PROTON MR SPECTROSCOPY OF SQUAMOUS-CELL CARCINOMA OF THE UPPER AERODIGESTIVE TRACT - IN-VITRO CHARACTERISTICS

PURPOSE: To determine the ability of in vitro high-field-strength prot on MR spectroscopy to differentiate squamous cell carcinoma of the upp er aerodigestive tract from uninvolved muscle. METHODS: Surgical speci mens of squamous cell carcinoma arising from the upper aerodigestive t ract (n = 18) and from muscle (n = 13) were examined in vitro using hi gh-field (11 T) proton MR spectroscopy. The peak heights of choline an d creatine were measured for tumor and muscle at echo times of 136 and 272. The choline/creatine (Cho/Cr) ratio was compared between tumor a nd normal tissue for each echo time. Student's t test was used to dete rmine whether a significant difference existed between proton MR spect roscopic measurements of the Cho/Cr ratio for tumor and muscle. RESULT S: The mean Cho/Cr ratio was consistently higher in tumor than in musc le at all echo times; however, statistically significant differences b etween tumor and muscle were identified only at longer echo times (136 and 272). CONCLUSION: The Cho/Cr peak height ratio can be used to dif ferentiate tumor from muscle in vitro (at 11 T).