Sunday, October 12, 2008

Week 16 SIP

Hi



I have been attached to cytology for 3 weeks.



What is cytology?

Cytology is the study of cells obtain from bodily fluids.



The cytology department receives any fluid from the body such as CSF, aspirates, FNA, smears from urinary tract, reproductive system and so on. They split all the specimens into 2 categories, gynaecological and non-gynaecological. The gynae category means Pap smears (female reproductive tract from vaginal to cervical smears). Non-gynae is everything else.



Pap stands for Papanicolaou stain. It screens to detect premalignant and malignant tissues, mainly from the cervix.



How to take a Pap smear?

I "tooth-brush" like device is used to scrap cells from the opening of the cervix. The medical officer will rotate 360 degrees to gather cells from as large area as possible (to prevent false negative because some areas may not be scrapped). Then they will be smeared onto a slide and stained using the Pap staining method.



Instead of the usual H&E staining, gynae staining is slightly different. They have modified Eosin Azure instead of the normal Eosin, orange G stain and harris haematoxylin. Orange G stains for keratin, and the eosin is special because gynae cells cannot be stained by normal eosin. (I don't know why.)



The test aims to detect cells which are potentially pre-cancerous. The newest classification of degree of malignancy of gynae cells is called Bethesda system.
1. Atypical glandular cells (AGC)
2. Atypical squamous cells of undetermined significance (ASCUS)
3. Low grade squamous intraepithelial lesion (LSIL)
4. High grade squamous intraepithelial lesion (HSIL)
5. Squamous cell carcinoma




It is recommended that females who have had sex undergo regular Pap smear testing, once a year to once in 5 years. If the results are abnormal, they need to do a confirmatory test, about 6months later again (the same test). Other confirmatory test include colposcopy and HPV DNA testing. I am unsure how these are performed.






http://www.medskul.com/gallery/data/519/Faces_of_high_grade_squamous_intraepithelial_lesion_HGSIL_or_HSIL_.jpg

The above picture shows HSIL.


The main things to look out for to confirm malignancy is to observe the nucleus.


They MUST have these characteristics:
1. Enlargement of nucleus
2. Increase in chromatin density
3. Chromatin appears granular or clumped
4. Loss of reticular characteristics of benign cells


They MAY have these characteristics:
1. Hyperchromasia of nucleus (hyper-extreme, chroma-colour)
2. Polychromasia of nucleus (poly-multiple)
3. Changes of the shape of nucleus
4. Macronucleoli
5. Abnomal mitosis
6. Multiple nucleus per cell
(7. onwards are cytoplasm)
7. Unusual staining of cytoplasm
8. Formation of syncytical sheets with faded outline (I have no idea what it means)
9. Weird shape of cell


Thank you
Ernest
TG01
0606330i

14 comments:

tg01 group 2 said...

Hi,

Omg! did you actually saw how the medical officer perform e swabing of the cervix of the female? anyway is there another method on doing it? if i am not wrong my lab has another method in doing pap smear. my senior told me that new method is more accurate...

Ivan
TG01

tg01 group 2 said...

Hi ivan

Yes correct. There are new methods to obtain gynae cells. What I have mentioned is the conventional method.

The new methods are Thinprep and Sure-path (brand names). These are called liquid-based monolayer cytology.

The main difference is that the sample is in a liquid.
Then spread onto the slide but it is a monolayer of cells.

Advantages:
1. better for HPV low or high risk testing.
2.less unsatisfactory slides
3. better specificity and sensitivity

Thank you
Ernest

tg01 group 2 said...

To Ivan

PS: I did not see them perform cervical scrapings.

Thank you
Ernest

MadTechs said...

hi ernest...

you mentioned about "colposcopy". i understand you said you don't know how it's performed. but what is the purpose of the test? what can it do?

and, "weird shape of the cell".. what do you mean by "weird"? haha. as in, how exactly would it be like?

thanks C:

nur azeimah
0607060A
tg 02

group1 said...

hi,

you mention "It is recommended that females who have had sex undergo regular Pap smear testing, once a year to once in 5 years", but why? do you mean that it will have a higher possibility of getting "cancer" when people have sex?

just curious =P

Thanks,
Yumei
Tg01

hellomedtech said...

Hi..

u mentioned the Bethesda system..

i assume the first one (AGC)to be the least malignant and the last one (squamous cell carcinoma) to be the most malignant...am i right?

thanks =)

Nur Farhana
0604834B

THE CODEC 5 said...

Hi Ernest,

What is the difference between modified Eosin Azure and the normal Eosin? Is the components used to make them differen? Are there reasons why modified Eosin Azure is used instead of the normal Eosin?

Thanks.

Lyn
TG02

MadTechs said...

hey ernest,

how do you classify the gynae cells if it is Atypical glandular cells (AGC), Atypical squamous cells of undetermined significance (ASCUS), Low grade squamous intraepithelial lesion (LSIL), High grade squamous intraepithelial lesion (HSIL), Squamous cell carcinoma. is it based on the physical examination?

Liyanah Zaffre
0607718D
TG02

tg01 group 2 said...

Hi Ernest

Just some quick questions for you:

1)What is the key principle of colposcopy and HPV DNA testing? What does HPV stand for?

2)What are some of the health consequences if women do not go for Pap smear test?

Thankz!

Han Yang
TG01

tg01 group 2 said...

Hi azeimah

Colposcopy is the medical diagnosis of the lower female reproductive tract. The purpose is to find malignant or premalignant lesions.

Weird shape may refer to any irregularities of the cytoplasm.


Hi Yumei

Even if you stick to one to two sexual partners in your whole life, there is still an increased risk of getting a HPV infection, which will may lead to warts or cevical cancer.

Though not medically proven, there are 12 HPV types which are believed to cause cancer (or high risk types). They include type 16, 18, 31, 33, 35, 39, 45, 51 etc.


Thank you
Ernest

tg01 group 2 said...

Hi farhana

It is somewhat in this order because there is no clear cut line between different degrees of malignancy.

Hi lyn

EA consist of 3 dyes, EA-36, EA-50, EA-65. They are light green SF yellowish and eosin Y. Eosin Y stains the superficial epithelial squamous cells, nucleoli, cilia, and red blood cells. Light Green SF yellowish stains the cytoplasm of all other cells.

Thank you
Ernest

tg01 group 2 said...

Hi liyanah

It is based on microscopic examination. Mainly how much dysplasia has occured. However, HSIL does not mean that cancer is present. In fact, only 2% of cases are invasive if HSIL is detected.

One way to classify them is to look at where the dysplasia has occured. If it is within 1/3 of epithelium (basal), it is CIN 1. If it is less than 2/3, it is moderate dysplasia CIN 2. More than 2/3 is servere dysplasia, CIN3. In other words, the cells cannot mature to superficial cells.


Hi hanyang

Colposcopy is the medical diagnosis of the lower female reproductive tract. The purpose is to find malignant or premalignant lesions.

HPV stands for human papilloma virus. HPV DNA testing is to detect "low" and "high-risk" HPV genotypes. Example: type 31, 33, 45, 51, 16, 18 etc.

If women do not undergo regular PAP smear once every three years, dysplasia of the cervix cannot be detected. CIN 3 or HSIL cannot be detected.

Thank you
Ernest

tg01 group 2 said...

Hi,
Wat does hyper-extreme and chroma-colour means?

Ivan Ng
0605070B
TG01

tg01 group 2 said...

Hi ivan

I was referring to the definition.
Hyper means extreme
Chroma means colour
When you put these two words together, hyperchromasia, it means the stain is very intense.

Thank you
Ernest