1.HER2 in Metastatic Colorectal Cancer: Diagnostic and Therapeutic Opportunities and Challenges
Zhao-Tao PAN ; Feng-Yu GAI ; Chen CHEN ; Tong LI ; Yan-Ping QING
Progress in Biochemistry and Biophysics 2026;53(4):936-950
Colorectal cancer (CRC) is the third most commonly diagnosed malignancy and the second leading cause of cancer-related mortality worldwide. Despite therapeutic advancements over recent decades, the prognosis for patients with metastatic CRC (mCRC) remains poor. Approximately 2%-4% of mCRC cases exhibit human epidermal growth factor receptor 2 (HER2) amplification or overexpression, defining a distinct molecular subtype. This HER2-positive status is strongly associated with primary resistance to anti-epidermal growth factor receptor (EGFR) therapies, which are the standard of care for patients with RAS wild-type tumors. Beyond its well-established role in breast and gastric cancers, HER2 has emerged as a pivotal biomarker and actionable therapeutic target in mCRC. However, selecting appropriate treatment strategies remains challenging due to patient heterogeneity and diverse molecular subtypes. This review systematically summarizes the molecular biology, diagnostic strategies, and advances in targeted therapies for HER2-positive mCRC. On the diagnostic front, we discuss the applications of immunohistochemistry (IHC), fluorescence in situ hybridization (FISH), next-generation sequencing (NGS), and circulating tumor DNA (ctDNA) detection technologies. We highlight discrepancies in diagnostic criteria across key clinical trials—such as HERACLES, DESTINY, and MOUNTAINEER—underscoring the urgent need for standardized, CRC-specific definitions to ensure consistent patient selection and comparability of efficacy data across studies. Although NGS enables comprehensive genomic profiling, its cost-effectiveness relative to traditional methods must be carefully considered. Therapeutically, we summarize clinical trial data for HER2-directed agents, including tyrosine kinase inhibitors (TKIs) such as tucatinib and lapatinib, monoclonal antibodies like trastuzumab, bispecific antibodies, and antibody-drug conjugates (ADCs) such as trastuzumab deruxtecan. We review dual-targeting strategies and note recent FDA approvals that represent significant milestones in second-line treatment. Additionally, we explore the potential of combining immune checkpoint inhibitors with HER2-targeted therapies to enhance antitumor immunity through mechanisms including antibody-dependent cellular cytotoxicity (ADCC) and modulation of the tumor microenvironment. ADCs enable precise delivery of cytotoxic payloads, reducing off-target toxicity while effectively inhibiting oncogenic pathways. A substantial portion of this review is dedicated to dissecting the molecular mechanisms underlying primary and acquired resistance to HER2-targeted therapies—persistent challenges that limit clinical benefit. These mechanisms include reactivation of downstream signaling pathways such as PI3K/AKT/mTOR and MAPK, concurrent mutations in genes like KRAS or BRAF, and alterations in HER2 expression that compromise treatment efficacy. For instance, specific HER2 mutations (e.g., L755S) can reduce drug binding affinity, while ctDNA monitoring facilitates early detection of emerging resistance clones during disease progression, thereby enabling timely therapeutic adjustments. Tumor heterogeneity and dynamic interactions with the microenvironment further complicate resistance patterns observed in clinical practice. HER2-targeted therapy represents a new frontier in precision oncology for mCRC, offering renewed hope for improving patient outcomes. Realizing this potential will require continued optimization of diagnostic algorithms and treatment workflows. Future efforts must focus on overcoming resistance, validating liquid biopsy approaches for dynamic monitoring, and establishing unified clinical guidelines. HER2 has become an essential biomarker for stratifying mCRC patients beyond traditional RAS and BRAF status, underscoring the shift from empiric treatment to biomarker-driven precision medicine. International, multidisciplinary collaboration will be critical to validate emerging biomarkers and refine treatment algorithms globally.
2.Current status and associated factors of sleep problems among preschool children in Hainan Province
Chinese Journal of School Health 2026;47(4):517-521
Objective:
To understand the current status and associated factors of sleep problems among preschool children in Hainan Province, so as to provide scientific evidence for improving sleep health in this population.
