Staining Pattern of Alcian Blue in Endometrial Cytology: Utility in Distinguishing Grade 1-Endometrial Endometrioid Carcinoma from Endometrial Glandular Stromal Breakdown.

Background and Objective: In endometrial cytology, differentiating endometrial glandular stromal breakdown (EGBD) from endometrial endometrioid carcinoma (G1-EEC) is often difficult. In this study, we provided a new focus on chondroitin sulfate (CS), a major substrate component of the endometrial stroma, and assessed the diagnostic utility of Alcian Blue (AB) staining in the differential diagnosis in liquid-based cytological (LBC) samples. Materials and Methods: LBC specimens from 19 patients with a proliferative endometrium, 36 with EGBD, and 30 with G1-EEC who underwent endometrial cytology were stained with AB (pH 1.0), and their reactivity was observed. In addition, immunocytochemical staining of CS and CD31 was performed for five cases each to evaluate their interrelationship with blood vessels. Results: Regarding the 30 G1-EEC cases, at least one of the three representative staining patterns was observed by AB staining: dot-like, microtubular, and finely branched linear patterns. Moreover, the inner portion of the tubular material observed by AB staining expressed CD31. Conversely, in the 36 EGBD cases, only five metaplastic clusters with irregular protrusions and condensed stromal clusters (CSCs) showed a dot-like positive pattern, and background CSCs did not show reactivity to AB staining in any of the cases. Furthermore, the vascular structure expressing CD31 in cell clusters was also unclear. Conclusions: We demonstrated that AB staining shows different staining patterns in G1-EEC and EGBD, reflecting their different tissue structures. Our data provide new insights into endometrial cell diagnosis changes and demonstrate that AB staining is a potential new diagnostic aid tool for the differentiation of G1-EEC from EGBD.

Multicancer screening test based on the detection of circulating non haematological proliferating atypical cells.

BACKGROUND: the problem in early diagnosis of sporadic cancer is understanding the individual's risk to develop disease. In response to this need, global scientific research is focusing on developing predictive models based on non-invasive screening tests. A tentative solution to the problem may be a cancer screening blood-based test able to discover those cell requirements triggering subclinical and clinical onset latency, at the stage when the cell disorder, i.e. atypical epithelial hyperplasia, is still in a subclinical stage of proliferative dysregulation. METHODS: a well-established procedure to identify proliferating circulating tumor cells was deployed to measure the cell proliferation of circulating non-haematological cells which may suggest tumor pathology. Moreover, the data collected were processed by a supervised machine learning model to make the prediction. RESULTS: the developed test combining circulating non-haematological cell proliferation data and artificial intelligence shows 98.8% of accuracy, 100% sensitivity, and 95% specificity. CONCLUSION: this proof of concept study demonstrates that integration of innovative non invasive methods and predictive-models can be decisive in assessing the health status of an individual, and achieve cutting-edge results in cancer prevention and management.

A review of the directly sampled endometrial cytology on LBC samples: Classification, microscopic criteria and beyond.

The Yokohama System for Reporting Endometrial Cytology (TYS) has been proposed by an expert meeting under the auspices of the International Academy of Cytology (IAC) in May 2016 at the IAC in Yokohama. Since its introduction, the TYS has been receiving worldwide acceptance, and this review aims to assess its global impact. The adoption of endometrial cytology as a diagnostic procedure has been hampered in the past by difficulties arising in interpreting the cellular findings due to a number of factors (such as excess blood, cellular overlapping and the complex physiology of endometrium). Recently, the use of liquid-based cytology (LBC), with its ability to remove blood and mucus and to distribute cells uniformly in a thin layer on the slide, has provided an opportunity to re-evaluate the role of endometrial cytology. LBC is a useful tool in the cytologic diagnosis and follow-up of endometrial abnormalities, which remains complementary to the emerging molecular diagnostic cytopathology. The study of LBC from endometrial cytology could be challenging since it is affected by numerous look-alikes and diagnostic pitfalls. This review discusses these various entities and takes into consideration the ancillary techniques that may be useful in the diagnostic procedure. In conclusion, our review of the published data suggests that the TYS is a valid classification scheme that has been widely accepted by cytopathologists globally, is highly reproducible and makes a valuable contribution to clinical therapeutic management. At present, molecular cytopathology is a rapidly evolving field of modern cytopathology, which underlines the effective interplay between genomics and cytology. This review aims to provide a comprehensive review of the drawbacks of endometrial cytopathology, particularly in terms of endometrial cancer diagnosis and molecular testing.

