The effect of chemotherapy type and timing among the other factors on patency of totally implantable vascular access devices in colorectal carcinoma.

PURPOSE: Catheter-related complications are observed in infusion of chemotherapy, and these were encountered with targeted therapies. Our principle is to study non-mechanical effects of type and initiation time of chemotherapy among the other factors on patency of totally implantable vascular access devices (TIVAD) inserted in patients with colorectal carcinoma. METHODS: This is a one-center retrospective cohort study. We analyzed TIVAD related complications in 624 patients with colorectal carcinoma. The patients were categorized by chemotherapy type (non-target-directed chemotherapy agents (Group A), bevacizumab (Group B), and cetuximab (Group C)). Additionally, we divided the patients into groups by the time interval between TIVAD insertion and chemotherapy initiation. According to our study, a 3-day period was optimal. Therefore, we named the groups as within 3 days and beyond 3 days, and called this process 3 days cut-off. Age, gender, jugular-subclavian access, platelet count, INR, the types of chemotherapy, and the initiation time of chemotherapy were investigated by survival tests. We compared chemotherapy type groups both one-by-one and combined into one group. RESULTS: The TIVADs were removed due to the complications in 11 patients of Group A, 6 patients of Group B, and 3 patients of Group C. Only chemotherapy type was significant (p = 0.011) in Cox regression test. A clear difference (p = 0.010) was detected between the catheter patency of Group A and combination of Groups B and C, because of skin necrosis and thrombosis. Within 3 days of their first chemotherapy day, an important difference between Group A and Group C (p = 0.013) was observed in the TIVAD patency. The same observation was made between Group A and Group B (p = 0.007). Beyond this period, no major difference was detected (p = 0.341). CONCLUSION: A major effect on catheter patency was detected by using the target-directed chemotherapy agent within 3 days, which should be considered in target-directed chemotherapy.

Diagnostic value of diffusion-weighted magnetic resonance imaging: differentiation of benign and malignant lymph nodes in different regions of the body.

INTRODUCTION: To evaluate the value of diffusion-weighted magnetic resonance imaging compared with conventional magnetic resonance imaging (C-MRI) for the differentiation of benign from malignant lymph nodes in different regions of the body. PATIENTS AND METHODS: A total of 31 patients ranging in age from 18 to 75 years (mean age: 53 years) were included in this study. The patients were examined using a 1.5-T magnetic resonance imaging system with coils chosen according to lymph node locations. Diffusion-weighted images were obtained using the single-shot echo planar sequence and had b values of 50, 500, and 1000 s/mm(2.) The apparent diffusion coefficient (ADC) values were measured from ADC maps. The correlation between the pathological diagnoses and mean ADC values in the benign and malignant lymph node groups were compared using the Mann-Whitney U-test with Bonferroni correction. Receiver operating characteristic (ROC) analysis was performed to evaluate the diagnostic performance of the method. RESULTS: The mean ADC value for benign lymph nodes was 0.97×10(-3) mm(2)/s (range: 0.6-1.2×10(-3) mm(2)/s), and the mean ADC value for malignant lymph nodes was 0.76×10(-3) mm(2)/s (range: 0.3-1.2×10(-3) mm(2)/s) (P<.001). In ROC analysis, the cut-off ADC value for malignant versus benign lymph node differentiation was 0.8×10(-3) mm(2)/s. Using an ADC value of 0.8×10(-3) mm(2)/s, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of the method for differentiating between benign and malignant lymph nodes were 76.4%, 85.7%, 86.6%, 75%, and 80.6%, respectively. The sensitivity, specificity, PPV, NPV, and accuracy of C-MRI were 88.2%, 78.5%, 83.3, 84.6%, and 83.8%, respectively. The sensitivity, specificity, PPV, NPV, and accuracy of C-MRI findings suspicious for malignancy combined with the ADC values were 76.4%, 64.2%, 100%, 81.8%, and 91.6%, respectively. CONCLUSIONS: C-MRI alone remained superior to diffusion-weighted imaging (DWI) and combination C-MRI and DWI for differentiating malignant from benign lymph nodes; however, DWI and ADC calculation may play a role in lymph node characterization.