Methods:
From January 2021 to June 2022, a total of 4 105 preschool children aged 3-6 years from 62 kindergartens in Hainan Province were selected using stratified cluster random sampling method. Demographic information and lifestyle habits were collected through the Hainan Province Child Growth and Development Survey Questionnaire. The Children s Sleep Habits Questionnaire (CSHQ) was employed to assess sleep status. Unconditional binary Logistic regression model was applied to investigate the associated factors of sleep problems among preschool children.
Results:
The overall CSHQ score for children was 58.03±18.84, with 80.95% of preschool children exhibiting sleep related issues. The top three most prevalent sleep problem domains were bedtime resistance (72.42%), sleep anxiety ( 54.88 %), and parasomnias (38.86%). Logistic regression analysis revealed that higher family annual income ( OR=0.60, 95%CI = 0.45-0.79), higher maternal education level ( OR=0.53, 95%CI =0.32-0.89), regular or daily vitamin D supplementation ( OR=0.77, 95%CI =0.60-0.99), and fully self initiated eating behavior ( OR=0.71, 95%CI =0.59-0.85) were negatively related with children s sleep problems; in addition, screen exposure ( OR=1.27, 95%CI =1.06-1.51) and picky eating ( OR= 1.47 , 95%CI =1.21-1.78) were positively related to children s sleep problems (all P <0.05).
Conclusion
The high detection rate of sleep problems among preschool children in Hainan Province is multifactorially associated with family environment, dietary habits, and lifestyle behaviors.
3.Noninvasive Screening for Chronic Atrophic Gastritis Using Photoplethysmography-derived Meridian-labelled Harmonic Parameters
Yun-Qing LE ; Jian-Xin CHEN ; Ai-Ping CHEN ; Zhi-Hong LI
Progress in Biochemistry and Biophysics 2026;53(5):1178-1194
ObjectiveChronic atrophic gastritis (CAG) is usually diagnosed by gastroscopy and histopathological biopsy. These procedures remain the reference standard, but their invasive nature and resource requirements may limit their use in large-scale population screening and repeated follow-up. A convenient and reproducible method for noninvasive auxiliary screening may help identify individuals who require further endoscopic assessment. Fingertip photoplethysmography (PPG) provides a noninvasive recording of peripheral pulse waves and allows harmonic features to be extracted from the signal. In this study, the so-called meridian-related variables were defined as PPG-derived harmonic parameters labelled according to meridian nomenclature, rather than as direct measurements of meridian physiology. This study aimed to compare these harmonic parameters between patients with CAG and non-CAG controls, identify parameters that remained different after age adjustment, and develop a multivariable model for noninvasive auxiliary screening and pre-endoscopic risk stratification of CAG. MethodsA total of 343 participants were included, comprising 171 patients with CAG and 172 non-CAG controls. CAG diagnosis was established using gastroscopy and histopathology as the reference standard. Fingertip PPG signals were collected using a PPG-based pulse acquisition device. Eight PPG-derived harmonic parameters labelled according to meridian nomenclature were extracted for analysis. Between-group differences were first assessed using nonparametric tests. Age-adjusted analyses were then performed to reduce potential confounding by age. The false discovery rate (FDR) method was applied for multiple-comparison correction. A multivariable logistic regression model integrating age and multiple harmonic parameters was constructed. Model performance was evaluated using receiver operating characteristic (ROC) analysis and the area under the curve (AUC). Internal validation performance was assessed using stratified five-fold cross-validation and bootstrap optimism correction. Threshold performance was examined using both a high-specificity strategy and a Youden index-based cutoff. Decision curve analysis was used to evaluate the model’s net clinical benefit across a range of threshold probabilities. ResultsAll eight harmonic parameters were non-normally distributed. In the univariate analysis, the stomach-labelled harmonic parameter (ST), bladder-labelled harmonic parameter (BL), and liver-labelled harmonic parameter (LR) differed between the CAG and non-CAG groups. After age adjustment and FDR correction, only ST and BL remained statistically significant. Compared with non-CAG controls, patients with CAG showed higher ST values and lower BL values. This finding indicates an associated differential harmonic pattern that was not fully explained by age distribution. However, the discriminative ability of a single harmonic parameter