Increase of CD8+ T-effector memory cells in peripheral blood of patients with relapsing-remitting multiple sclerosis compared to healthy controls.

CCR7 and CD45RA expression on CD4+ and CD8+ T-cells in blood (PB) of 16 patients with multiple sclerosis (MS) and 16 healthy controls and cerebrospinal fluid (CSF) of 10 patients suffering from MS were analysed by flow cytometric measurements. T-cells were divided by their distinct homing potentials and effector-functions in three groups: naïve T-cells (CCR7+, CD45RA+), central memory T-cells (TCM) (CCR7+, CD45RA-) and effector memory T-cells (TEM) (CCR7-, CD45RA-). There was a significant increase of CD8+ TEM-cells in PB of MS patients compared to healthy controls, indicating systemic immune activation. Further we found a relative depletion of CD8+ TEM-cells in CSF of MS patients compared to matching blood samples, suggesting that these cells represent the effector arm of the immune response and infiltrate the brain tissue at the sites of inflammation.

[Contrast media kinetic in multi-slice helical CT cannot detect rectal cancer recurrence with certainty]. / Die Kontrastmittelkinetik im Mehrzeilen-Spiral-CT kann das Rektumkarzinomrezidiv nicht sicher detektieren.

PURPOSE: Evaluation of different parameters of contrast media enhancement for the differentiation between scar tissue and local recurrence of rectal cancer. MATERIALS AND METHODS: We included 83 patients after operation and radiotherapy of rectal cancer. In total, 20 local recurrences were diagnosed. After administration of 75 ml Iopromide (370 mg/ml) and a delay of 65 s, the whole abdomen and pelvis were scanned in a collimation of 4 x 2.5 mm and 12.5 mm table feed per rotation. The suspected tissue was marked by the freehand ROI option in every slice and the minimum, average and maximum densities were calculated. A local recurrence was suspected if maximum density was higher than 90 HU after admission of contrast media. In addition we calculated the maximum difference of density as the difference between maximum and minimum density. RESULTS: The minimum and average densities showed no reliable differences for patients with or without local recurrence (minimum density 4 HU ( +/- 12 HU) vs. 13 HU ( +/- 21 HU), P = 0.23, average density 48 HU ( +/- 10 HU), vs. 48 HU ( +/- 17 HU)), P = 0.52. The patients suffering from local recurrence showed higher maximum densities and a higher maximum difference than the patients without recurrence (maximum density 111 HU ( +/- 13 HU) vs. 81 HU ( +/- 24 HU), P = 0.02, maximum difference 103 HU ( +/- 20 HU) vs. 76 HU ( +/- 31 HU), P = 0.06. These differences were not significant. We calculated a sensitivity of 0.6, a specificity of 0.83, a positive predictive value of 0.52 and an accuracy of 0.77. CONCLUSION: It is not possible to diagnose a recurrent rectal cancer by density values alone.

[Improvements in detection of rectal cancer recurrence by multiplanar reconstruction]. / Verbesserte Rezidiverkennbarkeit mittels multiplanarer Rekonstruktion beim Rektumkarzinom in der Mehrzeilenspiralcomputertomographie.

PURPOSE: To evaluate the advantages of multiplanar reconstruction and different axial slice thickness in diagnostic of rectal cancer recurrence after operation and radiotherapy. METHOD: We included 83 patients after operation and radiotherapy of rectal cancer in this study. All patients got a minimum of three CT-examinations in their follow-up program. A total of 294 CT-scans were evaluated. Each examination was reviewed by two experienced radiologists in respect to recurrence. Each examination was presented in axial reconstruction with a slice sickness of 8, 5, and 1.25 mm and in multiplanar reconstruction. The sensitivity, specificity, positive predictive value and accuracy were calculated. RESULTS: Multiplanar reconstructions showed better results for the detection of recurrence than axial reconstruction. A reduced slice thickness did not lead to better results in axial reconstruction. Multiplanar reconstruction showed a sensitivity of 0.88, a specificity of 0.98, an accuracy of 0.96 and a positive predictive value of 0,94, for axial reconstruction we calculated: 0.82, 0.97, 0.94 and 0.88, respectively. Sensitivity and accuracy showed a significant increase after the first and second examination. CONCLUSION: Multiplanar reconstructions allow a significant better detection of rectal cancer recurrence when compared to axial reconstructions. Thinner axial slice thickness shows no diagnostic advantage.