Randomized prospective evaluation of extended versus limited lymph node dissection in patients with clinically localized prostate cancer

PURPOSE: The low rate of pelvic node metastasis in most contemporary series of patients undergoing radical prostatectomy for carcinoma of the prostate has been attributed to earlier and better patient selection than historical series. Alternatively, it has been suggested that the limited dissection commonly performed misses nodal metastasis in a substantial number of patients. To assess the value of an extended node dissection in detecting nodal metastasis, we performed a randomized prospective study. MATERIALS AND METHODS: A total of 123 patients undergoing radical prostatectomy were randomized to an extended node dissection on the right versus the left side of the pelvis with the other side being a limited dissection. The extended dissection included removal of all external iliac nodes to a point above the bifurcation of the common iliac artery, the obturator nodes and the presacral nodes. The limited dissection included only the nodes along the external iliac vein and obturator nerve. RESULTS: Mean patient age was 61 years. Clinical stage was T1c in 88 patients (72%), T2a in 26 (21%), T2b in 7 (6%) and T3 in 2 (1%). Mean preoperative prostate specific antigen was 7.4 ng./ml. Pelvic lymph node metastasis was histologically confirmed in 8 patients (6.5%). Positive nodes were found on the side of the extended dissection in 4 patients, on the side of the limited dissection in 3 and on both sides in 1. Complications possibly attributable to the node dissection included lymphocele in 4 patients, lower extremity edema in 5, deep venous thrombosis in 2, ureteral injury in 1 and pelvic abscess in 1. These complications occurred 3 times more often on the side of the extended dissection (p = 0.08). CONCLUSIONS: Extended node dissection in contemporary series of patients undergoing radical prostatectomy identifies few with nodal metastases not found by a more limited dissection. A trend toward an increased risk of complications attributable to the lymphadenectomy occurs with an extended dissection.     

Usefulness of low-dose spiral CT of the chest in regular follow-up of postoperative non-small cell lung cancer patients: Preliminary report

OBJECTIVES: There is no consensus for the best postoperative follow-up in patients after complete resection of non-small cell lung cancer. Low-dose computed tomography of chest proves valuable in screening primary lung cancer and may be a useful tool in postoperative surveillance. METHODS: In part 1, 30 patients who underwent surgical resection of non-small cell lung cancer and were at the first (n = 14), second (n = 9), or fifth (n = 7) annual postoperative surveillance were selected chronologically and subjected to chest radiography, low-dose computed tomography, and standard-dose computed tomography to verify the diagnostic accuracy of low-dose computed tomography. In part 2, 43 patients were prospectively enrolled and followed up regularly after complete resection of non-small cell lung cancer. The follow-up protocol included physical examination, sputum cytology, serum carcinoembryonic antigen, chest radiography, and low-dose computed tomography every 3 months in the first 2 years postoperatively until tumor recurrence. RESULTS: In part 1, tumor recurrence was detected by standard-dose computed tomography in 7 cases. Low-dose computed tomography and chest radiography missed 1 and 5 of 7 cases, respectively. In part 2, tumor recurrence was found in 14 cases with 19 metastatic sites. Thirteen of the 14 (92.9%) cases were detected by scheduled visiting and 11 (78.6%) detected by low-dose computed tomography including the 7 without symptoms. Of the 19 recurrent sites found in 14 patients, 11 ones (57.9%) were detected by low-dose computed tomography. CONCLUSIONS: Low-dose computed tomography may be of considerable value in early detection of tumor recurrence in postoperative non-small cell lung cancer patients. Further large prospective studies are needed to verify this issue.     

The effects of intrathecal tramadol on spinal somatosensory-evoked potentials and motor-evoked responses in rats

Tramadol has been proven to exert a local anesthetic-type effect on peripheral nerves in both clinical and laboratory studies. In this study, we evaluated the effects of tramadol on sensory and motor neural conduction when administered intrathecally in the rat. Tramadol (0, 1, or 2 mg) was administered through an intrathecal catheter. Spinal somatosensory-evoked potentials (SSEPs) were recorded at the thoracolumbar junction after stimulation of the sciatic nerve. An evoked compound muscle action potential (CMAP) was recorded in the intrinsic muscles of the foot in response to electric stimulation of the lower thoracic (T1213) interspinous space. Both SSEP and CMAP were obtained before drug application as the pretreatment baseline and at 5, 15, and 30 min after treatment, and at 30- or 60-min intervals thereafter for another 4.5 h. SSEP was averaged from 20 responses, whereas CMAP was obtained from a single stimulation. Reproducible SSEPs and CMAP were consistently recorded in all rats. Intrathecal tramadol dose-dependently reduced the amplitude and delayed the latency in both SSEPs and CMAP. Generally, the suppressive effects occurred immediately after injection and recovered over 2 h. Combined administration with 20 micro g of intrathecal naloxone did not attenuate the inhibition of spinal SSEPs. We conclude that intrathecal tramadol causes a dose-related suppressive effect on both sensory and motor neural conduction in the spinal cord. IMPLICATIONS: Spinal somatosensory-evoked potentials and evoked compound muscle action potential were used to evaluate the effects of intrathecal tramadol on sensory and motor neural conduction. Intrathecal tramadol dose-dependently reduced the amplitude and delayed the latency of both spinal somatosensory-evoked potentials and compound muscle action potential. These results indicate that tramadol exerts a dose-related central neural blockade.     