was limited. The best-performing single indicator was ST, with an AUC of 0.652 (95% CI: 0.595-0.707). The multivariable model integrating age and multiple harmonic parameters achieved an AUC of 0.791 (95% CI: 0.743-0.835), representing an improvement of 0.139 over ST alone. In internal validation, stratified five-fold cross-validation yielded a mean AUC of 0.753 (95% CI: 0.715-0.781), and the bootstrap optimism-corrected AUC was 0.748. These results suggest that the model retained moderate discriminative performance after internal validation.At a specificity of at least 95%, the model achieved a sensitivity of only 40.4% (95% CI: 25.7%-49.7%). This high-specificity cutoff may be suboptimal as the preferred threshold for an initial screening setting because of the potential risk of missed CAG cases. The Youden index-based optimal cutoff was 0.419, corresponding to a sensitivity of 80.7% and a specificity of 62.8%. This threshold may better match the practical aim of noninvasive auxiliary screening, where sensitivity is usually prioritized to reduce missed cases. Decision curve analysis showed that, within a threshold probability range of 10%-55%, the model provided higher net clinical benefit than the reference strategies of recommending gastroscopy for all participants or for none. ConclusionPatients with CAG showed associated harmonic differences in fingertip PPG-derived features, mainly characterized by higher ST and lower BL values after age adjustment and FDR correction. Compared with a single harmonic parameter, the multivariable model showed better overall discrimination and retained moderate internal validation performance. These findings suggest that PPG-derived harmonic parameters labelled according to meridian nomenclature may provide auxiliary information for noninvasive auxiliary screening and front-line triage before gastroscopic confirmation in CAG. The present results support further validation rather than immediate clinical implementation. External validation in independent, multicenter, and preferably prospective screening cohorts is needed to assess the model’s generalizability, screening performance, and potential clinical utility.
4.Noninvasive Screening for Chronic Atrophic Gastritis Using Photoplethysmography-derived Meridian-labelled Harmonic Parameters
Yun-Qing LE ; Jian-Xin CHEN ; Ai-Ping CHEN ; Zhi-Hong LI
Progress in Biochemistry and Biophysics 2026;53(5):1178-1194
ObjectiveChronic atrophic gastritis (CAG) is usually diagnosed by gastroscopy and histopathological biopsy. These procedures remain the reference standard, but their invasive nature and resource requirements may limit their use in large-scale population screening and repeated follow-up. A convenient and reproducible method for noninvasive auxiliary screening may help identify individuals who require further endoscopic assessment. Fingertip photoplethysmography (PPG) provides a noninvasive recording of peripheral pulse waves and allows harmonic features to be extracted from the signal. In this study, the so-called meridian-related variables were defined as PPG-derived harmonic parameters labelled according to meridian nomenclature, rather than as direct measurements of meridian physiology. This study aimed to compare these harmonic parameters between patients with CAG and non-CAG controls, identify parameters that remained different after age adjustment, and develop a multivariable model for noninvasive auxiliary screening and pre-endoscopic risk stratification of CAG. MethodsA total of 343 participants were included, comprising 171 patients with CAG and 172 non-CAG controls. CAG diagnosis was established using gastroscopy and histopathology as the reference standard. Fingertip PPG signals were collected using a PPG-based pulse acquisition device. Eight PPG-derived harmonic parameters labelled according to meridian nomenclature were extracted for analysis. Between-group differences were first assessed using nonparametric tests. Age-adjusted analyses were then performed to reduce potential confounding by age. The false discovery rate (FDR) method was applied for multiple-comparison correction. A multivariable logistic regression model integrating age and multiple harmonic parameters was constructed. Model performance was evaluated using receiver operating characteristic (ROC) analysis and the area under the curve (AUC). Internal validation performance was assessed using stratified five-fold cross-validation and bootstrap optimism correction. Threshold performance was examined using both a high-specificity strategy and a Youden index-based cutoff. Decision curve analysis was used to evaluate the model’s net clinical benefit across a range of threshold probabilities. ResultsAll