You are in: eMedicine Specialties > Otolaryngology and Facial Plastic Surgery > HEAD AND NECK ONCOLOGY Fine-Needle Aspiration of Neck MassesArticle Last Updated: Jan 14, 2008AUTHOR AND EDITOR INFORMATIONSection 1 of 10
  Author: Jonas T Johnson, MD, FACS, Professor and Chairman, Department of Otolaryngology, University of Pittsburgh School of Medicine; Professor, Department of Radiation Oncology, Professor, Department of Oral Maxillofacial Surgery, University of Pittsburgh School of Dental Medicine Jonas T Johnson is a member of the following medical societies: Allegheny County Medical Society, American Academy of Otolaryngology-Head and Neck Surgery, American Association for Cancer Research, American Bronchoesophagological Association, American College of Surgeons, American Head and Neck Society, American Laryngological Association, American Laryngological Rhinological and Otological Society, American Medical Association, American Radium Society, American Rhinologic Society, American Society of Clinical Oncology, Association of Military Surgeons of the US, Pennsylvania Medical Society, and Society of University Otolaryngologists-Head and Neck Surgeons Coauthor(s): Lee Zimmer, MD, PhD, Staff Physician, Department of Otolaryngology, University of Pittsburgh Medical Center Editors: David J Terris, MD, FACS, Porubsky Professor and Chairman, Department of Otolaryngology, Medical College of Georgia; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine; Nader Sadeghi, MD, FRCS(C), Associate Professor of Surgery, Director of Head and Neck Surgery, Department of Surgery, Division of Otolaryngology, George Washington University; Christopher L Slack, MD, Otolaryngology-Facial Plastic Surgery, Private Practice, Associated Coastal ENT; Medical Director, Treasure Coast Sleep Disorders; Arlen D Meyers, MD, MBA, Professor, Department of Otolaryngology-Head and Neck Surgery, University of Colorado School of Medicine Author and Editor Disclosure Synonyms and related keywords: fine-needle aspiration for neck masses, FNA, fine needle aspiration, fine-needle aspiration and biopsy, fine-needle aspiration biopsy, neck masses, solitary neck mass, Hodgkin lymphoma, Hodgkin’s lymphoma, neck tumor, neck cancer INTRODUCTIONSection 2 of 10
  Physicians are often asked to evaluate a patient with a solitary neck mass. Clinical evaluation of a solitary neck mass can be difficult because of the extensive differential diagnoses (listed below). An important factor in determining the differential diagnoses is the age of the patient. Individuals younger than 40 years are overwhelmingly diagnosed with benign processes such as congenital and inflammatory lesions. In patients older than 40 years, the differential diagnoses shift, as more than 60% of lesions are associated with malignancy. Differential diagnoses of neck masses
Evaluation of a patient with a neck mass should always begin with a thorough history, followed by a complete head and neck examination. The entire mucosal surface of the upper aerodigestive tract requires special attention. If the physical examination does not explain the neck mass, a fine-needle aspiration (FNA) of the neck mass may be performed. If the mass is believed to be a metastatic lesion, a panendoscopy of the aerodigestive tract is warranted. FNA for cytologic evaluation of a neck mass was first reported by Kun in 1847. However, the procedure did not gain wide acceptance in medicine at that time. In the 1930s, Memorial Sloan Kettering rediscovered the utility of needle biopsy of head and neck masses. The use of large-bore needles at that time led to frequent complications, one of which was occasional seeding of the tumor along the biopsy tract. The frequent morbidity associated with this procedure prevented widespread acceptance of this technique in other centers of METHODSection 3 of 10