The Charactex Protocol for Blood-Derived Cytological Preparation of Nonhematological Cancer.

INTRODUCTION: Liquid biopsy, especially when performed by the isolation, expansion, and examination of circulating tumor cells (CTCs) from peripheral blood, has become an innovative and transforming diagnostic tool in Clinical Oncology. The CTCs have already entered the clinical practice as an alternative method to invasive tumor biopsy for detecting postsurgical and/or posttreatment minimal residual disease, to predict cancer recurrence and real-time treatment response. In this context, the retrospective observational project, known as CHARACTEX, has permitted to state that it is possible to exploit blood-based cytologic samples through short-term culture and in vitro CTC expansion. METHODS: This method is based initially on a gradient-sedimentation technique, which impoverishes without completely depriving the obtained sample from the hematological cells, followed by short-term (14 days) in vitro culture and expansion and cytomorphological and flow cytometric analysis to investigate whether the expanded cell population possesses proliferative advantage and fits with criteria, which are consistent to the known primary tumor. RESULTS: The originality of this method is that, apart from the above exposed criteria, there is no selection bias for the isolation of the cells from peripheral blood (like immunomagnetic bead treatment or preliminary immunocytochemistry), which can potentially introduce some limitation to the cell population under evaluation. CONCLUSION: The examination of the expanded cell population obtained by this method is very rewarding for both the pathologist - who can assess multiple tumor-related variables (like immunocytochemistry, flow cytometry of several parameters, and molecular pathology on cell suspensions and cell blocks obtained from them) - and the clinician.

New digital confocal laser microscopy may boost real-time evaluation of endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) from solid pancreatic lesions: Data from an international multicenter study.

BACKGROUND: Pancreatic cancer is an aggressive malignancy and a leading cause of cancer death worldwide; its lethality is partly linked to the difficulty of early diagnosis. Modern devices for endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) were recently developed to improve targeting and sampling of small lesions, but innovative technologies for microscopic assessment are still lacking. Ex vivo fluorescence confocal laser microscopy (FCM) is a new digital tool for real-time microscopic assessment of fresh unfixed biological specimens, avoiding conventional histological slide preparation and potentially being highly appealing for EUS-FNB specimens. METHODS: This study evaluated the possible role of FCM for immediate evaluation of pancreatic specimens from EUS-FNB. It involved comparison of the interobserver agreement between the new method and standard histological analysis during international multicenter sharing of digital images. Digital images from 25 cases of EUS-FNB obtained with real-time FCM technology and 25 paired digital whole-slide images from permanent conventional paraffin sections were observed by 10 pathologists from different Institutions in Europe, Japan, and the United States, in a blinded manner. The study evaluated 500 observations regarding adequacy, morphological clues, diagnostic categories, and final diagnosis. FINDINGS: Statistical analysis showed substantial equivalence in the interobserver agreement among pathologists using the two techniques. There was also good inter-test agreement in determining sample adequacy and when assigning a diagnostic category. Among morphological features, nuclear enlargement was the most reproducible clue, with very good inter-test agreement. INTERPRETATION: Findings in this study are from international multicenter digital sharing and are published here for the first time. Considering the advantages of FCM digital diagnostics in terms of reduced time and unaltered sample maintenance, the ex vivo confocal laser microscopy may effectively improve traditional EUS-FNB diagnostics, with significant implications for planning modern diagnostic workflow for pancreatic tumors. FUNDING: This study was not supported by any funding source.

COVID-19 pandemic impact on cytopathology practice in the post-lockdown period: An international, multicenter study.

