Additional value of integrated 18F-choline PET/4D contrast-enhanced CT in the localization of hyperfunctioning parathyroid glands and correlation with molecular profile.

PURPOSE: The localization of hyperfunctioning parathyroid gland(s) (HPTG) in patients with primary hyperparathyroidism (PHPT) with negative or inconclusive first-line imaging is a significant challenge. This study aimed to evaluate the role of integrated 18F-choline PET/4D contrast-enhanced computed tomography (4DCeCT) in these patients, compare its detection rate and sensitivity with those of 18F-choline PET/CT and (4DCeCT), and analyse the association between choline metabolism and morphological, biochemical and molecular parameters of HPTG. METHODS: We prospectively enrolled 44 PHPT patients with negative or inconclusive first-line imaging. 18F-Choline PET/CT and 4DCeCT were performed at the same time, and integrated 18F-choline PET/4DCeCT images were obtained after coregistration. Experienced physicians examined the images. The SUVratio and degree of contrast enhancement were recorded for each positive finding. Histopathology, laboratory and multidisciplinary follow-up were used as the standard of reference. Both the detection rates and sensitivities of the three imaging modalities were calculated retrospectively. Immunohistochemistry was performed to evaluate the molecular profile of HPTGs. RESULTS: 18F-Choline PET/4DCeCT was positive in 32 of 44 patients with PHPT (detection rate 72.7%), and 31 of 31 surgically treated patients (sensitivity 100%). These results were significantly (p < 0.05) better than those of 18F-choline PET/CT (56.8% and 80%, respectively) and those of 4DCeCT (54.5 and 74%, respectively). A significant correlation between SUV and calcium level was found. In a multivariate analysis, only calcium level was significantly associated with 18F-choline PET/4DCeCT findings. SUVratio and Ki67 expression were significantly correlated. CONCLUSION: Integrated 18F-choline PET/4DCeCT should be considered as an effective tool to detect PHPT in patients with negative or inconclusive first-line imaging. Choline metabolism is correlated with both calcium level and Ki67 expression in HPTG.

Are there lymphatic vessels in the placenta?

The role of lymphatics in placentation has been scantily studied and the true existence of placental lymphatics is under debate. Numerous blood and lymphatic-lineage molecule markers are now available and they are expressed in human placental tissue. D2-40 expression at the placental stromal level seems to indicate that network-forming, podoplanin-expressing cells may act as a reticular-lymphatic-like conductive network. This exciting area at the intersection of perinatology and lymphology needs further investigation.

Perinatal deaths and lymphatic system involvement: a diagnostic flow-chart applying immunohistochemical methods.

A diagnostic flow chart is presented for use in case of perinatal death or still birth with non-immune hydrops fetalis, visceral effusions, or increased nuchal translucency. Immunohistochemical staining with CD-31, CD-34, D2-40, and smooth muscle actin is recommended.

Selective D2-40 lymphatic endothelium immunoreactivity in developing human fetal skin appendages.

D2-40 is a novel monoclonal antibody that recognizes a 40,000 Da O-linked sialoglycoprotein podoplanin. Although its use is becoming more common, little work has been done with human foetuses. We initiated an evaluation of D2-40 antibody immunoreactivity in developing cutaneous adnexa of human fetuses at various gestational ages. Starting from a retrospective cohort of 1,098 human fetal autopsies we identified and selected a total of 48 fetuses ranging from the 12th week gestational age to term appropriate for this study. We demonstrated that the gems of the hair follicles were D2-40 negative in fetuses from the 12th to 15th week gestation, positive in fetuses between the 16th and 20th week of gestation, negative in fetuses from the 21st week gestation to term. Normal adult controls were also negative. This is the first report to demonstrate intense D2-40 immunoreactivity in the gems of hair follicles of developing human skin.

Immunohistochemical studies in a hydroptic fetus with pulmonary lymphangiectasia and trisomy 21.

This case report presents a hydroptic trisomy 21 fetus affected by lymphatic dysplasia with no other malformations. Our studies using CD31, CD34, smooth muscle actin, desmin, and D2-40 antibodies immunohistochemistry confirm the diagnosis of severe pulmonary lymphangiectasia associated with lymphangiectasia ih the mediastinum and small bowel.