Comparison of plasma-thrombin, HistoGel, and CellGel cell block preparation methods with paired ThinPrep slides in the setting of mediastinal granulomatous disease

Advances in diagnostic liquid-based cytology

Liquid-based cytology (LBC) has changed the landscape of gynaecological cytology. A growing demand exists for LBC in diagnostic cytology, particularly for ancillary testing, such as immunocytochemistry and molecular testing. Ancillary testing solely based on conventional preparation (CP) methods remains challenging. Recently, the increased demand for specialist testing and minimally invasive techniques, such as endoscopic ultrasonography fine-needle aspiration, to obtain cellular samples has led to an increasing demand for ancillary testing on cytology LBC supernatant, slides and cell block (CB). This facilitates the diagnosis and prognosis in cytology samples enabling personalized treatment. An understanding of the history and future prospects of LBC is crucial for its application in routine diagnostics by cytopathologists and cytotechnologists. In this review, we initiated an internet search using the keyword 'liquid-based cytology', and we conducted a literature review to discuss the usefulness of combined diagnosis of LBC and CP, immunocytochemistry and molecular testing and assessed the quality of nucleic acids in diagnostic LBC. High-quality and cell-rich diagnostic LBC surpassed the CP method alone in terms of reliability and versatility of ancillary testing in cytological diagnosis. Conclusively, diagnostic LBC lends itself to various new technologies and is expected to continue evolving with innovations in the future.

[SFE-AFCE-SFMN 2022 consensus on the management of thyroid nodules: Interest and place of thyroid cytology]

The SFE-AFCE-SFMN 2022 consensus deals with the management of thyroid nodules, a symptom that is a frequent reason for consultation in endocrinology. Thyroid nodules are very common and mostly benign. Thyroid ultrasound and thyroid fine-needle aspiration biopsy (FNAB) are the reference tests for the analysis of these nodules. The aim of this article is to describe for the cytopathologist the key points of the SFE-AFCE-SFMN 2022 consensus involving thyroid cytology: the indications for thyroid FNAB, the technique and analysis, and the management (treatment, follow-up) following this cytological screening examination, a key element in the management of the thyroid nodule.

Cell blocks in cytology: review of preparation methods, advantages, and limitations

Cell blocks are cytologic preparations that are processed as paraffin embedded blocks in a manner comparable to formalin-fixed paraffin-embedded tissue in surgical pathology. In addition to serving as an adjunct to other cytologic preparations for morphologic diagnosis, cell blocks play an increasingly important role as they yield tissue sections that can be utilized for ancillary testing such as immunohistochemical stains and molecular studies. While essentially universally viewed as playing a pivotal role in cytopathology practice, there are various factors that limit their use in practice and contribute to dissatisfaction with cell block quality. Cell block preparation, as opposed to tissue processing in surgical pathology, is more variable with many different protocols in use today. This review explores the most commonly used cell block preparation techniques currently in use with review of the unique advantages and limitations each method presents. The goal of this work is to serve as a resource that can aid in making more informed decisions about which cell block protocol may work best for individual laboratories.

A novel method for making cell blocks with higher cellular yield

INTRODUCTION

Cytopathology is an important part of pathology that is used to diagnose disease on the cellular level. The application of the cell block (CB) technique plays a vital role in cytological diagnosis, as blocks and slides can be further used for special stains, immunohistochemistry (IHC), and molecular pathological analysis. Several methods for making CBs have been reported, but their procedures and cellular yield are still deemed unsatisfactory. In this article, we used gellan gum (GG) as an adjuvant for CBs, which resulted in higher cellular yield with simpler procedures.

