Description
High resolution CT can visualize both normal and pathologic anatomy of the neck. It is used in the evaluation of neck soft tissue masses, abscesses, and lymphadenopathy. For neck tumors, it defines the extent of the primary tumor and identifies lymph node spread. CT provides details about the larynx and cervical trachea and its pathology. Additional information regarding airway pathology is provided by three-dimensional images created from the CT dataset. Neck CT can also accurately depict and characterize tracheal stenoses.

With the rise of human papillomavirus-related oral, pharyngeal, and laryngeal cancers in adults, contrast-enhanced neck CT has become more important for the evaluation of a neck mass, deemed at risk for malignancy, surpassing ultrasound for the initial evaluation in many cases.

The American Academy of Otolaryngology — Head and Neck Surgery recently issued strong recommendations for neck CT or MRI, emphasizing the importance of a timely diagnosis.⁵

GENERAL INFORMATION

It is an expectation that all patients receive care/services from a licensed clinician. All appropriate supporting documentation, including recent pertinent office visit notes, laboratory data, and results of any special testing must be provided. If applicable: All prior relevant imaging results and the reason that alternative imaging cannot be performed must be included in the documentation submitted.

Where a specific clinical indication is not directly addressed in this guideline, medical necessity determination will be made based on widely accepted standard of care criteria. These criteria are supported by evidence-based or peer-reviewed sources such as medical literature, societal guidelines and state/national recommendations.

Policy

INDICATIONS
Suspected Tumor or Cancer

• Suspicious lesions in mouth or throat¹
• Suspicious tumor or cancer mass/tumor found on another imaging study and needing clarification²

Neck Mass or Lymphadenopathy (not parotid or thyroid region)

• • Mass present 2: two weeks (or uncertain duration) without significant fluctuation and not considered of infectious cause
• • History of cancer
• Failed 2 weeks of treatment for suspected infectious adenopathy^3,4
• Pediatric (5 – 18 years old) considerations⁵
  • Ultrasound should be inconclusive or suspicious unless there is a history of malignancy⁶

Note: For discrete cystic lesions of the neck, an ultrasound should be performed as initial imaging unless there is a high suspicion of malignancy

Neck Mass (parotid region)

• Parotid mass found on other imaging study and needing further evaluation

Note: US is the initial imaging study of a parotid region mass to determine if the location is inside or outside the gland^2,7

Neck Mass (thyroid region)

• Staging and monitoring for recurrence of known thyroid cancer⁸
• To assess extent of thyroid tissue when other imaging suggests extension through the thoracic inlet into the mediastinum or concern for airway compression⁹

Note: US is the initial imaging study of a thyroid region mass. Biopsy is usually the next step. In the evaluation of known thyroid malignancy, CT is preferred over MRI since there is less respiratory motion artifact. Chest CT may be included for preoperative assessment in some cases.

Follow-up of Known Tumor or Cancer¹⁰
For malignancies not listed, Neck CT is only indicated when there are signs or symptoms of neck involvement (such as palpable masses/lymph nodes or dysphagia)

Initial Staging

• • B cell lymphomas (follicular lymphoma, diffuse large B cell lymphoma, Burkitt lymphoma, B-lymphoblastic lymphoma, post-transplant lymphoproliferative disorders)
  • ALL
  • AML
  • Hodgkin lymphoma (pediatric and adult)
  • Pediatric aggressive mature B cell lymphomas (Burkitt lymphoma, Diffuse large B cell lymphoma, primary mediastinal large B cell lymphoma)
  • Occult primary

Restaging

• Neck CT is indicated during active treatment (every 2 – 3 cycles of chemotherapy or immunotherapy, following radiation and/or after surgery) for the following malignancies:
  • Head and neck cancers (and after radiation treatment)
  • Thyroid cancer (and after surgery and/or if any concern for recurrence or progression)
  • ALL
  • AML
  • B Cell lymphomas (follicular lymphoma, diffuse large B cell lymphoma, Burkitt lymphoma, B-lymphoblastic lymphoma, post-transplant lymphoproliferative disorders)
  • Hodgkin lymphoma (pediatric and adult)
  • Pediatric aggressive mature B cell lymphomas (Burkitt lymphoma, Diffuse large B cell lymphoma, primary mediastinal large B cell lymphoma)
  • Occult primary

Surveillance

• • Head and Neck cancer annually when specified that the area of original disease is difficult to follow on direct visualization (surveillance is typically with exam/scope rather than imaging)
  • Hodgkin lymphoma (pediatric and adult) every 3 – 6 months for 2 years
  • Occult primary every 3 – 6 months for 2 years, every 6 – 12 months for 3 years, then annually

Note: There would need to be a sign or symptom of recurrence to consider Neck CT when the time frame above for routine surveillance has elapsed OR when a cancer is not listed above because neck CT is not routinely a part of surveillance for that cancer in an asymptomatic patient.

