Current Salivary Glands Biopsy Techniques: A Comprehensive Review

Biopsy is a surgical procedure performed to collect a portion of tissue or organ for diagnostic studies. The aim of the present manuscript is to describe state-of-the-art major and minor salivary gland biopsy techniques and assess the indications and complications of other salivary gland biopsy techniques. A search was performed using the following MeSH terms: biopsy, fine-needle biopsies, image-guided biopsies, frozen sections, and salivary glands disease. A current overview of major and minor salivary glands biopsy techniques was provided. In the oncological field, a comparison was made between the most widely used biopsy method, ultrasound-guided fine-needle aspiration biopsy (US-FNAB), and an alternative method, ultrasound-guided core needle biopsy (US-guided CNB), highlighting the advantages and disadvantages of each. Finally, intra-operative frozen sections (IOFSs) were presented as an additional intraoperative diagnostic method. Minor salivary gland biopsy (MSGB) is the simplest diagnostic method used by clinicians in the diagnosis of inflammatory and autoimmune diseases. In neoplastic lesions, US-FNAB represents the most performed method; however, due to its low diagnostic accuracy for non-neoplastic specimens, US-guided CNB has been introduced as an alternative method.

Milan Interobserver Reproducibility Study (MIRST): Milan System 2018

INTRODUCTION

Prior to the 2018 publication of the Milan System for Reporting Salivary Gland Cytopathology (MSRSGC), a Web-based interobserver study was performed to evaluate MSRSGC reporting categories, identify cytomorphologic features that represent poor sources of agreement, and establish a baseline for future studies.

MATERIAL AND METHODS

Study participants evaluated 75 images chosen from the MSRSGC image set, prior to the release of the Milan Atlas. Images spanned all diagnostic categories including typical and borderline cytomorphology. Participant demographics were collected on level of training, practice patterns, and experience.

RESULTS

A total of 647 persons attempted access to the survey. Of these, 555 correctly answered the qualifying questions. Participants included: 16.5% ASCP Certified Cytotechnologists, 2.8% Specialist Cytotechnologists, 5.8% IAC Certified individuals, 14.3% Anatomic (AP) Certified Pathologists, 38.9% AP and Cytopathology Certified Pathologists, and 15.3% pathology trainees. Length of participant practice varied from 0 to 54 years. In our sample, 43.4% of participants came from academic centers, 17.6% from private hospitals; and 13.3% from commercial/private laboratories. Overall, 42% of respondents agreed with the reference interpretations of salivary gland lesions. The best agreement was seen in cytopathology certified pathologists. Among the MSRSGC categories, best agreement was found in Neoplasm-Benign (58.9%) and Non-Diagnostic (49.2%) categories, followed by Malignant (48.4%). The agreement rates for Salivary Gland Lesion of Uncertain Malignant Potential (SUMP) and Suspicious For Malignancy (SFM) were 23.6% and 22.7%, respectively.

CONCLUSIONS

Similar to the reproducibility studies conducted for gynecologic and urinary cytopathology, the most important factor in diagnostic reproducibility was a priori classification of image difficulty, although people with higher certifications performed better.