Answers to Questions

QN 1: what type of tissues did you usually stain?

Siti

ANS: For our lab, we don’t usually know what we are staining as the specimens were already trimmed by the pathologists and some specimens are really very small, so it is very difficult to be identified. However, I have been to the trimming room for the first week, I will name some organs that are being trimmed and then sent for staining. The most common types of tissues are breast, colon, cysts, uterus, kidney and liver and the lymph nodes.

QN 2: if you have diagnosed a tissue which is malignant,will the staining solutions in the auto-stainer machine be contaminated and affect the subequent tissues(which may not be malignant)that are going to be stain?

Yong Herng

ANS: For our lab, we do not diagnose any slides, unless they are checking the quality of the slides. By right, the tissues are already fixed on the slides using hotplate, so the chances of it to contaminate the staining solutions is quite low. However, if the tissues are not fixed on the slides properly, some tissue parts might wash away and stay in the staining solution. This might result in the production of floaters in the subsequent slides which might lead to misdiagnosis. Thus, staining solutions should be filtered daily or change in alternate days.

QN 3: Do you have any microscopic pictures on how a normal and malignant tissue differs in morphology and staining? Thank you.

Li Yinliang Alex

ANS:

The picture on the left is an example of tumor cells of the liver where the cells become irregular in shape and there is an abnormal increase in the number of nucleus.


The picture on the left is an example of normal cells of the liver.

Reference:
1) IHC World, normal H&E staining,taken on 1st july 2009, from
http://www.ihcworld.com/imagegallery/displayimage.php?album=3&pos=16

2) Atlas of pathology, H&E staining of tumor liver, taken on 1st July 2009, from
http://www.pathologyatlas.ro/chronic-myeloid-leukemia-liver.php

QN 4: after examine the stain under microscope,do you store the specimens for a day or two or just simply throw it away?

Nyzah

ANS: Are you referring to the specimens that are trimmed or the slides that are stained? For the specimens that are trimmed, they are stored for about 2-3 months. For the slides that are stained, they are stored for about 10 years.

QN 5: What is photo-oxidation and how exactly does it affect the microscopic images of the slides?

Siti

ANS: Photo-oxidation is where Haematoxylin oxidized due to the presence of visible light and oxygen where it will produce a layer of oil-like substance floating at the top of the Haematoxylin solution. This oil-like substance is also known as scum. As it is floating on top of the solution, it will stick onto the slides when they are lifted up, hence, affecting the quality of the stains.

QN 6: Erm for the staining right, isnt Haemetoxylin being used to stain so what is the reason of using Lithium Carbonate? Is there other function of Lithium Carbonate?

Jennifer

ANS: Yup..Haematoxylin is being used to stain the nucleus blue but Lithium Carbonate is used to maintain the blueness or make it bluer. From what I have learnt so far, I don’t think that there is other function.