Note: This guideline has been updated. The National Guideline Clearinghouse (NGC) is working to update this summary.

Neck mass/adenopathy

To evaluate the appropriateness of initial radiologic examinations for patients with neck mass/adenopathy

Patients with neck mass/adenopathy

Utility of radiologic examinations in differential diagnosis

Literature Search Procedure

The Medline literature search is based on keywords provided by the topic author. The two general classes of keywords are those related to the condition (e.g., ankle pain, fever) and those that describe the diagnostic or therapeutic intervention of interest (e.g., mammography, MRI).

The search terms and parameters are manipulated to produce the most relevant, current evidence to address the American College of Radiology Appropriateness Criteria (ACR AC) topic being reviewed or developed. Combining the clinical conditions and diagnostic modalities or therapeutic procedures narrows the search to be relevant to the topic. Exploding the term "diagnostic imaging" captures relevant results for diagnostic topics.

The following criteria/limits are used in the searches.

1. Articles that have abstracts available and are concerned with humans.
2. Restrict the search to the year prior to the last topic update or in some cases the author of the topic may specify which year range to use in the search. For new topics, the year range is restricted to the last 5 years unless the topic author provides other instructions.
3. May restrict the search to Adults only or Pediatrics only.
4. Articles consisting of only summaries or case reports are often excluded from final results.

The search strategy may be revised to improve the output as needed.

The total number of source documents identified as the result of the literature search is not known.

Strength of Evidence Key

Category 1 - The conclusions of the study are valid and strongly supported by study design, analysis, and results.

Category 2 - The conclusions of the study are likely valid, but study design does not permit certainty.

Category 3 - The conclusions of the study may be valid, but the evidence supporting the conclusions is inconclusive or equivocal.

Category 4 - The conclusions of the study may not be valid because the evidence may not be reliable given the study design or analysis.

The topic author drafts or revises the narrative text summarizing the evidence found in the literature. American College of Radiology (ACR) staff draft an evidence table based on the analysis of the selected literature. These tables rate the strength of the evidence for all articles included in the narrative text.

The expert panel reviews the narrative text, evidence table, and the supporting literature for each of the topic-variant combinations and assigns an appropriateness rating for each procedure listed in the table. Each individual panel member forms his/her own opinion based on his/her interpretation of the available evidence.

More information about the evidence table development process can be found in the ACR Appropriateness Criteria® Evidence Table Development document (see "Availability of Companion Documents" field).

Modified Delphi Technique

When the data available from existing scientific studies are insufficient, the American College of Radiology Appropriateness Criteria (ACR AC) employs systematic consensus techniques to determine appropriateness. The ACR AC panels use a modified Delphi technique to determine the rating for a specific procedure. A series of surveys are conducted to elicit each individual panelist's expert opinion of the appropriateness of an imaging or therapeutic procedure for a specific clinical scenario based on the available data. ACR staff distributes surveys to the panelists along with the evidence table and narrative. Each panelist interprets the available evidence and rates each procedure. Voting surveys are completed by panelists without consulting other panelists. The ratings are integers on a scale between 1 and 9, where 1 means the panel member feels the procedure is "least appropriate" and 9 means the panel member feels the procedure is "most appropriate." Each panel member has one vote per round to assign a rating. The surveys are collected and de-identified and the results are tabulated and redistributed after each round. A maximum of three rounds are conducted. The modified Delphi technique enables each panelist to express individual interpretations of the evidence and his or her expert opinion without excessive bias from fellow panelists in a simple, standardized, and economical process.

Consensus among the panel members must be achieved to determine the final rating for each procedure. If eighty percent (80%) of the panel members agree on a single rating or one of two consecutive ratings, the final rating is determined by the rating that is closest to the median of all the ratings. Up to three voting rounds are conducted to achieve consensus.

If consensus is not reached through the modified Delphi technique, the panel is convened by conference call. The strengths and weaknesses of each imaging examination or procedure are discussed and a final rating is proposed. If the panelists on the call agree, the rating is accepted as the panel's consensus. The document is circulated to all the panelists to make the final determination. If consensus cannot be reached, "No consensus" appears in the rating column and the reasons for this decision are added to the comment sections.

Not applicable

A formal cost analysis was not performed and published cost analyses were not reviewed.

