ECP 2022 Abstract Book

Virchows Archiv (2022) 481 (Suppl 1):S1–S364 13 Results: Squamous cell carcinoma of the bladder constitutes 2% to 7% of urothelial cancers. The basaloid variant of squamous cell carcinoma is exceptional in the bladder and only three cases have already been reported in the literature. Histologically, the morphological appearance of basaloid carcinoma of the bladder is identical to that of basaloid carcinomas in other anatomical sites such as the lung. The treatment of this tumour is not specific due to the lack of clinical data; it is essentially based on surgery. The importance of adjuvant treatment with radiotherapy or chemotherapy is unclear. Basaloid carcinoma has a more aggressive clinical course and poorer prognosis than conventional squamous cell carcinoma. Conclusion: Basaloid squamous cell carcinoma of the bladder is a very rare entity with a poor prognosis. The diagnosis of this rare variant is based on histological study. The optimal treatment has yet to be defined due to the limited data available. E-PS-24-008 Expression of glycodelin in the prostate gland in patients with prostate adenocarcinoma P. Vishnyakova*, K. Artem’eva, I. Stepanova, E. Ponomarenko, I. Bogdanova, M. Boltovskaya, E. Goufman, M. Mnikhovich, N. Nizyaeva, L. Mikhaleva *National Medical Research Center for Obstetrics, Gynaecology and Perinatology named after Academician V.I. Kulakov, Russia Background & objectives: Glycodelin (Gd) is expressed in various types of cancer and correlates differently with the diagnosis and prog- nosis. The aim of the study was to evaluate the immunohistochemical expression of Gd in areas of adenocarcinoma, hyperplasia, and intact prostate tissue. Methods: The study included 64 men diagnosed with prostate cancer aged 50 to 79 years. By immunohistochemical (IHC) study using monoclonal mouse antibodies to the peptide part of Gd we evaluate localization and intensity of staining (in points (0-3) in cancerous foci, areas of hypertrophy and areas of normal glandular tissue of the prostate. Results: We have revealed IHC cytoplasmic expression of Gd in prostate tissue, both in normal and pathologically altered areas. The lowest median staining intensity in the cytoplasm of tumour cells was in younger patients aged 50-59 years (0 (0; 1)), in higher degree of cell differentiation ISUP 1 (0 (0; 1)), as well as in the group without metastases (0.5(0; 1.125)). In unchanged areas of the prostate, the lowest median staining intensity was also recorded in groups aged 50-59 years (0.5 (0; 1)) and without metastases (0.5 (0; 1)) Conclusion: In this study, we have shown the expression of Gd in prostate cancer samples for the first time. Low expression of Gd probably characterizes a more favourable course of prostate cancer. This fact can serve as a prerequisite for further research and clarification of the role of Gd in carcinogenesis. Funding: The study was carried out within the framework of State Assignment No. 122030200534-4 E-PS-24-009 Cystic nephroma in a 40-years old female patient with a history of craniopharyngioma. A case report N. Poulianitis*, C. Roumbas, C. Karantzias, I. Nitsios, A. Dimi- triadi, M. Lenos, G. Theodoropoulou, G. Kakiopoulos, K. Ntoumas *Department of Pathology, "G. Gennimatas" General Hospital, Athens, Greece Background & objectives: Cystic nephroma is a rare renal mixed epithelial –stromal tumour. It presents in children, rarely in adults. Herein we present a case of a 40-years-old woman with a history of brain surgery for craniopharyngioma She was also under cortisone therapy. Methods: we received in two parts, left kidney weighting 306gr and measuring 11X6X4cm. On cutting there was a tumour measur- ing 11X5X5 cm extending from the upper pole to the middle of the kidney. There was not a clear capsule. The tumour was multicyctic and the cystic component had a smooth surface. The rest of the kidney was macroscopically normal. Results: Pathological examination revealed a biphasic tumour. The epithelial component was represented by cystic spaces covered by a single (rarelly multiple) layer of flattened or cubical cells without atypia. The epithelial cells were monomorphic, with scant cyto- plasm The stromal component was represented by spindles cells arranged in small fascicles without atypia too. There were neither mitotic activity, nor necrosis. The immunohistochemistry showed positivity for KerAE1/AE3 and Ker34βΕ12, as well as PAX-8. The stromal component was negative for CD34. Conclusion: The diagnosis was : cystic nephroma (adult type). This tumour is a rarely observed tumour. It has a benign course. Partial nephrectomy is an appropriate treatment. Long term follow up is recommended to avoid malignant transformation, local recur- rence, or metastasis. To our knowledge, it is the first such tumour that relates with craniopharyngioma. E-PS-24-010 Significant variation of tumour stage by size in clear cell renal cell carcinoma from a prospective national database with a sub-analysis for causality M. Bonert*, N. Nikzad, I. El-Shinnawy, S. Salama, R. Alaghehban- dan, R.H. Breau, A.A. Lalani, R. Rendon, L. Wood, S. Tanguay, N. Basappa, D. Heng, B. Bhindi, F. Pouliot, L. Lavallée, R. Mallick, A. Kapoor *Pathology, McMaster University, Canada Background & objectives: The Canadian Kidney Cancer informa- tion system (CKCis) is a prospective, fourteen-institution database col- laboration of the Kidney Cancer Research Network of Canada. This study assessed tumour stage by size for clear cell renal cell carcinoma (ccRCC) within the CKCis database. Methods: All ccRCC resections in CKCis database were retrieved and stratified by pathology tumour size (≤4 cm, >4 to ≤7 cm, >7 cm). Each institution’s staged by size criteria (SBSC) rates for different tumour size brackets were assessed and compared via funnel plots. A sub-analysis at one institution reviewed the pathology reports and assessed for possible causes of variation. Results: 4,804 ccRCC resections met inclusion criteria. By size ≤4 cm, >4to≤7 cm and >7 cm were 2,213, 1,418, and 1,172 cases, respectively. For pT1a tumours, the SBSC was 2,030 cases, insti- tutional SBSC rate range was 75-95%, median rate was 90% and there were 3 of 14 outlier institutions outside the 95% confidence interval. For pT1b the numbers were 919, 38-77%, 66% and 4 of 14. For pT2 the numbers were 281, 10-34%, 27% and 3 of 14. The sub-analysis demonstrated insufficient renal sinus sampling and significant provider variation among seven pathologists that each examined >60 ccRCC cases (p<0.05); the pT2 rate for >7cm ccRCCs range was 0-41%. Conclusion: This analysis suggests there is significant variation of the pathologic stage for ccRCC. Literature benchmarks suggest an over-call of pT2. The focused sub-analysis suggests both the grossing and microscopic interpretation can be significant factors in pT2 over-call. pT2 rate for >7 cm ccRCC should be followed S351