A preliminary study of apparent diffusion coefficient in chemotherapy-induced liver damage.

OBJECTIVES: To investigate changes in the hepatic apparent diffusion coefficient (ADC) in patients undergoing chemotherapy. METHODS: We enrolled 54 patients (25 women; mean age 57.0±13.1 years, range 29-89 years) undergoing chemotherapy for tumor and 10 controls (7 women; mean age 55.1±17.5 years, range 23-81 years). The patients were tested for serum alanine aminotransferase (ALT) activity (abnormal, normal) and fatty liver. Hepatic ADC values were compared among controls, patients and subgroups. Pearson correlation coefficient was used to assess the correlation between ADC and ALT activity. RESULTS: Hepatic ADC0,850 (×10(-3) mm2/s) was lower for patients than controls (1.14±0.18 vs. 1.28±0.12, P=0.02) and was lower for patients with than without fatty liver and controls (1.01±0.06 vs. 1.18±0.18 and 1.28±0.12, respectively, all P<0.01), with no significant difference between patients without fatty liver and controls (P=0.07). ADC0,850 was lower for patients with abnormal ALT than normal ALT activity and controls (0.99±0.06 vs. 1.17±0.18 and 1.28±0.12, respectively, all P<0.05), with a significant difference also being seen between patients with normal ALT activity and controls (P=0.04). Hepatic ADC0,850 was not correlated with ALT activity in patients (r=-0.24, P=0.08). CONCLUSIONS: Although ADC did not correlate with ALT values, it did distinguish patient likely to have chemotherapy-induced liver damage as indicated by abnormal ALT values or fatty liver. These mechanisms need to be disentangled.

Perfusion CT findings in liver of patients with tumor during chemotherapy.

AIM: To investigate the microcirculation changes in liver of patients with tumor during chemotherapy by perfusion computed tomography (CT). METHODS: Sixty patients with tumor and 20 controls were enrolled in this study. Perfusion CT parameters of patients and controls were compared, including hepatic perfusion index (HPI), mean transit time (MTT), and permeability-surface area product (PS). Correlation between perfusion CT parameters, treatment cycle and alanine aminotransferase (ALT) level was studied. RESULTS: No difference was found in HPI (25.68% +/- 7.38% vs 26.82% +/- 5.13%), MTT (19.67 +/- 5.68 s vs 21.70 +/- 5.43 s) and PS (17.00 +/- 4.56 mL/100 mL per min vs 19.92 +/- 6.35 mL/100 mL per min) between patients and controls. The HPI and MTT were significantly higher in patients undergoing 2 cycles of chemotherapy than in controls and those undergoing 1 cycle of chemotherapy (29.76% +/- 5.87% vs 25.68% +/- 7.38% and 25.35% +/- 4.05%, and 25.61 +/- 5.01 s vs 19.67 +/- 5.68 s and 19.74 +/- 4.54 s, respectively, P < 0.05). The HPI was higher in patients with hepatic steatosis than in controls and those without hepatic steatosis (30.85% +/- 6.17% vs 25.68% +/- 7.38% and 25.70% +/- 4.24%, P < 0.05). Treatment cycle was well correlated with HPI and MTT (r = 0.40, r = 0.50, P < 0.01). ALT level was not correlated with perfusion CT parameters. CONCLUSION: HPI and MTT are significantly increased in patients with tumor during chemotherapy and well correlated with treatment cycle. Chemotherapy affects hepatic microcirculation in patients with tumor. Changes in hepatic microcirculation can be quantitatively assessed by perfusion CT.

1H-MRSI of prostate cancer: the relationship between metabolite ratio and tumor proliferation.

PURPOSE: To investigate whether 1H-MRSI can be used to predict the proliferative activity of prostate cancer. MATERIALS AND METHODS: Thirty-eight patients with prostate cancer (PCa) and thirty-three patients with benign prostate hyperplasia (BPH) were included in this study. Patients were examined in supine position using a 1.5T superconducting magnetic scanner equipped with a pelvic phased-array multi-coil and CSI-3D-PROSTATE sequence. Commercial software was used to acquire and process MR spectroscopic imaging data. Mean (Cho+Cr)/Cit ratios of PCa, BPH, and peripheral zone (PZ) were calculated. Cellularity of PCa was recorded based on hematoxylin and eosin staining. PCNA was detected using immunohistochemical techniques. RESULTS: The mean (Cho+Cr)/Cit ratio of the peripheral zone (0.38+/-0.09) was lower than that of BPH (0.51+/-0.19) (P<0.05). The average value of (Cho+Cr)/Cit ratio of prostate cancer was 3.98+/-0.12. The (Cho+Cr)/Cit ratio of prostate cancer was higher than that of the peripheral zone and BPH (P<0.05). The cellularity and PCNA LI of prostate cancer were 12.90+/-4.07% and 72.1+/-19.01%, respectively. The (Cho+Cr)/Cit ratio of prostate cancer positively correlated with tumor cellularity (r=0.582, P=0.027) and PCNA LI (r=0.495, P=0.022). CONCLUSION: The (Cho+Cr)/Cit ratio of PCa can reveal the differences in proliferative activity between PCa and BPH. MRSIs are therefore able to predict the proliferative rate of variously differentiated prostate cancers.

Diffusion-weighted imaging of prostate cancer: correlation between apparent diffusion coefficient values and tumor proliferation.

