tumors predominated (79%), while, immunohistochemically, 71.2% were gonadotrophin (FSH/LH)-positive.Tumor grades by the French five-tiered classification system were distributed as follows:grade 1a (58.1%), 1b (17.6%), 2a (16.2%), 2b (7.1%), and 3 (1.0%). Two cases of metastatic corticotroph PitNET were observed: The first case, a 50-year-old female had liver metastasis and experienced tumor recurrence 7 years after his initial diagnosis of PitNET, ultimately dying 9.5 years later. The primary tumor appeared bland, but the metastatic tumor exhibited a high mitotic rate and a Ki-67 index was 48%. The second case involved a 44-year-old man with metastases to the paranasal sinus, liver, and bone. Despite showing initial bland histopathology and a low proliferation index, this tumor displayed aggressive behavior.The patient had a recurrence 1.5 years after diagnosis, with additional metastases emerging 3 years later. He survived for 8.0 years and is currently disease-free following surgery, chemotherapy, and radiotherapy. Conclusion This comprehensive analysis of surgically resected PitNETs using the new WHO5 classification provides valuable insights into the distribution of the subtypes in the surgical cohort. Key findings were the predominant gonadotroph PitNET, the absence of lactotroph PitNET, and the rarity of null cell tumors in surgical cases. The lack of lactotrophs was mainly due to medical treatment. This study highlights the discrepancy between serological and immunohistochemical findings of SF1-lineage PitNETs. While metastatic PitNET cases showed poor prognosis, the predictive value of the French grading system for PitNET requires further validation through extended follow-up.

Background: The 5th edition of WHO classification (WHO5) renamed pituitary adenoma as pituitary neuroendocrine tumor (PitNET), aligning with NET nomenclature from other sites.This study investigated the clinicopathological characteristics of surgically resected PitNET based on the WHO5 classification. Methods: A retrospective analysis was conducted on 210 cases of surgically resected and pathologically confirmed PitNET treated at Seoul National University Hospital from 2021 to 2023. The tumors were graded using the French five-tiered grading system proposed by Trouillas et al. Detailed information on grade 3 metastatic PitNET cases is provided. Results: The cohort’s median age was 53 years (age range: 8–84 years), with a male-to-female ratio of 1:1.1. Mean tumor size was 2.5 cm (range: 0.1–6.5 cm). Macroadenomas predominated (91.9%), followed by microadenoma (6.7%), and giant tumors (1.4%), with 56.2% extending suprasellarly. SF1-lineage PitNET was most prevalent (49.5%), followed by PIT1-lineage (23.3%) and TPIT-lineage (17.1%). Null cell tumors (5.7%) and unclassified plurihormonal PitNET (4.3%) were rare. PIT1-lineage PitNET comprised somatotrophs (47.0%), mature plurihormonal PIT1 lineage tumors (18.4%), thyrotrophs (16.3%), immature PIT1-lineage tumors (16.3%), and acidophilic stem cell tumors (n=1), however, there was no lactotroph PitNET. Among SF1-lineage tumors, serologically non-functional tumors predominated (79%), while, immunohistochemically, 71.2% were gonadotrophin (FSH/LH)-positive.Tumor grades by the French five-tiered classification system were distributed as follows:grade 1a (58.1%), 1b (17.6%), 2a (16.2%), 2b (7.1%), and 3 (1.0%). Two cases of metastatic corticotroph PitNET were observed: The first case, a 50-year-old female had liver metastasis and experienced tumor recurrence 7 years after his initial diagnosis of PitNET, ultimately dying 9.5 years later. The primary tumor appeared bland, but the metastatic tumor exhibited a high mitotic rate and a Ki-67 index was 48%. The second case involved a 44-year-old man with metastases to the paranasal sinus, liver, and bone. Despite showing initial bland histopathology and a low proliferation index, this tumor displayed aggressive behavior.The patient had a recurrence 1.5 years after diagnosis, with additional metastases emerging 3 years later. He survived for 8.0 years and is currently disease-free following surgery, chemotherapy, and radiotherapy. Conclusion This comprehensive analysis of surgically resected PitNETs using the new WHO5 classification provides valuable insights into the distribution of the subtypes in the surgical cohort. Key findings were the predominant gonadotroph PitNET, the absence of lactotroph PitNET, and the rarity of null cell tumors in surgical cases. The lack of lactotrophs was mainly due to medical treatment. This study highlights the discrepancy between serological and immunohistochemical findings of SF1-lineage PitNETs. While metastatic PitNET cases showed poor prognosis, the predictive value of the French grading system for PitNET requires further validation through extended follow-up.

