Faculty Bibliography

INTRODUCTION/BACKGROUND:The American College of Radiology (ACR) Thyroid Imaging Reporting and Data Systems (TI-RADS) was developed to standardize thyroid ultrasound reports and predict the likelihood of malignancy. In our study, we aimed to correlate indeterminate thyroid fine needle aspiration cytology cases with preceding ultrasound (US) ACR TI-RADS scores and concurrent molecular testing results to examine how well the use of the ACR TI-RADS in our institution predicted which patients with indeterminate cytology might harbor molecular alterations. MATERIALS AND METHODS/METHODS:We performed a retrospective review of thyroid nodules. Patients with US reports that included TI-RADS scores, fine needle aspiration specimens with indeterminate cytology (Bethesda class III-V), and molecular testing results were included. RESULTS:A total of 46 indeterminate cytology cases had had preceding US reports with TI-RADS scores and molecular testing (Bethesda class III, n = 37; Bethesda class IV, n = 6; Bethesda class V, n = 3). Most of the indeterminate cases had had a TI-RADS score of TR4 (31 of 46; 67.39%) or TR5 (9 of 46; 19.57%). RAS mutations were the most common alteration (n = 12). Of the 46 cases, 22 (47.85%) showed no alterations. Ten cases proceeded to surgery, of which seven displayed malignancies. CONCLUSIONS:Molecular testing in cytologically indeterminate thyroid nodules provided valuable information for TR4 and TR5 lesions; however, the TR2 and TR3 lesions often had no molecular alterations. These findings highlight the potential value of including US imaging features when assessing the significance of indeterminate cytology findings.

Follicular dendritic cell sarcomas (FDCS) are rare tumours of lymph nodes and extranodal tissues which are grouped with the histiocytic and dendritic cell neoplasms. The diagnosis is usually made after thorough clinical and pathological examination with immunohistochemical analysis. Difficulties persist in diagnosing FDCS on cytological preparations. We report herein a case of a 57-year-old female who presented with a right neck mass of 5 months duration. Computed Tomography (CT) imaging of the neck reported a necrotic right level IIb lymph node and asymmetric fullness of the right palatine tonsil. Fine needle aspiration (FNA) biopsy revealed numerous spindle, oval and stellate neoplastic cells, arranged singly and in syncytia with moderate nuclear pleomorphism, vesicular chromatin pattern, and prominent nucleoli, sprinkled with small lymphocytes. The tumour cells were strongly diffusely positive for CD21, CD23, and D2-40 immunostaining on cell bock sections, but were negative for CD1a and CD34, supporting the diagnosis of FDCS. Follow-up surgical pathology on the resection showed histopathological features and an immunohistochemical profile consistent with FDCS.