BACKGROUND: In a previous worldwide survey, the authors showed a drastic reduction in the number of cytological specimens processed during the coronavirus disease 2019 "lockdown" period along with an increase in malignancy rates. To assess the continued impact of the pandemic on cytological practices around the world, they undertook a second follow-up worldwide survey collecting data from the post-lockdown period (2020). METHODS: Participants were asked to provide data regarding their cytopathology activity during the first 12 weeks of their respective national post-lockdown period (2020), which ranged from April 4 to October 31. Differences between the post-lockdown period and the corresponding 2019 period were evaluated, and the authors specifically focused on rates of malignant diagnoses. RESULTS: A total of 29 respondents from 17 countries worldwide joined the survey. Overall, a lower number of cytological specimens (n = 236,352) were processed in comparison with the same period in 2019 (n = 321,466) for a relative reduction of 26.5%. The overall malignancy rate showed a statistically significant increase (12,442 [5.26%] vs 12,882 [4.01%]; P < .001) during the same time period. Similar results were obtained if both malignancy and suspicious for malignancy rates were considered together (15,759 [6.58%] vs 16,011 [4.98%]; P < .001). CONCLUSIONS: The data showed a persistent reduction in the cytological specimen volume during the post-lockdown period (2020). However, the relative increase in the cytological workload in the late part of the post-lockdown is a promising finding of a slow return to normality.

The expression pattern of CD10 and CD31 identifies fine fibrovascular stroma of grade 1-endometrial endometrioid carcinomas in cytology.

INTRODUCTION: The objective of this study was to assess the diagnostic utility of CD10 in the differential diagnosis of grade 1-endometrial endometrioid carcinoma (G1-EEC) and the metaplastic changes associated with the endometrial glandular and stromal breakdown (EGBD) on liquid-based cytological (LBC) samples. METHODS: (1) The type and distribution of CD10-positive cells in EGBD and G1-EEC patients were evaluated. (2) Based on the results from (1), histological and cytological specimens were double-immunostained with CD31 and CD10 to confirm whether CD10-positive tubular-canalicular material found in (1) was represented by fine threads of endometrial-type fibrovascular stroma. (3) Based on the results from (2), additional immunostaining of histological specimens was performed for CD146 and αSMA as markers of perivascular cells. RESULTS: (1) CD10 positive cells showed two main patterns of expression: cytoplasmic immunoreactivity in the form of dense brown granules in EGBD and tubular-canalicular branching patterns in G1-EEC. (2) The tubular-canalicular material observed in cytological specimens of G1-EEC samples co-expressed CD10 and CD31, and was interpreted as representing fine threads of endometrial fibrovascular stroma in the corresponding histological samples. Conversely, metaplastic changes in EGBD cases, only a few CD31-positive signals were found inside the condensed stromal clusters with CD10-positive. (3) Cells surrounding the CD31-positive vascular endothelial cells expressed CD146 and αSMA; moreover, some of the thin CD10-positive fibrous stromal strands also co-expressed αSMA. CONCLUSIONS: CD10 is a very useful immunomarker for distinguishing between G1-EEC and the metaplastic changes of EGBD in LBC samples.

Cytologic presentation of ovarian large cell carcinoma with rhabdoid features detected on peritoneal washing. Report of one case with cyto-histologic correlation and previously undescribed inactivating SMARCA-4 mutations.

The SMARCA subgroup of genes belongs to the SWI1/SNF1 family, responsible for chromatin remodeling and repair within the nucleosome. The SMARCA4 gene is located on chromosome 19p13 and encodes the BRG1 (BRAhMA) protein. We report the cytological and histological findings in one case of large cell SMARCA4 deficient ovarian carcinoma with positive peritoneal washing in a 69-year-old woman. The neoplastic cells were present as singly lying or perivascular clusters and showed medium or large size, round to oval hyperchromatic nuclei, and scarce to moderate cytoplasms. Molecular pathology investigations performed on the ovarian surgical sample found two previously undescribed mutations in the SMARCA4 gene and additional mutations in the CTNNB1 (Beta Catenin gene) and in PIK3CA. To our knowledge, this case probably represents the third cytologic report of this variant of ovarian carcinoma and the first one with molecular pathologic study.