Background: The 5th edition of WHO classification (WHO5) renamed pituitary adenoma as pituitary neuroendocrine tumor (PitNET), aligning with NET nomenclature from other sites.This study investigated the clinicopathological characteristics of surgically resected PitNET based on the WHO5 classification. Methods: A retrospective analysis was conducted on 210 cases of surgically resected and pathologically confirmed PitNET treated at Seoul National University Hospital from 2021 to 2023. The tumors were graded using the French five-tiered grading system proposed by Trouillas et al. Detailed information on grade 3 metastatic PitNET cases is provided. Results: The cohort’s median age was 53 years (age range: 8–84 years), with a male-to-female ratio of 1:1.1. Mean tumor size was 2.5 cm (range: 0.1–6.5 cm). Macroadenomas predominated (91.9%), followed by microadenoma (6.7%), and giant tumors (1.4%), with 56.2% extending suprasellarly. SF1-lineage PitNET was most prevalent (49.5%), followed by PIT1-lineage (23.3%) and TPIT-lineage (17.1%). Null cell tumors (5.7%) and unclassified plurihormonal PitNET (4.3%) were rare. PIT1-lineage PitNET comprised somatotrophs (47.0%), mature plurihormonal PIT1 lineage tumors (18.4%), thyrotrophs (16.3%), immature PIT1-lineage tumors (16.3%), and acidophilic stem cell tumors (n=1), however, there was no lactotroph PitNET. Among SF1-lineage tumors, serologically non-functional tumors predominated (79%), while, immunohistochemically, 71.2% were gonadotrophin (FSH/LH)-positive.Tumor grades by the French five-tiered classification system were distributed as follows:grade 1a (58.1%), 1b (17.6%), 2a (16.2%), 2b (7.1%), and 3 (1.0%). Two cases of metastatic corticotroph PitNET were observed: The first case, a 50-year-old female had liver metastasis and experienced tumor recurrence 7 years after his initial diagnosis of PitNET, ultimately dying 9.5 years later. The primary tumor appeared bland, but the metastatic tumor exhibited a high mitotic rate and a Ki-67 index was 48%. The second case involved a 44-year-old man with metastases to the paranasal sinus, liver, and bone. Despite showing initial bland histopathology and a low proliferation index, this tumor displayed aggressive behavior.The patient had a recurrence 1.5 years after diagnosis, with additional metastases emerging 3 years later. He survived for 8.0 years and is currently disease-free following surgery, chemotherapy, and radiotherapy. Conclusion This comprehensive analysis of surgically resected PitNETs using the new WHO5 classification provides valuable insights into the distribution of the subtypes in the surgical cohort. Key findings were the predominant gonadotroph PitNET, the absence of lactotroph PitNET, and the rarity of null cell tumors in surgical cases. The lack of lactotrophs was mainly due to medical treatment. This study highlights the discrepancy between serological and immunohistochemical findings of SF1-lineage PitNETs. While metastatic PitNET cases showed poor prognosis, the predictive value of the French grading system for PitNET requires further validation through extended follow-up.

Iatrogenic skull base injury may occur during sinus surgery, and endoscopic repair is considered the gold standard for treatment. We report a 65-year-old male who experienced an iatrogenic ethmoid roof defect caused by endoscopic sinus surgery, eventually leading to four reoperations of endoscopic repairs. Autologous fascia lata and contralateral nasoseptal flap were mainly utilized for this revision case. Following 29 days of hospitalization, which included absolute bed rest with lumbar drainage for 22 days, there was a gradual improvement in the cerebrospinal fluid (CSF) profile and mental status. Additionally, the patient underwent ventriculoperitoneal shunt placement to address non-obstructive hydrocephalus resulting from meningitis, ultimately allowing him to return to his normal daily life. Critical factors in managing large skull base defects with high-flow CSF leakage include multi-layer reconstruction with fascia lata and a pedicled nasoseptal flap, sufficient control of intracranial pressure with CSF drainage and positioning, and infection control through appropriate antibiotics.

Iatrogenic skull base injury may occur during sinus surgery, and endoscopic repair is considered the gold standard for treatment. We report a 65-year-old male who experienced an iatrogenic ethmoid roof defect caused by endoscopic sinus surgery, eventually leading to four reoperations of endoscopic repairs. Autologous fascia lata and contralateral nasoseptal flap were mainly utilized for this revision case. Following 29 days of hospitalization, which included absolute bed rest with lumbar drainage for 22 days, there was a gradual improvement in the cerebrospinal fluid (CSF) profile and mental status. Additionally, the patient underwent ventriculoperitoneal shunt placement to address non-obstructive hydrocephalus resulting from meningitis, ultimately allowing him to return to his normal daily life. Critical factors in managing large skull base defects with high-flow CSF leakage include multi-layer reconstruction with fascia lata and a pedicled nasoseptal flap, sufficient control of intracranial pressure with CSF drainage and positioning, and infection control through appropriate antibiotics.

