評估免疫法糞便潛血篩檢與血液指標之相關性

Evaluation of iFOB Screening Test and the Correlations with Hematological Parameters

在台灣地區，大腸直腸癌位居所有癌症發生率的第二名、癌症相關死亡率的第三名。篩檢糞便潛血(fecal occult blood, FOB)有助於早期發現大腸癌病變並早期進行治有效療。本研究是收集成大醫院病理部進行糞便潛血篩檢30歲以上之病患，探討以免疫法測定FOB(immuno FOB, iFOB)與全套血液計數(complete blood count, CBC評估紅血球、白血球及血小板三系列)、年齡、性別以及大腸鏡(分為5類：無異常、痔瘡、瘜肉、痔瘡合併瘜肉、其他)結果的相關性。分析結果發現，大於40歲齡iFOB陽性與大腸鏡檢查結果陽性相關(p=0.004)，大於50齡之iFOB陽性率較小於50歲齡者為高(p<0.001)。另外，iFOB陽性者之紅血球數、血紅素濃度、血比容較低，平均血球容積與紅血球體積分佈寬度則較大(p<0.05)。依性別分析，女性iFOB陽性者與紅血球數、血紅素濃度、血比容及紅血球體積分佈寬度仍舊顯著相關，且與大球型居多紅血球(p<0.05)；而在男性iFOB陽性者之相關則無顯著性。由結果得知，免疫法糞便潛血檢查與紅血球指標確實有相關性，建議可將其結合應用納入大腸直腸癌篩檢策略與進一步治療預後評估，iFOB陽性者在追蹤時，可留意CBC之異常變化。

In Taiwan local area, the colorectal cancer represents the second leading malignancy and the third cancer-related mortality. Fecal occult blood (FOB) screening helps for the early diagnosis of colorectal cancer thus facilitates therapeutic intervention as efficient as possible. In this study, the patient recruitment included those who aged over 30 yrs and undertook FOB screening in the Department of Pathology, National Cheng Kung University Hospital. The correlations were under investigation between immuno FOB (iFOB) analysis and complete blood count (CBC, evaluation for the 3 lineages including red blood cells, white blood cells and platelets) analysis, age, gender and examination of colonoscopy (evaluation for the 5 conditions including no finding, hemorrhoid, polyps, combined hemorrhoid and polyps and others). The current results revealed that the iFOB positivity was correlated with the findings with colonoscopic examination in the patients aged over 40 yrs (p-value=0.004). The positive rate of iFOB was higher in the patients aged over 50 yrs than those less than 50 yrs (p-value<0.001). Additionally, the patients with iFOB positivity had lower levels of red blood cell count (RBC), hemoglobin (Hb) concentration and hematocrit (Hct) value, but higher levels of mean capsule volume (MCV) and red blood cell distribution width (RDW) (p-values<0.05). As the patients were stratified by gender, the females still showed iFOB positivity in correlation with red blood cell count, hematocrit, red blood cell distribution width and macrocytosis. However, the correlations were not significant in males. In conclusion, our results suggested the associations between FOB testing and red blood cell index, which should be considered in the screening strategy and further prognosis and treatment of colorectal cancer. It is suggested that CBC abnormality should be considered in the follow-up of iFOB positive patients.