B cell lymphoma: a case with localized involvement of the prostate on F-18-FDG examination.

An 80-year-old man had symptoms of urinary retention. Biopsy of the prostate revealed B cell lymphoma. To evaluate the extent of the disease, an F-18 FDG study was performed with positron emission tomography/computed tomography (CT). One hour after intravenous administration of 18.5 mCi F-18 FDG, imaging was carried out from the skull base to the upper thigh. An area of moderately increased activity was noted within the prostate bed. A noncontrast CT, for attenuation correction and anatomic localization, revealed maintenance of fat planes around the prostate, indicating disease localized to that organ. Hence, a B cell lymphoma had been localized to the prostate.

Asymmetric tongue muscle uptake of F-18 FDG: possible marker for cranial nerve XII paralysis.

A 58-year-old woman, with nonsmall cell carcinoma, had multiple metastasis on 2-F-18 FDG positron emission tomography imaging. The right hemitongue had increased activity as compared with the left. This was not the result of the presence of a metastasis to the tongue, as shown by a negative computed tomography scan of the region and failure to demonstrate a lesion over a period of weeks. Uptake was likely related to right hemiglossal muscle activity. This was made more apparent by decreased uptake on the opposite side of the tongue (up to the midline) as a result of left cranial nerve XII paralysis.

Supine versus prone injection of Tc-99m MAA: evidence of thoracic compression or fluid shift.

After a cesarean section, a woman had sharp left chest pain that radiated to the arm and was worse with inspiration. A chest radiograph revealed minimal left lung base atelectasis. A total of 5 mCi (185 mBq) Tc-99m macroaggregated albumin (MAA) was injected with the patient supine. A posterior oblique perfusion lung image revealed nearly absent perfusion of the left lung base. The patient was then injected with an equal quantity of Tc-99m MAA while prone. Images now demonstrated perfusion of the left lower lung. This might represent redistribution of fluid obscured by the atelectatic area, or the relief of pressure on pulmonary arteries to the left lower lobe by positional change.

Male/female weight of internal organs: examination across multiple populations.

For internal organ weights in the 50th percentile, the male/female weight relationship was examined by use of autopsy data in eight populations. Values were closely coupled (P < 0.001), so that male organ weight could be expressed as a linear function of the corresponding female organ. A variant, in a reported population from India, was noted. The concept of "allometric mass exponent" was also applied to relating male/female organ weights, with close agreement. To examine if findings correlated with height and weight of the whole body, male height was expressed as a function of the female value in each population. There was close agreement. Correlation was also noted when male body weight was given as a function of female body weight.

Pubertal height gain: male-female and interpopulation comparisons.

Data are not available as to the exact age of the start of the pubertal growth spurt (or age at its conclusion) in various populations. As an initial approach, contribution of the pubertal gain to overall height was examined, using age 9 as the start of puberty in girls and age 11 in boys. Data were analyzed from 11 reports (single assays on five populations, two studies on a group analyzed 30 years apart, and four studies of a population spread over 31 years. Using the percent contribution to overall height, pubertal growth showed a close agreement between the populations as well as between male and female values (overall p < 0.003). Results for both sexes clustered around a narrow range. Pubertal growth for the 50th percentile, expressed as a percent contribution to overall height, may approach a biologic invariant. The value of percent contribution of pubertal growth to final height, did not show a secular trend.

Cessation of reproduction: an analytic view of menopause.

While there is evidence for genetic control of ovarian and follicular development, only recently have reports appeared on genetic components involved in ovarian failure. Unlike predictions of a stable population, age at menarche is decreasing, while female life span is increasing. This leads to examination of genotype-environment interactions. Evolution of the large human brain size has been accompanied by a reduction in size of the gastrointestinal tract. Consequences, in terms of altered diet and effects on menarche/menstruation/menopause were discussed. In the earliest days of human evolution, genotoxic agents and marginal diets could have produced heritable changes in cessation of menstruation. Toxic alterations may still be apparent, such as epidemiological studies on the effects of smoking on age at menopause. Attempts to reconstruct some of the recent past history, from coprolites to findings in frozen human specimens, have to be extended still further into the past.

Bone and In-111 octreotide imaging in oncogenic osteomalacia: a case report.

Osteoporosis associated with aging is considered the most common cause of bone mineral loss. Osteomalacia, abnormal bone loss with excess osteoid formation, is another cause. A 46-year-old man was examined for chronic hip and lower extremity pain that had not been relieved by nonsteroidal anti-inflammatory drugs or steroids. A bone scan revealed multiple foci of activity. The serum calcium level was normal, but phosphorus values were low. These results did not correspond with the indications for typical hyperparathyroid disease, so another cause was sought. An In-111 octreotide scan showed a focus in the right humeral head. At surgery, a phosphaturic tumor of mesenchymal origin was partially resected. Oncogenic osteomalacia is related to secretion of a phosphaturic material from a fibroblast growth factor.

Migration of Tc-99m DTPA from the cerebral ventricle to the subarachnoid space.

A 70-year-old woman was examined because of increasing problems with cognition. She had a history of a cerebral shunt placed surgically 10 years previously. Introduction of Tc-99m DTPA directly into the ventricular cavity revealed good ventricular distribution, followed by progression downward, as though into a previous ventriculoperitoneal shunt. However, a chest radiograph revealed what appeared to be a shunt tube in the right atrium. Delayed lateral images showed activity in proximity to the vertebral column, indicating migration of tracer and cerebrospinal fluid into the dorsal and lumbar subarachnoid space.