Reproducibility of Histopathological Diagnosis of Urinary Bladder Neoplasms on Microphotographs

Abstract

Introduction: Diagnostic reproducibility and accuracy in pathology are the main issues in oncology screening of various malignancies. Urothelial carcinoma accounts for majority of bladder cancers in the industrialised nations. The reproducibility of histopathological features of different WHO grading systems has shown considerable variation. Aim: To evaluate the reproducibility of histopathological features of urinary bladder neoplasms (categorised according to WHO 2016 classification) on microphotographs. Materials And Methods: This was a retrospective observational study of urinary bladder neoplasms conducted at a rural tertiary care referral Institute, PES Institute of Medical Sciences (PESIMSR), Kuppam, Andhra Pradesh, India, from January 2017 to December 2019 for a period of three years. Histopathology slides of urinary bladder neoplasms were retrieved and reviewed. The urinary bladder neoplasms were categorised according to WHO 2016 classification. Representative images of the neoplasm were captured by 13 megapixels primary mobile camera and sent to two pathologists by e-mail. The histopathological characteristics of the lesions were evaluated. Concordance was calculated. The strength of agreement was analysed by Kappa statistics (Cohen). Results: Concordance was highest in recognising deep muscle invasion {95.24% (Pathologist 1) and 100% (Pathologist 2)}, good for recognising the pattern {86.96% (Pathologist 1 & 2)} and grading the lesions {80.95% (Pathologist 1) and 68.42 (Pathologist 2)}, satisfactory for appreciation of lamina propria invasion {78.26% (Pathologist 1) and 69.57% (Pathologist 2)} and histopathological diagnosis {73.91% (Pathologist 1) and 56.52% (Pathologist 2)} and not satisfactory for identifying specific variants {50% (Pathologist 1) and 66.67% (Pathologist 2)}. Kappa value suggested almost perfect agreement for recognising deep muscle invasion (0.86), substantial agreement for both the pattern recognition (0.65) and grading (0.67), moderate agreement for lamina propria invasion (0.48), fair agreement for histopathological diagnosis (0.34)) and only slight agreement for recognising the specific variants (0.09). Conclusion: The interpretation of bladder neoplasms has satisfactory reproducibility on microphotographs. The evaluation of representative microphotographic images is a prudent and pragmatic exercise. The pathologists must train themselves to interpret the microphotographs images. The study emphasises the importance of intra-disciplinary consultation. The concept can be extrapolated and employed to solve perplexing cases my means of effective communication technology.

Keywords

• carcinoma
• lamina propria
• muscle
• pathology