Introduction: Preoperative diagnosis of pancreas ductal adenocarcinoma (PDAC) on endoscopic ultrasound guided fine needle aspiration (FNA) cytology is often required to determine proper therapy. Accurate cytopathology diagnosis on FNA may be challenging due to limited/suboptimal cellularity and gastrointestinal contamination with accurate diagnoses necessitating consideration of the full clinical and radiologic picture in evaluating the pancreatic lesions. In this study, we investigated predictive value of integrating cytology diagnosis, radiologic and clinical features in diagnosing pancreatic adenocarcinoma.
Material(s) and Method(s): Pancreatic FNA cases from 1/2016-12/2018 with >18 months of follow-up or histopathology diagnosis on surgical resection were retrieved (n=203). Cases were categorized as "Adenocarcinoma" or "Benign" according to the surgical resection pathology or clinical follow-up. Their documented serum CA19-9 level, and in-house radiologic reports were studied (n=177, Table 1). A multiplayer perceptron neural network (MNN) was trained and tested for the ability of using the integrated clinical and radiologic features and cytologic diagnosis to distinguish between benign and malignant cases.
Result(s): The sensitivity, specificity, and accuracy for pancreatic FNA cytology alone was 77.5%, 97.6%, and 88.4%, respectively. There were significant correlations between malignant outcome and cytology diagnosis, CA19-9 level and involvement of common bile duct (CBD), pancreatic duct (PD), superior mesenteric artery (SMA) or superior mesenteric vein (SMV) (Table 1, p<0.001). Integration of the cytology diagnosis and CA19-9 level showed 92% accuracy in predicting surgical outcome. The MNN highlighted cytopathology to be the most important factor in predicting pancreatic lesion outcomes, followed by the serum CA19-9 level and involvement of the SMA (Figure 1).
Conclusion(s): Integration of the clinical and radiologic information with cytology diagnosis can improve accuracy in evaluating pancreatic adenocarcinomas, especially in suboptimal FNA cytology specimens. [Formula presented] [Formula presented]
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Introduction: The Paris System classifies polyoma virus cytopathic effect (P-CPE) as "negative for high grade urothelial carcinoma (HGUC)". However, P-CPE may raise false suspicion for HGUC. Conversely, HGUC cells may display considerable degenerative nuclear changes mimicking P-CPE. Thus, P-CPE remains a known source of "atypia" in urine cytology. The aim of our study was to determine the frequency of P-CPE cases reported as atypical urothelial cells (AUC) in our laboratory, and to assess the diagnostic utility of SV40 immunostaining (IHC) in this setting.
Material(s) and Method(s): Urine cytology cases, all processed as single Thin prep (TP) slides, were searched for P-CPE diagnosis from 2018 to 2020. An additional slide was prepared for a subset of 40 randomly selected cases (19 P-CPEs, 21 negative controls) for SV40 IHC validation on TP slides.
Result(s): There were 111 urines with P-CPE. 51% were included in this study (Figure 1). Of these, 25% were diagnosed as negative for HGUC, 72% as AUC, and 3% as suspicious for HGUC. Follow-up histology showed HGUC in 3 (5%) cases (2 with AUC and 1 with suspicious for HGUC presurgical cytology). SV40 IHC was positive in 61.5% of cases in the P-CPE group and negative in 38.5% including one with confirmed HGUC on biopsy (Figure 2). In the control group, SV40 IHC was negative in 88% and equivocal in 12% (Figure 3). The difference in SV40 IHC between the P-CPE and control group was statistically significant (p<0.001).
Conclusion(s): Majority of urine samples with P-CPE were reported as AUC with a very low incidence of confirmed HGUC. SV40 IHC aided in the confirmation of viral infection. Our study shows that once the source of atypia is confirmed as polyoma virus with SV40 IHC, downgrading atypia to negative can safely be accomplished without the concern for missing a high-grade lesion. [Formula presented] [Formula presented] [Formula presented]
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Background: The ASCCP management guidelines recommend that women with an unsatisfactory Pap test (UPT) and negative HPV co-test undergo repeat age-based screening in 2 to 4 months. The rationale is that a negative HPV test in the setting of an UPT may reflect an inadequate sample and therefore should not be interpreted as truly ?negative?. For patients 25 years and older who are co-tested, if HPV is positive for the 16 or 18 genotypes, direct referral for colposcopy is recommended. Our study aimed to determine if a negative HPV co-test result is predictive of the absence of a high grade squamous intraepithelial lesion (HGSIL) and whether these patients may be called back for repeat testing at an interval longer than 2-4 months.
Design(s): Follow up cervical cytology and biopsy results in women with UPT and HPV co-tests between 2017-2019 were collected. Original UPT and HPV co-test results were correlated with follow up Pap and biopsy results.
Result(s): There were 708 UPT cases out of 30,647 total Pap tests (2.3%). Among the 708 UPT cases, 407 had HPV co-testing (57%); 260 (37%) were followed by repeat Pap or biopsy within 2-4 months and 317 (45%) within 12 months. The total follow-up rate was 81%, with a range of 10 days to 18 months. Table 1 depicts follow up information for women with UPT and HPV co-testing. Negative predict values of HPV co-testing for LGSIL and HGSIL detection were 98% and 100%, respectively, while positive predictive values were 43% and 4.7%.
Conclusion(s): A negative HPV co-test in women with an UPT predicted the lack of HGSIL in our study. Compliance with the recommended follow up time of 2-4 months for women with UPT was low at 37%. This may be due to multiple factors, one presumably being the women's reluctance to undergo a repeat pelvic exam due to its uncomfortable nature. Even with a longer follow up time of up to 12 months, there were no HGSILs in the HPV negative group. Our study suggests that women with an UPT and a negative HPV co-test may be safely called back at an interval longer than 2-4 months

