Frozen Section of Parotid Gland Tumours: The Head and Neck Pathologist as a Key Member of the Surgical Team

Frozen Section Analysis in Submandibular Gland Tumors: Optimizing Intraoperative Decision-Making

Introduction: With around 25 different salivary gland tumor entities described by the World Health Organization, the correct preoperative identification of masses as benign or malignant remains a challenge. If preoperative needle biopsy is inconclusive, frozen section analysis is a possible alternative for accurate histological identification. The purpose of our study was to evaluate the diagnostic effectiveness of frozen section performed for primary submandibular gland masses. Methods: In addition to acquiring epidemiological data from patients who underwent submandibular gland excision over a 20-year period, we analyzed the diagnostic effectiveness of frozen section performed for submandibular gland masses. We also examined the impact of frozen section on overall survival. Furthermore, we investigated whether there was an impact on the surgical revision rate for malignant submandibular gland masses that required additional neck dissection within the submandibular triangle. Results: Frozen section was performed for 54 submandibular gland tumors, with a specificity of 100% and a sensitivity of 81.3%. Frozen section was conducted in 12 cases of primary salivary gland malignancies, of which 9 cases were identified correctly. In three cases, the frozen section results were inconclusive. We calculated a relative risk reduction of 27% for revision surgery by performing frozen section. There was no significant association between frozen section results and overall survival. Conclusions: Frozen section demonstrates a significant reduction in the need for revision surgery. With a specificity of 100%, frozen section is especially suited to identifying benign masses. It is a valid diagnostic tool when preoperative sampling is not possible or is inconclusive.

Canalicular-Like Pleomorphic Adenoma of the Parotid Gland: A Recently Classified Tumor Highlighting the Use of Frozen Section Analysis and Surrogate IHC for Gene Rearrangement Defined Subtypes

Canalicular-like pleomorphic adenomas are a relatively recently described entity, that possess features of both canalicular adenomas and pleomorphic adenomas. The presence of unusual HMGA2-fusion partners (most commonly HMGA2::WIF1 gene fusions) has established canalicular-like pleomorphic adenoma as a distinct entity. The use of intraoperative frozen section analysis and surrogate HMGA2 IHC are 2 tools that can provide the surgical team with valuable insight into intraoperative decision making and final classification of rare tumors of the parotid gland, respectively. We present a case of canalicular-like pleomorphic adenoma and characterize its appearance on frozen section analysis. HMGA2 IHC staining was retroactively performed, assisting in the confirmation of the tumor subtype.

Update on Salivary Gland Fine-Needle Aspiration and the Milan System for Reporting Salivary Gland Cytopathology

CONTEXT.—

Fine-needle aspiration (FNA) is a well-established procedure for the diagnosis and management of salivary gland lesions, despite challenges imposed by salivary gland tumor diversity, complexity, and cytomorphologic overlap. Until recently, the reporting of salivary gland FNA specimens was inconsistent among different institutions throughout the world, leading to diagnostic confusion among pathologists and clinicians. In 2015, an international group of pathologists initiated the development of an evidence-based tiered classification system for reporting salivary gland FNA specimens, the Milan System for Reporting Salivary Gland Cytopathology (MSRSGC). The MSRSGC consists of 6 diagnostic categories, which incorporate the morphologic heterogeneity and overlap among various nonneoplastic, benign, and malignant lesions of the salivary glands. In addition, each MSRSGC diagnostic category is associated with a risk of malignancy and management recommendations.

OBJECTIVE.—

To review the current status of salivary gland FNA, core needle biopsies, ancillary studies, and the beneficial role of the MSRSGC in providing a framework for reporting salivary gland lesions and guiding clinical management.

DATA SOURCES.—

Literature review and personal institutional experience.

CONCLUSIONS.—

The main goal of the MSRSGC is to improve communication between cytopathologists and treating clinicians, while also facilitating cytologic-histologic correlation, quality improvement, and research. Since its implementation, the MSRSGC has gained international acceptance as a tool to improve reporting standards and consistency in this complex diagnostic area, and it has been endorsed by the 2021 American Society of Clinical Oncology management guidelines for salivary gland cancer. The large amount of data from published studies using MSRSGC served as a basis for the recent update of the MSRSGC.