eight harmonic parameters were non-normally distributed. In the univariate analysis, the stomach-labelled harmonic parameter (ST), bladder-labelled harmonic parameter (BL), and liver-labelled harmonic parameter (LR) differed between the CAG and non-CAG groups. After age adjustment and FDR correction, only ST and BL remained statistically significant. Compared with non-CAG controls, patients with CAG showed higher ST values and lower BL values. This finding indicates an associated differential harmonic pattern that was not fully explained by age distribution. However, the discriminative ability of a single harmonic parameter was limited. The best-performing single indicator was ST, with an AUC of 0.652 (95% CI: 0.595-0.707). The multivariable model integrating age and multiple harmonic parameters achieved an AUC of 0.791 (95% CI: 0.743-0.835), representing an improvement of 0.139 over ST alone. In internal validation, stratified five-fold cross-validation yielded a mean AUC of 0.753 (95% CI: 0.715-0.781), and the bootstrap optimism-corrected AUC was 0.748. These results suggest that the model retained moderate discriminative performance after internal validation.At a specificity of at least 95%, the model achieved a sensitivity of only 40.4% (95% CI: 25.7%-49.7%). This high-specificity cutoff may be suboptimal as the preferred threshold for an initial screening setting because of the potential risk of missed CAG cases. The Youden index-based optimal cutoff was 0.419, corresponding to a sensitivity of 80.7% and a specificity of 62.8%. This threshold may better match the practical aim of noninvasive auxiliary screening, where sensitivity is usually prioritized to reduce missed cases. Decision curve analysis showed that, within a threshold probability range of 10%-55%, the model provided higher net clinical benefit than the reference strategies of recommending gastroscopy for all participants or for none. ConclusionPatients with CAG showed associated harmonic differences in fingertip PPG-derived features, mainly characterized by higher ST and lower BL values after age adjustment and FDR correction. Compared with a single harmonic parameter, the multivariable model showed better overall discrimination and retained moderate internal validation performance. These findings suggest that PPG-derived harmonic parameters labelled according to meridian nomenclature may provide auxiliary information for noninvasive auxiliary screening and front-line triage before gastroscopic confirmation in CAG. The present results support further validation rather than immediate clinical implementation. External validation in independent, multicenter, and preferably prospective screening cohorts is needed to assess the model’s generalizability, screening performance, and potential clinical utility.
5.Epidemiological characteristics of poisonous mushroom-related foodborne disease incidents in Chongqing in 2010-2024
Qing LUO ; Shuquan LUO ; Ping FENG ; Rongsheng FU ; Longfeng CHENG ; Ya WU ; Jingrong CHEN
Journal of Public Health and Preventive Medicine 2026;37(4):36-40
Objective To analyze the epidemiological characteristics of poisonous mushroom-related foodborne disease incidents in Chongqing from 2010 to 2024, and to provide a scientific basis for effective prevention and control of mushroom-related foodborne diseases. Methods Data of poisonous mushroom related foodborne disease incidents reported by the CDCs of 39 districts and counties in Chongqing from 2010 to 2024 were collected, and their epidemic characteristics were analyzed. Results A total of 264 poisonous mushroom poisoning outbreaks were reported in Chongqing from 2010 to 2024, resulting in 1 046 cases of illness, 543 hospitalizations, and 15 deaths, with a mortality rate of 1.43%. The peak of poisoning incidents was from June to October, accounting for 89.02% of the total number of incidents. The top three high-incidence areas were Pengshui Miao Tujia Autonomous County, Dianjiang County, and Nanchuan District. Poisonous mushroom poisoning incidents occurring in household settings, accidental picking and ingestion, and cases involving unidentified mushroom species accounted for 89.02%, 83.33%, and 90.15% of all foodborne disease outbreak incidents, respectively. Conclusion Foodborne disease incidents related to poisonous mushrooms in Chongqing City show an upward trend, and the effectiveness of prevention and control needs to be improved. Based on their seasonal, regional and household clustering characteristics, efforts should be made before the peak season of mushroom poisoning in high-risk areas, targeting key populations with health education, monitoring and early warning, food safety supervision, and medical treatment.
