The choline/creatine ratio in five benign neoplasms: Comparison with squamous cell carcinoma by use of in vitro MR spectroscopy

BACKGROUND AND PURPOSE: The choline (Cho)/creatine (Cr) ratio has been show n to be a reliable proton MR spectroscopy metabolic marker for differentiat ing squamous cell carcinoma (SCCA) from normal muscle in the upper aerodige stive tract. However, it is unclear whether the Cho/Cr ratio can be used to differentiate a malignant tumor from a benign neoplasm in the extracranial head and neck. Our purpose was to determine whether the Cho/Cr ratio can b e used to differentiate benign from malignant tumors in this region. : METHODS: In vitro one-dimensional proton MR spectroscopy (2000/136,272 [TR/ TE]) was performed at 11 T on tissue specimens obtained from glomus tumors (n = 3), inverting papilloma (n = 1), and schwannoma (n = 1), Cho/Cr area r atios were calculated and compared with similar, previously reported in vit ro (11 T) findings and with samples of SCCA and normal muscle, RESULTS: The Cho/Cr ratio as elevated in relation to muscle in all benign t umors at TE = 136 (glomus tumors = 4.52, inverting papilloma = 3.85, schwan noma = 2.2) and at TE = 272 (glomus tumors = 8.01, inverting papilloma = 2. 1, schwannoma = 4.28), The average Cho/Cr ratio for benign lesions was 3.92 (TE = 136) and 6.11 (TE = 272), The Cho/Cr ratio was Significantly higher in benign tumors than in both SCCA and muscle. The average Cho/Cr ratio for muscle at TEs of 136 and 272 was 1.16 and 1.31, respectively, whereas for SCCA the average Cho/Cr ratio at TEs of 136 and 272 was 1.67 and 2.45, resp ectively. CONCLUSION: In our small group, the Cho/Cr ratio was significantly higher i n benign tumors than in muscle and SCCA of the extracranial head and neck.