Comparing the diagnostic efficacy of optical coherence tomography and frozen section for margin assessment in breast-conserving surgery: a meta-analysis

AIMS

This meta-analysis assessed the relative diagnostic accuracy of optical coherence tomography (OCT) versus frozen section (FS) in evaluating surgical margins during breast-conserving procedures.

METHODS

PubMed and Embase were searched for relevant studies published up to October 2023. The inclusion criteria encompassed studies evaluating the diagnostic accuracy of OCT or FS in patients undergoing breast-conserving surgery. Sensitivity and specificity were analysed using the DerSimonian and Laird method and subsequently transformed through the Freeman-Tukey double inverse sine method.

RESULTS

The meta-analysis encompassed 36 articles, comprising 16 studies on OCT and 20 on FS, involving 10 289 specimens from 8058 patients. The overall sensitivity of OCT was 0.93 (95% CI: 0.90 to 0.96), surpassing that of FS, which was 0.82 (95% CI: 0.71 to 0.92), indicating a significantly higher sensitivity for OCT (p=0.04). Conversely, the overall specificity of OCT was 0.89 (95% CI: 0.83 to 0.94), while FS exhibited a higher specificity at 0.97 (95% CI: 0.95 to 0.99), suggesting a superior specificity for FS (p＜0.01).

CONCLUSIONS

Our meta-analysis reveals that OCT offers superior sensitivity but inferior specificity compared with FS in assessing surgical margins in breast-conserving surgery patients. Further larger well-designed prospective studies are needed, especially those employing a head-to-head comparison design.

PROSPERO REGISTRATION NUMBER

CRD42023483751.

Ability for fine needle aspiration and frozen section to predict extent of parotidectomy

INTRODUCTION

Several diagnostic modalities with various sensitivity and specificities can be used to evaluate a parotid mass. The aims of this project were to compare the diagnostic actionability, accuracy, and ability to accurately predict extent of surgery for FNA and frozen section during the evaluation of a parotid mass.

METHODS

A retrospective chart review of patients who underwent parotidectomy for a parotid mass from January 1, 2015 to January 30, 2022 was conducted. Actionability was defined as a pathology diagnosis or the histologic grade of a lesion, as this provided clear and useful information for the surgeon to act upon. Diagnostic accuracy was determined by comparing FNA and frozen section results to final pathology. Accuracy of extent of surgery was determined by comparing predicted extent of surgery from the FNA or frozen section result to the extent of surgery predicted by the final pathology.

RESULTS

A total of 626 patients were included in this study. FNA was obtained in 396 (63%) patients, while all neoplasms were evaluated by frozen section analysis. FNA diagnosis was actionable in 318 (80%), while frozen section diagnosis was actionable in 616 (98%) patients. Exactly 294 (92.5%) FNA diagnoses were accurate compared with 600 (98%) frozen section diagnoses. The FNA diagnosis predicted appropriate extent of surgery in 294 (74%) while the frozen section diagnosis predicted appropriate extent of surgery in 600 (96%). Among the 396 patients with FNA, frozen section was significantly more likely to accurately predict appropriate extent of surgery compared with FNA (p < 0.001).

CONCLUSION

Frozen section is more likely to yield actionable and accurate results compared with FNA. Additionally, frozen section is better than FNA in predicting the appropriate extent of surgery.

[Results of a nationwide survey on the treatment of salivary gland diseases in German hospitals]

BACKGROUND

Salivary gland diseases are an important part of the work of ENT physicians in hospitals. The treatment strategies depend, among other things, on the doctrine at the respective location.

OBJECTIVE

The aim of this questionnaire-based study was to assess the current diagnostic workup and therapeutic strategies for salivary gland diseases in German otorhinolaryngology departments.

MATERIALS AND METHODS

A survey was performed using a 25-question online questionnaire sent to all German otorhinolaryngology department directors.

