評估磁共振光譜在乳癌診斷的臨床應用

Evaluation of the Clinical Application of Magnetic Resonance Spectroscopy in the Diagnosis of Breast Cancer

目的：運用磁共振光譜技術(magnetic resonance spectroscopy; MRS)對疑似乳腺病變患者的代謝物予以光譜信號分析，評估加入光譜技術的輔助後是否能更提高磁振影像對於乳癌的診斷正確率，進而早期發現早期治療，達到癌症防治效果。方法：從本研究執行乳房磁振造影案例中，給予常規藥物(Dotarem)後，選出大於或等於1公分以上的顯影疑似病灶，進行動態顯影之動力曲線分析(kinetic curve analysis；KC)及MRS分析，共40個案例數，最後再與病理結果比較(採用Excel 2013及SPSS 17分析數據)。結果：依據過去的文獻表明，當KC為型態三和MRS為陽性皆是惡性之表徵。於40個案例中，病理結果惡性有38個；23個呈現型態三，敏感性為60.5%，特異性為50%，獨立卡方檢定(χ2)為0.526，p值為0.769；30個光譜呈陽性，敏感性、特異性各為78.9%、50%，χ2為0.913，p值為0.034；整體來說，MRS的診斷效益比KC較佳，但兩者與病理結果之關聯性弱，結果沒有顯著差異。最後，再利用公式將兩者特異性結合得總特異性為75%，提升了MRI的特異性。結論：研究結果未達顯著意義，經探討原因發現於收案期間臨床更改患者治療追蹤檢查流程，與本研究原本預期的檢查流程不同，是以病理惡性檢出率高於特異性；敏感性也因個案多是確診患者，導致敏感性偏低；本研究結果雖與預期結果有誤差，但仍有其參考價值，對於之後研究，或許可從另外角度探討其可行性。

Objectives. The incidence of breast cancer continues to rise and it continues to be a major threat of women's health. Thus, breast screening is an urgent and important issue. In this study, we used metabolite spectrum signal MRS (magnetic resonance spectroscopy) to screen for suspected breast lesions and assessed whether adding auxiliary MRI in suspected cases of breast cancer could help improve early diagnosis.
Methods. A total of 40 cases with suspected lesions≧1cm received breast MRI with CM (Dotarem) at our hospital. Diagnosis was based on dynamic enhanced KC (kinetic curve) following conventional protocol, MRS, and pathological findings.
Results. The collected data from these 40 cases were analyzed. A type three KC and a positive MRS were assumed to indicate malignant lesion. Of the 40 cases, 38 were had pathology proved malignancies. There were 23 cases with type three KC (sensitivity 60.5%, specificity 50%) (p=0.769) (Independent chi-square test (χ2) is 0.526). Thirty with positive MRS were found to have malignancies, with a sensitivity and specificity of 78.9% and 50%, respectively (χ2 of 0.913; p=0.034). Overall, the diagnostic benefit of MRS was better than KC, though the correlation between pathology between the two was weak, with results not being significantly different. Using a formula to combine KC and MRS data, we were able to diagnose malignancies with a total specificity of 75%, and increase the specificity of MRI.
Conclusion. Regardless, the results reviewed non-significant, possibly because clinical follow-up inspection process during the case collection period was changed and different from the original inspection process originally planned for this study. Therefore, the detection rate of pathology proven malignancies was higher than the specificity. Another problem was most cases were diagnosed patients, resulting in low sensitivity.