Assessment of the localization of chondroitin sulfate in various types of endometrial carcinoma.

INTRODUCTION: This study aimed to assess the localization of chondroitin sulfate (CS), a primary extracellular matrix component, in the stromal region of endometrial carcinoma (EC). METHODS: Immunostaining was performed on 26 endometrial endometrioid carcinoma (EEC) samples of different grades and 10 endometrial serous carcinoma (ESC) samples to evaluate CS localization. This was further confirmed by Alcian Blue (AB) staining as well. RESULTS: In the G1-EEC samples, CS showed reactivity with fibrovascular stroma, supporting closely packed glandular crowding and papillary structures. As the grade increased, the original interstitial structure was re-established, and the localization of CS in the perigulandular region decreased. In the ESC samples, the thick fibrous strands supporting the papillary architecture showed reactivity with CS; however, the delicate stromal region branching into the narrow region showed poor reactivity. The AB staining results showed similar characteristics to the immunostaining ones. CONCLUSIONS: The characteristic localization of CS in various EC types was elucidated. The present study provides new information on endometrial stromal assessment.

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.

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.

Tohoku Medical Megabank Brain Magnetic Resonance Imaging Study: Rationale, Design, and Background.

The Tohoku Medical Megabank Brain Magnetic Resonance Imaging Study (TMM Brain MRI Study) was established to collect multimodal information through neuroimaging and neuropsychological assessments to evaluate the cognitive function and mental health of residents who experienced the Great East Japan Earthquake (GEJE) and associated tsunami. The study also aimed to promote advances in personalized healthcare and medicine related to mental health and cognitive function among the general population. We recruited participants for the first (baseline) survey starting in July 2014, enrolling individuals who were participating in either the TMM Community-Based Cohort Study (TMM CommCohort Study) or the TMM Birth and Three-Generation Cohort Study (TMM BirThree Cohort Study). We collected multiple magnetic resonance imaging (MRI) sequences, including 3D T1-weighted sequences, magnetic resonance angiography (MRA), diffusion tensor imaging (DTI), pseudo-continuous arterial spin labeling (pCASL), and three-dimensional fluid-attenuated inversion recovery (FLAIR) sequences. To assess neuropsychological status, we used both questionnaire- and interview-based rating scales. The former assessments included the Tri-axial Coping Scale, Impact of Event Scale in Japanese, Profile of Mood States, and 15-item Depression, Anxiety, and Stress Scale, whereas the latter assessments included the Mini-Mental State Examination, Japanese version. A total of 12,164 individuals were recruited for the first (baseline) survey, including those unable to complete all assessments. In parallel, we returned the MRI results to the participants and subsequently shared the MRI data through the TMM Biobank. At present, the second (first follow-up) survey of the study started in October 2019 is underway. In this study, we established a large and comprehensive database that included robust neuroimaging data as well as psychological and cognitive assessment data. In combination with genomic and omics data already contained in the TMM Biobank database, these data could provide new insights into the relationships of pathological processes with neuropsychological disorders, including age-related cognitive impairment.

Design and Progress of Child Health Assessments at Community Support Centers in the Birth and Three-Generation Cohort Study of the Tohoku Medical Megabank Project.

The Tohoku Medical Megabank Project (TMM) has been conducting a birth and three-generation cohort study (the BirThree Cohort Study). We recruited 73,529 pregnant women and their family members for this cohort study, which included 23,143 newborns and 9,459 of their siblings. We designed and are in the process of conducting three-step health assessments for each newborn at approximately ages of 5, 10 and 16. These health assessments are administered at seven community support centers. Trained genome medical research coordinators conduct physical examinations of and collect biological specimens from each participant. The Sendai Children's Health Square has been established as the headquarters for these child health assessments and is utilized to accumulate knowledge that can facilitate the proper practice of child health assessments. We designed all the relevant health assessments facilities to allow parents and their children to participate in the health assessments concomitantly. Our centers serve as places where child participants and their parents can feel at ease as a result of the implementation of safety measures and child hospitality measures. The TMM BirThree Cohort Study is in the process of conducting strategically detailed health assessments and genome analysis, which can facilitate studies concerning the gene-environment interactions relevant to noncommunicable diseases. Through these operations, our study allows for a significant depth of data to be collected in terms of the number of biospecimens under study and the comprehensiveness of both basic and clinical data alongside relevant family information.