RESULTS

The questionnaire was answered by 92 of 175 otorhinolaryngology departments (52.6%). In the diagnosis of salivary gland tumors, a dominance of sonography and MRI was shown. Fine- and core-needle aspiration were not performed by more than 50% of the clinics. The dominant technique for parotidectomy was under microscopic control (82%). In 99% of clinics, EMG was used during resection of the parotid gland for intraoperative monitoring of the facial nerve. There was a trend towards performing partial parotidectomies (85%), lateral parotidectomies (70%), and extracapsular dissections (57%) for benign tumors of the parotid gland. The treatment concepts for malignant tumors were inconsistent.

CONCLUSION

In particular, the treatment strategy and extent of surgery for benign and malignant salivary gland tumors differed depending on location. The choice of palliative (drug) therapy was also diverse. Prospective multicenter studies could help to develop evidence-based treatment strategies.

Assessing the Agreement Between Preoperative Fine-Needle Aspiration Cytology (FNAC) Done for Major Salivary Gland Neoplasm When Reported by Head and Neck Pathologists and Non-head and Neck Pathologists with Its Final Histopathology

The preoperative FNA is an important investigation in the workup of a salivary gland pathology. A preoperative diagnosis is important to plan management and counsel patients accordingly. In this study, we aimed to assess the agreement between the preoperative FNA and the final histopathology report when reported by a head and neck and a non-head and neck pathologist. All patients with major salivary gland neoplasm having undergone a preoperative FNA before surgery from January 2012 to December 2019 at our hospital were included in the study. Analysis was done to check for concordance between head and neck and non-head and neck pathologists of the preoperative FNA and final histopathology. Three hundred and twenty-five patients were included in the study. The preoperative FNA could identify the tumour as benign or malignant in the majority (n = 228, 70.1%). The agreement between the preoperative FNA, frozen section diagnosis and the reporting of grade in the frozen section and the final HPR was slightly better with the head and neck pathologist (kappa = 0.429, kappa = 0.698 and kappa = 0.257), respectively, than with the non-head and neck pathologist (kappa = 0.387, kappa = 0.519 and kappa = 0.158), all of which was statistically significant (p < 0.001). The diagnosis made with the preoperative FNA and reporting in the frozen section had a fair agreement with the final histopathology when reported by a head and neck pathologist in comparison to a non-head and neck pathologist.

Diagnostic accuracy of fine needle aspiration cytology in parotid gland lesions

BACKGROUND

This study aimed to estimate the fine needle aspiration cytology's (FNAC) diagnostic accuracy in differentiating neoplastic from inflammatory lesions (Q1) and malignant from their benign counterparts (Q2).

METHODS

We present a retrospective case series covering a single University Hospital and six attending head and neck surgeons over eight years (January 2011 to July 2017). We concentrated on adults with clinically suspected parotid gland lesions. We offered all patients FNAC biopsy preoperatively, and the final diagnosis was established based on the findings of the final histology. The FNAC and histology results were cross-tabulated in a 2 x 2 contingency table, from which we calculated the diagnostic accuracy, sensitivity, specificity, and positive and negative predictive values.

RESULTS

From 212 consecutive patients reviewed, and after excluding thirteen cases (8 %) of valid but non-diagnostic FNAC, 161 cases (50 females and 111 males) fulfilled set eligibility criteria. The most common diagnosis was Warthin tumors (53 patients, 34 %), followed by pleomorphic adenomas (52 patients, 33.5 %). The sensitivity and specificity of FNAC in differentiating neoplastic from non-neoplastic lesions and in segregating malignant from benign conditions were estimated to be as high as 50 % and 97 %, and 98 % and 93 %, respectively.

CONCLUSION

FNAC is moderately effective in differentiating non-neoplastic from neoplastic disease and highly accurate in selecting malignant lesions from benign ones. Although the lack of FNAC sensitivity can occasionally be problematic, it still comprises a valuable tool in salivary gland surgery. HIPPOKRATIA 2022, 26 (1):25-31.