[Salivary gland ultrasound or biopsy? : Comparison of methods based on case examples]

BACKGROUND

Ultrasound examination of the salivary glands (SG) is a quick and noninvasive method to detect and semiquantitatively estimate typical changes in the large SG in Sjögren's syndrome (SS). The differential diagnosis of SS is difficult because several diseases and adverse effects of treatment have a similar clinical picture as SS with sicca syndrome and can even induce alterations in the SG (mimic diseases). Hence, for a long time an SG biopsy was regarded as the diagnostic procedure of choice, especially in SS‑A negative patients, whereas the significance of SD sonography is still controversially discussed.

OBJECTIVE

Comparison of typical and atypical changes for SS in the salivary glands in ultrasound and associated histological sections.

MATERIAL AND METHODS

This article describes six patient cases with antibody positive or negative SS with and without typical SS ultrasound patterns, SS-associated lymphoma, sarcoidosis and IgG4-associated disease. The findings of the sonographic examination of the parotid glands and the associated histology of the SD are explained and put into context.

RESULTS

The SSA antibody positive patients with SS show a typical sonographic pattern with hypoechoic foci, especially if the disease has been present for a long time. This pattern can help support the diagnosis of SS. The ultrasound patterns of the mimic diseases sometimes differ significantly from the typical patterns of pSS. The histological examination of the SG helps to corroborate the diagnosis but low histological focus scores, in particular, require a critical synopsis of the clinical, serological and imaging findings.

CONCLUSION

Both salivary gland ultrasound and the histological examination of SG biopsies are justified in the diagnostics and differential diagnosis of SS and sicca syndrome.

Perioperative cell-free mutant KRAS dynamics in patients with pancreatic cancer

This prospective observational biomarker trial evaluated the diagnostic and prognostic value of circulating KRAS mutations (cmKRAS) and their perioperative dynamics in patients with resectable pancreatic ductal adenocarcinoma (PDAC). Plasma cmKRAS samples (G12D, G12V, G12R, and G12C) were analysed by droplet digital PCR in 51 patients with resectable PDAC, 20 with advanced PDAC, and 34 with non-malignant pancreatic pathology. Preoperative detection of cmKRAS alone did not correlate with poorer overall and disease-free survival in this patient cohort. However, a perioperative change in cmKRAS, particularly accurate when an intraoperative sample was included, was identified as a new and useful marker for prediction of prolonged survival.

Promising biomarker