Nuclear morphometry as an adjunct to cytopathologic examination of endometrial brushings on LBC samples: A prospective approach to combined evaluation in endometrial neoplasms and look alikes.

OBJECTIVE: In this study, we aimed to retrospectively investigate and confirm whether atypical nuclear findings in endometrial cytology are useful when assessed by image morphometry in liquid-based cytology (LBC) and compared with microscopic evaluation. METHODS: In total, 53 cases were selected for this study, including 11 presenting proliferative endometrium, 12 with surface papillary syncytial change with endometrial glandular and stromal breakdown (EGBD-SPSC), 10 endometrioid carcinoma grade 1 (G1-EEC), 10 EEC grade 3 (G3-EEC), and 10 endometrial serous carcinomas (ESC). Nuclear image morphometry for nuclear geometric features (area, grey value, aspect ratio, internuclear distance, nucleolar diameter) was performed using ImageJ computer software. For assessing nucleoli, 3861 nuclei were measured, and for nuclear findings, except for nucleoli, 4036 nuclei were measured in total. RESULTS: (a) Compared with G1-EEC, G3-EEC and ESC presented a marked increase in all six parameters (nuclear enlargement, anisonucleosis, nuclear shade, nuclear shape, irregularity of nuclear arrangement, and nucleolar size). (b) EGBD-SPSC presented a marked increase in two parameters (nuclear shade, nuclear shape) when compared with G1/G3-EEC and ESC. (c) Compared with EGBD-SPSC, EEC and ESC demonstrated a marked increase in nucleolar size (≥2.0 µm). (d) ESC presented a marked increase in nucleolar size (≥3.0 µm) when compared with G3-EEC. CONCLUSIONS: Here we confirmed that atypical nuclear findings evaluated by image morphometry are as useful as microscopic evaluations in endometrial cytology. We believe that the objective evaluation of nucleolar size could contribute to an accurate diagnosis of endometrial-LBC samples.

Global impact of the COVID-19 pandemic on cytopathology practice: Results from an international survey of laboratories in 23 countries.

BACKGROUND: To the authors' knowledge, the impact of the coronavirus disease 2019 (COVID-19) pandemic on cytopathology practices worldwide has not been investigated formally. In the current study, data from 41 respondents from 23 countries were reported. METHODS: Data regarding the activity of each cytopathology laboratory during 4 weeks of COVID-19 lockdown were collected and compared with those obtained during the corresponding period in 2019. The overall number and percentage of exfoliative and fine-needle aspiration cytology samples from each anatomic site were recorded. Differences in the malignancy and suspicious rates between the 2 periods were analyzed using a meta-analytical approach. RESULTS: Overall, the sample volume was lower compared with 2019 (104,319 samples vs 190,225 samples), with an average volume reduction of 45.3% (range, 0.1%-98.0%). The percentage of samples from the cervicovaginal tract, thyroid, and anorectal region was significantly reduced (P < .05). Conversely, the percentage of samples from the urinary tract, serous cavities, breast, lymph nodes, respiratory tract, salivary glands, central nervous system, gastrointestinal tract, pancreas, liver, and biliary tract increased (P < .05). An overall increase of 5.56% (95% CI, 3.77%-7.35%) in the malignancy rate in nongynecological samples during the COVID-19 pandemic was observed. When the suspicious category was included, the overall increase was 6.95% (95% CI, 4.63%-9.27%). CONCLUSIONS: The COVID-19 pandemic resulted in a drastic reduction in the total number of cytology specimens regardless of anatomic site or specimen type. The rate of malignancy increased, reflecting the prioritization of patients with cancer who were considered to be at high risk. Prospective monitoring of the effect of delays in access to health services during the lockdown period is warranted.

Prostatic Ductal Adenocarcinoma with Papillary Features in a Bladder Washing: A Possible Pitfall in Urinary Cytology - Report of One Case.