Criteria developed by the Expert Panels are reviewed by the American College of Radiology (ACR) Committee on Appropriateness Criteria.

Note: This guideline has been updated. The National Guideline Clearinghouse (NGC) is working to update this summary. The recommendations that follow are based on the previous version of the guideline.

Note from the American College of Radiology (ACR) and the National Guideline Clearinghouse (NGC): ACR has updated its Relative Radiation Level categories and Rating Scale. The Rating Scale now includes categories (1,2,3 = Usually not appropriate; 4,5,6 = May be appropriate; 7,8,9 = Usually appropriate). See the original guideline document for details.

ACR Appropriateness Criteria®

Clinical Condition: Neck Mass/Adenopathy

Variant 1: Adult presenting with a nonpulsatile solitary neck mass (afebrile).

Note: Abbreviations used in the tables are listed at the end of the "Major Recommendations" field.

Variant 2: Adult presenting with a solitary neck mass (febrile).

Note: Abbreviations used in the tables are listed at the end of the "Major Recommendations" field.

Variant 3: Adult presenting with a pulsatile neck mass.

Note: Abbreviations used in the tables are listed at the end of the "Major Recommendations" field.

Variant 4: Adult presenting with multiple neck masses.

Note: Abbreviations used in the tables are listed at the end of the "Major Recommendations" field.

Variant 5: Adult with a history of treatment for cancer presenting with a neck mass.

Note: Abbreviations used in the tables are listed at the end of the "Major Recommendations" field.

Variant 6: Child (up to age 14) presenting with a solitary neck mass or multiple neck masses (afebrile).

Note: Abbreviations used in the tables are listed at the end of the "Major Recommendations" field.

Variant 7: Child (up to age 14) presenting with a solitary neck mass (febrile).

Note: Abbreviations used in the tables are listed at the end of the "Major Recommendations" field.

Summary of Literature Review

Initial Diagnosis

Imaging may be requested in a patient who presents with a palpable neck mass. The clinical presentation may be variable, as the patient may be an adult or child, the mass may be painful, or the patient may be febrile. The type of initial imaging study that has been recommended has varied over the past 20 years with the development and maturation of new imaging modalities.

Magnetic Resonance Imaging (MRI) and Computed Tomography (CT)

In adults, a neck mass is likely to be either neoplastic or inflammatory. In older patients with a smoking history, the diagnosis is often malignancy. In adults who present with a fever, the etiology is often inflammation. Both CT and MRI can accurately diagnosis both disease entities. Multidetector CT (MDCT) now appears to be the preferred initial modality for evaluating a patient with a palpable neck mass. Both modalities can be used for initial diagnosis of a primary head and neck malignancy and for staging of cervical lymph nodes. However, the rapid image acquisition of MDCT reduces physiologic motion and produces a higher consistent image quality compared with MRI. MRI and CT are complementary studies, and MRI is superior to CT for soft-tissue characterization. MRI is also superior to CT for detecting perineural spread, which is important for initial staging for a variety of skull base tumors.

Use of Contrast

Intravenous contrast is recommended for routine cross-sectional imaging in adults or children presenting with a neck mass with no contraindications. Contrast is helpful for assessing tumor margins and is essential for detecting neck abscesses, especially those that are intramuscular. Intravenous contrast is also helpful for distinguishing vessels from lymph nodes and determining if the mass is hypervascular, as many "pulsatile" neck masses (especially those in level 2 or 3) are lymph nodes overlying the carotid rather than true vascular masses. Contrast can obscure visualization of sialoliths and noncontrast CT is recommended in patients presenting with a neck mass felt to be due to an obstructing sialolith. MRI may be helpful in patients with nonmineralized sialoliths. Iodine-based contrast may be avoided in patients with thyroid cancer history or when metastatic thyroid cancer is suspected.

Positron Emission Tomography (PET)

The role of PET combined with CT for assessing neck masses is evolving. Some investigators feel that it is superior to CT alone for evaluating primary site tumor margins. It is also superior to CT alone for staging cervical lymph nodes. However, it cannot detect lymph node micrometastases. Currently PET/CT is not routinely recommended for initial staging of all patients with head and neck squamous cell carcinoma (HNSCCA).