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.

A study on preserving endometrial glandular architecture during preparation using BD SurePath™ liquid-based cytology reagents: Cellular fixation with preservative fluid requires at least 18 h.

INTRODUCTION: This study aimed to determine the causes of disruption of the three-dimensional architecture of endometrial glands prepared using BD SurePath™ liquid-based cytology (SP-LBC) reagents. One sample preparation method for endometrial cytology is presented in which this three-dimensional architecture can be retained. METHODS: SP-LBC specimens were prepared by the following three methods: (1) using the BD PrepMateTM (PrepMate) System after cellular fixation for 1-6 h (method A); (2) without using the PrepMate System after cellular fixation for 1-6 h (method B); and (3) using the PrepMate System after cellular fixation for at least 18 h (method C). Size and numbers of endometrial cell clusters and numbers of solitary scattered cells were then evaluated. RESULTS: Significantly higher numbers of cell clusters with a major axis of 200 µm or more were yielded by method C (71.3 ± 57.2) than methods A (9.3 ± 5.9, P < 0.001) or B (44.3 ± 28.8, P < 0.05). Method B yielded significantly higher numbers of cell clusters than method A (P < 0.001). Method A (132.2 ± 107.7, p < 0.001) yielded significantly higher numbers of solitary scattered cells than methods B (29.1 ± 14.8) and C (35.7 ± 23.3). No significant difference in solitary cell numbers was found between methods B and C. CONCLUSIONS: Retention of endometrial glandular architecture is rendered possible by allowing sample fixation times of 18 h or more when preparing specimens using the PrepMate System.

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.

Cytopathological evaluation of potential malignancy of duodenal gastrinoma using aspiration smears from two patients' resected tumors (NET G1, NET G2): A case report.

Sporadic gastrin-producing neuroendocrine tumors (NETs) of the duodenum present with either Zollinger-Ellison syndrome or unspecific syndromes. Ki-67 scoring in cytopathology is an alternative approach for establishing the gastrinoma grade. Although the majority of NETs, including gastrinomas, occur in the duodenum, most research regarding the Ki-67 index is focused on tumors of pancreatic origin. To the best of our knowledge, there is no study on the Ki-67 index for cytological analysis of duodenal gastrinoma. The current report presents two cases of a 56-year-old man and a 66-year-old woman with NET G1 and G2 gastrinoma, respectively, arising in the duodenal bulb. The present report focused on the differences in nuclear pleomorphism and Ki-67 index between these two cases.

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.

Evaluation of cellular adequacy in endometrial liquid-based cytology.

OBJECTIVE: This study evaluated cellular adequacy in endometrial liquid-based cytology (LBC) specimens. METHODS: In total, 1267 cases were obtained and the rate of unsatisfactory specimen and diagnostic accuracy for malignancy were assessed. If ≥10 cellular clusters composed of ≤30 endometrial cells were found per specimen, then the sample was provisionally considered adequate. RESULTS: The unsatisfactory rate (with fewer than 10 clusters) was 15.4%. Diagnostic accuracy in specimens with ≥10 clusters was significantly higher (90.5% vs 36.4%) than that in specimens with fewer than10 clusters. Moreover, the unsatisfactory rate in patients aged ≥60 years was significantly higher (33.8% vs 13.2%) than that in patients younger than 60 years. Although the unsatisfactory rate was decreased, significant differences were not found between cases with fewer than five clusters (22.6%) and fewer than 10 clusters (33.8%) in patients aged ≥60 years. Diagnostic accuracy in cases with five or more clusters was significantly higher (90.3% vs 0%) than that in cases with fewer than five clusters. CONCLUSIONS: We propose that ≥10 clusters with ≥30 endometrial cells per cluster could be used as a specimen adequacy criterion for endometrial LBC. If ≥10 clusters cannot be found in patients aged ≥60 years, then the use of the alternative criterion of five or more clusters may yield satisfactory specimen adequacy.

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.