6.Metastatic Extra-Ovarian Steroid Cell Tumor Presenting with Hyperandrogenism and Transaminitis Post Oophorectomy
Preeya Subramaniam ; Vanusha Devaraja ; Goh Qing Ci ; Patricia Lee Siow Ping
Journal of the ASEAN Federation of Endocrine Societies 2026;41(S1):64-65
Introduction:
Steroid cell tumors are rare sex cord-stromal tumors,
accounting for <0.1% of ovarian neoplasms. Extraovarian
steroid cell tumors are exceptionally rare, often androgensecreting, and pose significant diagnostic challenges. Early
recognition is essential to prevent prolonged morbidity
from hyperandrogenism.
Case:
A 60-year-old female, 15 years after total hysterectomy
and bilateral salpingo-oophorectomy for a large ovarian
mass with massive ascites, presented with deranged liver
function tests on routine follow-up. Ultrasonography
and computed tomography imaging revealed multiple
hypervascular lesions in the liver, retroperitoneum,
and peritoneum, suggestive of metastatic disease, with
normal-appearing adrenal glands. Biopsy of a liver lesion
demonstrated a metastatic neoplasm with morphology and
immunoprofile favoring a steroid cell tumor. However,
metastasis from the adrenal cortex or an ovarian primary
could not be excluded.
Given the prior bilateral oophorectomy, metastatic adrenocortical carcinoma was initially suspected, prompting
endocrine evaluation. Further history revealed a 1-year
history of progressive virilization, including increased
facial hair and frontal balding. Hormonal studies
demonstrated elevated testosterone (12.2 mmol/L and
reference range 0.1–1.42) and dehydroepiandrosterone
sulfate (15.9 µmol/L and reference range 0.510–5.560)
and the adrenocorticotropic hormone level of 11.7
pmol/L (reference range 1.60–13.9) with suppressed
gonadotrophins. Additional workup for catecholamine,
cortisol, and aldosterone excess was unremarkable. The discordance between androgen excess and normal adrenal
imaging, despite absent ovarian tissue, suggested an extraadrenal androgen-secreting steroid cell tumor. A second
histopathology review and multidisciplinary discussion
with radiology, gynecologic oncology, and pathology teams
were undertaken. As the disease was deemed inoperable,
repeat retroperitoneal lesion biopsy confirmed metastatic
steroid cell tumor and guided palliative chemotherapy.
She was subsequently referred to gynecologic oncology
for systemic chemotherapy.
Conclusion
Extra-adrenal steroid cell tumors, though rare, should be
considered in patients with hyperandrogenism long after
bilateral oophorectomy, especially when adrenal imaging
is normal. Multidisciplinary evaluation and repeat biopsy
are often crucial for establishing the diagnosis and guiding
treatment.
Hyperandrogenism
;
Ovariectomy
;
Steroids
;
Neoplasms
7.Neither a Friend nor a Foe: An Unusual Case of Severe Symptomatic Hypercalcemia Secondary to Atypical Parathyroid Adenoma
Wye Hong Leong ; Qing Ci Goh ; Vanusha Devaraja Pillai ; Siow Ping Lee ; Maryam Ahmad Sharifuddin
Journal of the ASEAN Federation of Endocrine Societies 2026;41(S1):79-80
Introduction:
Atypical parathyroid adenoma (APA) constitutes approximately 0.5–4.0% of all cases of primary hyperparathyroidism (pHPT). Here, we report a case of APA
presenting with severe hypercalcemia, complicated with
renal impairment, bilateral medullary nephrocalcinosis,
and multiple fragility fractures.
Case:
A 45-year-old male initially presented with a 6-month
history of constipation, polyuria, lethargy, bone pain,
and difficulty in initiating micturition. Laboratory
investigations revealed impaired renal function with
an estimated glomerular filtration rate of 41.4 mL/min,
severe hypercalcemia (4.07 mmol/L), and an elevated
intact parathyroid hormone (iPTH) level of 104.0 pmol/L
(reference range: 1.58–6.03 pmol/L), confirming the
diagnosis of pHPT. He was also found to have vitamin D deficiency, with a serum total 25-hydroxyvitamin D level
of 46 nmol/L.
Ultrasound of the abdomen demonstrated bilateral
medullary nephrocalcinosis, while neck ultrasound and
Tc-99 m sestamibi parathyroid scintigraphy revealed a
concordant lesion in the posterior aspect of the left thyroid
lobe, suggestive of a parathyroid adenoma.
