ABSTRACT
Objective To study the methods of matching kilovolt CBCT image with planning CT scan. Methods A total of 121 CBCT scans were matched with planning CT scan using a manual and four automatic match methods by four observers in the offline. In the manual match, the live contour was used as a surrogate for image registration. Four automatic match methods, including routine soft?tissue match, routine bone match, automatic liver match and vertebral body match, were performed using image registration sofeware. First, the stability of the sofeware was tested. Then, the reproducibility of the same automatic match method was evaluated by comparing different observers’ match results. After the manual match by four observers, the mean of the match results was used as a standard to compare with others. The differerces was test by McNemar method. Results In the uniform match factors, automatic match result would not change. The reproducibility of routine soft?tissue and bone match are best, automatic vertebral body match is better than automatic liver match. Howerver, the automatic liver match result is the most similar to manual match, the percentages of match result have an absolute error no more than 3 mm in left?right, superior?inferior and anterior?posterior directions are 84?? 3%, 77?? 7% and 92?? 6%. Conclusions Automatic liver match can be used in image?guided radiotherapy for liver cancer, however, it should be performed by experienced oncologist and technologist together in each fraction, after that, the matching result should be adjusted carefully according to live contour.
ABSTRACT
Objective To evaluate the expression of peroxisome proliferator-activated receptor γ(PPARγ)and retinoid x receptorα(RXRα)in cholangiocarcinoma to explore its relation to clinicopathological factors and investigate its impact on prognosis.Methods Expression of PPARγ and RXRα was detected by immunohistochemistry in 69 cases of cholangiocarcinoma and 12 non-tumor cases.The relation of PPARγ and RXRα expression to clinicopathological parameters and prognosis was determined.Results The expression rates of PPARγ in 69 cases of cholangiocarcinoma and 12 non-tumor cases were 59.4% and 0, respectively(P＜0.05).The expression rates of RXRα in 69 cases of cholangiocarcinoma and 12 non-tumor cases were 78.3% and 20%, respectively.There were significant differences between the 2 groups in PPARγ and RXRα expression.PPARγ expression was associated with TNM clinical stages and lymph node metastasis.According to univariate survival analysis,PPARγ expression was correlated with poor prognosis(P＜0.05).There was positive correlation between PPARγ and RXRα.Conclusion The expression of PPARγis significantly correlated with the clinicopathological characteristics and biological behaviors of cholangiocarcinoma.PPARγ and RXRα expression may play an important role during tumorigenesis.
ABSTRACT
Objective To investigate the relationship between expression of P-glycoprotein (P-gp), glutathione S-transferase-π (GST-π) and chemosensitivities in lymph node metastases (LNMs) of gastrointestinal carcinomas. Methods Tumor chemosesitivities to 9 drugs was measured by MTT assay, and the expression of P-gp and GST-π were determined immunohistochemically in primary tumor (PT) and LNMs of gastrointestinal carcinomas in 54 patients. Results The P-gp expression was detected in 22% cases (k= -0.0133, P =0.8698) for beth PT and LNMs, and of GST-π in 50% (k =0. 1137, P= 0. 1496). Expression of P-gp and GST-π in LNMs were stronger eompared with PT (Z = -3. 0448, Z = -2. 1178, both P <0. 05). The inhibition rates of LNMs cells for VCR, OPT, OXA, DDP and MTX were lower than those to PT (all P < 0. 05), but for VP-16 it was higher (P < 0. 05). In PT, there were negative correlation between expression of P-gp and inhibition rates of tumor cells for 5-FU, VCR and PTX respectively (r = -0. 4142 ～ -0. 5712, all P <0. 05), and GST-π for 5-FU, VCR, OPT and PTX as well (r = -0. 3927 ～ -0. 4951, all P <0. 05). In LNMs, negative correlation between expression of P-gp and inhibition rates of tumor cells for VP-16, PTX and eADM were found statistically (r = - 0. 3802 ～ - 0. 4624, all P < 0. 05), and also GST-π for 5-FU, VCR and DDP (r = - 0. 3996 ～ - 0. 5345, all P < 0. 05). Conclusions The LNMs of gastrointestinal carcinomas are heterogeneous with respect to expression of mdr-related factors and response to chemotherapy, and more resistant than the PT for chemotherapeutants. Effective adjuvant chemotherapy in gastrointestinal cancers depends on targeting the metastatic component of the tumor.