Intraoperative liquid-based cytology of rinsed tissue fragments from head and neck lesions.

BACKGROUND: Intraoperative diagnosis is an essential tool for the rapid diagnostic assessment of clinically critical head and neck lesions. Thus, we assumed that a combination of frozen section histological and cytological diagnoses may be preferable. Here, we investigated a relatively new method called liquid-based cytology of rinsed tissue fragments (LBC-RTF) and compared this method with intraoperative histological diagnosis. METHODS: We used 68 tissue biopsies (9 brains, 8 lymph nodes, 22 salivary glands, and 29 thyroid samples). Samples submitted for intraoperative consultation were divided into two-halves: one was used to prepare frozen sections, and the other was prepared for LBC-RTF by washing with PreservCyt. We then compared the final diagnosis obtained from permanent sections with the intraoperative histological diagnosis based on frozen sections and examination of LBC-RTF preparations. RESULTS: The accuracy of LBC-RTF was higher than that of intraoperative histological diagnosis alone, based on frozen sections of every organ (LBC-RTF: 91.2% vs intraoperative histological diagnosis: 80.9%). With LBC-RTF, artifacts that are commonly observed in frozen sections were not present. In addition, even with challenging cases from which it is impossible to prepare frozen sections, intraoperative diagnosis was possible using the LBC-RTF technique. CONCLUSION: Both histological and cytological intraoperative diagnoses were possible during a surgery if the LBC-RTF technique was used. Moreover, our findings suggest that LBC-RTF improved the diagnostic accuracy of traditional intraoperative diagnosis.

The Yokohama system for reporting directly sampled endometrial cytology: The quest to develop a standardized terminology.

BACKGROUND: The main purpose of directly sampled endometrial cytology is to detect invasive endometrial malignancies. With this principle in mind, The Yokohama System (TYS) Working Group, composed of cytopathologists, surgical pathologists, and gynecologic oncologists met at the 2016 International Congress of Cytology, Yokohama, with the aim to publish a standardized reporting system inclusive of specific diagnostic categories and cytomorphologic criteria for uniform and reliable diagnosis of endometrial malignancies on directly sampled endometrial samples. METHODS: The diagnostic cytopathologic criteria previously published in the literature by the Japanese and Greek working group on endometrial cytology (Yanoh et al. [2012] Acta Cytol. 56:233; Margari et al. [2016] Diagn Cytopathol. 44:888-901) were critically reviewed with the aim of correlating the diagnostic classes to well defined risk categories for endometrial carcinoma (EC). Moreover, two classes of "atypical" endometrial cells were correlated respectively to a low- and high risk group. Some methodological suggestions for the application of ancillary special technologies to liquid based samples were also given. RESULTS: The TYS group conceived a new Bethesda-style classification for directly sampled endometrial cytology which correlates the cytologic diagnostic classes with definite risk categories. The cytomorphologic findings have been correlated to the molecular pathology of EC, also through the application of ancillary special techniques to liquid-based samples. CONCLUSIONS: The success of TYS will depend on the acceptance of TYS by all the relevant pathology and gynecologic oncology communities who, by their joint efforts, will adopt, critically evaluate, and optimize this method with the only aim of further improving the impact of endometrial cytology on patients' care.

Guidelines for cytopathologic diagnosis of epithelioid and mixed type malignant mesothelioma. Complementary statement from the International Mesothelioma Interest Group, also endorsed by the International Academy of Cytology and the Papanicolaou Society of Cytopathology.

To provide practical guidelines for the cytopathologic diagnosis of malignant mesothelioma (MM). Cytopathologists involved in the International Mesothelioma Interest Group (IMIG) and the International Academy of Cytology (IAC), who have an interest in the field contributed to this update. Reference material includes peer-reviewed publications and textbooks. This article is the result of discussions during and after the IMIG 2012 conference in Boston, followed by thorough discussions during the 2013 IAC meeting in Paris. Additional contributions have been obtained from cytopathologists and scientists, who could not attend these meetings, with final discussions and input during the IMIG 2014 conference in cape town. During the previous IMIG biennial meetings, thorough discussions have resulted in published guidelines for the pathologic diagnosis of MM. However, previous recommendations have stated that the diagnosis of MM should be based on histological material only.[12] Accumulating evidence now indicates that the cytological diagnosis of MM supported by ancillary techniques is as reliable as that based on histopathology, although the sensitivity with cytology may be somewhat lower.[345] Recognizing that noninvasive diagnostic modalities benefit both the patient and the health system, future recommendations should include cytology as an accepted method for the diagnosis of this malignancy.[67] The article describes the consensus of opinions of the authors on how cytology together with ancillary testing can be used to establish a reliable diagnosis of MM.

