稀释胃液固有荧光光谱对胃癌诊断价值的研究

目的 :探讨稀释后胃液固有荧光光谱在胃癌诊断中的应用价值。方法 :胃液稀释后 ,应用RF 5 0 0 0型荧光分光光度计 ,以 2 88nm为激发光 ,测定 30 0～ 80 0nm发射光范围内的荧光光谱。结果 :共测定了 2 5 1例各种胃内良、恶性病变患者 (其中进展期胃癌 39例 ,重度异型增生 1例 )的稀释胃液固有荧光光谱 ,发现原有胃液固有荧光光谱有 3个峰 ,稀释后胃液固有荧光光谱的峰位和峰数不变 ,仅相对荧光强度指数 (FI)改变。胃癌患者稀释胃液 (体积比 1∶2 0 )固有荧光光谱的峰位和峰数与胃内良性病变患者基本相同 ,仅第 1峰 (位于 32 0～ 36 0nm处 )的相对荧光强度指数 (P1FI)增大。用CARTV2 .0软件进行分析 ,以P1FI >38.995为胃癌诊断标准 ,用于诊断胃癌的先验概率的敏感度为 85 .0 % ,特异度为 91.9% ;后验概率的敏感度为 82 .5 % ,特异度为 91.9%。如以P1FI >2 4 .34作为胃癌阳性判定标准 ,则诊断胃癌的敏感度为 95 .0 % ,特异度为 75 .8%。结论 :稀释后的胃液固有荧光光谱可能成为有效的胃癌临床诊断及筛查手段

Study of autofluorescence spectrum of dilute gastric juice in the diagnosis of gastric carcinoma

OBJECTIVE: To investigate the value of the autofluorescence spectrum of dilute gastric juice in the diagnosis of gastric carcinoma. METHODS: The autofluorescence spectrum of dilute gastric juice was scanned with RF-5000 spectrophotofluorometer when the excitation wavelength was set to 288 nm and the emission wavelength ranged from 300 nm to 800 nm. RESULTS: We enrolled 251 patients with different gastric diseases including 40 cases with gastric carcinoma in our study. There were three characteristic peaks in the autofluorescence spectrum of gastric juice, which appeared in the spectra of both dilute and indilute specimens, but relative fluorescence intensity index (FI) of the peaks changed with concentration. The spectra of dilute gastric juice (1:20) of both benign and malignant gastric diseases had those three peaks. However, the fluorescence intensity index of the first peak (P1FI) at 320-360 nm of patients with gastric carcinoma was higher than that of patients with benign gastric diseases. The diagnosis model for gastric carcinoma was made by CART V2.0 software. The diagnosis standard for gastric carcinoma was P1FI > 38.995. The model's sensitivity and specificity of prior probability were 85.0% and 91.9% respectively. The sensitivity and specificity of posterior probability were 82.5% and 91.9% respectively. When the diagnosis standard was set to P1FI > 24.34, the sensitivity and specificity were 95.0% and 75.8%, respectively. CONCLUSION: The autofluorescence spectrum of dilute gastric juice may become an effective means in the diagnosis and screening of gastric carcinoma.