PRINCIPLES AND TECHNIQUES OF

BIOPSYDr. Reham Lotfy Aggour

Lecturer of oral Medicine, Periodontology, Oral

diagnosis and Radiology

IT IS IMPORTANT TO DEVELOP A SYSTEMATIC APPROACH IN EVALUATING A PATIENT WITH A LESION IN THE ORAL

AND MAXILLOFACIAL REGION.•A detailed health history•A history of the specific lesion•A clinical examination•A radiographic examination•Laboratory investigations•Surgical specimens for histopathologic evaluation

BIOPSIES ARE AN IMPORTANT DIAGNOSTIC

TOOL FOR THE DIAGNOSIS OF LESIONS RANGING

FROM SIMPLE PERIAPICAL LESIONS TO

MALIGNANCIES.Biopsy is strongly recommended for the evaluation of most lesions that persist for 2 weeks or longer after the potential irritants are removed

What is a Biopsy?

Biopsy is the removal of tissue for the

purpose of diagnostic histopathologic examination.

Biobsy

Indications Contraindications

Equipment

Blade handle with a no. 15 blade Fine tissue forceps with teeth Local anesthetic solution and syringe Retractor appropriate for the site Suture for traction (if needed) Needle holder Suture for closure (if indicated) Fine-tipped scissors Laser or electrocautery device for fulguration (if

indicated) Specimen bottle containing formalin and biopsy

data sheet Gauze sponges 

Techniques There is often more than one

method of undertaking the surgery successfully. Whatever the method used, however, the aim is to:

1. Provide a suitably representative sample for the pathologist to interpret.

2. Minimizing perioperative discomfort for the patient.

General principles Local anesthetic: regional blocks or field blocks,

which are accomplished by means of nerve block or infiltration peripheral to the lesion.

An assistant may need to stabilize the area by using an instrument or his or her fingers.

Suction devices should be used with caution or completely avoided during excisional biopsy to prevent inadvertent loss of the specimen.

Elliptical wounds can be closed easily; however, depending on the location of the biopsy site and the size of the wound, mucosal undermining may help in producing a tension-free closure.

General principles (for intrabony lesions)

0

Flaps should be full thickness Mucperiosteal flaps should be designed to allow

adequate access for incisional/excisional biopsy. Incisions should be over sound bone Cortical perforation must be considered when

designing flaps Major neurovascular structures should be

avoided Osseous windows should be submitted with the

specimen Osseous preformations can be enlarged to gain

access

The lip is being held by a clinician and an assistant.

The tongue is being stabilized for biopsy.

wedge-shaped specimen with a length-to-width ratio of 3:1.

Fine-Needle Aspiration Biopsy

Fine needle aspiration cytology is a procedure whereby the pathologist uses a special needle and

syringe to enter the tissue and collect cells for histological examination. Commonly used in 

salivary gland tumors.

Any radiolucent lesion should have an aspiration biopsy performed prior to surgical exploration.

Information from the aspiration will provide valuable information about the lesion.

Solid, Fluid Filled,Vascular,Without Contents

Fine-Needle Aspiration Biopsy Advantages & Disadvantages

Avoiding unnecessary damage to vital structures.

Low risk of infection. Patient comfort. Disadvantages of FNAB: False-negative rates. Insufficient room in the oral cavity to

properly perform the movements necessary to aspirate material.

Excisional biopsy

Excisional biopsy The size of the lesion. The location of the lesion. The nature of its attachment to the

underlying tissue. The accessibility of the lesion. The regional anatomy

Small, pedunculated, exophytic masses in accessible areas are

excellent candidates for excisional biopsy.

Laser excision with biopsy for tongue growth.

Incisional biopsy

Incisional biopsies only

require removal of a

section of tissue

Incisional Biopsy Indications:

Size limitations Hazardous location of the lesion

Great suspicion of malignancy

Technique:

Representative areas are biopsied in a wedge fashion.

Margins should extend into normal tissue on the deep surface.

Necrotic tissue should be avoided.

A narrow deep specimen is better than a broad shallow one.

Soft tissue overlying the lesion should be reapproximated following thorough irrigation of the operative site.

Incisional biopsyThe biopsy site should

be carefully considered..

For ulcerated oral lesion. Selecting

only the center of an ulcer results in an

inadequate specimen devoid of

mucosa and with nonspecific

vasculitis at the base. In this case,

the edge of the ulcer would be of more

value in establishing a diagnosis.

For dark staining lesions→ Biopsy should be focused on the area of greatest staining.

Toludine blueIncisional biopsy can lead to a diagnosis of mild or moderate dysplasia despite the presence

of invasive cancer within millimeters of the biopsy site.

Therefore, a diagnostic adjunct may be used to guide the

clinician to the biopsy site that is most likely to be associated

with carcinoma in situ or invasive cancer.

Toluidine blue : a dye that predictably stains affected mucosa and not unaffected areas.

Binds to DNA A few drops of toluidine blue are applied to

the lesion and surrounding mucosa. Patients then rinse their mouths several times with a mild acetic acid solution.

When properly applied, toluidine blue staining is a highly sensitive and specific test for carcinoma in situ and invasive oral cancer.

Chemiluminescent light based systems

Under illumination, normal epithelium absorbs the light, appearing light blue, while abnormal tissue reflects the light and appears white, with sharper, more distinct margins.

Exfoliative cytology

Scrape off surface of lesion to BM if possible.

Useful for : HSV, Candidiasis, pemphigus, some bacteria, cellular atypia.

Exfoliative cytology

Computer-Assisted Transepithelial Oral Brush Biopsy

The oral biopsy brush is firmly pressed against lesion and rotated until pinpoint bleeding is observed.

The brush is then rotated onto the enclosed glass slide, transferring the cellular material. This unique tissue specimen is then subjected to specialized, computer-assisted laboratory

analysis. 

Specimen Handling

During the biopsy procedure, the lesion is grasped with an Allis forceps or secured with a traction suture.

Intraosseous and Hard Tissue Biopsy

Intraosseous lesions are most often the result of

problems associated with the dentition.

Indications for Intraosseous Biopsy

Any intraosseous lesion that fails to respond to routine treatment of the dentition.

Any intraosseous lesion that appears unrelated to the dentition.

Specimen Handling

The specimen should be removed from the field and placed into a solution of 10% formalin.

The volume of formalin should be at least 20 times the volume of the specimen

Special tests may require that a second specimen be submitted in a different solution. e.g: immunofluorescent studies. Specimens for direct immunofluorescence testing must be submitted in Michel solution.

Biopsy Data Sheet

When To Refer For Biopsy

When the health of the patient requires special management that the dentist feel unprepared to handle

The size and surgical difficulty is beyond the level of skill that the dentist feels he/she possesses

If the dentist is concerned about the possibility of malignancy