Guidelines for the cytopathologic diagnosis of epithelioid and mixed-type malignant mesothelioma: Complementary Statement from the International Mesothelioma Interest Group, Also Endorsed by the International Academy of Cytology and the Papanicolaou Society of Cytopathology.

OBJECTIVE: To provide practical guidelines for the cytopathologic diagnosis of malignant mesothelioma. DATA SOURCES: Cytopathologists with an interest in the field involved in the International Mesothelioma Interest Group (IMIG) and the International Academy of Cytology (IAC) contributed to this update. Reference material includes peer-reviewed publications and textbooks. RATIONALE: This article is the result of discussions during and after the IMIG 2012 conference in Boston, followed by thorough discussions during the 2013 IAC meeting in Paris. Additional contributions have been obtained from cytopathologists and scientists who could not attend these meetings, with final discussions and input during the IMIG 2014 conference in Cape Town.

Guidelines for the cytopathologic diagnosis of epithelioid and mixed-type malignant mesothelioma. Complementary statement from the International Mesothelioma Interest Group, also endorsed by the International Academy of Cytology and the Papanicolaou Society of Cytopathology.

OBJECTIVE: To provide practical guidelines for the cytopathologic diagnosis of malignant mesothelioma. DATA SOURCES: Cytopathologists with an interest in the field involved in the International Mesothelioma Interest Group (IMIG) and the International Academy of Cytology (IAC) contributed to this update. Reference material includes peer-reviewed publications and textbooks. RATIONALE: This article is the result of discussions during and after the IMIG 2012 conference in Boston, followed by thorough discussions during the 2013 IAC meeting in Paris. Additional contributions have been obtained from cytopathologists and scientists who could not attend these meetings, with final discussions and input during the IMIG 2014 conference in Cape Town.

Value of thyroid specific peroxidase and Ki-67 stains in preoperative cytology for thyroid follicular tumors.

BACKGROUND: The aim of this study was to elucidate immunocytochemically whether thyroid specific peroxidase (TPO) and Ki-67 can complement fine-needle aspiration (FNA) cytology as useful markers in order to distinguish between follicular adenoma (FA) and follicular carcinoma (FC). METHODS: We studied 40 FAs and 68 FCs obtained by surgical resection. FNA cytology smears were divided into two groups: Cytology-A (Cy-A) (94 cases) with typical benign cytology and Cytology-B (Cy-B) (14 cases) with atypical cytology. FCs were divided into two groups: FC-I (42 cases) without any poorly differentiated structures and FC-II (26 cases) with some poorly differentiated structures. Cytology smears and histology from FAs and FCs were studied immunocytochemically for thyroid specific peroxidase (TPO) and Ki-67. RESULTS: TPO expression was negative in 12.5% FAs, 21.4% FC-I, and 46.2% FC-II. In 68 FC cases, Cy-B were more frequently observed in TPO-negative cases (38.1%) than in TPO-positive cases (12.8%). The mean Ki-67 LI was 0.46 in FAs, 0.53 in FC-I, and 1.13 in FC-II. The high Ki-67 LI was correlated with Cy-B. Moreover, higher Ki-67 LI showed a close relationship with distant metastasis. In 94 Cy-A cases, 54 cases were FCs. When 38 cases with negative TPO or Ki-67 LI over 0.62 were extracted from them, as many as 28 cases were FCs, the rate of FCs were significantly higher than the rest. CONCLUSION: Therefore, addition of TPO stain and Ki-67 stain to routine Papanicolaou stain could improve the diagnostic reliability of FNA cytology for FC with high degree of malignancy.