L1: Importance of Surgical Pathology In Medical Practice

Question 1

What is the definition of pathology?

Answer 1

Is the science which deals with the study of diseases.

Question 2

What does the study of pathology include?

Answer 2

ENCF PPPP

1) Etiology.
2) Nature of the disease.
3) Pathogenesis.
4) Pathological examination of lesions.
5) Prognosis.
6) Complications.
7) Fate.
8) Pathological investigations.

Question 3

What is etiology?

Answer 3

This means the cause of the disease.

Question 4

What does etiology include?

Answer 4

• Predisposing factors

- Exciting factors

Question 5

Predisposing factors

Answer 5

-Factors that help the development of the disease.

• This occurs in one of two ways:
  1) Decreased body defense (favors infection).
  2) Increased susceptibility (suggested to be hereditary) as Bronchial asthma.

Question 6

Exciting factors

Answer 6

-Is the direct cause of the disease (i.e. cause lesion).

-It includes:
1) Defective fetal development in the uterus:
 Congenital.
 Hereditary (genetic). “Like Trisomy 21”

2) Acquired factors (after birth):
 Exogenous (environmental) factors as microbes, nutritional deficiency (protein, vitamins, etc.)
 Endogenous (internal factors) as endocrine disturbance, hypertension, peptic ulcer.

Question 7

What can the nature of the disease be?

Answer 7

-Congenital & Hereditary diseases.

-Acquired diseases:
 Inflammation.
 Degeneration. "Diseased but not dead"
 Circulatory disturbance. "Disturbance in CVS"
 Tumors.

Question 8

What is pathogenesis?

Answer 8

The mechanisms by which the causative agent produces the pathological changes in the tissues (i.e. mechanism of formation of the lesion.).

Question 9

Pathological examination of the lesions

Answer 9

Structural changes in the diseased tissues include:

 Gross picture (macroscopic picture): A naked eye description of the pathological changes.

 Microscopic picture (histological): These are the changes in the tissues of organs detected on microscopic examination by Light microscope, Electron microscope, and Immunohistological techniques

Question 10

What is an example of an immunohistological technique?

Answer 10

as immunofluorescence technique by the use of antibodies to various constituents of human cells and their products.

Question 11

What is the prognosis?

Answer 11

Is the forecast of the course & termination of a disease.

Question 12

What are “complications”?

Answer 12

• Are additional pathological changes which may occur during or after the termination of the usual course of the disease.
• They affect or modify the prognosis of the disease.

Question 13

What is the definition of “fate”?

Answer 13

It includes prognosis & complications of the disease.

Question 14

What do the pathological investigations include?

Answer 14

• Biopsy: This is the study of a specimen from the lesion during life.
• Autopsy: This is a post-mortem examination of the cadaver.

Question 15

What is the difference between congenital and hereditary diseases?

Answer 15

• Congenital disease: normally fertilized ovum is affected in the uterus by microbes, drugs, X-rays, etc.
• Hereditary (genetic disease): inherited from parents.

Question 16

What are lesions?

Answer 16

The structural changes occurring in the tissue as the result of the disease are called lesions.

Question 17

How are the material obtained for pathological investigation preserved?

Answer 17

The materials obtained are put immediately in a fixative fluid to prevent autolysis, mainly 10% formalin.

Question 18

What does surgical pathology involve?

Answer 18

Surgical pathology involves gross and microscopic examination of surgical specimens, as well as biopsies submitted by clinicians.

Question 19

What does the practice of surgical pathology allow us for?

Answer 19

definitive diagnosis of disease in removed tissue.

Question 20

How is surgical pathology performed?

Answer 20

This is usually performed by a combination of:
 Gross (Macroscopic) examination of the tissue.
 Histopathologic (Microscopic) examination.
 Molecular studies (immunohistochemistry).

Question 21

What are the types of spicemens?

Answer 21

• Excision biopsy
• Incision biopsy
• True-cut Biopsy
• Fine Needle Biopsy
• Aspiration of body fluids

Question 22

Excision Biopsy

Answer 22

Therapeutic surgical resection (TSR) of the entire lesion

Question 23

Incision biopsy

Answer 23

Surgical resection of part of the lesion for diagnosis.

Question 24

TRUE-CUT BIOPSY

Answer 24

The core of tissue is obtained by the use of large-bore needles, sometimes under the guidance of radiological techniques.

Question 25

FINE NEEDLE ASPIRATION

Answer 25

Fluid aspiration from the lesion tissue by a fine needle for cytologic smear preparation and examination of aspirated cells.

Question 26

Aspiration of body fluids

Answer 26

For cytologic smear preparation & examination (as urine, ascites…)

Question 27

Fixation

Answer 27

• Immediate specimen fixation is mandatory.

- The widely used fixative is 10% formaldehyde (Formalin) buffered to a neutral ph.

Question 28

What is the importance of fixation?

Answer 28

1) Fixation will preserve the morphology.
2) Prevent decomposition and autolysis.
3) Minimize microbial/fungal growth.
4) Minimize the loss of molecular components.

Question 29

Gross examination

Answer 29

LG COLR

1) Recognition of the anatomic landmarks for proper anatomic orientation and measuring specimen.
2) Localization of the lesion.
3) Opening and examination of the whole Specimen.
4) Cutting proper Sections needed for diagnosis (sampling).
5) Labeling sections.
6) Gross description which represents a permanent record of the specimen’s macroscopic features and enables the pathologist to correlate each slide to a precise location on the specimen.

Question 30

Microscopic examinations

Answer 30

• All samples cut grossly from the specimen should be processed and sectioned on glass slides.
• Sections should be stained by Hematoxylin and Eosin (H&E) for microscopic examination.
• Other special stains could be used.

Question 31

Immunohistochemistry

Answer 31

• Specific monoclonal antibodies help to identify cell products or surface markers
• Determination of the origin of the cell population.
• Detection of prognostic and therapeutic markers

Question 32

Intraoperative Consultation

Answer 32

-Rapid microscopic examination of fresh tissue is done for intraoperative consultation which is needed for important decisions during operation.

Question 33

What are the methods of intraoperative consultation?

Answer 33

Methods:
 Preparation of histologic slides using the frozen section technique.
 Preparation of cytologic slides.