Background: To identify a screening tool for obstructive sleep apnea (OSA) and evaluate the effects of endoscopic transsphenoidal surgery on improving OSA in patients with acromegaly. Methods: We prospectively enrolled adults with acromegaly scheduled for endoscopic transsphenoidal surgery. All measurements were conducted when participants were admitted for a baseline work-up for acromegaly before surgery and surveillance approximately 3 to 6 months after surgery. Respiratory event index (REI) was used as a surrogate for apnea-hypopnea index (Trial Registration: NCT03526016). Results: Of the 35 patients with acromegaly (median age, 47 years; 40% men; median body mass index, 24.4 kg/m2), 24 (68.6%) had OSA (REI ≥5/hour), 15 (42.9%) had moderate-to-severe OSA (REI ≥15/hour). At baseline, serum insulin-like growth factor 1 (IGF-1) levels were positively correlated with the REI (ρ=0.53, P=0.001). The sensitivity and negative predictive value of a Snoring, Tiredness, Observed apnea, high blood Pressure-Body mass index, age, Neck circumference, and Gender (STOP-Bang) score ≥ 3 were 93.3% and 87.5%, respectively, detecting moderate-to-severe OSA. Biochemical acromegaly remission was achieved in 32 (91.4%) patients. The median difference in the REI was –9.5/hour (95% confidence interval, –13.3 to –5.3). Half of the 24 patients diagnosed with OSA preoperatively had REI <5/hour postoperatively. In a linear mixed-effects model, changes in the REI across surgery were related to changes in IGF-1 levels. Conclusion The STOP-Bang questionnaire is a reliable tool for OSA among patients with acromegaly. Improvement in OSA severity after surgery is related to decreased IGF-1 levels.

Background: Delayed postoperative hyponatremia (DPH) is the most common cause of readmission after pituitary surgery. In this study, we aimed to evaluate the cutoff values of serum copeptin and determine the optimal timing for copeptin measurement for the prediction of the occurrence of DPH in patients who undergo endoscopic transsphenoidal approach (eTSA) surgery and tumor resection. Methods: This was a prospective observational study of 73 patients who underwent eTSA surgery for pituitary or stalk lesions. Copeptin levels were measured before surgery, 1 hour after extubation, and on postoperative days 1, 2, 7, and 90. Results: Among 73 patients, 23 patients (31.5%) developed DPH. The baseline ratio of copeptin to serum sodium level showed the highest predictive performance (area under the curve [AUROC], 0.699), and its optimal cutoff to maximize Youden’s index was 2.5×10–11, with a sensitivity of 91.3% and negative predictive value of 92.0%. No significant predictors were identified for patients with transient arginine vasopressin (AVP) deficiency. However, for patients without transient AVP deficiency, the copeptin-to-urine osmolarity ratio at baseline demonstrated the highest predictive performance (AUROC, 0.725). An optimal cutoff of 6.5×10–12 maximized Youden’s index, with a sensitivity of 92.9% and a negative predictive value of 94.1%. Conclusion The occurrence of DPH can be predicted using baseline copeptin and its ratio with serum sodium or urine osmolarity only in patients without transient AVP deficiency after pituitary surgery.

Iatrogenic skull base injury may occur during sinus surgery, and endoscopic repair is considered the gold standard for treatment. We report a 65-year-old male who experienced an iatrogenic ethmoid roof defect caused by endoscopic sinus surgery, eventually leading to four reoperations of endoscopic repairs. Autologous fascia lata and contralateral nasoseptal flap were mainly utilized for this revision case. Following 29 days of hospitalization, which included absolute bed rest with lumbar drainage for 22 days, there was a gradual improvement in the cerebrospinal fluid (CSF) profile and mental status. Additionally, the patient underwent ventriculoperitoneal shunt placement to address non-obstructive hydrocephalus resulting from meningitis, ultimately allowing him to return to his normal daily life. Critical factors in managing large skull base defects with high-flow CSF leakage include multi-layer reconstruction with fascia lata and a pedicled nasoseptal flap, sufficient control of intracranial pressure with CSF drainage and positioning, and infection control through appropriate antibiotics.

Background: Olfactory dysfunction is a frequently encountered sensory disorder that increases with aging, assessed magnetic resonance imaging (MRI); however, reference quantitative values for associated anatomical structures have rarely been suggested. The aim of this study was to assess the parameters of the olfactory bulbs (OBs) and olfactory sulcus (OS) in Korean adults according to age, along with their olfactory function. Methods: We retrospectively evaluated 217 consecutive patients (104 men, 113 women;mean age, 52.4 ± 15.6 years) who underwent sellar MRI and olfactory function testing before transsphenoidal approach at a single tertiary center from March 2022 to December 2023. Based on the T2-weighted MRI, we evaluated the quantitative size parameters and morphological features of patients’ OB and OS, along with their olfactory function test scores. We assessed the relationship between OB volume and age in pairwise correlations. Results: The mean OB volume was 45.6 ± 15.3 mm 3 in all patients. The patients’ mean Korean version of the Sniffin’ Sticks (KVSS) test II score was 26.8 ± 4.1. OB volume (P < 0.001), height (P < 0.001), and anteroposterior diameter (APD) (P < 0.001) differed significantly among the different age groups. Reduced OB volume was significantly associated with aging (r = –0.58, P < 0.001) and a decline in olfactory function scores (r = 0.34, P < 0.001). Conclusion Based on MRI, we proposed reference OB and OS values in adults of different age groups, highlighting the reduction in OB parameters, especially height and APD along with volume associated with aging and olfactory decline. These values can be useful for evaluating adult patients undergoing MRI for olfactory dysfunction.