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1 The use of biopsy in dental practice: The position of the American Academy of Oral and Maxillofacial Pathology By Raymond J. Melrose, DDS Janice P. Handlers, DDS Stanley Kerpel, DDS Don-John Summerlin, DMD Charles J. Tomich, DDS Featured in General Dentistry, September/October 2007 Pg Contact Us Send to a Friend Send to Printer Close Window Posted on Wednesday, August 22, 2007 Biopsy is the gold standard of diagnostic procedures. The American Academy of Oral and Maxillofacial Pathology has stated its position concerning biopsy use in dental practice, believing that using the procedure more frequently will enhance diagnosis and contribute substantially to the quest for more evidence-based practice. Biopsy is a technique within the scope of practice of general dentists. It is vital to understand that biopsy is a tool for the diagnosis of myriad benign and malignant oral conditions. More frequent use of biopsy in dental practice will likely reduce the number of successful lawsuits brought for delay or failure to diagnose. This article offers 10 guidelines to dentists to help assure the success of the procedure. Received: December 15, 2006 Accepted: February 20, 2007 The American Academy of Oral and Maxillofacial Pathology (AAOMP) recommends that any abnormal oral tissue removed from a patient be submitted promptly for microscopic evaluation and diagnosis, preferably by an oral and maxillofacial pathologist.1 Exceptions to this recommendation may include tori, exostoses, and alveolar bone removed for prosthetic reasons; carious or periodontally involved teeth without attached soft tissue; radiographically normal impacted teeth with no soft tissue attached; and clinically normal appearing tissues removed for crown lengthening, periodontal pocket depth reduction, or functional or cosmetic purposes. Nonsubmission of abnormal tissue may result in patient care that is only partially evidence-based.1 Biopsy is defined as the removal for diagnostic study of a piece of tissue from a living body.2 Biopsy has been used for more than 150 years to establish the diagnosis of an unknown medical condition. It can be stated with certainty that biopsy also is the oldest and most reliable method currently available that can establish the definitive diagnosis of a clinical abnormality in dentistry. Although specialized techniques such as immunofluorescence, immunohistochemistry, and electron microscopy have deepened and extended the diagnostic reach that a biopsy can provide, none can be implemented without a piece of tissue. The practice of modern dentistry and medicine increasingly demands evidence-based treatment decisions and therapeutic outcomes. Nothing is more basic to initial treatment decisions and subsequent follow-up care than determining an accurate diagnosis. In 2001, the American Association of Oral and Maxillofacial Surgeons (AAOMS) stated that [e]vidence-based medicine demonstrates that treatment decisions and their outcomes should be based on a definitive pathologic diagnosis obtained either by preoperative biopsy or post-treatment submission of surgical specimens. 3 Three years later, the American Association of Endodontists (AAE) announced: A biopsy is appropriate if any of the following conditions exist: A) When an adequate amount of tissue or foreign material can be removed from the surgical site for histopathologic examination. B) Persistent pathosis or pathosis inconsistent with endodontic disease is noted on clinical or radiographic examination. C) Medical history indicates the merits of biopsy. 4 1 of 8

2 These statements from two respected dental specialty organizations strongly support the position of the AAOMP. What these dental specialty organizations recommend to their members is equally applicable for general dentists or for other specialists who may remove abnormal tissue in the course of patient care. Performing a biopsy procedure is well within the scope of training and ability for a general dentist. However, individuals who elect to perform biopsies in clinical practice must determine their comfort level with the various types of biopsy and develop criteria to refer patients to those with more biopsy experience. The most important issue, however, is not who should perform the procedure but when it should be recommended to patients. In this regard, several myths surrounding biopsy may discourage dentists from recommending the procedure in some cases and may reduce the likelihood of patient acceptance. First and foremost among these myths is the notion that a biopsy is used only to test for cancer. Patients fear that biopsy will disclose cancer, while dentists labor under the mistaken notion that the only reason to biopsy is to rule out cancer. It is correct that a cancer diagnosis typically is based on a biopsy but the real purpose of a biopsy is to determine a definitive diagnosis, which often cannot be established from clinical findings alone. Cancer is merely one of hundreds of diagnoses that can be made from biopsy examinations. The authors surveyed the records of several large oral and maxillofacial pathology laboratory practices and discovered that cancer represented less than 1.0% of all diagnoses made. However, too many oral cancer cases continue to be diagnosed at an advanced stage because biopsy was not recommended or performed when the first signs of disease were detected.5 A second myth is that the diagnosis of common conditions does not require biopsy