In this article, we report on a case of combined, acinar and ductal prostatic adenocarcinoma affecting the prostatic urethra, which, due to a low degree of cytologic atypia and an exclusive papillary architecture with visible fibrovascular core, was erroneously diagnosed as a low-grade urothelial carcinoma based on its peculiar cytologic presentation in a bladder washing sample.

Risk of Malignancy (ROM) of Thyroid FNA Diagnosed as Suspicious for Malignancy or Malignant: an Institutional Experience with Systematic Review and Meta-Analysis of Literature.

A universal recommendation does not exist for thyroid FNA suspicious for malignancy (SFM). In this context, the guidelines have estimated a risk of malignancy (ROM) from 50 to 80% and both total thyroidectomy and lobectomy may be indicated. This study aimed to (1) retrospectively evaluate the SFM (i.e., TIR4) in a single institution to estimate their cancer prevalence at histology, and (2) systematic review the literature to obtain more robust information. The study period was 2015-2018. As a major inclusion criterion, both cytology and histology had to be performed in our institution. Histological diagnosis was the gold standard. For the systematic review, the online databases of Google Scholar, PubMed/MEDLINE, and Scopus were searched for papers using the same classification for thyroid FNA. A proportion meta-analysis was performed to obtain the pooled histological cancer rate among TIR4 and TIR5 (random-effects model). In the institutional database, there were 271 nodules with both histology and FNA and the cancer rate of TIR4 was 88.9%. By systematic review, five studies were selected for the meta-analysis. The pooled cancer rate was 85% in TIR4 and 99% in TIR5 (I2 = 0%; no publication bias). In conclusion, these new findings should prompt the guidelines board to fully revise the estimated ROM of SFM category. Clinical thyroidologists and thyroid surgeons should be aware of these data and the patients with SFM should be informed of their ROM.

A Diagnostic Approach to Endometrial Cytology by Means of Liquid-Based Preparations.

The adoption of endometrial cytology as a diagnostic procedure has been hampered in the past by difficulties arising in interpreting the cellular findings due to a number of factors (such as excess blood, cellular overlapping, and the complex physiology of endometrium). Recently, the use of liquid-based cytology (LBC), with its ability to remove blood and mucus and to distribute cells uniformly in a thin layer on the slide, has provided an opportunity to reevaluate the role of endometrial cytology. LBC samples are easier to screen compared to conventional ones, due to a smaller screening area and an excellent quality of cell preparations. LBC by using peculiar cytoarchitectural features is a useful tool in the cellular diagnosis and follow-up of abnormalities, which, however, remains complementary to histopathology and to the emerging molecular diagnostic cytopathology. This review discusses these various entities and takes into consideration the ancillary techniques that may be useful in the diagnostic procedure. Herein, we also summarize the process and rationale by which updates were made to the standardized terminology in 2018 and outline the contents of the new Bethesda-style classification (the Yokohama system) for the endometrial cytology.

Impact of ultrasonographic features, cytomorphology and mutational testing on malignant and indeterminate thyroid nodules on diagnostic accuracy of fine needle cytology samples: A prospective analysis of 141 patients.

OBJECTIVE: Fine needle cytology (FNC) is the first-line diagnostic method to determine the benign or malignant nature of thyroid nodules. The gray zone of cytological classifications remains, however, a crucial and challenging area for cytopathologists. DESIGN, PATIENTS AND MEASUREMENTS: In the present study, 141 thyroid cytological samples, with ultrasonographic suspicious features, have been prospectively analysed. Molecular analyses were performed by an innovative technology using two multiplex PCRs for the amplification of BRAF, N-H-K-RAS and RET exon genes. RNA samples were studied for RET/PTC1 and RET/PTC3 rearrangements by PCR amplification, and the conditions were set-up to study, with a single experiment, both wild-type PAX8 and PAX8/PPARÉ£ rearrangements. In total, 111 samples were examined for BRAF, N-H-KRAS and RET genes. An ultrasonographic, cytological and molecular correlation was also carried out in an attempt to suggest a possible way to manage the patients with thyroid nodules. Cyto-histological correlation was available in 115 cases, and it was used to verify the global diagnostic accuracy of this combined approach. RESULTS: According to the histopathological diagnosis, FNC accuracy was 100% for TIR5 and metastases; 89% for TIR4; 84% for TIR3A and 58% for TIR3B. About 11% of the studied samples showed either RET-PTC1 or RET/PTC3 chromosomal rearrangements, and only one sample simultaneously presented RET/PTC1 and RET/PTC3 rearrangements. PAX8/PPARÉ£ rearrangement was found in 6% of the samples. CONCLUSIONS: A multidisciplinary approach to the thyroid is therefore necessary to develop innovative methods suitable for an improved diagnostic and prognostic definition of thyroid cancer.