Ultrasound (US)

The use of US for the initial diagnosis of neck masses in adults and children is steadily increasing. In fact, the overall use of neck US in the United States has generally lagged its use in Europe and Southeast Asia, due in part to greater accessibility of cross-sectional modalities such as CT and MRI here. US is useful in differentiating between solid cystic neck lesions in both adults and children and is also helpful in discriminating between high-flow and low-flow vascular malformations. US is also very helpful for image-guided biopsies of nonpalpable or small lesions that are relatively superficial and for biopsies of indeterminate soft tissue in the treated neck. Studies have shown that US fine-needle aspiration of lymph nodes can be useful in staging the N0 neck. The positive predictive value of this technique is high; however, concern has been raised regarding its negative predictive value and its inability to exclude micrometastases. Some studies have suggested that color Doppler US can distinguish between metastatic and inflammatory neck nodes. Although these results are promising, the results appear to be user dependent.

Angiography

The role of conventional angiography for initial diagnosis is very limited. The initial imaging modality for evaluating a pulsatile neck mass (glomus tumor, aneurysm) is CT angiography, which now appears to be preferred to MR angiography for these indications. Conventional angiography is used for planning endovascular treatment (tumor embolization, balloon test occlusion, etc.) or for further characterization of vascular neck lesions.

Neck Masses in Children

In children who present with neck masses, one must also consider congenital etiologies in addition to neoplasia and inflammation. Because of the risk of sedation and radiation dose, there is some debate as to the recommended imaging study in a child with a neck mass. In children suspected of having a congenital abnormality, US is often performed as it is sufficient for distinguishing a cystic from a solid mass. Color-flow Doppler US is also helpful for characterizing flow in solid lesions. Either CT or MRI can be performed in children suspected of a having a malignancy or a deep neck abscess that may require surgical drainage. Although it does emit radiation, MDCT tends to be preferred over MRI due to the lower sedation requirements resulting from shorter examination time.

Post-treatment

CT and MRI are beneficial in patients previously treated for HNSCCA. Both modalities can evaluate the extent of locoregional recurrence and evaluate for synchronous lesions in the neck. MRI is superior to CT for characterizing soft tissue and detecting perineural spread. However, due to the length of the examination, MRI is more likely to be degraded by motion artifact in patients treated for advanced disease who have developed severe post-treatment mucositis and have difficulty with pooling of secretions. New physiologic techniques such as diffusion-weighted MRI, MR spectroscopy, and MR and CT perfusion have shown promise in attempting to differentiate recurrent tumor from post-treatment changes. However, the results are preliminary, and further investigations are required.

The current literature suggests that PET/CT may be superior to CT or MRI for detecting recurrent tumor. It has the advantage of detecting recurrent HNSCCA based on correlation of anatomic distortion with physiologic abnormality. The sensitivity and specificity of PET/CT for detecting recurrent HNSCCA are in the range of 70% to 100%. However, one must be aware of the range of physiologic activity following treatment to avoid false positive results. Although PET/CT is commonly used to evaluate post-treatment HNSCCA patients, there is no consensus regarding the proper timing of serial post-treatment surveillance studies. The imaging study that is ordered should depend on the clinical indication of the patient and an understanding of the information that the imaging study can provide.

Summary

• CT and MRI are complementary methods for evaluating a patient with a palpable neck mass.
• MDCT is emerging as the preferred modality for the initial diagnostic imaging workup.
• Although PET/CT is not routinely recommended for initial staging of patients with HNSCCA, it may be useful in staging and problem solving in these patients.
• US is increasingly demonstrating usefulness in differentiating solid and cystic neoplasms, in assessing vascular lesions, and in facilitating biopsies.
• CT, MRI, and PET/CT are useful in evaluating the post-treatment cancer patient.

Anticipated Exceptions

Nephrogenic systemic fibrosis (NSF) is a disorder with a scleroderma-like presentation and a spectrum of manifestations that can range from limited clinical sequelae to fatality. It appears to be related to both underlying severe renal dysfunction and the administration of gadolinium-based contrast agents. It has occurred primarily in patients on dialysis, rarely in patients with very limited glomerular filtration rate (GFR) (ie, <30 mL/min/1.73 m²), and almost never in other patients. There is growing literature regarding NSF. Although some controversy and lack of clarity remain, there is a consensus that it is advisable to avoid all gadolinium-based contrast agents in dialysis-dependent patients unless the possible benefits clearly outweigh the risk, and to limit the type and amount in patients with estimated GFR rates <30 mL/min/1.73 m². For more information, please see the ACR Manual on Contrast Media (see the "Availability of Companion Documents" field).