BACKGROUND:Ultrasound has become the initial approach to evaluating thyroid nodules, facilitating the distinction between benign and malignant nodules based on composition, echogenicity, nodule border or margin, shape, the presence of calcifications, and nodule dimensions. The American College of Radiology (ACR) recommended the Thyroid Imaging Reporting and Data System (TI-RADS) as a classification system to standardize thyroid ultrasound reports and to predict the probability of malignancy in thyroid nodules using a scoring system (TR1-TR5) based on multiple ultrasound characteristics and nodule size. Fine-needle aspiration (FNA) is recommended as the next step for nodules that warrant further workup. The authors assessed the accuracy of the ACR TI-RADS based on the corresponding FNA cytology results (Bethesda system diagnoses I-VI). METHODS:ACR TI-RADS ultrasound reports and corresponding FNA cytology diagnoses from January 1, 2018 to August 30, 2018 were evaluated. RESULTS:From January 1, 2018 to August 30, 2018, 2306 thyroid ultrasound-guided FNAs were performed at our institution. Of 2306 cases, 361 had ACR TI-RADS reports available. The majority of FNAs were TR4 (180; 49.9%) or TR3 (108; 29.9%). No TR2 or TR3 nodules were associated with Bethesda category V or VI diagnoses. The majority of TR4 nodules (142 of 180; 78.9%) and TR5 nodules (42 of 65; 64.6%) exhibited benign (Bethesda category II) cytology. Fourteen TR5 cases (21.5%) had malignant (Bethesda category VI) cytology. CONCLUSIONS:Although there were no TR2 or TR3 malignant (Bethesda category VI) diagnoses, and there were only a few malignancies in the TR4 and TR5 categories, the current results reassert the notion that the ACR TI-RADS scoring system shows at least some correlation between benign or malignant cytology diagnoses, as illustrated by the greater number of malignant cases in the higher ACR TI-RADS categories.

Introduction: TBS diagnostic category rates, ASCUS/(+)hrHPV (high risk HPV) ratio, and cytotechnologist's (CT'S) concordance with the CP's final diagnosis are used as common quality monitors in gyn cytology. Additionally, extending monitoring of the hrHPV (+) rate to NILM and SIL cases has been proposed as quality indicators for cytopathologist's (CP's) performance. At our institution, Pap tests are finalized without the knowledge of hrHPV status. We investigated the impact of known hrHPV status on CPs' interpretation of cases previously screened as NILM, and stipulated its potential consequence on quality metrics. Material(s) and Method(s): 60 Pap tests previously resulted as NILM, half hrHPV (+) and half hrHPV (-), were reviewed blindly by 5 CPs in two rounds at 4 months interval. At first round, correct hrHPV results were provided to the CPs. At second round, incorrect (reversed) hrHPV results were given. McNemar chi-squared test was used to analyze the impact of knowing the hrHPV test result on Pap test interpretation. Kappa coefficient was calculated to test intra-observer agreement between the first and second review of the same slides for each CP. Result(s): ASCUS (13%) was the most upgraded diagnosis followed by 12 LSILs (2%) and 2 HSILs (0.3%). There were no significant differences in Pap test interpretation based on hrHPV status for 3 CPs and marked differences for 2 CPs (Table 1). Intra-observer agreement between round 1 and round 2 diagnoses varied from moderate to poor (Table 2). Conclusion(s): Knowledge of hrHPV status significantly biases some but not all CPs. hrHPV (+) to NILM, ASCUS and SIL ratios may not be the most objective parameters for evaluation of CP performance under these circumstances. This bias has further implications for CT performance evaluation because it impacts CT discordance rate measured against CPs final diagnosis. [Figure presented] [Figure presented]

Introduction: The Thyroid Imaging Reporting and Data System (TI-RADS) was designed to standardize risk stratification of thyroid nodules by ultrasonographic criteria and categorize nodules as TR1-TR5 to designate nodules for fine needle aspiration (FNA) or surveillance. Thyroid FNAs are classified according to The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) (categories TBS I-VI) with an associated risk of malignancy and management guideline. We utilize Thyroseq-V3 molecular testing for indeterminate cytology cases (TBS III- V). Our aim was to correlate indeterminate thyroid FNAs with TI-RADS scores and molecular results to determine if TI-RADS is accurately identifying nodules for biopsy.
Material(s) and Method(s): A retrospective review of thyroid nodules from 1/1/2018-8/30/2018 was performed. Patients with ultrasound (US) reports including TI-RADS scores, FNA reports with indeterminate cytology (TBS-III, TBS-IV and TBS-V) and molecular testing were included.
Result(s): 370 of 1000 thyroid nodules had US reports with TI-RADS scoring and concurrent cytology. 47 cases had indeterminate cytology (TBS-III n=37, TBS-IV n=7 and TBS-V n=3) and reflex molecular testing. Majority were TR4 (31/47;65.97%) and TR5 (10/47;21.27%) (Table1). 23/47 (48.94%) showed no alteration. NRAS was the most common alteration (8 cases), followed by Copy Number Alterations (CNA) (6 cases) (Figure 1). Three TBS-III cases showed dual alterations (NRAS/CNA x2 and HRAS/CNA). Two TBS-IV cases had multiple alterations (EIF1AX/NRAS/TP53 and NRAS/PTEN).
Conclusion(s): While majority of thyroid nodules had a high TI-RADS score (TR4 or TR5), most cases fell into the atypical category (TBS III). Almost half of the thyroid nodules lacked any molecular alterations thereby suggesting an over-classification by TI-RADS. Further refinement of the TI-RADS criteria may be warranted. [Figure presented] [Figure presented]
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