Solid papillary thyroid carcinoma with Hashimoto's thyroiditis: description of a further case with challenging cytological features.

Solid papillary thyroid carcinoma (SV-PTC) is a rare variant which is mainly observed in young patients with a history of exposure to ionising radiations. Neoplasms belonging to such category generally carry RET-PTC (REarranged during Transfection- Papillary Thyroid Carcinoma) fusions and seem to have a slightly worse prognosis with respect to classical and follicular variants of papillary thyroid carcinoma (PTC), though consistent prognostic and survival data are scarce. SV-PTC should be differentiated from trabecular-insular poorly differentiated thyroid carcinomas, which occur in a different age group and carry a dismal prognosis. These latter tumours do not show the typical nuclear features of PTC and show tumour necrosis with an high mitotic activity. In this report a further case of SV-PTC is described which was associated to Hashimoto's thyroiditis, a finding never described in the cytological literature up to now for SV-PTC; this association created further differential diagnostic problems. The neoplasm displayed RET-PTC1 fusion.

Insulin-like growth factor-II mRNA-binding protein 3 immunocytochemical expression in direct endometrial brushings: Possible diagnostic help in endometrial cytology.

INTRODUCTION: This study evaluated the immunocytochemical (ICC) expression of IMP3 in direct endometrial brushings processed as liquid-based cytology (LBC) samples of endometrioid adenocarcinoma (EAC), serous carcinoma (ESC) and surface papillary syncytial change (SPSC) with endometrial glandular and stromal breakdown (EGBD) to exploit its possible differential diagnostic aid. METHODS: In total, 333 samples of LBC samples were obtained from selected outpatients in parallel with Pipelle endometrial sampling. They consisted of 97 EAC (83 grade 1: EAC-1, 14 EAC-3), 35 ESC and 201 benign endometrial samples (51 proliferative, 42 secretory, 38 atrophic, 70 SPSC with EGBD). ICC expression of insulin-like growth factor-II mRNA-binding protein 3 (IMP3) was manually performed on Papanicolaou-stained LBC samples. RESULTS: The ESC samples showed positive staining cells in 100%, EAC-3 in 28.5%, and EAC-1 in 2.4% cases. All the benign endometrium samples were negative. Only ESC cases showed strong immunoreactivity (≥3+) in more than 50% of tumour cells with an average frequency of 80%. CONCLUSIONS: IMP3 is a helpful immunomarker to distinguish ESC from EAC and SPSC in endometrial cytology.

Inhibition of Stearoyl-CoA desaturase 1 reverts BRAF and MEK inhibition-induced selection of cancer stem cells in BRAF-mutated melanoma.

