Imprint Cytology: A Cost-Effective Alternative Test for Frozen Section in Intraoperative Consultations for Cancer Surgery

Abstract

Introduction: Frozen Section (FS) helps in the typing of cancer – benign or malignant, tumor subtyping, assessment of margin status and lymph node involvement by the tumor preoperatively. Imprint smear (IS) study in place of Frozen section for intraoperative consultations can be conducted in those Institutes where facility of cryostat is unavailable. This study aims to determine the reliability of Imprint smear study done in intraoperative specimens as an alternative to frozen section by correlating with the Histopathological diagnosis. This is a Materials And Methods: retrospective study conducted at the Government Royapettah Hospital, Chennai over a one-year period from January 2020 till December 2020. The results of Imprint smear study in intraoperative specimens were compared with the histopathological results. We studied 96 per operative Results: specimens that included 48 lymph nodes, 23 ovary, 17 breast, 4 soft tissue, 2 thyroid, 1 bone and 1 cervix specimens. The Imprint study results, when compared with Histopathological diagnosis, showed an overall correlation of results for 83 specimens with a sensitivity of 98.60%, specicity of 52.0%, positive predictive value of 67.26%, negative predictive value of 97.38%, accuracy of 75.30% and p-value of 0.00 suggesting statistically signicant association. Based on the above results, wit Conclusion: h higher value of sensitivity and negative predictive value, the cases reported as negative for malignancy in imprint smear can be nalized as negative thereby preventing radical resection for clinically doubtful malignant cases diagnosed as benign lesions. Imprint smear also helps in providing a timely per operative diagnosis of malignancy guiding the operating surgeons for completion of radical surgery and thereby reducing a re-exploration surgery after diagnosing malignancy later in Histological sections. We conclude that an attempt to do imprint smear study should be done at every institution where cryostat facility is not available