Grossing.pptx

Lecture slides about tissue grossing for university students

1. Mbarara University of Science & Technology 1

2. Mbarara University of Science & Technology 2 Specimen received and taken to the grossing room Left: specimen received with adequate formalin for size Right: s pecimen received with little formalin for size

3. Introduction Grossing is the macroscopic description of tissue. Gross description provides information that aides the pathologist in making a diagnosis during microscopic evaluation of the tissue. It includes cutting smaller pieces of tissue from the entire gross specimen submitted to the laboratory. Mbarara University of Science & Technology 3

4. Cont’ These pieces of tissue are likely to be more diagnostically significant in relation to the entire specimen, and are placed in tissue processing cassettes for processing. An accurate diagnosis from the tissue is dependent upon the correct identification during grossing Mbarara University of Science & Technology 4

5. Requirements for a grossing room Weighing scale Measuring cylinder Camera Pencil and pens for labeling cassettes Tissue cassettes Grossing ink Mbarara University of Science & Technology 5 Ruler with millimeter scale Magnifying lens 10% Neutral buffered formalin Waste bins, sharps container. Disinfectant (70% alcohol )

6. Requirements for a grossing room…… Sink with running tape water Fume extractor/ fume hood Surgical blades and scalpels Grossing knife, scissor and forceps Formalin absorbent padr Water proof apron Mask, Gloves Grossing board Mbarara University of Science & Technology 6

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10. Tissue blocks are placed into the cassette. Note they should not fill the cassette, and must permit room for processing fluid circulation. The orientation of the blocks is enhanced by a sponge securing the specimens in sequential position Mbarara University of Science & Technology 10

11. General Principles/Rules of grossing tissue. There should never be more than one container open at a time to ensure that each specimen is returned to its appropriate container so there is no chance of mix up. Qualified staff should do sampling of specimen. The grossing of the specimen can be done either before fixation or following it. It is ideal to gross larger specimen in a fresh state and smaller following fixation. Mbarara University of Science & Technology 11

12. General Principles/Rules of grossing tissue… The sample should be described in terms of the shape, size, color, texture and defining characteristics of the specimen. This means that small biopsies, for example endoscopic mucosal samples, may simply be afforded a simple descriptor in the form of the number of pieces and the size (SI units, usually mm) of the largest piece of tissue. E.g ‘three pieces of brown tissue, the largest 3 mm diameter’ Mbarara University of Science & Technology 12

13. General Principles/Rules of grossing tissue.… A properly completed surgical pathology requisition form containing the patient’s identification, age, sex, essential clinical data, nature of operation, surgical findings, tissue submitted and the site of biopsied specimen should accompany every specimen. If more than one specimen has to be placed in the same container, for the same patient, they must be clearly marked, which is most readily done by means of sutures; Mbarara University of Science & Technology 13

14. Cont’ Description of additional specimens received from the same patient must be mentioned . Non tissue materials such as bullets, implants, foreign bodies should be recorded as it may be essential for medico legal cases. Mbarara University of Science & Technology 14

15. General Principles of grossing tissue… Only labeled specimens should be accepted. The label should be firmly attached to the body of the container so that it cannot be separated. Specimen labels should not be attached to just the lid but the body of the container as well. Incorrect identification of any specimen results in the wrong diagnosis and incorrect treatment to potentially two patients. Mbarara University of Science & Technology 15

16. General Principles of grossing tissue… Measurements of the skin surface dimensions and depth should be documented. Any tissue that is small enough to slip through the cassette holes should be wrapped in processing tissue paper or a processing mesh bag. Tissue should only be inked if it conveys information such as orientation and margins in excisions, or which side to embed down. Mbarara University of Science & Technology 16

17. General Principles of grossing tissue… Unusual skin surface or pigmentation should be noted. Thickness of the specimen; A uniform thickness of the specimen is an obvious requirement for processing, but it is difficult to achieve under conditions of insufficient fixation or inadequate hardening of specimen. Mbarara University of Science & Technology 17

18. Cont’ The tissue thickens should ideally be 2 to 4 mm in thickness. Under no circumstances should any portion of the specimen be discarded before the case is signed out. Mbarara University of Science & Technology 18

19. Safety during Grossing All tissues must be considered potentially hazardous and universal precautions must be taken when grossing tissue. Formalin fumes are also known to be a health hazard. It is a severe eye and skin irritant and is toxic by ingestion and inhalation, these can be minimized by proper tissue handling and fixation of the specimen before grossing. Mbarara University of Science & Technology 19