Fine-needle aspiration (FNA) is a simple office procedure that requires a few minutes to complete. It is ideal to have the cytotechnologist and pathologist available at the time of the aspiration. This allows an immediate assessment of the adequacy of the specimen. If insufficient cells have been obtained, the aspirate can be repeated. Sometimes the diagnosis can be made immediately. A small drop of aspirated fluid is placed on a glass slide (see Image 2). A smear is made by laying another glass slide on top of the drop of fluid and pulling the slides apart to spread the fluid (see Image 1). Wet smears are placed in 95% ethyl alcohol and treated with the Papanicolaou technique and stains. These stains offer excellent cellular detail and may indicate the cellular origin of a metastatic tumor. Specimens should be air dried and prepared for Wright-Giemsa stain when the differential diagnosis includes salivary, lymphoproliferative, and/or fatty tumors. The following common technical errors lead to inadequate specimens:
Other nontechnical errors of specimen collection include the collection of necrotic and/or fibrotic specimens. Some debate exists about what constitutes an adequate specimen for cytopathological diagnosis by FNA. At least several clusters of 8-10 cells are needed for interpretation. A review of the literature reveals that 7-45% of FNA specimens are inadequate for pathological diagnosis.1, 2 The Papanicolaou society states that inadequate specimens should not exceed 15%. When aspirates are placed on slides, clusters of cells form. Clusters contain approximately 10 cells. In a 1997 review of FNA of breast masses, Layfield and colleagues indicated that FNA smears with 6 or more cell clusters decrease the false-negative rate to 2.1% and decrease the percentage of inadequate specimens to 13.7%.3 However, if slides that contain fewer than 6 clusters of breast tissue were excluded, 40% of true-negative and 4.5% of true-positive slides would be lost to analysis. The authors conclude that sampling adequacy should be based on the confidence of needle placement, cell preservation, and correlation with clinical findings. ADVANTAGES OVER OPEN BIOPSYSection 4 of 10
Fine-needle aspiration (FNA) has several advantages over excisional biopsy. In today's economic environment, cost savings is an important consideration in medicine. The cost of FNA in the office varies from $75 to $350 depending on the study source and whether or not the pathology fees are included. In contrast, the cost of an excisional biopsy ranges from $1200-2500. The cost is even higher if a hospital stay is required. FNA is also more convenient for patients and their families. The procedure requires only an office visit with minimal loss of time from work. On the other hand, excisional biopsy often requires time off from work, preoperative blood tests, and often, radiographic and cardiac testing. Furthermore, surgery exposes patients to the risks of anesthesia, postoperative infection, and the possibility of tumor seeding (see below). A percentage of patients may require overnight admission to the hospital and extra time from work. Questions arise as to whether FNA and/or excisional biopsies can lead to tumor seeding along the needle tract. Studies have demonstrated significant tumor spillage following large-bore tissue core biopsies. Tumor seeding requires creation of larger soft tissue deficits to remove the tumor in its entirety. Furthermore, tumor seeding in avascular planes renders cells more resistant to radiotherapy and chemotherapy. In 1983, Ryd and colleagues demonstrated 100-10,000 tumor cells in the needle tract of mouse hind legs following FNA (with a 21-gauge needle) of tumors labeled with iododeoxyuridine I 125 (125-IUDR).4 This risk of tumor spillage during FNA has not been confirmed in human studies. In 1985, Qizalbash and colleagues lined FNA biopsy tracts in humans with LIMITATIONS OF FINE-NEEDLE ASPIRATIONSection 5 of 10
Fine-needle aspiration (FNA) for head and neck masses has several limitations. Failure to establish an accurate diagnosis may be because of sampling error. In these circumstances, repeat aspiration is suggested, and excisional biopsy may be considered. Personnel responsible for handling, processing (experienced cytotechnologist), and reading (cytopathologist) FNA samples must be well trained. Interobserver variability must be minimized. In 1989, Peters and colleagues demonstrated an interobserver variability of 8% in diagnosis of FNA specimens, with a specificity of 96% and a sensitivity of 97%.7 FNA was most accurate at diagnosing epithelial cysts and epidermoid malignancies. FNA was least effective at distinguishing lymphoid hyperplasia and chronic inflammation from lymphoma. If any questions exist regarding interpretation of the aspirate, decisions on surgery, radiation, and chemotherapy should be deferred until the mass is accurately diagnosed. Finally, using FNA under the appropriate conditions is important. FNA complements clinical diagnosis and should not be considered a substitute for a thorough history and physical examination. GENERAL RESULTS OF FINE-NEEDLE ASPIRATIONSection 6 of 10
