Body diffusion-weighted MR imaging of uterine endometrial cancer: Is it helpful in the detection of cancer in nonenhanced MR imaging?

Objective

In this study, the authors discussed the feasibility and value of diffusion-weighted (DW) MR imaging in the detection of uterine endometrial cancer in addition to conventional nonenhanced MR images.

Methods and materials

DW images of endometrial cancer in 23 patients were examined by using a 1.5-T MR scanner. This study investigated whether or not DW images offer additional incremental value to conventional nonenhanced MR imaging in comparison with histopathological results. Moreover, the apparent diffusion coefficient (ADC) values were measured in the regions of interest within the endometrial cancer and compared with those of normal endometrium and myometrium in 31 volunteers, leiomyoma in 14 patients and adenomyosis in 10 patients. The Wilcoxon rank sum test was used, with a p < 0.05 considered statistically significant.

Results

In 19 of 23 patients, endometrial cancers were detected only on T2-weighted images. In the remaining 4 patients, of whom two had coexisting leiomyoma, no cancer was detected on T2-weighted images. This corresponds to an 83% detection sensitivity for the carcinomas. When DW images and fused DW images/T2-weighted images were used in addition to the T2-weighted images, cancers were identified in 3 of the remaining 4 patients in addition to the 19 patients (overall detection sensitivity of 96%). The mean ADC value of endometrial cancer (n = 22) was (0.97 ± 0.19) × 10⁻³ mm²/s, which was significantly lower than those of the normal endometrium, myometrium, leiomyoma and adenomyosis (p < 0.05).

Conclusion

DW imaging can be helpful in the detection of uterine endometrial cancer in nonenhanced MR imaging.     

CT assessment of the inferior peripancreatic veins: clinical significance

OBJECTIVE: The purpose of this study was to evaluate and clarify the clinical significance of CT scans of the inferior peripancreatic veins. MATERIALS AND METHODS: Forty-three patients with suspected pancreatic disease underwent three-phase helical CT (collimation, 5 mm; reconstruction, 2.5 mm; scan delay, 30, 60, and 150 sec). The frequency of visualization on CT of the anterior and posterior inferior pancreaticoduodenal veins, inferior pancreaticoduodenal vein, and first jejunal trunk was assessed and correlated with angiographic and pathologic findings. RESULTS: The frequency of visualization of normal inferior peripancreatic veins in patients (n = 22) with a normal portomesenteric vein was 36% for the anteroinferior pancreaticoduodenal vein, 36% for the posteroinferior pancreaticoduodenal vein, 59% for the inferior pancreaticoduodenal vein, and 100% for the first jejunal trunk. The smaller inferior peripancreatic veins were frequently not visualized when normal. In patients (n = 13) with pancreatic carcinoma involving the portosuperior mesenteric vein, all of the inferior peripancreatic veins were dilated and easily recognizable. When the tumor did not involve the portosuperior mesenteric vein but did involve the anteroinferior pancreaticoduodenal, posteroinferior pancreaticoduodenal, and inferior pancreaticoduodenal veins (n = 8), some of the other peripancreatic veins (first jejunal trunk, anterior and posterior superior pancreaticoduodenal veins, and gastrocolic trunk) were dilated. Dilatation indicated tumor extension to the third portion of the duodenum. In patients (n = 7) with involvement of the inferior pancreaticoduodenal vein, the first jejunal trunk, or both without the involvement of the portosuperior mesenteric vein, dilatation of the other peripancreatic veins (anteroinferior pancreaticoduodenal vein, posteroinferior pancreaticoduodenal vein, anterosuperior pancreaticoduodenal vein, posterosuperior pancreaticoduodenal vein, and gastrocolic trunk) indicated tumor invasion of only the second portion of the extrapancreatic nerve plexus (n = 4) and tumor invasion of both the second portion of the extrapancreatic nerve and the mesenteric root (n = 3). CONCLUSION: Dilatation of peripancreatic veins with nonvisualization of inferior peripancreatic veins suggests tumor invasion of peripancreatic tissue.     

Parotid lymph node metastasis from adenocarcinoma of the urachus

The parotid gland and its lymph nodes are frequent sites of metastases from head and neck cancers. However, metastasis from a distant primary below the clavicle is unusual. These originate from a variety of sites, most commonly the lung, kidney and breast. A case of a 59-year-old woman with parotid lymph node metastasis from an adenocarcinoma of the urachus, diagnosed on the basis of two discrete periparotid masses on CT and the patient's history, is presented.     