BACKGROUND: Combination therapy with BRAF and MEK inhibitors significantly improves survival in BRAF mutated melanoma patients but is unable to prevent disease recurrence due to the emergence of drug resistance. Cancer stem cells (CSCs) have been involved in these long-term treatment failures. We previously reported in lung cancer that CSCs maintenance is due to altered lipid metabolism and dependent upon Stearoyl-CoA-desaturase (SCD1)-mediated upregulation of YAP and TAZ. On this ground, we investigated the role of SCD1 in melanoma CSCs. METHODS: SCD1 gene expression data of melanoma patients were downloaded from TCGA and correlated with disease progression by bioinformatics analysis and confirmed on patient's tissues by qRT-PCR and IHC analyses. The effects of combination of BRAF/MEKi and the SCD1 inhibitor MF-438 were monitored by spheroid-forming and proliferation assays on a panel of BRAF-mutated melanoma cell lines grown in 3D and 2D conditions, respectively. SCD1, YAP/TAZ and stemness markers were evaluated in melanoma cells and tissues by qRT-PCR, WB and Immunofluorescence. RESULTS: We first observed that SCD1 expression increases during melanoma progression. BRAF-mutated melanoma 3D cultures enriched for CSCs overexpressed SCD1 and were more resistant than 2D differentiated cultures to BRAF and MEK inhibitors. We next showed that exposure of BRAF-mutated melanoma cells to MAPK pathway inhibitors enhanced stemness features by upregulating the expression of YAP/TAZ and downstream genes but surprisingly not SCD1. However, SCD1 pharmacological inhibition was able to downregulate YAP/TAZ and to revert at the same time CSC enrichment and resistance to MAPK inhibitors. CONCLUSIONS: Our data underscore the role of SCD1 as prognostic marker in melanoma and promote the use of SCD1 inhibitors in combination with MAPK inhibitors for the control of drug resistance.

Predictivity of clinical, laboratory and imaging findings in diagnostic definition of palpable thyroid nodules. A multicenter prospective study.

PURPOSE: To assess the role of clinical, biochemical, and morphological parameters, as added to cytology, for improving pre-surgical diagnosis of palpable thyroid nodules. METHODS: Patients with a palpable thyroid nodule were eligible if surgical intervention was indicated after a positive or suspicious for malignancy FNAC (TIR 4-5 according to the 2007 Italian SIAPEC-IAP classification), or two inconclusive FNAC at a ≥3 months interval, or a negative FNAC associated with one or more risk factor. Reference standard was histological malignancy diagnosis. Likelihood ratios of malignancy, sensitivity, specificity, negative (NPV), and positive predictive value (PPV) were described. Multiple correspondence analysis (MCA) and logistic regression were applied. RESULTS: Cancer was found in 433/902 (48%) patients. Considering TIR4-5 only as positive cytology, specificity, and PPV were high (94 and 91%) but sensitivity and NPV were low (61 and 72%); conversely, including TIR3 among positive, sensitivity and NPV were higher (88 and 82%) while specificity and PPV decreased (52 and 63%). Ultrasonographic size ≥3 cm was independently associated with benignity among TIR2 cases (OR of malignancy 0.37, 95% CI 0.18-0.78). In TIR3 cases the hard consistency of small nodules was associated with malignity (OR: 3.51, 95% CI 1.84-6.70, p < 0.001), while size alone, irrespective of consistency, was not diagnostically informative. No other significant association was found in TIR2 and TIR3. CONCLUSIONS: The combination of cytology with clinical and ultrasonographic parameters may improve diagnostic definition of palpable thyroid nodules. However, the need for innovative diagnostic tools is still high.

Histologic Outcome of Indeterminate Thyroid Nodules Classified at Low or High Risk.

The revised Italian consensus for the classification and reporting of thyroid cytology (ICCRTC) was published in 2014. Very recently, a high reliability of ICCRTC in classifying low and high risk indeterminate nodules (Tir 3A and Tir 3B, respectively) was demonstrated. This finding prompted us to review our case series of thyroid indeterminate lesions to verify these data. Only lesions undergone FNAC from December 2014 to October 2017 with subsequent histology at our institutions were eligible for the study. All cytologic samples had originally been classified according to ICCRTC in the subcategories of indeterminate lesion, such as Tir 3A and Tir 3B by three cytopathologists and another one with more than 10 years experience, when necessary. Sixty-three indeterminate FNAC were diagnosed during the study period, of which 51 were subsequently surgically treated. Overall, 9 carcinomas (7 follicular and 2 papillary) and 42 benign lesions were found at histology. The cancer rate observed in the Tir 3A category (3/40, 7.5%) was significantly (p = 0.0015) lower than that found in Tir 3B (6/11, 54.5%). No significant differences were found in age and size of the sampled nodules between the two subcategories. We can confirm in our series that the Italian reporting system for thyroid cytology shows high reliability in discriminating low risk indeterminate lesions from those at high risk of malignancy.