一次性和反复性力竭运动后不同时相大鼠心肌Kir6.1的表达

目的:探讨力竭运动后不同时相大鼠心肌Kir6.1基因表达的变化特点.方法:健康雄性SD大鼠80只,分为一次力竭游泳运动组和2周反复力竭游泳运动组及相应安静对照组.依据Thomas实验方案,建立不同程度的运动性心肌微损伤实验动物模型.力竭运动后,分时相取材,采用RT-PCR定量反转录方法分析心肌离子通道亚基Kir6.1在mRNA表达水平的变化.结果:(1)一次性力竭运动和反复力竭运动后24小时,心房肌中Kir6.1基因表达均显著下降(P＜0.05).(2)一次性力竭运动和反复力竭运动后4、12、24小时,心室肌中Kir6.1基因表达均显著升高(P＜0.01).结论:(1)力竭运动后,心室肌Kir6.1基因的表达水平总体呈上调变化,心房肌Kir6.1基因的表达水平在运动后24小时呈下调变化.(2)心室肌Kir6.1基因表达的上调对运动心肌有保护作用,而心房肌Kir6.1基因表达下调是心房肌易损伤的机制之一.     

Features of non-small cell lung carcinomas overlooked at digital chest radiography

PURPOSE: To examine the imaging features of non-small cell lung carcinomas (NSCLC) overlooked at digital chest radiography (dCXR), and compare general and thoracic radiologists' performance for lung carcinoma detection at dCXR. METHODS: Frontal and lateral dCXR from 30 consecutive patients with lung carcinoma overlooked during initial interpretation and 30 normal controls were independently retrospectively reviewed by two blinded thoracic radiologists and, in a separate review, three blinded general radiologists. The location, size, histopathology, borders, presence of superimposed structures, and lesion opacity were recorded. Interobserver agreement was calculated, and the detection performance between thoracic and general radiologists was compared. RESULTS: The average patient age was 67.9 years (range 47-82 years). The average size of carcinomas missed by the thoracic radiologists was 18.1mm (range 10-32 mm). Lesion margins were circumscribed in 29% (2/7), and 71% (5/7) of missed lesions were obscured by anatomical superimposition. Seventy-one percent (5/7) of missed lesions were solid nodules on computed tomography (CT) images. Forty-three percent of lesions were located in the upper lobes and 63% were adenocarcinomas. Compared with general radiologists, the seven NSCLC missed by the thoracic radiologists tended to be smaller (p=0.063), had significantly lower CT density measurements (-92.4+/-87.5 HU versus -70+/-87.2 HU, p=0.050), and more commonly had an ill-defined margin (p=0.026). The clinical stage of the overlooked lesions did not differ between the two groups (p=0.480). CONCLUSIONS: The lesion size, location, conspicuity, and histopathology impact the likelihood of lung carcinoma detection at dCXR in a fashion similar to that of conventional film-screen techniques.     

<Superscript>18</Superscript>F-FDG PET for the lymph node staging of non-small cell lung cancer in a tuberculosis-endemic country: <Emphasis Type="Italic">Is dual time point imaging worth the effort?</Emphasis>

PURPOSE: This study was to compare (18)F-FDG positron emission tomography (PET) with thoracic contrast-enhanced CT (CECT) in the ability of lymph node (LN) staging non-small cell lung cancer (NSCLC) in a tuberculosis-prevalent country. The usefulness of dual time point PET imaging (DTPI) in NSCLC nodal staging was also evaluated. METHODS: We reviewed 96 NSCLC patients (mean age, 65.3 +/- 11.7 years) who had received PET studies before their surgery. DTPI were performed on 37 patients (mean age, 64.8 +/- 12.2 years) who received an additional scan of thorax 3 h after tracer injection. The accuracies of nodal staging by CECT and PET were evaluated according to final histopathology of hilar and mediastinal LN resected by surgery. RESULTS: The accuracy for nodal staging by CECT was 65.6% and that by PET was 82.3% (p < 0.05). Six patients were over-staged and 11 were under-staged by PET. Tuberculosis (n = 3, 50%) were mostly responsible for false-positive, while small tumor foci (n = 7, 63.6%) were mostly accountable for false-negative. For the 37 patients with DTPI, 45 min standardized uptake value (SUV) and 3 h SUV for negative LNs are significantly lower than those for positive LNs (p < 0.0001). Nevertheless, the retention index (RI) showed no significant difference between these two groups. CONCLUSIONS: Our study demonstrates that PET is more accurate than CECT in LN staging NSCLC patients in Taiwan where TB is still prevalent. Semi-quantitative SUV method or DTPI with RI does not result in better diagnostic accuracy than visual analysis of PET images.     

