The value of image-guided intensity-modulated radiotherapy in challenging clinical settings.

OBJECTIVE: To illustrate the wider potential scope of image-guided intensity-modulated radiotherapy (IG-IMRT), outside of the "standard" indications for IMRT. METHODS: Nine challenging clinical cases were selected. All were treated with radical intent, although it was accepted that in several of the cases the probability of cure was low. IMRT alone was not adequate owing to the close proximity of the target to organs at risk, the risk of geographical miss, or the need to tighten planning margins, making image-guided radiotherapy an essential integral part of the treatment. Discrepancies between the initial planning scan and the daily on-treatment megavoltage CT were recorded for each case. The three-dimensional displacement was compared with the margin used to create the planning target volume (PTV). RESULTS: All but one patient achieved local control. Three patients developed metastatic disease but benefited from good local palliation; two have since died. A further patient died of an unrelated condition. Four patients are alive and well. Toxicity was low in all cases. Without daily image guidance, the PTV margin would have been insufficient to ensure complete coverage in 49% of fractions. It was inadequate by >3 mm in 19% of fractions, and by >5 mm in 9%. CONCLUSION: IG-IMRT ensures accurate dose delivery to treat the target and avoid critical structures, acting as daily quality assurance for the delivery of complex IMRT plans. These patients could not have been adequately treated without image guidance. ADVANCES IN KNOWLEDGE: IG-IMRT can offer improved outcomes in less common clinical situations, where conventional techniques would provide suboptimal treatment.

Impact of 18F-fluorodeoxyglucose positron emission tomography in the staging and treatment response assessment of extra-pulmonary small-cell cancer.

The aim of this study was to retrospectively evaluate the value of (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in extrapulmonary small-cell cancer (EPSCC). Patients with EPSCC who underwent PET for staging or response assessment between 1996 and 2007 were identified from a database. Patient records were reviewed. PET-based, and conventional staging and restaging results were compared. The binary staging classification of limited disease (LD) versus extensive disease (ED) was used. Patients with LD had tumours that could be encompassed within a tolerable radiation therapy (RT) volume. Of 33 eligible patients, 12 had staging PET scans, 11 had restaging scans and 10 had both. All known gross disease sites were FDG-avid. PET and conventional stage groupings were concordant in 21 of 22 cases. One patient was appropriately upstaged from LD to ED by PET. PET detected additional disease sites, without causing upstaging in three further patients. Restaging PET scans identified previously unrecognised persistent or progressive disease in 4 of 21 cases. In four further cases, persistent FDG uptake after treatment was either false positive (n = 2) or of uncertain (n = 2) aetiology. PPV was 100% for staging and 82% for restaging. In 8 of 43 imaging episodes (19%), PET appropriately influenced management in five cases by changing treatment intent from radical to palliative, and in three cases by altering the RT volume. PET has incremental value compared to conventional imaging for staging EPSCC, and may also be useful for restaging after therapy. PET influenced patient management in 19% of 43 imaging episodes.

Acute visual loss induced by dexamethasone during neoadjuvant docetaxol.

We present a case of a female patient who developed acute onset of visual loss due to central serous retinopathy as a consequence of steroid premedication for docetaxol given as second line neoadjuvant chemotherapy for breast cancer. Central serous retinopathy is a recognised association with steroids but has not been previously reported in association with the management of solid tumours. Reduction in steroid dose and duration permitted recovery of her visual acuity while allowing completion of the prescribed chemotherapy regimen. An overview of the presentation, pathogenesis, aetiologies and management of central serous retinopathy is given.

Harvest protocol to reduce variability of soluble enzyme yield from cultured cells.

Many aspects of physiology and gene regulation can be studied by examining the levels of enzymes harvested from cultured cells. We found that the yield from cultured cells of two different cytosolic enzymes, creatine kinase and the common reporter gene product chloramphenicol acetyltransferase (CAT), could be highly variable despite superficially identical harvest procedures. Analysis of multiple harvest and assay parameters disclosed that fluctuations in enzyme yield were correlated with the time cells that were allowed to remain in an EDTA-containing buffered saline solution prior to scraping from the dishes with a rubber policeman. The highest and most consistent yields were obtained when the cells were allowed to remain in the solution for 6-10 min before scraping: this protocol has cut variability approximately by a factor of three.

Clinical relevance of a dipole field in rolandic spikes.

The clinical presentation of 366 children with rolandic spikes was examined to determine whether the presence of a temporal-frontal dipole field is associated with a lower incidence of clinical abnormality. Comparisons were made between the clinical presentation of 99 children with temporal-frontal dipole discharges versus 267 children with nondipole rolandic discharges. Criteria examined were birth history, developmental milestones, school history, total number of seizures, neurological examination, and computed tomography (CT) findings. For all clinical parameters, except birth history and CT finding, there was a lower incidence of clinical abnormality in the group with dipole discharges (p less than 0.001). The clinical profile seen with temporal-frontal dipole discharges was very different than with nondipole rolandic spikes. Children with dipole discharges less often presented with frequent seizures (10%), developmental delay (18%), school difficulties (34%), or abnormal neurological exam (22%). In contrast, children with nondipole rolandic discharges often presented with a history of frequent seizures (55%), developmental delay (55%), school difficulties (60%), and an abnormal neurological exam (63%). The incidence of clinical abnormalities in the nondipole group exceeded that found in our control population in all areas. Temporal-frontal dipole discharges are associated with a lower incidence of clinical abnormality than are nondipole rolandic spikes. These discharges may represent a benign functional focus.

A double-blind amino acids, L-tryptophan and L-tyrosine, and placebo study with cocaine-dependent subjects in an inpatient chemical dependency treatment center.

In a six-month double-blind study in an inpatient chemical dependency facility, 29 cocaine-dependent subjects were studied to determine if the amino acids, L-tryptophan and L-tyrosine, would decrease cocaine craving and withdrawal symptoms. Those subjects receiving placebo were shown to have a statistically significant increase in only one physical symptom category. The drug craving and other major physical and subjective symptoms were not shown to be significant. This study is consistent with a literature review in demonstrating that the amino acids do not significantly reduce most symptoms of cocaine craving and withdrawal when used alone.

Topographical analysis of the centrotemporal discharges in benign rolandic epilepsy of childhood.

The onset, distribution, and spread of the average of 20 centrotemporal discharges for each of 10 patients with typical benign rolandic epilepsy of childhood (BREC) were examined using a computerized topographical mapping technique. A stereotypic dipole field was present along the rolandic region in all discharges. During its most prominent phase, the negative pole of the dipole was maximum at the centrotemporal region, with the positive pole involving the bifrontal region. A hypothesis is proposed that all discharges arise from a single generator which is oriented tangential to the surface. The generator is most likely situated in the lower rolandic region where the zero potential zone exists, between the frontal positivity and the centrotemporal negativity. Identification of this dipole configuration may be useful for differentiating BREC from focal epilepsy of other etiologies.