METHODS

CBs were prepared by using GG, copper sulfate, plasma/thrombin, or pregelatinized starch methods. The procedures of each of these four methods were then compared. CB sections were stained with hematoxylin and eosin (H&E), and the background and morphological features seen by H&E staining were compared. A preliminary IHC and fluorescence in situ hybridization (FISH) study was performed using cytology specimens from eleven and five cases, respectively. The expression of immunocomplex by IHC and the molecular signals detected by FISH were compared in CB sections made by the four methods and a section derived from the biopsy specimen block from the same patient. Feulgen staining, Alcian blue staining, and Masson trichrome staining were performed on the CB sections from 3 cases of pleural fluid. The cellular yield of CB sections from 83 cases according to the four methods was compared using NDP analysis software.

RESULTS

The results demonstrated that sections derived from CBs made with GG had a clear background and good morphological features by H&E staining. The expression of immunocomplex by IHC and the molecular signals of FISH detection in the sections from CBs made by GG were accurately located just as those in biopsy sections from the same patient. The DNA, acidic mucus, and fibrin could be clearly identified through special stains in the CB sections. The procedures involved in the GG method were easily controllable and the coagulated gel increased the ease by which the CB was embedded and sectioned. Specifically, sections from CBs made by the GG method contained higher cellular yield because cells could be concentrated on the bottom of the gel after centrifugation.

CONCLUSION

This novel method for making CBs is a practical, simple method that can result in higher cellular yield. This method is therefore worth promoting in clinical applications.

SFE-AFCE-SFMN 2022 Consensus on the management of thyroid nodules : Recommendations in thyroid cytology: from technique to interpretation

The SFE-AFCE-SFMN 2022 consensus deals with the management of thyroid nodules, a condition that is a frequent reason for consultation in endocrinology. In more than 90% of cases, patients are euthyroid, with benign non-progressive nodules that do not warrant specific treatment. The clinician's objective is to detect malignant thyroid nodules at risk of recurrence and death, toxic nodules responsible for hyperthyroidism or compressive nodules warranting treatment. The diagnosis and treatment of thyroid nodules requires close collaboration between endocrinologists, nuclear medicine physicians and surgeons, but also involves other specialists. Therefore, this consensus statement was established jointly by 3 societies: the French Society of Endocrinology (SFE), French Association of Endocrine Surgery (AFCE) and French Society of Nuclear Medicine (SFMN); the various working groups included experts from other specialties (pathologists, radiologists, pediatricians, biologists, etc.). This section deals with the technique and interpretation of thyroid fine-needle aspiration biopsy (FNAB), a reference test for the analysis of thyroid nodules.

Impact of a Modified HistoGel Method for Processing Endocervical Curettage Specimens on Diagnostic Yield

OBJECTIVES

Endocervical curettage (ECC) specimens may be limited by scant tissue. We evaluated whether a cellular concentration processing method could improve their diagnostic quality.

METHODS

Between October 2018 and June 2019, ECC specimens were assigned chronologically to one of two groups: nonconcentrated ECC (NECC) or concentrated ECC (CECC). NECC specimens underwent routine histologic processing. CECC specimens were processed using a published HistoGel-based cell block method. We reviewed diagnoses for ECCs, concurrent cervical biopsies and/or loop electrosurgical excision procedures (LEEPs), and preceding Papanicolaou (Pap) smears. We performed multivariate logistic regression analyses to evaluate the impact of processing method on ECC adequacy and discordance between Pap smear and worst tissue diagnoses.

RESULTS

NECC and CECC adequacy was 88.2% and 84.7% (P = .06). ECC adequacy was greater if concurrent biopsy/LEEP was performed (odds ratio [OR] = 1.76, P < .01). Discordance between Pap smear and worst tissue diagnoses was 9.5% and 13.3% (P = .04) for cases with NECC and CECC processing, although processing method was not significant in multivariate analysis (OR = 0.74, P = .11). Adequate ECC sampling and concurrent biopsy/LEEP were independently associated with concordance between Pap smear and worst tissue diagnosis (OR = 0.46, P < .01 and OR = 0.65, P = .02).

CONCLUSIONS

ECC processing method did not significantly affect either specimen adequacy (P = .06) or diagnostic discordance (P = .11) when controlled for other factors.