Detection of multiple myeloma by PET/CT in a patient with colon cancer

A 76-year-old man with previous sigmoid colon resection for adenocarcinoma had low back pain for 2 months. Whole-body bone scintigraphy showed multiple focal Tc-99m methylene diphosphonate (MDP)-avid lesions in both rib cages and 3 lumbar vertebrae, indicating metastases. F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) imaging was performed for further evaluation of this possible metastatic disease and demonstrated the lumbar and costal metastases and several hypermetabolic areas in the pelvic bones, multiple thoracic vertebrae, both shoulders, and the right femur. Histopathologic examination of the right-sided iliac crest, however, revealed multiple myeloma.     

Adaptations in trabecular bone microarchitecture in Olympic athletes determined by 7T MRI

PURPOSE: To produce in vivo high-resolution images of the knee and to determine the feasibility of using 7T MR to detect changes in trabecular bone microarchitecture in elite athletes (Olympic fencers) who undergo high impact activity. MATERIALS AND METHODS: The dominant knees of four males from the U.S. Olympic Fencing Team and three matched healthy male controls were scanned in a 7T whole-body scanner using a quadrature knee coil with three-dimensional (3D) fast low angle shot (FLASH): 50 axial images at the distal femur (0.156 mm x 0.156 mm) and 80 axial images at the knee joint (0.195 mm x 0.195 mm). Bone volume fraction (BVF) and marrow volume fraction (MVF) images were computed and fuzzy distance transform (FDT) and digital topological analysis (DTA) were applied to determine: trabecular number (Tb.N), trabecular thickness (Tb.Th), and trabecular separation (Tb.Sp); BVF (BV/TV); trabecular and marrow space surface-to-curve ratio (SC, marker of plate to rod ratio); and trabecular and marrow space erosion index (EI, inverse marker for network connectivity). Quadriceps muscle volume (MV) was calculated as well. We calculated group means and performed two-tailed t-tests to determine statistical significance. RESULTS: Compared to controls, fencers had: decreased Tb.Sp (P = 0.0082 at femur, P = 0.051 at joint); increased Tb.N (P < 0.05 at both femur and joint) and BV/TV (P < 0.001 at both femur and joint); increased trabecular SC and decreased marrow space SC (P < 0.01 at both femur and joint); decreased trabecular EI and increased marrow space EI (P < 0.01 at both femur and joint); and increased MV (P = 0.038). There was no difference in Tb.Th at the distal femur (P = 0.92) or joint (P = 0.71) between groups. CONCLUSION: To our knowledge, this is the first study to perform 7T MRI of the knee in vivo. Elite athletes who undergo high impact activity have increased MV and improved trabecular bone structure compared to controls.     

Systematic evaluation of sensitivity and specificity of sibship determination by using 15 STR loci

Paternity disputes and other forms of kinship testing are routinely resolved using short tandem repeat (STR) DNA loci. Sibship determination is encountered in instances where the DNA profiles of two individuals are compared to determine if they are siblings. If either parent is available for testing then the situation is simplified but if neither parent of the two individuals is available for DNA testing, a combined sibling indices (CSI) for the determination of sibship between two people can be determined. Support for kinship is also based upon the sharing of alleles, particularly when both alleles are shared at the same locus, termed two-allele-sharing-loci (TASL). We report on the combination of CSI and TASL to enhance the determination of sibship. The 15 STR loci that comprise the Identifiler loci were applied to three populations using pairs of full siblings or unrelated pairs. Based upon the data obtained, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) can be applied to determining whether two DNA profiles come from full or non-sibling pairs. This report highlights the problems inherent in this form of kinship testing and recommends a combination use of CSI and TASL for sibship determination.     

Needle tract implantation after percutaneous interventional procedures in hepatocellular carcinomas: lessons learned from a 10-year experience.

Percutaneous interventional procedures under image guidance, such as biopsy, ethanol injection therapy, and radiofrequency ablation play important roles in the management of hepatocellular carcinomas. Although uncommon, the procedures may result in tumor implantation along the needle tract, which is a major delayed complication. Implanted tumors usually appear as one or a few, round or oval-shaped, enhancing nodules along the needle tract on CT, from the intraperitoneum through the intercostal or abdominal muscles to the subcutaneous or cutaneous tissues. Radiologists should understand the mechanisms and risk factors of needle tract implantation, minimize this complication, and also pay attention to the presence of implanted tumors along the needle tract during follow-up.