verification because the judgment and experience of the clinician are sufficient. This approach raises concerns of clinical bias, which says that if a lesion looks like Disease X it most likely is Disease X and treatment is based on that diagnosis. However, the treatment is based on a premise that is not substantiated and cannot be proved except empirically (that is, by treatment that yields a satisfactory result). This approach has a long history in the management of conditions like dental caries and periodontal disease but it does not satisfy the need for better evidence-based decisions regarding other diseases. In addition, it may lead the dentist to place undue reliance on a single working diagnosis without considering plausible alternatives. Errors in judgment are more likely to occur if dentists do not consider alternative diagnoses. Conversely, performing a biopsy to establish a definitive diagnosis does not relieve the clinician of the need to consider a differential. Biopsy is not intended to be a substitute for thoughtful evaluation of the patient s condition. Tissue submitted for microscopic examination should be accompanied by a clinical diagnosis. This is valuable for the pathologist because it gives him or her an idea of what the dentist is seeing and thinking. In the great majority of cases, the diagnosis returned by a pathologist should be completely consistent with that clinical diagnosis; if it is not, the dentist should contact the pathologist to ensure that a laboratory error has not occurred. This study surveyed the records of three large oral and maxillofacial pathology laboratory practices, evaluating 1,500 consecutive cases (500 cases per laboratory) by looking at the rate of concordance between clinical and histopathologic diagnoses. For purposes of this article, concordance was defined as essential agreement; that is, the pathologic diagnosis rendered for the biopsy material did not require substantially different treatment or prognosis when compared to the clinical diagnosis. The concordance rate was 90.7%. There was remarkable similarity among the three laboratories findings. The variance of nearly 10% between clinical and histopathologic diagnoses is significant; however, it should be noted that the clinicians who performed the biopsies promptly learned of the correct diagnoses. The principal diagnoses that were not suspected clinically included squamous cell carcinoma, epithelial dysplasias/carcinoma in situ, odontogenic keratocyst, ameloblastoma, salivary gland tumors, and lichenoid mucositis. The latter often was commonly misinterpreted clinically as lichen planus or leukoplakia. Figures 1 4 offer examples of cases for which there was not essential agreement between clinical and histopathologic diagnoses. By contrast, some cases that were thought to be serious diseases (such as carcinoma) actually represented ulcers or inflammatory processes. 2 of 8

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4 The results from this laboratory survey are similar to those reported by Czerninski et al, who studied 136 cases of mucosal diseases and found a 78% overall rate of agreement between clinical and histopathologic diagnoses.6 The highest rate of agreement in their report was found in vesiculo-erosive diseases, while the lowest rate was observed in cases described as nonspecific ulcerative/inflammatory lesions. 4 of 8

5 Benefits that result when the submitted clinical diagnosis and the pathologic diagnosis correlate include increased confidence on the part of the clinician in his or her diagnostic skill, increased patient respect, and satisfaction that the treatment performed was appropriate. In addition, the written diagnosis usually brings closure to the clinical situation. Although it may be disconcerting when an unsuspected and/or serious diagnosis is rendered, both patient and doctor can readily appreciate the benefits of a timely, correct diagnosis. Failure to diagnose oral disease is a leading cause of legal action against dentists.7 A 2006 study regarding medical malpractice claims noted that missed or delayed diagnoses represented the grounds for lawsuits in 30% of 1,452 settled malpractice claims.7 Only claims that related to surgical misadventures represented a larger proportion (31%) of cases.8 By instituting practice guidelines that are in consonance with the AAOMP position on routine submission of tissues, clinicians can substantially protect themselves from the risk of a successful lawsuit based on failure to diagnose. From a practical standpoint, the two most commonly used types of biopsy are excisional and incisional. Fine needle aspiration biopsy, the cytobrush technique, and exfoliative cytology (PAP smear) are adjunctive techniques and will not be discussed in this article because they do not produce a definitive diagnosis. An excisional biopsy is a surgical procedure that removes the entire clinical abnormality for microscopic examination. An incisional biopsy is a surgical procedure that removes only a representative portion of the abnormality. The principal purpose of both types of biopsy is the establishment of a definitive diagnosis. An excisional biopsy may be employed to remove an undiagnosed abnormality. In this clinical setting, it is considered to be the correct treatment for the presumptive clinical diagnosis. An excisional biopsy also may be used to ensure that a previously diagnosed lesion has been removed completely and thus represents definitive treatment for that condition. The