Usefulness of imprint cytology for early diagnosis in vertebral lesions

Abstract

Background: Vertebral pathologies can be divided into degenerative, infective, or neoplastic. Infective and neoplastic lesions can progress rapidly and may lead to compression of the cord. Thus, rapid diagnosis for these lesions is important. Frozen section and fine-needle aspiration cytology techniques are less useful in hard bony tumors. Imprint cytology has been successfully used in the diagnosis of soft tissue tumors. The purpose of this study was to evaluate the role of imprint cytology in the early diagnosis of various spinal pathologies. Materials and Methods: Thirty-eight patients with suspected diagnosis of infection or tumor underwent transpedicular biopsy using Jamshidi needle. At least two imprint slides were made using core tissue obtained from biopsy. These slides were, thereafter, stained with the May-Grunwald–Giemsa method. The core biopsy sample was also sent for histopathological examination, after fixing it with 10% formalin. Paraffin-embedded blocks and slides were made for histopathology reporting, as per institution’s protocol. All imprint cytology slides were screened and reported by same pathologist. Results: The sensitivity of imprint cytology was 68.6%. Specificity, positive predictive value, negative predictive value, and overall accuracy of the imprint cytology were 100%, 100%, 21.4%, and 71%, respectively, when compared to histopathology. The mean duration of imprint cytology reporting was only 36 min while that for histopathological report was 15 days. Conclusion: Imprint cytology is a simple and rapid method for obtaining diagnosis in suspected vertebral lesions of infection or tumor. It is a reliable and cost-effective method in experienced hands. Although imprint cytology shows modest correlation in the ability to identify positive results, it forms a good diagnostic tool in confirming true negative cases with high diagnostic efficacy.