Draft, letter to the Editor, Arch Pathol Lab Med

Dear Editor, 

I’ve been dealing with thoracic pathology for 9 years. Mostly in a reference health center specialized in diagnosis and therapy of thoracic disease, either neoplastic or not. In that period I personally signed out thousands of reports and performed thousands of intraoperative consultations. At the beggining therule was to perform frozen sections on any sample provided by the surgeon. However, when I had to go at different distant places where no cryostat was available I started to use Touch Preparation Cytology alone. Perhaps that was the most important moment in my daily practice. The decision of rely diagnosis on a simple, cheap, quick and confident method. After years I eventually abandoned frozen sections and in every case just made TPC. Now Ihave more than 6 years of experience with intraoperative TPC in virtually any organ of the body. Now I could confident say that TPC is the best method for quick intraoperative diagnosis. During these years I perfectioned a procedure that makes me able to render a diagnosis in about 5 minutes, including the grossing of the sample and microscopy analysis.

The technic is as follows:

1. Detailed gross analysis. Mainly to confirm and define the presence of pathology. A gross diagnostic impression must be obtained in concordance with the findings in CT scans and other available imagenologic studies and theopinion of the physician dealing with the case. The area were TPC and scrapping must be performed is carefully selected. Two minutes could be necessary but seldom more than 5 mins (except for large resections)
2. 1 or 2 slides are obtained and fixed in 95° alcohol for 30 secs.
3.Then rinsed in tap water, 10-15 secs.
4. The moisted slides are then exposed to a solution of 1% Methylen Blue for 15 secs.
5.Then wash in water till the excess of colorant dissapear, about 5 secs is enough.
6. Put coverslips.

TPC are ready for examination in less than a minute and a half. At a glance diagnosis could be rendered in less than a minute if you are an experienced pathologist. And that’s all. Minimum cost, light efford and, if properly performed, superb cytologic quality.

Methylene Blue stain shares many of the staining properties of the more traditional Giemsa stain, as both employ the same basic dye.
The nuclear details are sharply delineated: chromatin both disperse or clumped, nuclear envelope profile, nucleoli, mitotic figures.
Poor cytoplasmic stainning is perhaps the negative aspect that could object the orthodox microscopists. Although most cells show a lightly blue hue easilyappreciated, thus the amount of cytoplasm, the relative position of the nuclei and nucleus/cytoplasm ratio could be analyzed.

Another objection that could be emphasized is that TPCs mounted in water are not permanent. The stain vanishes with time an cells become dessecated. Two options are available for eliminate the problem. First, the dessecated slides could be rehydrated and restained with the same procedure described above. The cells were fixed in alcohol thus when adhered to the glass and fixed they will remain unchanged for many years if properly stored (without light, in a fresh and dry container). Alternatively an HE stain could be performed on the former MB stained TPC. I had restained slides after years of storing and results are the same observed previously. Second, after the intraoperative consultation finished, the MB stained slide could be dehydrated,cleared and mounted with permanent medium, but anyway, as happens with Giemsa stain, the dye will vanish in time, so you could restain with HE prior topermanent mount them.

This method is specially suitable for places were the pathologists are not provided with equipment. A very common situation in undeveloped countries. Also when a intraoperative consultation is requested but no pathology lab is present in the health center.

A quick diagnosis and/or quality sample evaluation could be made at the side of the ultrasound guided biopsy or needle aspiration site, or immediately afteran endoscopic biopsy is obtained. Small samples are specially suitable for TPCanalysis. All you need is some slides, a box of cover slips, few drops of Methylene Blue solution, 95° alcohol and water. These items could be boxed in a little plastic bag or container, you could even carry them in your pocket. Remember that both alcohol and water would be found in any surgical room.

I had developed and tested this procedure just because of the context in which I am working in. Anyway, I consider that any worlwide pathologist could found it useful sometime.

Besides, a fast stained TPC could help to an accurate diagnosis as an aid to the most sofisticated technic or perfect frozen section.





Juan J. Barcia MD

Aggregate Professor of Surgical Pathology.Medicine Faculty.Universidad de la Republica.Consulting Pathologist in Thoracic Pathology.ASSE. MSP.Montevideo, Uruguay.