oral biopsy

Oral biopsy; why, when, and how?

Dr. Ahmed M. Adawy Professor Emeritus, Dep. Oral & Maxillofacial Surg.

Former Dean, Faculty of Dental MedicineAl-Azhar University

Definition:Biopsy is a Greek derived word, Bios = life and Opsis = visionBiopsy is the removal of the tissue from the living organism for the purpose of microscopic examination and diagnosis

Oral biopsy; why, when, and how?

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Oral biopsy

There are oral lesions whose diagnosis can be made relying on data collected during history taking and /or physical examinations, but there are others where histopathologic examinations are needed to confirm the presumed clinical diagnosis. Looking for a definitive diagnosis is the aim of biopsy

Oral biopsy, Why?The aim of biopsy is to : Define a lesion on the basis of its histopathological aspect To establish a prognosis in malignant and premalignant lesions Facilitate the prescription of specific treatment Contribute to the assessment of the efficacy of the treatment To determine whether an abnormality has been completely removed.• Act as a document with medical-legal value

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Oral Biopsy, Why?

Biopsy is indicated for diagnostic confirmation of suspected malignant lesions, precancerous lesions such as leukoplakias or erythoplakias and chronic ulcerations of unknown cause, and is recommended for apparently inflammatory lesions that do not improve within two weeks of removal of local irritants

Leukoplakia

Erythoplakia

Chronic ulcerations

Oral Biopsy, Why?

Other lesions that should also be biopsied include: Lesions that interfere with oral function, such as fibrous hyperplasias and osseous lumps Lesions of unclear etiology, particularly when associated with pain, paraesthesia or anaesthesia Radiolucent or radio-opaque osseous lesions Biopsy is also indicated for the histological confirmation of certain systemic disorders. Such as biopsy of minor salivary glands is for the diagnosis of Sjögren's syndrome

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When oral biopsy is not needed?

There is no need to biopsy normal structures There is no need to biopsy irritative or traumatic lesions that respond to the removal of a presumed local irritant There is no need to biopsy inflammatory or infections lesions that respond to specific local treatments, as pericoronitis, gingivitis or periodontal abscesses

1. When the general health condition of the patient is very poor2. When acute, virulent, pyogenic infection is present3. Pulsating lesions (those of vascular nature)4. Pigmented lesions (melanoma) should not biopsied as it may transform into malignant by cutting through it or may spread to distant organs

When oral biopsy is contraindicated?

5. Biopsy is not advised in the case of multiple neurofibromas, due to the risk of neurosarcomatous transformation, or in tumors of the major salivary glands. Such biopsies must be performed by specialized surgeons, in order to avoid damaging nearby anatomical structures and causing the spread of tumor cells, as this would adversely affect the prognosis (3)

When oral biopsy is contraindicated?

Feature of the lesion• Direct biopsy: when the lesion is located on the oral mucosa and can be easily accessed with a scalpel from the mucosal surface• Indirect biopsy: when the lesion is covered by an apparently normal oral mucosa

Types of biopsyAccording to the procedures applied, oral biopsy can be classified by:

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Area of surgical removal:• Incisional biopsy: consists of the removal of a representive sample of the lesion and normal adjacent tissue in order to make a definitive diagnosis before treatment• Excisional biopsy: is aimed at the complete surgical removal of the lesion for diagnostic and therapeutic purposes


Timing of the biopsy:• Pre-operative• Intra-operative• Post-operative, when aimed at checking the efficiency of a treatment


Before the procedure is undertaken, the characteristics of the lesion (size, shape, colour, texture, consistency, time of evolution, associated signs and symptoms, regional nodes) should be described in the patient’s clinical records together with a presumed diagnosis and possible differential diagnosis. The patient should receive information on the reasons why it is performed, avoiding terms that may cause anxiety. Informed consent is required

General principles of oral biopsy

Technique simple, only a portion of the lesion is removedSelects a representive portion of the lesion, especially select areas most likely to demonstrate most advanced disease

Incisional Biopsy

Incisional Biopsy Biopsy of a wedge of representative tissue Several regions may be sampled Avoid necrotic tissue Areas of tissue transition can be useful, such as the margin of the lesion Wedge should be deep enough to sample the full depth of the lesion and its transition to normal tissue

Incisional Biopsy Incisional Biopsy; Importance of obtaining a deep tissue specimen

Excisional Biopsy

Removes the entire lesion at the time of tissue sampling A margin of normal tissue is generally included Offers the advantage of definitive treatment at the time of diagnosis