As mentioned in the beginning of the article, interest in fine-needle aspiration (FNA) in the diagnosis of neck masses has increased. Scandinavian success with FNA has been replicated by several large American studies for the head and neck. In 1982, Frable and Frable reviewed the success of FNA in 567 patients with neck masses.8 Since then, multiple reports of experience with FNA in the diagnosis of head and neck lesions have been published. Sensitivity and specificity rates are approximately 85-90%.7 This means the incidence of false-negative and false-positive results range from 10-15%. FNA is not a substitute for excisional biopsy but should be considered an additional diagnostic tool to be used concurrently with patient history, physical findings, and laboratory tests. Selective use of ultrasound ( SELECTIVE RESULTS WITH FINE-NEEDLE ASPIRATIONSection 7 of 10
Although fine-needle aspiration (FNA) may not be the method of choice for all neck masses, studies demonstrate a specific advantage of FNA for the diagnosis of several specific disease entities. In 1990, Schwarz and colleagues demonstrated that FNA had an overall sensitivity of 92% and a 100% positive predictive value for the diagnosis of squamous cell carcinomas (SCCs) of the head and neck.10 In a 1991 report, Birchall and colleagues further demonstrated that FNA of neck masses was 100% specific for SCCs of the neck.11 The predictive power of FNA in diagnosing head and neck SCCs allows physicians to narrow the search for the primary tumor. The prevalence of thyroid nodules may approach 70% in the population.13 Incidence varies by age and method of detection. Incidence of carcinoma in thyroid nodules varies from 3-5%. Approximately 10-26% of all patients with thyroid malignancies present with an isolated neck Many studies have examined the use of FNA in the diagnosis of masses suspicious for thyroid malignancies. In 1991, Klemi and colleagues examined 186 aspirates from the thyroid gland.14 Among histology-confirmed cases, FNA of thyroid nodules had a specificity of 100%, sensitivity of 55%, and accuracy of 95%. In 1985, Jayarman and colleagues studied 308 cases of solitary thyroid nodules with FNA.15 The pathological diagnosis was correctly established from aspirates in 207 of 216 (95.8%) colloid adenomatous goiters. Hashimoto thyroiditis was diagnosed in 7 of 10 patients. Follicular adenomas were diagnosed as follicular neoplasms in 11 of 11 patients. However, only 4 of 19 follicular carcinomas were accurately diagnosed using FNA. The false-negative rate for follicular carcinoma varies from 2.4-5.3%. Without the tumor capsule, the angioinvasive character of follicular carcinoma cannot be determined. The difficulty in distinguishing benign from malignant has led to the term follicular neoplasm. Because of the difficulty in differentiating follicular adenoma from well-differentiated follicular carcinoma with FNA, the presence of a follicular neoplasm with FNA is an indication for thyroid surgery. Use of FNA for isolated salivary gland masses is broadly accepted. Nevertheless, surgeons are cautioned to interpret the result of FNA with the clinical situation. Both false-negative and false-positive results are encountered. Interpretation of salivary gland pathology is more unusual (may be "pleomorphic") and requires greater experience than some other neck masses. In 2000, Costas et al studied 112 aspirations from salivary glands. Their results were less rewarding, with a sensitivity and specificity of 84.8% and 93.7%, respectively. Cohen et al (2004) reported FNA in 169 salivary masses.16 A satisfactory specimen was obtained in 89%. In lesions found to be malignant on final histologic examination, positive and negative predictive values were 84% and 77%, respectively. These results suggest that FNA alone may not be sufficient to rule out salivary malignancies and that further clinical evaluation, including surgical resection, may be necessary. Most