ECP 2022 Abstract Book

Virchows Archiv (2022) 481 (Suppl 1):S1–S364 13 Conclusion: EBUS-TBNA is an effective and useful procedure in detecting EPM metastases as well as lung cancer metastases in mediastinal lymph nodes. It should be kept in mind that there may be EPM metastases to this region even in cases with unknown pri- mary, and additional studies will be useful when necessary. PS-11-013 Standardization of p16/ki-67 immunocytochemistry in conven- tional cervical cytology for detection of high-grade cervical squamous intraepithelial lesion A. Pineda, I. Benedetti*, L. Barrios *Universidad de Cartagena, Colombia Background & objectives: Detection of p16/Ki-67 expres- sion increases the cervical liquid based cytology performance to diagnose high-grade squamous intraepithelial lesion (HISL). Scarce studies have evaluated its use in conventional cytology, the screening test used in women <30 years in many Latin American countries. Methods: The implementation of p16/Ki-67 dual staining was evaluated in conventional cervical cytology smears with HSIL, with a corresponding confirmatory biopsy study. Xylene pretreat- ment of the smears was carried out to remove the coverslip, before discoloration, rehydration and antigen retrieval. The dual-staining protocol was followed with different incubation times of the pri- mary antibodies, in areas with morphologically altered cells, previ- ously demarcated. Results: Were included 40 smears with median storage of 233 days. Most of the slides (80%) required a previous time in xylene of two days. There were no statistically significant differences in p16/Ki-67 dual staining in relation to results of conventional cytology, nor with the histopathological diagnosis. Also not in comparison with the slides storage time, the time previously required in xylene, or the incubation time of the primary antibod- ies. Comparing p16/Ki-67 dual staining with cytological results, it was positive in 75% of the cytologies reported as HSIL; regard- ing histopathology, it was observed in 61.5% of the cases with diagnosis of HSIL/CIN2, and in 81.2% of the cases diagnosed as HSIL/CIN3. Conclusion: The p16/Ki-67 dual staining can be performed on archival conventional cervical cytologies with good results. The techniques for the pretreatment of these smears are varied but effective, and for an optimal result the staining protocol should be followed according to the manufacturer recommendations. Considering the wide use of conventional cytology in Latin America, and the scarcity of studies on the usefulness of p16/ Ki-67 dual staining in this type of smears, it is necessary to continue research in this field. Funding: Universidad de Cartagena, Cartagena, Colombia. PS-11-014 Secondary thyroid tumours in fine needle aspiration cytology: Finding the black cat in a coal cellar! I.P. Thayakaran*, T. Patel *Gujarat Cancer and Research Institute, India Background & objectives: Despite the rarity, secondary thyroid tumours(STT) can mimic the commoner primary thyroid tumours chal- lenging the cytopathologist who serves as primary diagnostician in the initial workup of thyroid disease. We aim to review our experience and analyse STT with cytopathologic correlates. Me t hod s : Re t r o s p e c t i ve s t u d y b e t we e n a 1 3 ye a r period(2009-2021). Secondary thyroid tumours were defined as non thyroid-epithelial origin tumours which included either metastasis or direct extension from adjacent organ into thyroid parenchyma. Thirty-three cases of STT were found from archives. Clinical history, age, gender, radiologic and cytologic features were noted. Validation of cytologic diagnosis was made by immunocytochemistry(cell blocks) or on biopsy. Results: The most common site of origin was head and neck(15/33). Age ranged between 4–80 years(median 55) with slight male predilection(M:F ratio 1.6:1). Most presented as a solitary nodule within the thyroid(23/33) with a concomitant primary in the vicinity or distant area. Metastatic disease elsewhere at presentation was seen in majority(17/33). Exclu- sive presentation as carcinoma of unknown primary in thyroid was seen in one-fourth(8/33). None of the cases underwent thyroidectomy. Chemotherapy was used to treat hematopoi- etic neoplasms(8/33). The interval from primary diagnosis to thyroid metastasis varied between 0-6 years. Diagnostic chal- lenges surfaced when distinguishing squamous cell carcinoma from high grade/anaplastic thyroid carcinoma and metastatic adenocarcinoma from follicular thyroid lesions. Conclusion: New f indings from our research include predominance of head and neck squamous cell carcinoma attributable to geographic variation and STT presenting substantially as solitary thyroid mass. Few unusual tumours like langerhans cell histiocytosis, thymic carcinoma and large cell carcinoma were encountered. FNAC is indispensable in diagnostic workup of STT. Distinction between primary versus secondar y thyroid tumour has divergent clinical implications, mandating high precision diagnosis. Thorough clinicoradiologic correlation with cytomorphologic subtleties, use of ancillary techniques(cell block, immunocytochemistry) ensures optimal patient management. PS-11-015 Pathologist-performed palpation-guided fine needle aspiration cytology of head and neck masses including oral lesions: impact on sample adequacy and the importance of obtaining cell blocks for diagnostic accuracy M. Erdal*, F. Aker, Z. Özcan *Haydarpaşa Numune Training and Research Hospital, Turkey Background & objectives: Fine-needle aspiration cytology (FNAC) is a simple, feasible, safe, inexpensive method in diagnostic, surgical, therapeutic approaches to superficial head and neck masses. Here, we share the data from our practice and point at the role of pathologists during FNAC procedure. Methods: A total of 124 FNAC (on 121 patients), were performed without ultrasound guidance in our pathology department by an experienced (25+ years) fine-needle aspiration (FNA) pathologist (*) for palpable masses from January 2015 to March 2022, and were reviewed according to the anatomic location (oral cavity, soft tissues, lymph nodes and salivary glands). Results: Three out of 124 FNACs (2.4%) were non-diagnostic (acellular). 12 (9.7%), 19 (15.3%), 48 (38.7%) and 45 (36.3%) were from the oral cavity, salivary glands, lymph nodes and soft tissue; respectively. A total of 106 cell blocks (85.4%) were obtained. Of these 106 cases; immunohistochemistry was studied in 37 (34.9%), histochemistry in 9 (8.5%) and in situ hybridization in 13 (12.2%). Histological data (follow-up resection specimens and/or cell blocks obtained from FNACs) were obtained in 114 cases (91.9%). S125