Excisional BiopsyIndications:•Smaller lesions, < 1cm•Pigmented and small vascular lesions•Benign lesionsPrinciple: lesion and 2-3mm margin of normal tissue is excised

Excisional Biopsy

Excisional BiopsyElliptical incision is carried-out allowing for a narrow rim of normal peripheral tissue

Excisional BiopsyBeveling your incisions to a narrow “V” base facilitates wound closure

Drill biopsy

This type of biopsy is used mainly for intra-osseous

lesions

A drill in a dental engine is used to remove a core

from the centre of the tumour

Fine needle aspiration biopsy

Aspiration of cells or fluid for subsequent analysisTechnique consists of repeatedly passing a needle, under negative pressure, through a lesion to collect cells. The technique is usually indicated for lesions of major salivary glands and neck massesFluid aspirated from a lesion can also be sampledGenerally requires analysis by a cytopathologist

Fine needle aspiration biopsy

Frozen sections

This is quick method of diagnosis that can be used during surgery to make sure that the margin of the lesion is clearFrozen sections for tumour diagnosis usually provide a rapid and highly reliable answer and the only problem may be that of conveying the specimen from theatre to laboratory rapidly and without deterioration

Why not excise potentially malignant lesions?

Resection of a malignant lesion requires removal of a significant margin of normal tissue. Inadequate margins means recurrence. The margins of resection are determined by visual inspection and palpation of the lesion. This is very difficult to do if the lesion is gone!

Oral biopsy, how?

Local anesthesiaCareful not to distort your margins

HaemostasisSponge > suction

IncisionScalpel/punch 2-3mm of normal tissue

Tissue HandlingGentle, do not crush your specimen

Oral biopsy, how?

Identification of marginsSutures for orientation

Specimen careGentle handling with forceps

ClosureUndermining as needed

Pathology SheetBe descriptive

Oral biopsy, how?

There are different procedures for undertaking oral biopsies. It has been widely accepted that scalpel is the best surgical instrument for obtaining oral biopsies. The use of CO2 laser is compromised by thermal cytological artifacts. The same is also applied to electrosurgical units (5)

Oral biopsy, how?

The biopsy should be large enough to include normal and suspicious tissue and for the pathologist to give a diagnosis without further specimens. Small samples are difficult to orientate and handle and certain processes as sample fixation may end in reduction of the size of the specimen

Oral biopsy, how?Samples must be oriented with a suture or a piece of paper, and introduced in a container with a fixing solution (10% formalin). The number and location of the biopsies will be decided on the basis of the clinical appearance of the lesion. If a lesion shows several areas where biopsy would be indicated, more than one sample should be taken. In these cases with precancerous or suspicious lesions, toluidine blue staining could be useful to choose the areas most relevant to biopsy

Toluidine blue stainingToluidine blue displays affinity for areas of dysplasia, malignancy and high cell turn over

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Errors to be avoided when taking oral biopsies Taking insufficient amount of tissue in extension and depth Pressing the sample with tweezers, producing tissue tears Infiltrating anaesthetic solution within the lesion Using an insufficient volume of fixing solution Inclusion of undesired material in the sample; glove powder, calculus, restorative materials, etc.

Please Remember Discovering a lesion is the first step to making a diagnosis If you find yourself 10 years into practice and you have not diagnosed any dysplasia, you are missing lesions guaranteed !! Not all tumors are cancers, and not all cancers are tumors Diagnosing cancer is as important as treating caries !!

1. Shafer WG, Hine MK, Levy BM. A Textbook of Oral Pathology, 3rd ed.,W W,B, Saunders Com. Pp 545,1974.

2. Karkera BV, et al. Biopsy: Clinical implications. J Dent Oral Hygiene. 3:106,2011. 3. Mota-Ramírez A , Silvestre F J , Simó J M. Oral biopsy in dental practice. Med Oral Patol Oral Cir Bucal.12:E504, 2007. 4. Oliver RJ, Sloan P, Pemberton MN. Oral biopsies: methods and applications. Brit Dental J. 16:329,2004. 5. Rosebush MS, et al. The Oral biopsy: Indications, techniques and special considerations. J Tenn Dent Assoc. 90,2010. 6. Siddiqui IA, et al. Role of toluidine blue in early detection of oral cancer. Pak J Med Sci Q. 22:184,2006.

References:

oral biopsy

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