clinical decision to perform one type of biopsy over the other is based partly on the diagnosis that is considered to be most likely, partly on anatomic considerations, and partly on the doctor s experience and comfort level. The decision to perform a biopsy or to refer the patient to a specialist for the procedure is based on similar considerations. It is completely acceptable for clinicians to decide that they do not wish to perform biopsies in their practices, provided the necessity of biopsy is not ignored. Oral and maxillofacial pathologists rely on their dental and medical contributors for several important factors: that the tissues they examine and diagnose are representative of the patient s disease; that tissues are provided in sufficient quantity to ensure that the diagnosis is likely to represent what actually is occurring; and that the artifacts routinely induced during surgical tissue removal are minimized. Suggestions that will improve the result of the procedure are listed below. Methods for optimum results Biopsy site selection Site selection typically is not a concern for an excisional biopsy procedure. Incisional biopsies should try to include as much as possible of what appears to be the disease process. For large lesions or those with variable features, it may be wise to select several sites to biopsy to provide sufficient sampling. Including a border of clinically normal tissue at the expense of sufficient abnormal tissue may produce a less conclusive result. Because the purpose of an incisional biopsy is to establish a definitive diagnosis, providing sufficient abnormal tissue should be the chief focus. Ulcers often are found as a component of mucosal problems. When an ulcer is present, including adjacent, non-ulcerated tissue in the specimen is more likely to improve the diagnostic yield. When tissue sloughing is part of the problem, dentists should select an atraumatic, thin suture and pass the suture first through the sloughing surface tissue into the submucosa and out through a non-sloughing tissue surface. Use the suture to handle the tissue during the surgical procedure, remove the needle, and place the specimen (including the suture) in the container. It is not necessary to knot the suture. The suture prevents loss of sloughing tissue, both intraoperatively and during specimen transport. Remove sufficient tissue It is a good rule to excise small lesions rather than subject them to incisional biopsy. For incisional biopsies, it is best to provide the pathologist with as large a sample as is consistent with care for the 5 of 8

6 patient s postoperative comfort. Tiny samples may inhibit the histology technician from producing a quality slide and also may impair the pathologist s ability to provide an unequivocal diagnosis. When it is important for the pathologist to examine and comment on the lesion s margins of excision, the margins must be identified clearly. Using one or more sutures often is the simplest method. Incisional biopsy of swellings should take into account that a deep biopsy usually is more representative than a shallow one. A biopsy of solid bony lesions may be a challenge, although a trephine instrument can be helpful. Instruments now available for coring out bone for implant placement are excellent tools for many bone biopsies. Handle the specimen gently Do not grasp a soft tissue mass with a clamp, as this will crush the specimen. For a difficult site, such as the soft palate or pharynx, a suture should be used to handle or control a specimen. It usually is preferable to use a sharp cutting instrument (rather than one that induces heat) to remove a specimen. The heat produced by laser or cautery instruments induces artifact on the surface (and sometimes into the depth of the specimen) that may interfere with evaluation. Avoid the use of solutions that stain the surface Using colored antiseptics or similar materials to clean the surface or outline the incision on an oral mucosal site is not recommended. Conversely, substances like toluidine blue (tolonium blue) do not interfere with staining. Immediately place the specimen in the fixative provided Most oral pathology laboratories will provide bottles containing formalin for the fixation of tissue. Formalin is considered the standard fixative. Fixation is mandatory to inhibit autolysis of tissues once they are removed from the patient. Neither water nor saline solution will preserve tissue. Do not change or dilute the fixative unless instructions are given. Specimens that are to be submitted for immunofluorescence testing should not be placed in formalin; in such situations, the solution provided by the laboratory should be used. Diluting alcohol with water to 40 50% is less satisfactory because it dehydrates the tissues substantially. Formalin is a dilute solution of formaldehyde buffered to neutral ph. Formaldehyde is considered a toxic substance and a carcinogen when used inappropriately but it is not a significant risk in the very small quantities found in biopsy containers. However, bottles should remain tightly closed until use and should be resealed tightly before they are shipped to the laboratory. Follow the laboratory shipping directions that meet U.S. Postal Service or commercial shipper requirements. Clearly identify specimens from separate oral sites or place them in separate containers When more than one specimen is taken for examination, it may not be possible to identify the separate sites unless the specimens are identified, such