Related Experiment Videos
Millipore filter cell block preparation: an alternative to cell block in nongynecologic specimens of limited
1Department of Pathology and Laboratory Medicine, University of Pennsylvania Medical Center, Philadelphia 19104, USA. zubair_baloch@path1a.med.upenn.edu
Abstract:
The use of membrane filters to concentrate cytology specimens was first described by Seal (Cancer 1956; 9:866-868). We report on a technique in which a portion of Papanicolaou-stained Millipore filter (Millipore Corp, Bedford, MA) preparation can be converted into a paraffin block for hematoxylin-eosin (H&E) preparations and immunocytochemical analysis (ICC). Seven cases with moderate cellularity and no cell block preparation were retrieved from our cytopathology files. The specimens included: 4 pleural effusions with metastatic adenocarcinoma, and 3 FNA specimens (1 metastatic melanoma, 1 metastatic adenocarcinoma, and 1 thyroid/papillary carcinoma). The filter was removed from the slide, cut in half, and subjected to paraffin embedding in the usual fashion (postfixed in 10% neutral-buffered formalin). Four-micron-thick sections were cut onto Probe-On (Fisher Scientific, Pittsburgh, Pa) slides. ICC was performed using the avidin-biotin-peroxidase complex technique and capillary gap technology. Antibodies included CAM5.2, AE1/AE3, CEA, CD15, LCA, PanCK, S100, HMB45, and thyroglobulin. All cases showed excellent preservation of cellular morphology on H&E. ICC performed on Millipore filter cell block preparations showed specific antibody staining patterns with preservation of cellular details. All antibodies showed their specific staining patterns with clean background and lack of nonspecific staining. This technique has the following advantages: 1) offers an alternative to cell blocks in moderately cellular specimens; 2) clean background; 3) preservation of cytology specimens for future studies.
Insights
This study presents a novel method to create paraffin blocks from Millipore filters for cytology specimens. This technique enhances cell block preparation for hematoxylin-eosin staining and immunocytochemical analysis.
Area of Science:
- Cytopathology
- Histopathology
- Oncology
Background:
- Membrane filters are used to concentrate cytology specimens.
- Traditional cell block preparation can be challenging for moderately cellular samples.
Purpose of the Study:
- To describe a technique for converting Papanicolaou-stained Millipore filter preparations into paraffin blocks.
- To evaluate the utility of these paraffin blocks for hematoxylin-eosin (H&E) staining and immunocytochemical analysis (ICC).
Main Methods:
- A portion of Papanicolaou-stained Millipore filters from seven cytology cases was processed for paraffin embedding.
- Sections were cut and stained with H&E.
- ICC was performed using specific antibodies and capillary gap technology.
Main Results:
- The technique yielded excellent preservation of cellular morphology on H&E staining.
- ICC on Millipore filter cell block preparations showed specific antibody staining with clean backgrounds.
- All tested antibodies demonstrated their expected staining patterns without nonspecific staining.
Conclusions:
- This method offers a viable alternative to traditional cell blocks for moderately cellular specimens.
- It provides a clean background for ICC and preserves cytology specimens for future studies.