20. Cont’ Adequate protective measures to protect from infection must be undertaken such as use of disposable gowns, gloves, facemasks and eye gear. Wash hands regularly to avoid spread of infection. Mbarara University of Science & Technology 20

21. Cont’ Grossing should be under a fume hood or safety cabinet designed to extract formalin vapors Contact with chemicals should be minimized and the protective gear should be disposed off in correct manner. The laboratory personnel should clean all instruments and working surface with a disinfectant. Mbarara University of Science & Technology 21

22. General Procedure for grossing. 1. Assemble the requirements and wear PPE. 2 .Correspond the identifiers on the specimen container with those on the request form. 3 .Make a general inspection of the specimen, with identification of all of its normal and abnormal components. 4 .Macroscopically describe the specimen by looking at and noting features like; colour , texture, dimensions, weight, shape and unique features like ulcerations, skin , muscle that may be attached to specimen Mbarara University of Science & Technology 22

23. General Procedure for grossing… 5 .Place the specimen on a grossing board and orient the tissue in its anatomical position . 6 .The identification markers for orientation such as sutures must be carefully considered. 7. Surgical margins should be identified correctly after orienting. Mbarara University of Science & Technology 23

24. Cont’ 8 .Photographs of the specimen are then taken, before its dissected. 9 .The pathologist must use sharp cutting instrument to avoid artifacts and cuts through the specimen to revel the inner part (cut surface ). 10 .The macroscopic description of the cut surface is then noted Mbarara University of Science & Technology 24

25. Cont’… 11 .If the cut surface contains a tumor, its deception like colour , texture , dimension are noted. 12 .Photographs of the cut surface are then taken. 13 .Orientation will determine the depth of invasion of the lesion and the margins of resection. Mbarara University of Science & Technology 25

26. Cont’ 14 .The specimen is then sampled to make representative portions of the entire gross specimen. 15 .The sampled tissue is then placed in a labeled tissue cassette. 16 .The sampled tissue should be of 2-4 mm . Mbarara University of Science & Technology 26

27. Cont’ 17 . The tissue cassettes are then covered and placed in a specimen 10%NBF ready for processing 18 . The working area and instruments are cleaned after grossing.. Mbarara University of Science & Technology 27

28. Note 1 .At no point should tissue dry during grossing 2 .Contamination of the specimen can occur anytime during the handling of the specimen, for example, floaters, cutting board metastasis which must be carefully eliminated, by washing the cutting tools and grossing board with running tape water before cutting another specimen . Mbarara University of Science & Technology 28

29. Cont’ 3 .Tissue samples dissected from the main specimen should be immediately placed in tissue cassettes with surface to be sectioned facing down wards, so that it is embedded correctly. Mbarara University of Science & Technology 29

30. These cassettes are over-loaded. If processing goes ahead the specimens will be distorted and it is likely that the processing will be incomplete These illegible cassette labels are totally unacceptable Mbarara University of Science & Technology 30

31. Specimen Orientation during Grossing *Right breast lumpectomy Received fresh *Suture identification (long lateral and short superior) and specimen orientation Mbarara University of Science & Technology 31

32. Specimen Painting/Inking Margins identified and painted *Anterior yellow *Superior blue *Posterior black *Inferior red Mbarara University of Science & Technology 32

33. The purpose of inking during grossing To determine the margins of the specimen. Indicate specific areas of interest to the pathologist To indicate the mode of embedding. Maintain the anatomic orientation of the specimen. Inks of different colors designating each of six specimen margins (superior, inferior ,medial, lateral, anterior and posterior) can ideally be used to do this. Mbarara University of Science & Technology 33

34. Note Inking cut surfaces of tissue one color will help in embedding to determine which surface should be embedded down, where inked surfaces will meet the blade first during the microtomy process. Inking is typically reserved for excisions. Inking margins on biopsies is not required since a second procedure is anticipated based on the diagnosis of the biopsy Mbarara University of Science & Technology 34

35. Formalin Fixation Mbarara University of Science & Technology 35

36. Specimen Slicing/bread loafing Specimen serially sectioned *Lesion identified *Margin evident Mbarara University of Science & Technology 36

37. THE END Thank you Mbarara University of Science & Technology 37

38. Reference World Journal of Dentistry, April-June2010;1(1):35-41 Handling and Grossing of Large Breast Specimens Anita Bane MB, BCh , FRCPath , PhD , Juravinski Hospital & Cancer Centre McMaster University UCI Histopathology laboratory Standard Operating Procedure, GROSSING/CUT UP 2017. Bancroft’s Theory and Practice of Histological Techniques, seventh edition 2012 38 Mbarara University of Science & Technology