He returned 3 months later with closed fractures of the right
subtrochanteric femur and the right humerus following
a fall from standing height.
In view of persistent hypercalcemia despite hyperhydration and treatment with zoledronic acid, subcutaneous
denosumab (60 mg) was administered, resulting in an
improvement in serum calcium levels. A left inferior
parathyroidectomy was then performed concurrently
with internal fixation of the right femur. The surgery was
uneventful. Histopathological examination confirmed an
atypical parathyroid adenoma. Postoperatively, the serum
calcium and iPTH levels normalized, and the patient
remained asymptomatic and normocalcemic during
regular follow-up.
Conclusion
APA remains a diagnostic and therapeutic challenge due
to its clinical, biochemical, and histopathological features
of equivocal malignancy. Surgical resection remains
the mainstay of management of APA, and long-term
surveillance is essential in view of its uncertain malignant
potential and risk of recurrence.
Hypercalcemia
;
Parathyroid Neoplasms
8.Big and Blurry: Giant Prolactinoma Case Series
Nur Farrah Anima ; Qing Ci Goh ; Vanusha Devaraja Pillai ; Siow Ping Lee
Journal of the ASEAN Federation of Endocrine Societies 2026;41(S1):91-
Introduction:
Giant prolactinomas represent 2–3% of prolactin-secreting
pituitary adenomas and show a male predominance. They
present with mass effect symptoms and hypogonadism, but
may be overlooked, leading to delayed diagnosis. Although
dopamine agonists are first-line therapy, management
remains challenging due to the large size and invasive
behavior. This study aims to describe the clinical and
radiological features, treatment modalities, and outcomes
of three cases of giant prolactinomas. We retrospectively
reviewed three men with giant prolactinomas, including
their clinical, biochemical, and radiological features, along
with treatment and outcomes.
Cases:
Three male patients aged 35–59 years with giant
prolactinomas were included. Two patients presented
with visual disturbances, headache, and features of hypogonadism, while one patient had acute confusion and visual
loss secondary to obstructive hydrocephalus requiring
ventriculoperitoneal shunt insertion. Imaging in all cases
demonstrated large invasive pituitary macroadenomas with
extensive local extension. Baseline serum prolactin levels
were markedly elevated, ranging from 86,568 to 441,116
uIU/mL (86–324 uIU/mL). All patients had secondary
hypogonadism, while secondary hypothyroidism and
hypocortisolism were each identified in two patients.
One patient also had poorly controlled diabetes mellitus
at presentation. Dopamine agonist therapy was initiated
as the primary therapy for all the patients. Two patients
developed cerebrospinal fluid leak following initiation of
low-dose dopamine agonist therapy (one patient received cabergoline 0.25 mg weekly, while another received 0.5 mg
weekly), which resolved spontaneously with conservative
management. Serum prolactin levels decreased markedly,
with significant improvement in symptoms related to
mass effect following treatment.
Conclusion
Giant prolactinomas may present with significant mass
effect and multiple pituitary hormone deficiencies.
Dopamine agonists remain the cornerstone of management
and can result in substantial biochemical and clinical
improvement even in large invasive tumors. However,
rapid tumor shrinkage may lead to complications such
as cerebrospinal fluid leak, highlighting the importance
of close monitoring during treatment initiation.
Prolactinoma
9.AVP Deficiency as the Initial Manifestation of Multisystem Langerhans Cell Histiocytosis: A Diagnostic Odyssey
Yuvaranee Samanaseh ; Vanusha Devaraja ; Goh Qing Ci ; Patricia Lee Siow Ping
Journal of the ASEAN Federation of Endocrine Societies 2026;41(S1):92-
Introduction:
Arginine vasopressin (AVP) deficiency is an uncommon
but important presentation of infiltrative hypothalamic–
pituitary disorders. In adults, isolated AVP deficiency with
pituitary stalk thickening is diagnostically challenging,
especially in the absence of systemic disease. Langerhans
cell histiocytosis (LCH) is a rare cause and may precede
systemic involvement by several years.