Prevalence of atherosclerosis in relation to atomic bomb radiation exposure: An RERF Adult Health Study

Purpose: To determine whether exposure to atomic bomb radiation altered the prevalence of asymptomatic atherosclerosis.

Material and methods: In a cross-sectional analysis, we examined aortic arch calcification by plain chest radiography and common carotid artery intima-media thickness (IMT) by ultrasonography among 1804 survivors of the atomic bombing in Hiroshima. We evaluated the association between atherosclerotic changes and radiation exposure, while adjusting for potentially confounding factors.

Results: Multivariate logistic regression analysis showed that aortic arch calcification was significantly associated with radiation exposure (p < 0.05). The odds ratio at 1 Gy was 1.30 (95% confidence interval [CI]: 1.05 – 1.53) for men and 1.31 (95% CI: 1.13 – 1.51) for women. Carotid artery IMT did not vary significantly with radiation dose (p = 0.18).

Conclusion: Radiation dose contributed to the prevalence of aortic atherosclerosis but not carotid artery atherosclerosis in atomic bomb survivors.     

A comparative dosimetric analysis of virtual stereotactic body radiotherapy to high-dose-rate monotherapy for intermediate-risk prostate cancer

PurposeStereotactic body radiotherapy (SBRT) is being used with increasing frequency as definitive treatment of early stage prostate cancer. Much of the justification for its adoption was derived from earlier clinical results using high-dose-rate (HDR) brachytherapy. We determine whether HDR's dosimetry can be achieved by virtual SBRT.Methods and MaterialsPatients with intermediate-risk prostate cancer on a prospective trial evaluating the efficacy of HDR monotherapy treated to dose of 9.5 Gy × 4 fractions were used for this study. A total of 5 patients were used in this analysis. Virtual SBRT plans were developed to reproduce the planning target volume (PTV) HDR dose distributions. Both normal tissue– and PTV-prioritized plans were generated.ResultsFrom the normal tissue–prioritized plan, HDR and virtual SBRT achieved similar PTV V₁₀₀ (93.8% vs. 93.1%, p = 0.20) and V₁₅₀ (40.3% vs. 42.9%, p = 0.69) coverage. However, the PTV V₂₀₀ was not attainable with SBRT (15.2% vs. 0.0%, p < 0.001). The rectal D_max was significantly lower with HDR (94.2% vs. 99.42%, p = 0.05). The rectal D_{2 cc} was also lower (60.8% vs. 71.1%, p = 0.07). Difference in D_{1 cc} urethral dose was not significantly different (87.7% vs. 75.2%, p = 0.33). Comparing the PTV-prioritized plans, the rectal D_max (94.2% vs. 111.1%, p = 0.05) and mean dose (27.1% vs. 33.3%, p = 0.03) were significantly higher using SBRT, and the rectal D_{2 cc} was higher using SBRT (60.8% vs. 81.8%, p = 0.07).ConclusionsHDR achieves significantly higher intraprostatic doses while achieving a lower maximum rectal dose compared with our virtual SBRT treatment planning. Future studies should compare clinical outcomes and toxicity between these modalities.     

The role of thallium-201 single photon emission tomography in the investigation and characterisation of brain tumours in man and their response to treatment

The aim of this study was to characterise brain tumour type and treatment response in relation to the uptake of thallium-201.²⁰¹Tl single photon emission tomography (SPET) was performed in 58 patients with brain tumours. Fifty-six patients were utilised for the statistical comparison of the early and delayed²⁰¹Tl indices expressed as the ratio of tumour to contralateral cerebral hemisphere uptake. The retention index of²⁰¹Tl in the tumour tissue calculated from the early and delayed scans was also analysed. Furthermore, in 56 patients with 58 brain tumours, a comparison was made of the diagnostic value of high²⁰¹Tl uptake and gadolinium diethylene triamine penta-acetic acid (Gd-DTPA) enhancement on MRI scans. Although high²⁰¹Tl uptake was observed in viable malignant gliomas, brain metastases, meningiomas and malignant teratoma, the viable malignant gliomas could not be differentiated from brain metastases and extracerebral tumours by means of²⁰¹Tl indices.²⁰¹Tl SPET failed to diagnose a viable ring-enhanced tumour with a thin rim and small tumours of less than 1.5 cm in diameter visualised by Gd-DTPA-enhanced MRI. In spite of this,²⁰¹Tl SPET appears to be effective for determination of the malignant viability of tumours     

