Neck neoplasms: MR imaging. Part II. Posttreatment evaluation.

Area of Science:

• Radiology
• Oncology
• Medical Imaging

Background:

• Neck cancer treatment often involves surgery and radiation therapy.
• Post-treatment changes like fibrosis and scarring can complicate imaging interpretation.
• Accurate assessment of tumor recurrence and anatomical structures is crucial for patient management.

Purpose of the Study:

• To compare the utility of magnetic resonance (MR) imaging and computed tomography (CT) in evaluating patients with malignant neoplasms of the neck after treatment.
• To assess the ability of MR imaging to differentiate between post-treatment changes and recurrent tumor.
• To determine the strengths and limitations of MR imaging and CT in this patient population.

Main Methods:

• Retrospective analysis of 33 patients with prior neck cancer treatment (surgery and/or radiation).
• MR imaging was performed on all 33 patients; CT was performed on 27.
• Patients included healthy volunteers (10) and those with documented tumor recurrence (23).

Main Results:

• MR imaging demonstrated normal muscular landmarks better than CT, particularly with obliterated fat planes.
• Post-treatment fibrosis/scarring appeared as low signal intensity on MR images.
• MR imaging was superior to CT in defining tumor-muscle relationships and vascular anatomy (without contrast).
• CT better visualized adjacent bone and cartilage anatomy.
• In three patients, postradiation edema mimicked neoplasm on MR imaging due to high signal intensity.

Conclusions:

• MR imaging is valuable for evaluating neck cancer patients post-treatment, especially when CT findings are indeterminate.
• MR imaging excels at differentiating recurrent tumors from fibrosis and assessing soft tissue structures.
• CT remains superior for evaluating bony and cartilaginous structures in the neck.