Relationship Between¹⁸F-FDG Uptake And Clinically Relevant Factors, Ki-67and TTF-1in Non-small Cell Lung Cancer

Background and objectivelung cancer is the leading mortality in all kinds of malignant tumour. PET/CT,Ki-67, TTF-1has important application value in terms of lung cancer, while thestandard uptake value (SUV) is a semi-quantitative index of PET/CT. This studymainly investigates the relationship between primary tumor maximum standarduptake value (SUVmax) in non-small lung cancer associated with clinical factors andthe expression of Ki-67, TTF-1.Materials and MethodsClinical data about71cases of identified pathologically non-small cell lungcancer (NSCLC) were collected from January,2011to January,2014.71casesunderwent18F-FDG PET/CT imaging two weeks before the operation. SP stainingwas used in immunohistochemical. The expression of Ki-67and TTF-1was record.Selected objects were untreated NSCLC patients without other history ofmalignancy.Use SPSS17.0software for statistical analysis. Single factor analysis ofvariance is used to compare with SUVmaxvalues between different pathologicaltypes. Using independent samples t test to analysis the differences of SUVmaxbetween primary tumor maximum level of length to diameter, with or without hilaror mediastinal lymph node metastasis and the expression of TTF-1. The impact ofpathological type, with or without lymph node metastasis and Ki-67, TTF-1onSUVmaxis analyzed by multiple linear regression analysis. The correlation ofSUVmaxwith Ki-67is analyzed by Pearson analysis method. Test level α=0.05. Results1. Comparison of SUVmaxbetween different clinical factors in NSCLCIn71patients with NSCLC underwent18F-FDG PET/CT imaging, SUVmaxvalue ranges from3.4to30.4with an average of12.2±6.1, primary foci maximumlevel of length to diameter was1.1to11.1cm, the average is4.1±2.1cm. To bebounded by3cm, the maximum level of length to diameter is divided into≦3cmand>3cm two groups. There were47cases of adenocarcinoma,14cases ofsquamous cell carcinoma and10cases of other types (three cases ofadeno-squamous, four cases of large cell carcinoma and three cases of sarcomatoidcarcinoma). There were48men and23women aged42-78years with an average61.6±5.2years old. Pathologically confirmed hilar or mediastinal lymph nodemetastasis in37cases, no hilar or mediastinal lymph node metastasis in34cases.TTF-1was positive in49cases,22cases of TTF-1negative group.SUVmaxof different pathological type was analyzed by ANOVA, and the resultsshowed that the difference of SUVmaxin adenocarcinoma, squamous carcinoma andother types was statistically significant (F=7.162, P<0.01). The difference of SUVmaxin adenocarcinoma and squamous cell carcinoma,adenocarcinoma and other types ofNSCLC was statistically significant by LSD-t test for pairwise comparison(P<0.05),while SUVmax in squamous carcinoma and other types had no statistical difference(P>0.05).SUVmaxdifference of primary tumor maximum diameter, with or without hilarand mediastinal lymph node metastasis was analyzed by independent samples t-testanalysis, and the results showed: SUVmaxdifference of primary tumor maximumlevel of length to diameter≦3cm and>3cm was not statistically significant (P>0.05); SUVmaxvalue with hilar or mediastinal lymph node metastasis wassignificantly higher than SUVmaxvalue without hilar and mediastinal lymph nodemetastasis, and the difference was statistically significant (t=-6.719, P<0.05).Using multiple linear regression analysis to explore the relationship betweenprimary focal SUVmaxvalue and Ki-67, TTF-1, pathological classification, themaximum level of primary focal length to diameter, with or without hilar ormediastinal lymph node metastasis, the stepwise regression method is adopted to filter variables, the results show that there is a linear regression relationship betweenSUVmaxand lymph node metastasis, pathological types(P <0.05), while there is nolinear relationship between SUVmaxand Ki-67, TTF-1, primary focal length todiameter(P>0.05). Hilar or mediastinal lymph node metastasis and pathologicalclassification are independent of the influence factors of the primary focal SUVmax(F=26.384, P<0.05). As can be seen from the standardized partial regressioncoefficient, hilar or mediastinal lymph node metastasis affect primary focal SUVmaxvalues more.2. Comparison of SUVmaxbetween the expression of different TTF-1levels inNSCLC primary focusUsing independent samples t test to compare of SUVmaxin non small cell lungcancer primary foci between TTF-1negative group and positive group, the resultshows that SUVmaxof TTF-1negative group was significantly higher than that ofTTF-1positive group, and the difference was statistically significant (t=2.193,P<0.05).3. Correlation analysis of SUVmaxand Ki-67in NSCLC primary focusExplore the relationship between SUVmaxvalue of NSCLC primary tumor andKi-67by Pearson correlation analysis method, and the results show that SUVmaxandKi-67have a positive correlation(r=0.308, P<0.05).Conclusion1. SUVmaxvalue of NSCLC primary foci had no relationship with maximumlevel of length to diameter, while it had relationship with pathological type、with orwithout hilar and mediastinal lymph node metastasis. NSCLC primary focus SUVmaxvalue of squamous was higher than that of adenocarcinoma. Patients with highSUVmaxvalue are more likely to happen hilar or mediastinal lymph node metastasis，which is helpful to judge the prognosis and provide individualized treatment.Multiple linear regression analysis showed, hilar or mediastinal lymph nodemetastasis condition and pathological types are independent risk factors of SUVmaxvalue. Hilar or mediastinal lymph node metastasis condition affects SUVmaxmore.2. SUVmaxof NSCLC primary foci in TTF-1-negative group is significantlyhigher than that of TTF-1positive group, which suggests that SUVmaxof NSCLC primary focus in TTF-1negative group is relatively higher than that of positivegroup, TTF-1negative group has higher cell metabolism and higher tumor activity.3. SUVmaxvalue of NSCLC primary focus had a positive correlation with Ki-67,which indicats that the higher SUVmaxvalue of primary tumor,the higher expressionlevel of Ki-67, SUVmaxcan indirectly reflect the tumor cell proliferation.