Abbreviations

• CT, computed tomography
• CTA, computed tomography angiography
• FDG-PET, fluorine-18-2-fluoro-2-deoxy-D-glucose positron emission tomography
• Med, medium
• MRA, magnetic resonance angiography
• MRI, magnetic resonance imaging
• US, ultrasound

Algorithms were not developed from criteria guidelines.

The recommendations are based on analysis of the current literature and expert panel consensus.

Selection of appropriate radiologic imaging procedures for evaluation of patients with neck mass/adenopathy

The American College of Radiology (ACR) Committee on Appropriateness Criteria and its expert panels have developed criteria for determining appropriate imaging examinations for diagnosis and treatment of specified medical condition(s). These criteria are intended to guide radiologists, radiation oncologists, and referring physicians in making decisions regarding radiologic imaging and treatment. Generally, the complexity and severity of a patient's clinical condition should dictate the selection of appropriate imaging procedures or treatments. Only those exams generally used for evaluation of the patient's condition are ranked. Other imaging studies necessary to evaluate other co-existent diseases or other medical consequences of this condition are not considered in this document. The availability of equipment or personnel may influence the selection of appropriate imaging procedures or treatments. Imaging techniques classified as investigational by the U.S. Food and Drug Administration (FDA) have not been considered in developing these criteria; however, study of new equipment and applications should be encouraged. The ultimate decision regarding the appropriateness of any specific radiologic examination or treatment must be made by the referring physician and radiologist in light of all the circumstances presented in an individual examination.

An implementation strategy was not provided.

Not applicable: The guideline was not adapted from another source.

The American College of Radiology (ACR) provided the funding and the resources for these ACR Appropriateness Criteria®.

Committee on Appropriateness Criteria, Expert Panel on Neurologic Imaging

Panel Members: Suresh Kumar Mukherji, MD (Principal Author); Franz J. Wippold II, MD (Panel Chair); Rebecca S. Cornelius, MD (Panel Vice-Chair); James A. Brunberg, MD; Patricia C. Davis, MD; Robert L. De La Paz, MD; Pr. Didier Dormont; Linda Gray, MD; John E. Jordan, MD; Brian Nussenbaum, MD; David J. Seidenwurm, MD; Michael A. Sloan, MD, MS; Patrick A. Turski, MD; Robert D. Zimmerman, MD; Brian D. Coley, MD

Not stated

Note: This guideline has been updated. The National Guideline Clearinghouse (NGC) is working to update this summary.

Electronic copies of the updated guideline: Available in Portable Document Format (PDF) from the American College of Radiology (ACR) Web site.

Print copies: Available from the American College of Radiology, 1891 Preston White Drive, Reston, VA 20191. Telephone: (703) 648-8900.

The following are available:

• ACR Appropriateness Criteria®. Overview. Reston (VA): American College of Radiology; 2 p. Electronic copies: Available in Portable Document Format (PDF) from the American College of Radiology (ACR) Web site.
• ACR Appropriateness Criteria®. Literature search process. Reston (VA): American College of Radiology; 1 p. Electronic copies: Available in Portable Document Format (PDF) from the ACR Web site.
• ACR Appropriateness Criteria®. Evidence table development. Reston (VA): American College of Radiology; 4 p. Electronic copies: Available in Portable Document Format (PDF) from the ACR Web site.
• ACR Appropriateness Criteria®. Radiation dose assessment introduction. Reston (VA): American College of Radiology; 2 p. Electronic copies: Available in Portable Document Format (PDF) from the ACR Web site.
• ACR Appropriateness Criteria® Manual on contrast media. Reston (VA): American College of Radiology; 90 p. Electronic copies: Available in PDF from the ACR Web site.

None available

This NGC summary was completed by ECRI Institute on May 26, 2010. This summary was updated by ECRI Institute on January 13, 2011 following the U.S. Food and Drug Administration (FDA) advisory on gadolinium-based contrast agents.

Instructions for downloading, use, and reproduction of the American College of Radiology (ACR) Appropriateness Criteria® may be found on the ACR Web site .