Familiar trespassers in histopathology: An obstacle in diagnosis? A single-blind study

Background: Histopathologists encounter strange structures in tissue sections that appear unrelated to tissues, and these artifacts may be misinterpreted and misdiagnosed as pathological lesions. These substances may either be present within the tissues or can get implanted into tissue during biopsy procedure or laboratory handling or processing. Aims: The aim of this study is to observe the microscopic appearance of different abnormal structures like commonly implanted food particles or easily incorporated substances during tissue processing with their probable histological misdiagnosis. Materials and Methods: Certain food particles, suture materials, wood pieces, insects, and filter paper were intentionally introduced in the tissue specimens of uterus and lung. Following routine processing and hematoxylin and eosin staining, the slides were subjected to single-blind study and viewed under light and polarizing microscope. Results: The vivid appearances of these structures lead to histological misdiagnosis. Conclusion: Knowledge and familiarity of these commonly encountered extraneous substances will help to prevent misinterpretation.