18F-FDG PET/CT Imaging of Epididymal Smooth Muscle Mass Mimicking Recurrent Lymphoma.

An 84-year-old man with a history of diffuse large B-cell lymphoma in remission who had completed chemotherapy 3 years previously was referred for imaging evaluation of disease recurrence. Abnormal accumulation in the left scrotum was demonstrated on F-FDG PET/CT. Subsequent ultrasonography showed a nodular mass lesion in the left epididymis. He then underwent left orchiectomy. Histopathological examination of the mass diagnosed smooth muscle hyperplasia/hamartoma of the left epididymis. Epididymal smooth muscle hyperplasia/hamartoma should be included as a differential diagnosis for malignant scrotal tumor.

Age-related and zonal anatomical changes of apparent diffusion coefficient values in normal human prostatic tissues.

PURPOSE: To identify age-related changes and differences in the diffusion of water molecules within the prostate, through diffusion-weighted imaging (DWI) of the prostate gland in healthy adult Japanese men. MATERIALS AND METHODS: A total of 114 healthy male volunteers (mean age, 55 years; range, 24-81 years) underwent DWI of the prostate with a single-shot echo-planar imaging (EPI) sequence using b-factors of 0 and 1000 seconds/mm(2). Apparent diffusion coefficient (ADC) values of six locations in the peripheral zone (PZ) and two locations in the central gland (CG) were measured and correlations between region and age were examined. RESULTS: ADC values measured within both PZ and CG regions of the prostate showed a uniform distribution, and no significant differences were found between evaluated regions. However, mean ADC values were 1.64 +/- 0.27 x 10(-3) mm(2)/second for PZ and 1.26 +/- 0.12 x 10(-3) mm(2)/second for CG, representing a significant difference. In addition, significant positive correlations were identified between ADC values for both PZ and CG regions and subject age (r = 0.526, P < 0.0001; r = 0.190, P = 0.0431, respectively). CONCLUSION: ADC values within both PZ and CG regions of the prostate increase with age, and this must be taken into consideration when using DWI in the diagnosis of prostate cancer.

[The diagnosis of osteoporosis].

The diagnosis of Osteoporosis on WHO Technical Report of Prevention and Management of Osteoporosis in 2003, in addition to present status in Japan, has been reviewed. Since Technical Report of Assessment of Fracture Risk and Its Application to Screening for Postmenopausal Osteoporosis was published by WHO in 1994, the field of osteoporosis has progressed remarkably. In particular, in regard to methods of measuring bone mass or density, diagnosis, assessment of fracture risk, and assessment of osteoporosis, this Technical Report describes evidences, confirmed from current many data, and provides informations available to osteoporosis practice. This Report also shows future direction and issues of osteoporosis which should be resolved.

Detection of bone marrow and extramedullary involvement in patients with non-Hodgkin's lymphoma by whole-body MRI: comparison with bone and 67Ga scintigraphies.

The aim of this study was to evaluate the diagnostic potential of whole-body MRI (WB-MRI) for the detection of bone marrow and extramedullary involvement in patients with non-Hodgkin's lymphoma. WB-MRI, which was performed on 34 patients, consisted of the recording of T1-weighted spin-echo images and a fast STIR sequence covering the entire skeleton. The WB-MRI findings for bone marrow and extramedullary involvement were compared with those from (67)Ga and bone scintigraphies and bone marrow biopsy results. Two MRI specialists reviewed the WB-MRI results and two expert radiologists in the field of nuclear medicine reviewed the bone and (67)Ga scintigraphy findings. Bone marrow and extramedullary involvement of non-Hodgkin's lymphoma were confirmed by follow-up radiographs and CT and/or a histological biopsy. The detection rate of WB-MRI was high. More bone marrow involvement was detected by biopsy, and more lesions were detected by scintigraphies. In total, 89 lesions were detected by WB-MRI, whereas 15 were found by biopsy, 5 by (67)Ga scintigraphy, and 14 by bone scintigraphy. WB-MRI could also detect more extramedullary lesions than (67)Ga scintigraphy; i.e., 72 lesions were detected by WB-MRI, whereas 54 were discovered by (67)Ga scintigraphy. WB-MRI is useful for evaluating the involvement of bone marrow and extramedullary lesions throughout the skeleton in patients with non-Hodgkin's lymphoma.

T2-weighted MR imaging of prostate cancer: multishot echo-planar imaging vs fast spin-echo imaging.

The aim of the present study was to assess the performance of pre-biopsy T2-weighted MR imaging using multishot echo-planar imaging (EPI) sequence for visualization of prostate cancer and to compare image quality with that of fast spin-echo (FSE) sequence. Thirty-nine patients with suspected prostate cancer and one healthy male volunteer were examined on a 1.5-T MR scanner equipped with a pelvic phased-array coil. Axial MR images were obtained using multishot EPI sequence with a multishot number of 16 and FSE sequence without fat suppression. Paired EPI and FSE images were independently evaluated by three radiologists. Furthermore, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were compared between EPI and FSE images of 12 pathologically proven lesions of prostate cancer. Delineation of the periprostatic venous plexus, prostate zonal anatomy, and seminal vesicle on EPI was graded to be superior/inferior to FSE in 15.8/0, 14.6/0, and 21.5/4.3% of cases, respectively. On the other hand, delineation of the neurovascular bundle was superior/inferior to FSE in 2.6/13.2% of cases. The SNR and CNR of prostate cancer on EPI were significantly higher than those on FSE (7.99 +/- 2.51 vs 3.36 +/- 0.58, p<0.0001, and 5.51 +/- 2.02 vs 2.21 +/- 0.79, p<0.0001, respectively). In conclusion, multishot EPI has higher quality of contrast resolution for imaging of prostate cancer compared with FSE and would have the potential usefulness in the detection of prostate cancer, although these results obtained with a phased-array coil cannot be extrapolated to examinations performed with an endorectal coil.