PURPOSE: To investigate whether the apparent diffusion coefficient (ADC) values of prostate cancer (PCa) are able to reflect tumor proliferation. MATERIALS AND METHODS: The clinical and pathological information for 38 patients with PCa and 33 patients with benign prostate hyperplasia (BPH) were studied. Examination of the patients was performed using a 1.5 T superconducting magnetic scanner equipped with a pelvic phased-array multicoil. Diffusion-weighted images (DWIs) were acquired using an echo-planar imaging sequence. The ADC values of PCa, BPH, and peripheral zone (PZ) were calculated. The cellularity of PCa was recorded based on hematoxylin and eosin staining. The proliferating cell nuclear antigen (PCNA) was detected using an immunohistochemical technique. RESULTS: The ADC values of PCa, BPH, and PZ were 49.32 +/- 12.68 x 10(-5) mm(2)/s, 86.73 +/- 26.75 x 10(-5) mm(2)/s, and 126.25 +/- 27.21 x 10(-5) mm(2)/s, respectively. The ADC values of PCa were lower than those of BPH and PZ (P < 0.05). The cellularity and PCNA labeling index (LI) of PCa were higher than those of BPH (P < 0.05). The ADC values of PCa were negatively correlated with those of cellularity and PCNA LI (r = -0.646 and -0.446, respectively; P < 0.05). CONCLUSION: The ADC values of PCa can reveal the differences in proliferative activity between PCa and BPH. These values are therefore able to predict the proliferative rate of variously differentiated prostate cancers.

[Copolymer of 2-hydroxyethyl methacrylate for cerebral arteriovenous malformation: an experimental study].

OBJECTIVE: To investigate the feasibility of using methyl methacrylate (MMA) and 2-hydroxyethyl methacrylate (HEMA) to embolize cerebral arteriovenous malformations (AVM). METHODS: Methyl methacrylate (MMA) and 2-hydroxyethyl methacrylate (HEMA) in the ratio of 9:1 were solved in 16% alcohol so as to make a kind of copolymer (CoHEMA). 12 g glass beads 2 mm in diameter were put into a container so as to construct an in vitro model of AVM. The container was connected with a normal saline bottle via microcatheter. CoHEMA, as embolized, was injected through the microcatheter and the diffusion of CoHEMA was observed till the water flow was stopped. CoHEMA was injected through microcatheter into the pharyngeal ascending arteries near the rete mirabile (RMB) tissue, similar to the human AVM, under digital subtraction angiography until satisfactory embolization was obtained, totally 9 RMB tissues in 7 pigs. Five pigs were injected with normal saline as controls. The pigs were killed 2 days, 2 weeks, and 6 months after embolization respectively and the bilateral RMB tissues were taken out to undergo pathological examination. RESULTS: Nine AVM models in vitro were constructed with the copolymer dispersed symmetrically among the glass beads and stopped the fluid across the model effectively. No copolymer adhered to the wall of microcatheter. Nine RMB tissues of 6 pigs were embolized by using CoHEMA. Six of the seven pigs survived the procedure except one died of too fast injection of copolymer in the primary stage. Follow-up angiography was performed in four pigs and found that no recanalization occurred and the copolymer was diffused in the vessels 80-150 microm in diameter. In the specimens obtained 2 days after embolization, neutrophilic granulocytes scattered surrounding the copolymer, suggesting minor inflammatory reaction. In the specimens obtained 2 weeks after embolization no vessel wall damage and morphological change were found except minor inflammatory reaction inside the vessels and surrounding tissues. In the specimens obtained 2 to 6 months after embolization hyperplasia of connective tissue, minor or mediate chronic inflammatory reaction, and giant cell reaction inside the vessels and surrounding tissues. CONCLUSION: With low viscosity, better biocompatibility, and embolic instability, and easy to be injected through delivery microcatheter, CoHEMA is an excellent non-adhesive embolic material and can be used in embolic treatment of cerebral AVM.

Technical feasibility and histopathologic studies of poly (N-isopropylacrylamide) as a non-adhesive embolic agent in swine rete mirabile.

BACKGROUND: Non-adhesive liquid embolic agents are increasingly gaining importance in the embolization of cerebral arteriovenous malformations (AVMs). We investigated the use of poly (N-isopropylacrylamide) (PNIPAM) as a non-adhesive embolic agent in swine rete mirabile. METHODS: The PNIPAM hydrogel was mixed with iohexol and embolization was performed in swine rete mirabile in 30 animals. The microcatheter was examined after embolization. Follow-up angiography was performed for embolic efficacy after embolization. Embolized retia were examined histopathologically, and the alterations of inside rete and surrounding tissue were observed. RESULTS: The copolymer hydrogel was used for rete embolization in 30 swine, 28 swine survived the procedure, 2 swine died, 1 swine died of cerebrum infarction and the other died of embolic agent reflux into the occipital artery. The inside wall of the microcatheter was smooth, without copolymer adhering to it. Follow-up angiography was performed in 22 swine, there was no rete recanalization in 20 swine and partial rete recanalization in 2 swine because of the trunk embolization of ascending pharyngeal arteries. Histopathologically, the copolymer was found diffused into vessels of 100 - 150 microm in diameter. In acute group, neutrophils scattered surrounding the copolymer and endothelial integrity was observed, without endothelial denuding and necrosis. In subacute and chronic groups, the copolymer was found inside retia, a few mononuclear cells and eosinocytes scattered inside and surrounding it. The muscular layer was loosened with most muscular nuclei degraded. CONCLUSION: Experimental rete embolization with PNIPAM, made radiopaque with iohexol, is technically feasible in swine. Because of its properties, PNIPAM has great potential as a therapeutic non-adhesive embolic agent.