CT scanning for definitive radiotherapy planning of prostate cancer: necessity or nicety? Results from survey of radiation oncologists working at different institutions in Australasia

Interactive computerised tomographic (CT) planning techniques offer the prospect of better anatomical localisation, more consistent tumour coverage, and limiting normal tissue dose. However, its value in the management of prostate cancer remains undefined. The present study addresses the impact of planning CT on the designated target volumes for localised carcinoma of the prostate at a multi-institution national level. Nine radiation oncologists from different centres in Australia and New Zealand were asked to designate a target volume on five sample patients with different disease stages (A2-C2) using both conventional cystogram films and planning CT scans. Target volumes estimated by CT means in this study differed by more than 10% from those estimated by conventional means in 75.6% of instances, being smaller in 55.6%. Volumes varied widely between individual radiation oncologists, both using conventional planning and CT information. These variations were found to exceed any differences in the volume caused by the planning technique itself. Results from this survey suggest that volumes appear to change more according to the individual radiation oncologist rather than to any other factor. In most or all of the sample cases six of nine radiation oncologists defined the borders of their CT volumes to be either consistently smaller (5 out of 9) or greater (1 out of 9) than their conventionally defined borders. The results of this survey are potentially important and warrant repetition with larger sample numbers in other countries where interactive CT planning facilities exist, both with and without diagnostic radiological input, to exclude similar variation and to define causes for any variations that do become apparent.     

Effector mechanisms of human monocyte-mediated tumor cytotoxicity in vitro: biochemical, functional, and serological characterization of cytotoxins produced by peripheral blood monocytes isolated by counterflow elutriation

Human peripheral blood monocytes, isolated in high purity by centrifugal counterflow elutriation from normal donors, release cell toxins, herein termed human monocyte toxins (HMTs) upon further stimulation in vitro. The principal form of HMTs produced by these human peripheral blood monocytes has been subjected to biochemical, functional, and serological characterization. By molecular sieving on Sephacryl S-200, HMTs can be resolved into two molecular weight classes. The larger, termed alpha, has a molecular weight of about 120,000, and the smaller, termed beta, has a molecular weight of about 65,000. The beta class is by far the most predominant species and has been further characterized. Chromatofocusing of beta-HMT indicates a slightly acidic nature, since this species is eluted at pH 5.8. Functional characterization of beta-HMT suggests that it is not a trypsin-like protease, since neither alpha,N-tosyl-L-lysylchloromethylketone nor alpha,N-tosyl-L-arginyl methyl ester are capable of causing significant inhibition of the cell-lytic activity of the molecule. Furthermore, cell lysis induced by beta-HMT appears to be independent of oxygen-dependent mechanisms, since catalase is incapable of blocking lysis, and since hydrogen peroxide and superoxide anion are not produced in detectable amounts during lysis. Finally, beta-HMT does not appear to be an arginase, since it is active in arginine-containing medium and further addition of arginine to the assay medium does not inhibit lysis significantly. beta-HMT is serologically related to recombinant human tumor necrosis factor (rHuTNF), since its cell lytic activity can be blocked by a rabbit antiserum against rHuTNF. However, much higher levels of this antiserum are required to achieve neutralization than are required to neutralize a comparable number of cell lytic units of rHuTNF. Furthermore, the results of preliminary immunoprecipitation experiments using the rabbit anti-rHuTNF antiserum suggest that a peptide in the Mr 60,000-70,000 range is recognized by this serum, whereas no signal at Mr 17,000 corresponding to rHuTNF is detectable. Thus, human peripheral blood monocytes can be triggered to release cell toxins, the principal form of which, beta-HMT, appears to be functionally distinct from the cytotoxic proteases reported in the murine system and appears to be molecularly distinct from, but serologically related to rHuTNF.     

Outcome of children with fetal, neonatal or childhood diagnosis of isolated congenital atrioventricular block. A single institution's experience of 30 years.

OBJECTIVES: We reviewed our institution's experience with isolated (congenital) third-degree atrioventricular block (CAVB) to identify pre- and post-natal predictors of mortality and the requirement for pacemakers in infancy and childhood. BACKGROUND: Because of the relative rarity of the disease, there is a paucity of data concerning the outcome of fetuses and children with isolated CAVB. METHODS: The medical records of all cases of CAVB encountered at our institution from January 1965 to December 1998 were analyzed. RESULTS: Of 102 cases identified, 29 were diagnosed in utero (F) at 26.1 +/- 5.6 weeks gestation, 33 as neonates (N; < or = 28 days), and 40 as children (C) at 5.7 +/- 4.8 years of age. Anti-Ro and/or anti-La were present in 95% of F and 90% of N, but only in 5% of C mothers tested (p < 0.0001). Patients with CAVB having F, N and C diagnosis had a mortality of 43%, 6% and 0%, respectively, in the first two decades of life. Increased mortality risk was associated with a fetal diagnosis of CAVB (13/15 deaths; p < 0.05), fetal hydrops (6/6 cases; p < 0.0001), endocardial fibroelastosis (5/5 cases; p < 0.0001) and delivery at < or = 32 weeks (4/6 cases; p < 0.05). Timing of pacemaker implantation differed significantly among F versus N (p < 0.05) and N versus C (p < 0.001) cases. At 20 years of age only 11% and 12% of CAVB patients with N and C diagnosis, respectively, were not paced. CONCLUSIONS: Pre-natal diagnosis of CAVB is associated with high fetal and neonatal mortality. Among survivors, whether the diagnosis is made before or after birth, most undergo pacemaker implantation by adulthood, with earlier intervention and a significantly greater need for reintervention among those diagnosed in utero.     

The hip or not.

Pathologies within the ileopsoas compartment can present as hip pain and as such can be mistaken for diseases of the hip joint. Radiological investigations are useful in helping to differentiate between these pathologies.     

Luteal cysts and unexplained infertility: biochemical and ultrasonic evaluation

A prospective, controlled study of ovarian function using ovarian ultrasound and daily plasma hormone estimations (estradiol, progesterone [P], follicle-stimulating hormone [FSH], luteinizing hormone [LH]) was carried out on 175 spontaneously cycling patients with unexplained infertility. Forty-one (23.4%) demonstrated luteal phase cyst formation. In 21 cycles the dominant follicle reduced in size after the LH peak (cystic corpus luteum cycles), and in 20 no shrinkage was seen (luteinized unruptured follicles). Progesterone concentrations in the early luteal phase were significantly reduced in the luteinized unruptured follicle cycles. Elevation in plasma FSH was seen in the early follicular and luteal phases of both cyst forming groups and may be due to disturbances in ovarian metabolism. Follicular rupture is important for efficient P release by the corpus luteum.     

Erythema dyschromicum perstans

A 29-year-old woman from Trinidad experienced the rapid onset of extensive lesions characteristic of erythema dyschromicum perstans following an x-ray study using orally administered contrast. Eleven months later a skin biopsy specimen showed few epidermal changes but extensive incontinence of melanin pigment and marked dilatation of lymphatics in the superficial dermis. Results of a systemic evaluation were normal. The available data on this disease are analyzed and conclusions offered regarding its nature and causes.