reports acknowledge a low but important incidence of false-positive aspirates. These authors warn that the predictive value of a negative aspirate is low. When clinical suspicion warrants it, further sampling (eg, excisional biopsy) is appropriate. Some reports have suggested that Hodgkin lymphoma can be accurately diagnosed by FNA. Hodgkin lymphoma is suggested by the presence of Reed-Sternberg cells in the setting of numerous lymphocytes on FNA. However, because this cell type is found in other conditions (eg, non-Hodgkin disease of the large-cell type), pathological identification of Hodgkin disease still requires additional tissue for surrounding cellular elements. The role of FNA in the diagnosis of non-Hodgkin lymphoma is controversial. The diagnostic yield of FNA is low because differentiating non-Hodgkin lymphoma from lymphocytic thyroiditis and anaplastic thyroid carcinoma is difficult. Future studies that combine FNA with flow cytometry and immunohistochemistry may increase the accuracy of lymphoma diagnosis without the need for excisional biopsies. Flow cytometry uses a beam of laser light to identify cell surface antigens. Tagged antibodies bind to cell surface antigens on lymphocytes, allowing the identification of non-Hodgkin lymphoma. Recently, flow cytometry has been used to help diagnose pathology on FNA. Cannon and Richardson in 2000 retrospectively examined the use of FNA and flow cytometry in 11 cases of isolated neck masses diagnosed as lymphoma.18 FNA of the 1 patient with Hodgkin disease favored a mesenchymal neoplasm, and flow cytometry findings were noncontributory. In the other 10 patients, FNA indicated lymphoma in 7, and flow cytometry revealed clonal lymphocytic abnormalities in all 10, but open biopsies were obtained to more accurately characterize these lymphoid proliferations. FNA is routinely used for the histologic diagnosis of isolated neoplastic neck masses. However, use of FNA in the diagnosis of inflammatory lesions has been limited. FNA could likely be used to isolate individual organisms or at least allow for the culture of an offending organism. An array of case reports and case series has demonstrated a use for FNA in the diagnosis of infectious diseases of the neck. A few of the causes identified include Staphylococcus aureus, Escherichia coli, and Bacteroides fragilis; Cryptococcus, Mycobacterium, Coccidioides, Bacteroides, Streptococcus, Haemophilus, Pseudomonas, and Citrobacter species; and Cytomegalovirus infection, syphilis, and actinomycosis. Tuberculous lymphadenitis often manifests in the head and neck. FNA specimens have cytologic evidence consistent with tuberculosis. Eighty percent of FNA specimens positive for tuberculosis have been confirmed by open biopsy. FNA histology includes granulomatous inflammation and/or caseation necrosis. Cultures from 80% of specimens are positive for tuberculosis. The sensitivity of FNA for tuberculosis increased from 70-90% when combined with skin testing. Further studies are warranted to examine the role of FNA in the diagnosis of tuberculosis and other inflammatory lesions of the head and neck. FINE-NEEDLE ASPIRATION IN PEDIATRIC PATIENTSSection 8 of 10
Neck masses in children differ from those in adults. Children present more frequently with reactive inflammatory lymphadenopathy. Primary or secondary malignant involvement is rare in children. Unfortunately, the literature on fine-needle aspiration (FNA) in children is limited by small study size and varying results. Few studies have examined the utility of FNA in children with masses in the head and neck. In 1991, Silverman and colleagues examined 135 FNA specimens from multiple body sites in children.19 FNA had a sensitivity of 90.6%, a specificity of 100%, and a positive predictive value of 100%. They concluded that FNA allowed definitive diagnosis and therapy for malignant and/or infectious lesions in children. These conclusions cannot be carried over to head and neck lesions because only 7 FNA specimens were from the head and neck. However, the results lend support for further investigation of using FNA for the diagnosis of head and neck masses in the pediatric population. MULTIMEDIASection 9 of 10
REFERENCESSection 10 of 10
Fine-Needle Aspiration of Neck Masses excerpt Article Last Updated: Jan 14, 2008 | ||||||||||||||