Bone mineral and other bone components in vertebrae evaluated by QCT and MRI

To evaluate the usefulness of assessing bone components using magnetic resonance imaging (MRI), the contributions of bone components, including mineral, fat and collagen, to bone mineral density (BMD) and T1 relaxation time (T1) were studied using phantoms. Excised human vertebrae were also evaluated by quantitative computed tomography (QCT) and MRI. T1 was shortened with increasing quantities of fat and collagen. In water, T1 was significantly affected by bone density, while in oil, T1 became slightly longer as bone density increased. The presence of fat and collagen caused under- and overestimations of BMD, respectively. There was good correlation between T1 and BMD in osteoporotic vertebrae and the vertebrae with long T1 showed an increased content of hematopoietic marrow and/or abnormally increased bone mineral. It was concluded that the experimental data showed that MRI can contribute to the assessment of bone quality.     

Clinical results of super high-dose chemotherapy with peripheral blood stem cell transplantation for patients with advanced germ cell tumor

We examined the clinical results of super high-dose chemotherapy with peripheral blood stem cell transplantation (PBSCT) in 14 patients with poor-risk advanced germ cell tumors. The mean number of nadir white blood cells was 205 +/- 126/microliter; the mean period of number of white blood cells fewer than 1,000/microliter was at 8-10 days (mean +/- SD; 9.2 +/- 0.92). The nadir number of blood platelet cells was 1.7 +/- 0.70 x 10(4)/microliter; the mean period of number of platelet cells fewer than 5 x 10(4)/microliter was at 12.6 +/- 2.17 days. Of 10 patients treated with super high-dose chemotherapy with PBSCT as induction therapy, 8 patients (80%) showed that the serum tumor marker returned within the normal range after super high-dose chemotherapy. Of 8 patients, 7 underwent resection of the residual tumor. Surgical or pathological CR was obtained in 5 of these 7 patients, 4 patients of whom were alive with no evidence of disease 29 to 49 months after initial consultation: the other patient died with recurrence 20 months after initial visit. On the other hand, super high-dose chemotherapy with PBSCT was performed for one patient as consolidation, and for 3 patients with recurrence. Of these 4 patients, one died from disease 6 months after detection of recurrence. The other 3 patients were alive with no evidence of disease at 7-37 months after initial visit. The 1- and 3-year disease-free survival rates were 88% and 72%, respectively. In conclusion, super high-dose chemotherapy with PBSCT can be done safely and could be useful for patients with poor-risk germ cell tumor.     

Pathogenesis of idiopathic scoliosis. Experimental study in rats.

STUDY DESIGN: A radiographic examination of pinealectomized rats to observe the development of scoliosis and halt the condition by administration of melatonin. OBJECTIVES: To discover whether pinealectomy has the same effect in mammals as shown in the chicken, and to determine whether the bipedal condition is important for development of scoliosis. SUMMARY OF BACKGROUND DATA: Pinealectomizing chickens shortly after hatching consistently resulted in scoliosis closely resembling human idiopathic scoliosis. It has not been determined whether this phenomenon is restricted solely to chickens, or if this experimental model is applicable to other animals, especially those more closely related to humans. METHODS: A sham operation in five bipedal rats served as the control in this study. Pinealectomy was performed in 10 quadrupedal rats, pinealectomy in 20 bipedal rats, and pinealectomy with implantation of melatonin pellet in 10 bipedal rats. Spinal radiographs were used to measure the degree of scoliosis at 3 months after surgery. RESULTS: Scoliosis developed only in pinealectomized bipedal rats and not in quadrupedal rats. It developed in none of the sham operation group and in only 1 of 10 pinealectomized bipedal rats with melatonin treatment. CONCLUSIONS: Melatonin deficiency secondary to pinealectomy alone does not produce scoliosis if the quadrupedal condition is maintained. The bipedal condition, such as that in chickens or humans, plays an important role in the development of scoliosis. The findings suggest a critical influence of a postural mechanism for the development of scoliosis.