Correction to: Virchows Archiv (2020) 477 (Suppl 1):S1–S390

https://doi.org/10.1007/s00428-020-02938-x

In the Abstract entry E-PS-27-066 (page S386) wrong co-authors were listed in the authorship group, “A. Portyanko and O. Chyzhyk” should have been listed and “V. Liabetsky and A. Smalensky” should have been removed and for the Abstract entry E-PS-27-067 (page S386), the funding information has been added. The correct Abstract are presented as follows

E-PS-27-066

A case of melanoma metastatic to urinary bladder

M. Puchinskaya*, T. Liatkouskaya, A. Portyanko, O. Chyzhyk, I. Masansky

*Minsk City Clinical Oncologic Dispensary, Belarus

Background & objectives: Melanoma is an aggressive malignancy known to widely metastasize to different sites. Metastases to mucosa are rare and such cases are often difficult to differentiate from primary melanomas or primary cancers of the corresponding organ.

Methods: Patient A., male, born 1945, was treated four times for cutaneous lesions (1996 – keratopapilloma, 1999 and 2004 – basal cell cancer, 2009 – trichoepithelioma). In 2010 a skin lesion clinically suspicious of melanoma was seen in the coronal region but after histological examination of the resected tumour sebaceous glands adenoma was diagnosed.

Results: In June 2011 the patient was admitted to oncourology department with macrohaematuria and bladder tumour was removed, histologically urothelial carcinoma grade III. In July 2012 right humerus bone metastasis was diagnosed. A subcutaneous lesion of the neck was found withmalignant cells suspicious ofmelanoma on cytological examination. In core needle biopsy in December 2012 from supraclavicular lymph node urothelial carcinoma was diagnosed. As clinical data (one and lymph node metastases, non-muscular invasive bladder cancer) and histological data were controversial, histologic preparations were re-evaluated. Solid clear cell tumour with brown pigment in some cells, positive for vimentin and S100, was seen in skin, bladder and neck lesions, consistent with melanoma.

Conclusion: The presented case shows that melanoma metastases to urinary bladder are very difficult to diagnose due to rarity of such lesions.

E-PS-27-067

Ratio of membranous and cytoplasmic vimentin expression in prostate cancer M. Puchinskaya* *Minsk City Clinical Oncologic Dispensary, Belarus

Background & objectives: Vimentin is a marker of epithelial-mesenchymal transition (EMT) in various cancers. Cell surface vimentin was shown to mark cells with features of cancer stem cells (CSCs) irrespective of other CSC markers. We assessed ratio of Vim cytoplasmic and membranous expression.

Methods: 36 samples of prostate cancer (PCa) were stained immunohistochemically with rabbit polyclonal antibodies to Vim (ThermoFischer Scientific, 1:1000). Staining was assessed semiquantitatively using a light microscope, x200 magnification. Weighed staining index (WSI), taking into account the percentage of stained cells and the relative amounts of weak, moderate and strong staining, was used for separate membranous and cytoplasmic staining evaluation.

Results: 23 (63.9%) cases were stage pT3, 14 (38.9%) Gleason score 7 (4+3) or 8-10. Membranous vimentin staining was present in 29 (80.6%) cases, cytoplasmic – in 35 (97.2%). Among them in 0 and 3 (8.3%) cases membranous staining was more prevalent than cytoplasmic according to percentage of stained cells (in 5 (13.9%) cases equal scores) and WSI, respectively. In most cases the percentage of cells with membranous staining was much lower, but staining intensities were higher, than for cytoplasmic staining. No statistically significant correlations were found between prevalence of membranous staining and disease pT category, Gleason score or previous neoadjuvant hormonal therapy, this may be due to a small sample size.

Conclusion: Vimentin is mostly expressed in cytoplasm, but membranous staining can also be seen in practically all cases, mostly in a small proportion of cells. These cells with membranous expression may correspond to cells with CSC features, but this hypothesis needs further evaluation using conventional CSC markers or functional assays. Anyway, neoexpression of vimentin shows EMT in most PCa cases.

Funding: The study was funded by Belarusian republican foundation for fundamental research, grant No. M19M-123.