A B S T R A C T The dihydrotestosterone content of normal peripheral and benign hyperplastic prostates was measured in tissue obtained at open surgical procedures on 29 men of ages 36 to 82 yr. The dihydrotestosterone content in normal prostates (mean±SE, 5.1±0.4 ng/g tissue) and in benign hyperplastic prostates (5.0±0.4) was similar. In 11 patients in whom both normal and hyperplastic prostatic tissue was harvested simultaneously at the same operation, there was no significant difference in the content of dihydrotestosterone in the two types of tissue. These findings fail to confirm the widespread belief that dihydrotestosterone content is elevated in benign hyperplastic prostates. Our data differ from the reported literature in one major respect: the dihydrotestosterone content of normal peripheral prostate in this study is three to four times higher than previously reported. This difference between the present and earlier studies was resolved by experiments performed on cadavers, which were the source of normal prostatic tissue used by other investigators. Dihydrotestosterone content was measured in seven cadavers ranging in age from 19 research into the etiology of BPH has focused on factors that may be responsible for this accumulation of supranormal levels of dihydrotestosterone and the mechanismn by which this induces prostatic hyperplasia. Recently, while investigating the value of dihydrotestosterone content as a marker for the hormonal responsiveness of prostatic cancer, we noted that the content of dihydrotestosterone in normal and benign hyperplastic tissues obtained at open surgical procedures was similar. In reviewing the literature to determine why we were unable to confirm the findings of others, we learned that the "elevated" levels of dihydrotestosterone in BPH which were reported by others were based upon measurements performed on surgically removed specimens, whereas the "low levels" of dihydrotestosterone in normal tissue were based upon measurements performed on tissues obtained at autopsy (4-8). This observation suggested that the conditions of tissue harvesting may have significantly influenced the endogenous levels of androgens within the prostate. To explore this possibility, the present study was undertaken. Dihydrotestosterone content in normal and benign hyperplastic tissue has been measured in tissues removed at open surgical procedures and at autopsy on men of varying ages. These data suggest that the dihydrotestosterone content of prostatic tissue removed at autopsy is abnormally low. This finding was confirmed by in vitro incubations of prostatic tissue at 37°C that demonstrated rapid disappearance of dihydrotestosterone. These data indicate that when prostatic tissue is harvested appropriately, the dihydrotestosterone content of normal peripheral and hyperplastic tissues is the same. This finding should influence future research into the etiology of BPH. carcinoma of the prostate (eight patients), and radical cystoprostatectomy for the treatment of carcinoma of the bladder (15 ...
The sonographic findings in eight children with surgically proved cystic hygroma were reviewed and correlated with the pathologic specimens. Six tumors occurred in the neck, one occurred in the axilla, and one involved the soft tissues of the thigh, scrotum, and pelvis. A cystic hygroma characteristically appears as a multiloculated cystic mass with septa of variable thickness that contain solid components arising from the cyst wall or the septa. Correlation of the sonogram with the pathologic specimen demonstrated that the echogenic component corresponded to a cluster of abnormal lymphatic channels, too small to be resolved with ultrasound. Large lesions had ill-defined boundaries, with cystic components dissecting between normal tissue planes. Sonographically, one can usually differentiate these tumors from other cervical masses, especially soft-tissue hemangiomas. Sonography is also helpful in determining the extent of the lesion before surgery and in assessing postoperative complications and recurrences.
Paralysis seen in children with myelomeningocele has been attributed to congenital myelodysplasia. We suspected that paralysis may be due in part to a spinal cord injury caused by exposure of the neural tube to the amniotic fluid. This hypothesis was tested using a fetal rat model of surgically created dysraphism. Each pup from the experimental group of rats in which the spinal cord was intentionally exposed to the amniotic fluid was born with severe deformity and weakness of the hind limbs and tail. Control fetal rats, subjected to the same procedure without directly exposing the spinal cord to the intrauterine environment, were normal at birth. Histological studies of the exposed spinal cord revealed extensive erosion and necrosis, findings similar to those described in children with myelomeningocele. We therefore propose a "two-hit" hypothesis to explain the paralysis seen in children with myelomeningocele: congenital myelodysplasia complicated by an intrauterine spinal cord injury. Intrauterine protection of the exposed spinal cord might prevent some or all of the paralysis. The possible implications of these findings for the future treatment of myelomeningocele are discussed.
The authors report a case of fulminant, metastatic lung calcification leading to progressive respiratory failure in a patient who underwent unsuccessful renal transplantation. Premortem computed tomographic (CT) examination of the lung demonstrated the presence of high-attenuation (greater than 100 HU) parenchymal consolidation, compatible with metastatic calcium deposition. By depicting significant pulmonary calcification not seen on conventional radiographs, CT facilitated identification of an important contributing factor to the patient's respiratory failure and death.
Most melanoma-positive SNs contain minute tumor volumes. Tumor thickness and patterns of SN metastases may not be predictive of tumor burden or the presence of positive NSNs.
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