Digital slide imaging in cervicovaginal cytology: a pilot study.

CONTEXT: Digital whole slide imaging is the anticipated future of anatomic pathology, where sign-out of glass slides will be replaced by scanned images. Whole slide imaging has been successfully used in surgical pathology, but its usefulness and clinical application have been limited in cytology for several reasons, including lack of availability of z-axis depth focusing and large file size. Recently, several systems have become available in the United States for whole slide imaging with z-axis technology. OBJECTIVE: To determine the accuracy and efficiency of whole slide imaging, as compared with traditional glass slides, for use in cervicovaginal diagnostic cytology. DESIGN: Eleven cervicovaginal cytology cases (ThinPrep and SurePath) scanned at ×20, ×40, and ×40 z-stack magnifications using the BioImagene iScan Coreo Au 3.0 scanner were evaluated by 4 cytotechnologists and 3 pathologists in a blinded study. Different magnification scans were recorded as separate cases and presented in a randomized sequence. Corresponding glass slides were also reviewed. For each case, the diagnoses and total time to reach each diagnosis were recorded. RESULTS: Diagnostic accuracy was higher and average time per case was lower with glass slides as compared with all digital images. Among the digital images, the ×40 or ×40 z-stack had the highest diagnostic accuracy and lowest interpretation time. CONCLUSIONS: Whole slide imaging is a viable option for the purposes of teaching and consultations, and as a means of archiving cases. However, considering the large file size and total time to reach diagnosis on digital images, whole slide imaging is not yet ready for daily cervicovaginal diagnostic cytology screening use.

Identification of tissue of origin in body fluid specimens using a gene expression microarray assay.

BACKGROUND: Body fluid specimens may be the first and only pathologic specimen for clinical evaluation in metastatic cancer cases. The challenge of identifying the tissue of origin in metastatic cancer has led to the emergence of molecular-based assays, such as the microarray-based Pathwork Tissue of Origin gene expression test. The ability to use body fluid specimens in this test would be valuable in providing diagnoses to cancer patients without clearly identifiable primary sites. In the current study, the authors evaluated the Tissue of Origin Test for use with malignant effusion specimens. METHODS: A total of 27 metastasis-positive body fluid specimens from different body sites, including pleural, ascites, pericardial, and pelvic wash fluids, were obtained from patients with known diagnoses. Nine specimens from nonmalignant body fluids were included as controls. RNA was extracted from formalin-fixed, paraffin-embedded (FFPE) tissue and gene expression analysis was performed with the Tissue of Origin Test. RESULTS: Seventeen of 27 metastasis-positive samples were non-necrotic with ≥60% tumor and yielded sufficient RNA. Of these samples, 94.1% (16 of 17) were in agreement with the available diagnosis. Of the 9 negative control samples evaluated, 7 (77.8%) demonstrated microarray expression profiles most similar to lymphoma, which is consistent with the predominance of inflammatory cells in these specimens. CONCLUSIONS: The results of the current study demonstrated that FFPE cell blocks from cytologic body fluid specimens yield adequate diagnostic material for the Pathwork test and can be used in the workup of patients with unknown primary tumors.

Limiting the use of atypical/inconclusive as a category in nongynecologic cytology specimens.

CONTEXT: 'Atypical' has served as a descriptive term in cytology since the birth of the specialty by Dr Papanicolaou. This indeterminate diagnosis often results in repeat biopsies or additional tissue sampling and a needless delay in patient care if used inappropriately. Because of the definitional ambiguity of this term and the associated physician frustration, we have made a concerted effort at Methodist Hospital since 1995 to minimize the use of 'atypical' as a diagnostic category. OBJECTIVE: To evaluate whether the dissolution of the 'atypical' category has increased our cytologic-histologic discordance rate to more than the published reference range. DESIGN: From March 3, 2006, through December 31, 2008, all nongynecologic cases with 'atypical/indeterminate' listed as the general diagnostic category were identified and retrieved from our laboratory data files. We then assessed the cytologic-histologic correlation rate during the corresponding time frame. RESULTS: A total of 48 'atypical' cases (0.2%) from 19 347 nongynecologic specimens were identified. Of the 'atypical' cases, 52% (25 of 48) had intradepartmental consultation, 58% (28 of 48) had additional preparations examined, and 29% (14 of 48) documented limitations because of poor preservation. Our cytologic-histologic discrepancy rate for the period was 5.5% (214 of 3912 cases), with 89.3% (191 of 214 cases) resulting from sampling issues. On review of the small percentage of cytologic interpretative discrepancies, only one case was unhampered by less than 10% tumor cellularity or poor preservation. CONCLUSIONS: Not using 'atypical' as a diagnostic category, unless defined by Bethesda guidelines, has not affected our cytologic-histologic correlation rate.