Squash preparation: A reliable diagnostic tool in the intraoperative diagnosis of central nervous system tumors

Abstract

Background:Intraoperative cytology is an important diagnostic modality improving on the accuracy of the frozen sections. It has shown to play an important role especially in the intraoperative diagnosis of central nervous system tumors.Aim:To study the diagnostic accuracy of squash preparation and frozen section (FS) in the intraoperative diagnosis of central nervous system (CNS) tumors.Materials and Methods:This prospective study of 114 patients with CNS tumors was conducted over a period of 18 months (September 2004 to February 2006). The cytological preparations were stained by the quick Papanicolaou method. The squash interpretation and FS diagnosis were later compared with the paraffin section diagnosis.Results:Of the 114 patients, cytological diagnosis was offered in 96 cases. Eighteen nonneoplastic or noncontributory cases were excluded. Using hematoxylin and eosin-stained histopathology sections as the gold standard, the diagnostic accuracy of cytology was 88.5% (85/96) and the accuracy on FS diagnosis was 90.6% (87/96). Among these cases, gliomas formed the largest category of tumors (55.2%). The cytological accuracy in this group was 84.9% (45/53) and the comparative FS figure was 86.8% (46/53). In cases where the smear and the FS diagnosis did not match, the latter opinion was offered.Conclusions:Squash preparation is a reliable, rapid and easy method and can be used as a complement to FS in the intraoperative diagnosis of CNS tumors.

Intraoperative Squash and Touch Preparation Cytology of Brain Lesions Stained with H+E and Diff-Quik™: A 20-Year Retrospective Analysis and Comparative Literature Review

“…4 a-d). Other studies in the literature have also described the difficulty of distinguishing metastatic carcinoma from GBM [8,15,18] . Conversely, GBM is also occasionally misidentified as metastatic carcinoma [6,12,17,18] .…”

“…Glial tumors such as oligodendroglioma, oligoastrocytoma, and subependymoma were especially difficult to diagnose solely by SP/TP cytology. Oligodendroglial tumors contain monotonous round cells with mildly pleomorphic tumor nuclei [18,24] , which could be difficult to distinguish from glial cells. Other investigators similarly imprecisely categorized oligodendrogliomas and ependymomas as a broader category of glioma [23] .…”

“…persing firmer lesions pose diagnostic challenges [15,18,20,24,27] . Touch/imprint preparation (TP), on the other hand, has also been utilized in intraoperative brain assessments [3,5,7,11,15,24] , though far less frequently.…”

Rapid immunocytochemistry based on alternating current electric field using squash smear preparation of central nervous system tumors

“…[8] [9] R-ICC by microwave-based method for intraoperative peritoneal washing cytology of pancreatic or biliary carcinoma was previously reported [10]. Recently, the usefulness of R-ICC of cytokeratin in touch print of sentinel lymph nodes for evaluating metastasis of breast cancer has been reported [11] [12].…”

Press Imprint Smear: A Rapid, Simple, and Cheap Method for the Diagnosis of Cutaneous Leishmaniasis Caused by Leishmania (Viannia) braziliensis

“…On a firm surface, the tissue fragment between both glass slides was squeezed (squashed). 6,7 Pressure on the middle of the slides was made, and therefore, the juice and tissue cells were spread on both slides' surfaces that were in contact with the sample (Figure 2A and B). To avoid smears being too thick, slight movements were made (Supplemental Videos 1 and 2).…”