as with a suture or by placing each one in a separate specimen container. If the sites cannot be identified precisely, it may not be possible to correlate the diagnoses with the specific sites. Submit a brief, thorough history and radiographs as appropriate Oral and maxillofacial pathologists are dentists with specialty training in pathology. Examining a piece of tissue under the microscope is not a task performed in isolation. To diagnose a specimen properly, the oral pathologist may need to review the clinical history and the setting in which the patient s condition manifested. The evaluation of pertinent radiographic images often is invaluable for proper disease classification and diagnosis. These factors are among the reasons why the knowledge of an oral and maxillofacial pathologist often is beyond that of an otherwise completely competent medical pathologist. Oral pathologists understand dentistry and they converse easily in dental terminology. They are going to use diagnostic terminology familiar and useful to dentists. Submit legible and complete paperwork Legibility requires no explanation. Complete paperwork means that the doctor or a designated staff person familiar with the forms used by the laboratory takes responsibility for completing the entire form. 6 of 8

7 The information requested is not superfluous. The federal and state regulations that apply to pathology laboratories demand that patients be uniquely identifiable to the greatest possible degree, consistent with HIPAA requirements. This is not intrusion on privacy; rather, it is for patient protection. The information provided as history is treated with similar discretion. Forward the specimen to the laboratory promptly The laboratory usually will provide a method for returning the specimen. Do not delay in sending it, as this will only delay the receipt of the result. Tissues placed in formalin for prolonged periods remain in diagnostic condition but it serves no useful purpose to hold them. Always correlate the diagnosis received with the clinical impression This is one of the most important caveats of biopsy. If a dentist receives a diagnosis that does not correlate substantially with the clinical situation, it is the doctor s responsibility to investigate. The easiest way to do this is to telephone the laboratory and talk directly with the oral pathologist. He or she will investigate and determine if a laboratory error has occurred or if the diagnosis is correct but unsuspected. Oral and maxillofacial pathology laboratories can be found in most portions of the United States. The laboratories can receive specimens from anywhere in the country that is served by the U.S. Postal Service. A list of the names, addresses, and directors of all oral and maxillofacial pathology laboratories in the U.S. and Canada can be found at the AAOMP Web site.9 Summary The routine submission of abnormal tissue to an oral and maxillofacial pathologist for diagnosis is a vital link in the development of truly evidence-based clinical practice. Biopsy is a simple, reliable, and indispensable tool in the practice of dentistry and medicine. Biopsy is not a panacea for protection against claims of malpractice but the timely and routine use of biopsy in the dental setting likely will substantially reduce the success rate of claims. It is eminently more satisfying for a doctor to know that he or she has a correct diagnosis upon which to base treatment than to plan treatment predicated on the assumption that a clinical diagnosis is accurate. Author information Dr. Melrose is a Fellow and Past President, American Academy of Oral and Maxillofacial Pathology and co-owner of Oral Pathology Associates, Inc. in Los Angeles, California. Dr. Handlers is co-owner of Oral Pathology Associates. Dr. Kerpel is Associate Director of Oral Pathology Laboratory, Inc. in Queens, New York, and Associate Director, Section of Oral Pathology residency training program, New York Hospital Queens. Dr. Summerlin is a professor, Department of Oral and Maxillofacial Pathology, Indiana University in Indianapolis. Dr. Tomich is a Past President, American Academy of Oral and Maxillofacial Pathology, currently in private practice for oral pathology in Indianapolis. References 1. Tissue submission policy. Available at: Accessed May Webster s Universal College Dictionary. New York: Random House, Inc.;1997: American Association of Oral and Maxillofacial Surgeons. Parameters and pathways: Clinical practice guidelines for oral and maxillofacial surgery; diagnosis and management of pathologic conditions. Chicago; American Association of Endodontists. Guide to clinical endodontics. Chicago; Jemal A, Siegel R, Ward E, Murray T, Xu J, Smigal C, Thun MJ. Cancer statistics, CA Cancer J Clin 2006;56: Czerninski T, Nadler C, Kaplan I, Regev E, Maly A. Comparison of clinical and histologic diagnosis in lesions of oral mucosa. Essay presented at: Annual Meeting of the American Academy of Oral and Maxillofacial Pathology;April 24,2006; San Antonio, TX. 7. Rapp C. Oral cancer malpractice claims increasing. Today s FDA 2005;17: Studdert DM, Mello MM, Gawande AA, Gandhi TK, Kachalia A, Yoon C, Puopolo AL, Brennan TA. Claims, errors, and compensation payments in medical malpractice litigation. N Engl J Med 2006;354: of 8

8 9. Biopsy services. Available at: Accessed May General Dentistry, September/October 2007, Volume 55, Issue 5 Rate it! Rate & Comment Rate Average (0 votes) Contact Us Send to a Friend Send to Printer Close Window 8 of 8