1.Evaluation of Thalassaemia Screening Tests in the Antenatal and Non-Antenatal Populations in Singapore.
Shir Ying LEE ; Eng Soo YAP ; Elaine Yp LEE ; Jia Hui GOH ; Te Chih LIU ; Christina YIP
Annals of the Academy of Medicine, Singapore 2019;48(1):5-15
INTRODUCTION:
Haemoglobinopathy testing is performed for carrier screening and evaluation of microcytic anaemia. We evaluated the effectiveness of thalassaemia screening tests at our institution and suggest ways of improving the testing algorithm.
MATERIALS AND METHODS:
A total of 10,084 non-antenatal and 11,364 antenatal samples with alkaline gel electrophoresis (AGE), capillary electrophoresis (CE), haemoglobin H (HbH) inclusion test, mean corpuscular haemoglobin (MCH) and mean corpuscular volume (MCV) were retrospectively reviewed. A subgroup of 187 samples with genetic testing was correlated with HbH inclusions and MCH/ MCV. The effect of iron deficiency on percentage hemoglobin A2 (HbA2) was studied.
RESULTS:
HbH inclusion test showed low sensitivity of 21.43% for α-thalassaemia mutations but higher sensitivity of 78.95% for deletion. By receiver operating characteristic (ROC) analysis, MCH ≤28 pg or MCV ≤80 fl for non-antenatal samples and MCH ≤27 pg or MCV ≤81 fl for antenatal samples had >98% sensitivity for HbH inclusions. Above these thresholds, the probability that HbH inclusions would be absent was <99% (negative predictive value [NPV] >99%). MCH ≥28 pg had 100% sensitivity (95% CI 95.63%-100%) for α-thalassaemia mutations and 97.68% calculated NPV in the antenatal population. Detection of haemoglobin variants by CE correlated highly with AGE (99.89% sensitivity, 100% specificity). Severe iron deficiency reduced HbA2 in hemoglobin ( <0.001) and α-thalassaemia ( = 0.0035), but not in β-thalassaemia.
CONCLUSION
MCH/MCV thresholds have adequate sensitivity for α-thalassaemia in the antenatal population, and genotyping plays an important role as HbH inclusion test shows low sensitivity. CE without AGE, may be used as initial screening for haemoglobin variants. Our study provides contemporary data to guide thalassaemia screening algorithms in Singapore.
Blood Protein Electrophoresis
;
Electrophoresis, Capillary
;
Erythrocyte Inclusions
;
pathology
;
Erythrocyte Indices
;
Female
;
Genetic Testing
;
Hemoglobin H
;
analysis
;
Humans
;
Male
;
Mass Screening
;
Pregnancy
;
Pregnancy Complications, Hematologic
;
blood
;
diagnosis
;
Retrospective Studies
;
Sensitivity and Specificity
;
Singapore
;
alpha-Thalassemia
;
blood
;
diagnosis
2.Association between High Diffusion-Weighted Imaging-Derived Functional Tumor Burden of Peritoneal Carcinomatosis and Overall Survival in Patients with Advanced Ovarian Carcinoma
He AN ; Jose AU PERUCHO ; Keith WH CHIU ; Edward S HUI ; Mandy MY CHU ; Siew Fei NGU ; Hextan YS NGAN ; Elaine YP LEE
Korean Journal of Radiology 2022;23(5):539-547
Objective:
To investigate the association between functional tumor burden of peritoneal carcinomatosis (PC) derived from diffusion-weighted imaging (DWI) and overall survival in patients with advanced ovarian carcinoma (OC).
Materials and Methods:
This prospective study was approved by the local research ethics committee, and informed consent was obtained. Fifty patients (mean age ± standard deviation, 57 ± 12 years) with stage III–IV OC scheduled for primary or interval debulking surgery (IDS) were recruited between June 2016 and December 2021. DWI (b values: 0, 400, and 800 s/mm2 ) was acquired with a 16-channel phased-array torso coil. The functional PC burden on DWI was derived based on K-means clustering to discard fat, air, and normal tissue. A score similar to the surgical peritoneal cancer index was assigned to each abdominopelvic region, with additional scores assigned to the involvement of critical sites, denoted as the functional peritoneal cancer index (fPCI). The apparent diffusion coefficient (ADC) of the largest lesion was calculated. Patients were dichotomized by immediate surgical outcome into high- and low-risk groups (with and without residual disease, respectively) with subsequent survival analysis using the Kaplan-Meier curve and log-rank test. Multivariable Cox proportional hazards regression was used to evaluate the association between DWI-derived results and overall survival.
Results:
Fifteen (30.0%) patients underwent primary debulking surgery, and 35 (70.0%) patients received neoadjuvant chemotherapy followed by IDS. Complete tumor debulking was achieved in 32 patients. Patients with residual disease after debulking surgery had reduced overall survival (p = 0.043). The fPCI/ADC was negatively associated with overall survival when accounted for clinicopathological information with a hazard ratio of 1.254 for high fPCI/ADC (95% confidence interval, 1.007–1.560; p = 0.043).
Conclusion
A high DWI-derived functional tumor burden was associated with decreased overall survival in patients with advanced OC.