Laryngeal carcinoma after radiation therapy: Correlation of abnormal MR imaging signal patterns in laryngeal cartilage with the risk of recurrence

PURPOSE: To correlate abnormal magnetic resonance (MR) imaging signal patterns in cartilage with the effectiveness of radiation treatment. MATERIALS AND METHODS: Eighty previously untreated patients underwent MR imaging and radiation therapy with a curative intent. Cartilage was considered to have an abnormal signal pattern if it had intermediate signal intensity on TI-weighted spin-echo (SE) MR images and high signal intensity on T2-weighted SE MR images. The minimum follow-up was 2 years. RESULTS: Abnormal MR imaging signal patterns of the thyroid cartilage (P < .001; P < .04) were more ominous than those of other cartilage. Abnormal signal patterns in cartilage of patients with small tumors (<5 cm(3) and especially <1 cm(3)) were less significant. Abnormal signal patterns in cartilage combined with a large tumor (>5 cm(3)) worsened the prognosis significantly (P < .05). CONCLUSION: Abnormal MR imaging signal patterns in cartilage may not indicate a poor prognosis in every ease. Abnormal signal intensity in the thyroid cartilage combined with a tumor volume of >5 cm(3), however, appears to indicate an adverse prognosis with regard to tumor recurrence.