Other Indications

• Bell’s palsy/hemifacial spasm, if MRI is contraindicated or cannot be performed (for evaluation of the extracranial nerve course)
  • If atypical signs, slow resolution beyond three weeks, no improvement at four months, or facial twitching/spasms prior to onset²²
• Objective cranial nerve palsy (CN IX – XII) if MRI is contraindicated or cannot be performed (for evaluation of the extracranial nerve course)²²

Preoperative/Procedural Evaluation

• Pre-operative evaluation for a planned surgery or procedure

Postoperative/Procedural Evaluation

• A follow-up study may be needed to help evaluate a patient’s progress after treatment, procedure, intervention, or surgery. Documentation requires a medical reason that clearly indicates why additional imaging is needed for the type and area(s) requested.

Combination Studies
Neck/Chest CT

• Vocal cord paralysis on endoscopic exam and concern for recurrent laryngeal nerve lesion
• Phrenic nerve paralysis on diaphragm fluoroscopy (fluoroscopic sniff test)

Neck/Face CT or MRI and PET

• Neck/Face CT or MRI is indicated in addition to PET for Head and Neck Cancer
  • For surgical or radiation planning
  • 3-4 months after end of treatment in patients with locoregionally advanced disease or with altered anatomy

Combination Studies for Malignancy for Initial Staging or Restaging
Unless otherwise specified in this guideline, indication for combination studies for malignancy for initial staging or restaging:

• Concurrent studies to include CT or MRI of any of the following areas as appropriate depending on the cancer: Abdomen, Brain, Chest, Neck, Pelvis, Cervical Spine, Thoracic Spine or Lumbar Spine.

Further Evaluation of Indeterminate Findings on Prior Imaging
Unless follow-up is specified elsewhere in the guideline:

• For initial evaluation of an inconclusive finding on a prior imaging report that requires further clarification
• One follow-up exam of a prior indeterminate MR/CT finding to ensure no suspicious interval change has occurred. (No further surveillance unless specified as highly suspicious or change was found on last follow-up exam)

Contraindications and Preferred Studies

• Contraindications and reasons why a CT/CTA cannot be performed may include: impaired renal function, significant allergy to IV contrast, pregnancy (depending on trimester).
• Contraindications and reasons why an MRI/MRA cannot be performed may include: impaired renal function, claustrophobia, non-MRI compatible devices (such as non- compatible defibrillator or pacemaker), metallic fragments in a high-risk location, patient exceeds limit/dimensions of MRI machine.

Rationale
CT can define the extent of the primary neck tumor and identify lymph node spread. With the rise of human papillomavirus-related oral, pharyngeal, and laryngeal cancers in adults, contrast-enhanced neck CT has become more important for the evaluation of a neck mass, deemed at risk for malignancy, surpassing ultrasound for the initial evaluation in many cases. The American Academy of Otolaryngology-Head and Neck Surgery recently issued strong recommendations for neck CT or MRI, emphasizing the importance of a timely diagnosis.³

References 

19. Shephard E, Parkinson M, Hamilton W. Recognising laryngeal cancer in primary care: a large case-control study using electronic records. Br J Gen Pract. Feb 2019; 69: e127-e133. 10.3399/bjgp19X700997.
20. Earwood J, Rogers T, Rathjen N. Ear Pain: Diagnosing Common and Uncommon Causes. Am Fam Physician. Jan 1, 2018; 97: 20-27.
21. Zander D, Bunch P, Policeni B, Juliano A, Carneiro-Pla D et al. ACR Appropriateness Criteria: Parathyroid Adenoma. Journal of the American College of Radiology. 2021; 18: S406 - S422. 10.1016/j.jacr.2021.08.013.
22. American College of Radiology. ACR Appropriateness Criteria® Cranial Neuropathy. 2022; 2023:

Coding Section 

Procedure and diagnosis codes on Medical Policy documents are included only as a general reference tool for each policy. They may not be all-inclusive. 

This medical policy was developed through consideration of peer-reviewed medical literature generally recognized by the relevant medical community, U.S. FDA approval status, nationally accepted standards of medical practice and accepted standards of medical practice in this community, and other nonaffiliated technology evaluation centers, reference to federal regulations, other plan medical policies, and accredited national guidelines.

"Current Procedural Terminology © American Medical Association. All Rights Reserved" 

History From 2019 Forward