Principles and Techniques of Biopsy Modified By : DR. Mohamed Barakat
Principles and Techniques of Biopsy • It is important to develop a systematic approach in evaluating a patient with a lesion in the Oral and Maxillofacial region.
These steps include : • A detailed health history • A history of the specific lesion • A clinical examination • A radiographic examination • Laboratory investigations • Surgical specimens for histopathologic evaluation
Health History • An accurate health history may disclose predisposing factors in the disease process or factors that affect the patients management. • Up to 90% of systemic deseases can be discovered through history taking. • The same can be true of oral lesions when one is familiar with the natural progression of the more common disease processes.
Medical conditions that warrant special care include: • Congenital heart defects • Coagulopathies • Hypertension • Poorly controlled diabetics • Immunocompromised patients
Questions to Ask • Duration of the lesion • Changes in size and rate of change • Changes in the character of the lesion. • Lump to ulcer, etc • Associated systemic symptoms: • fever • nausea • anorexia
More Questions to Ask • Pain • Abnormal sensations • Anesthesia • A feeling of swelling • Bad taste or smell • Dysphagia • Swelling or tenderness of adjacent lymph nodes • Character of the pain if present
Historical Reasons for the Lesions: • Trauma to the area • Recent toothache • Habits
Clinical Examination • The clinical examination should always include when possible: • Inspection • Palpation • Percussion • Auscultation
Clinical Evaluation • The anatomic location of the lesion/mass • The physical character of the lesion/mass • The size and shape of the lesion/mass • Single vs. multiple lesions • The surface of the lesion • The color of the lesion • The sharpness of the boundaries of the lesion • The consistency of the lesion to palpation • Presence of pulsation • Lymph node examination
Radiographic Examination • The radiographic appearance may provide clues that will help determine the nature of the lesion. • A radiolucency with sharp borders will often be a cyst • A ragged radiolucency will often be a more aggressive lesion • Radiopaque dyes and instruments can help differentiate normal anatomy
Laboratory Investigation • Oral lesions may be manifestations of systemic disease. • If a systemic disease is suspected it should be pursued.
These include: • Tumor of hyperparathyroidism • Padgets disease • Multiple myeloma • Determination of serum calcium, phosphorus, and alkaline phosphatase and protein can be very useful in excluding certain pathological processes.
Indications for Biopsy • Any lesion that persists for more than 2 weeks with no apparent etiologic basis • Any inflammatory lesion that does not respond to local treatment after 10 to 14 days. • Persistent hyperkeratotic changes in surface tissues. • Any persistent tumescence, either visible or palpable beneath relatively normal tissue.
Indications for Biopsy • Inflammatory changes of unknown cause that persist for long periods • Lesion that interfere with local function • Bone lesions not specifically identified by clinical and radiographic findings • Any lesion that has the characteristics of malignancy
Characteristics of lesions that raise the suspicion of malignancy. • Erythroplasia- lesion is totally red or has a speckled red appearance. • Ulceration- lesion is ulcerated or presents as an ulcer. • Duration- lesion has persisted for more than two weeks. • Growth rate- lesion exhibits rapid growth • Bleeding- lesion bleeds on gentle manipulation • Induration- lesion and surrounding tissue is firm to the touch • Fixation- lesion feels attached to adjacent structures
What is a Biopsy? • Biopsy is the removal of tissue for the purpose of diagnostic examination.
Types of Biopsy • Oral cytology • Aspiration biopsy • Incisional biopsy • Excisional biopsy • Needle biopsy
Oral Cytology • Developed as a diagnostic screening procedure to monitor large tissue areas for dysplastic changes. • Most frequently used to screen for uterine cervix malignancy • May be helpful with monitoring postradiation changes, herpes, pemphigus.
The Disadvantage of oral cytological procedures include: • Not very reliable with many false positives. • Expertise in oral cytology is not widely available • The lesion is repeatedly scraped with a moistened tongue depressor or spatula type instrument. The cells obtained are smeared on a glass slide and immediately fixed with a fixative spray or solution.
Aspiration Biopsy • Aspiration biopsy is the use of a needle and syringe to penetrate a lesion for aspiration if its contents. • Indications: • To determine the presents of fluid within a lesion • To a certain the type of fluid within a lesion • When exploration of an intraosseous lesion is indicated
Aspiration • An 18 gauge needle on a 5 or 10 ml syringe is inserted into the area under investigation after anesthesia is obtained. • The syringe is aspirated and the needle redirected if necessary to find the fluid cavity.
Incisional Biopsy • An incisional biopsy is a biopsy that samples only a particular portion or representative part of a lesion. • If a lesion is large or has different characteristics in various locations more than one area may need to be sampled
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.
Excisional Biopsy An excisional biposy implies the complete removal of the lesion. • Indications: • Should be employed with small lesions. Less than 1cm • The lesion on clinical exam appears benign. • When complete excision with a margin of normal tissue is possible without mutilation.
Excisional Biopsy • Technique: • The entire lesion with 2 to 3mm of normal appearing tissue surrounding the lesion is excised if benign.
Anesthesia • Block anesthesia is preferred to infiltration • When blocks are not possible distant infiltration may be used • Never inject directly into the lesion
Tissue Stabilization • Digital stabilization • Specialized retractors/forceps • Retraction sutures • Towel Clips
Hemostasis • Suction devices should be avoided • Gauze compresses are usually adequate • Gauze wrapped low volume suction may be used if needed
Incisions • Incisions should be made with a scalpel. • They should be converging • Should extend beyond the suspected depth of the lesion • They should parallel important structures • Margins should include 2 to 3mm of normal appearing tissue if the lesion is thought to be benign. • 5mm or more may be necessary with lesions that appear malignant, vascular, pigmented, or have diffuse borders.
Handling of the Tissue Specimen • Direct handling of the lesion will expose it to crush injury resulting in alteration the cellular architecture.
Specimen Care • The specimen should be immediately placed in 10% formalin solution, and be completely immersed.
Margins of the Biopsy • Margins of the tissue should be identified to orient the pathologist. A silk suture is often adequate. Illustrations are also very helpful and should be included.
Surgical Closure • Primary closure of the wound is usually possible • Mucosal undermining may be necessary • Elliptical incision on the hard palate or attached gingiva may be left to heal by secondary intention.
Biopsy Data Sheet • A biopsy data sheet should be completed and the specimen immediately labeled. All pertinent history and descriptions of the lesion must be conveyed.
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.
Clinical Exam • Palpation of the area of the lesion with comparison to the opposite side. • 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
Principles of Surgery • 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 • Flaps should be full thickness • Major neurovascular structures should be avoided
Principles of Surgery • Osseous windows should be submitted with the specimen • Osseous preformations can be enlarged to gain access • Avoid roots and neurovascular structures • The tissue consistency and nature of the lesion will determine the ease of removal
Principles of Surgery • Incisional biopsies only require removal of a section of tissue • Soft tissue overlying the lesion should be reapproximated following thorough irrigation of the operative site. • The specimen should be handled as previously described
Biopsy Results: What If ? • They don’t corroborate your clinical impression • Repeat the biopsy!!! • Determine if the tissue was looked at by an Oral Pathologist • The results show malignancy
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