Case:
We report a 42-year-old male who presented in 2017 with
polyuria and polydipsia, with urine output of up to 10 L/
day. AVP deficiency was confirmed by the water deprivation
test, and desmopressin was initiated. Initial pituitary
magnetic resonance imaging (MRI) was normal, baseline
anterior pituitary hormonal evaluation was unremarkable, and contrast-enhanced computed tomography (CECT) of
the thorax and abdomen showed no abnormalities.
Repeat pituitary MRI 1 year later demonstrated loss of
the posterior pituitary bright spot with pituitary stalk
thickening. In the absence of systemic involvement, a
presumptive diagnosis of lymphocytic hypophysitis was
made, and pituitary biopsy was deferred due to the high
procedural risk.
Serial pituitary MRIs over the following years showed
persistent infundibular thickening and continued absence
of the posterior pituitary bright spot, without interval
progression or development of additional hormonal
deficiencies. The patient remained clinically stable until
June 2024, when new-onset left hip pain prompted MRI,
revealing a heterogeneous mass involving the femoral
neck and intertrochanteric region with a pathological
fracture. Histopathological examination following wide
resection confirmed LCH, with negative BRAF V600
mutation. Postoperative PET scan revealed a multisystem
disease involving the skeleton, lymph nodes, spine, and
gastrointestinal tract, with no bone marrow involvement.
He subsequently completed six cycles of intravenous
methotrexate and cytarabine.
Conclusion
Adult-onset AVP deficiency may be the earliest
manifestation of occult multisystem Langerhans cell
histiocytosis. This case highlights the importance of longterm follow-up and reconsideration of the initial diagnosis
when new systemic features emerge.
Histiocytosis, Langerhans-Cell
10.Small Lesion, Big Impact: EUS Localization and Ablation of a CT-Occult Insulinoma
Tharshini Indrajothy ; Vanusha Devaraja ; Goh Qing Ci ; Tay Yang Zet ; Patricia Lee Siow Ping
Journal of the ASEAN Federation of Endocrine Societies 2026;41(S1):96-
Introduction:
Insulinoma is a rare functioning pancreatic neuroendocrine
tumor and the most common cause of endogenous
hyperinsulinemic hypoglycemia. Although biochemical
confirmation is usually straightforward, tumor localization may be difficult when lesions are small and not detected
on conventional cross-sectional imaging. In such cases,
endoscopic ultrasound (EUS) plays an important role
in identifying occult lesions and facilitating definitive
treatment.
Case:
A 52-year-old female was admitted in April 2025 with
recurrent seizures secondary to hypoglycemia for 3
years, with increasing frequency over time. She fulfilled
Whipple’s triad, with documented capillary glucose of
1.8 mmol/L during an episode and symptom resolution
following glucose administration. A supervised prolonged
fasting test confirmed endogenous hyperinsulinemic
hypoglycemia, with plasma glucose 1.4 mmol/L, insulin 122
pmol/L, and C-peptide 1,010 pmol/L. Short Synacthen test
demonstrated adequate adrenal reserve. Due to persistent
hypoglycemia, she required high-dose diazoxide.
Contrast-enhanced computed tomography abdomen did
not reveal a pancreatic lesion but incidentally detected a
right ovarian teratoma. She underwent total abdominal
hysterectomy and bilateral salpingo-oophorectomy in
June 2025, with histopathology confirming a mature cystic
teratoma without malignancy. However, hypoglycemic
episodes persisted. Further evaluation with EUS in July
2025 identified a highly vascular isoechoic 8 × 8 mm lesion
in the pancreatic body. Fine-needle biopsy confirmed a
well-differentiated neuroendocrine tumor (WHO grade 1)
with Ki-67 index of 2%. She subsequently underwent EUSguided radiofrequency ablation in August 2025. Follow-up
EUS in December 2025 showed post-ablation change, and
her hypoglycemic episodes resolved completely, allowing
diazoxide to be discontinued.
Conclusion
This case highlights the diagnostic challenge of occult
insulinoma in the presence of negative conventional
imaging. EUS was pivotal for tumor localization and tissue
diagnosis, while EUS-guided radiofrequency ablation
provided effective minimally invasive treatment in a
carefully selected patient.
Insulinoma
;
Tomography, X-Ray Computed


Result Analysis
Print
Save
E-mail