Pushing the envelope beyond a centimeter in rectal cancer: Oncologic implications of close but negative margins

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Background: Advances in surgery, adjuvant therapy and understanding of the natural history of rectal cancer has enabled sphincter preservation surgery for most patients. A 1 cm margin is commonly accepted as minimal distal margin, when not achievable many are relegated to permanent colostomy. Our purpose was to determine if distal margins of < 1 cm is justified by the world's published experience.

Methods: Studies were identified with a MEDLINE search using terms rectal cancer, colorectal cancer, margins and distal margins with an additional manual search. There were no restrictions on data type or year of publication. All studies were retrospective or prospective, none were randomized controlled. Studies were excluded if specific margins, local recurrence rates or case level data could not be extracted. Extracted variables included year of publication, time span, number of patients, standardized surgery, radiotherapy, margins, follow up, local recurrence rates and overall survival. Meta-analysis was performed using a random weighting scheme. Values were aggregated across studies to determine overall impact and p-values.

Results: Seventeen studies reported margins with thirteen studies, 3,232 patients, reporting outcomes when < 1cm. Meta-analysis of all studies indicated a nonsignificant trend favoring greater margins. However, in order to understand distal margins in the context of current standards additional analyses were performed. Of the thirteen studies 4 reported neither TME nor use adjuvant radiotherapy and 9 studies reported use of one or both. When either total mesorectal excision and/or adjuvant radiotherapy was reported there was no significant increase in local recurrence with distal margins < 1 cm. In studies that used neither therapy > 1 cm margins were statistically less prone to recurrence.

Conclusions: Sphincter preservation is possible with < 1 cm distal margin when optimal surgical and adjuvant therapy are applied.

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A pilot bridging data integration and analytics: BioMediator and R?

Biological research today involves aggregating and analyzing large amounts of data from disparate sources. Tools such as the University of Washington's BioMediator system integrate heterogeneous data. Analytic packages such as the R environment have a rich set of tools to analyze biomedical research data. Our pilot project bridged data integration and analytics in a general way by successfully incorporating the BioMediator system into the R platform for specific analyses on neurophysiologic research data.

Cellular kinetics of murine lung: model system to determine basis for radioprotection with keratinocyte growth factor

PURPOSE

Normal tissue toxicity remains a dose limitation for cancer radiotherapy and chemoradiotherapy. Growth factors offer a novel means of mitigating normal tissue radiotoxicity. In particular, keratinocyte growth factor (rHuKGF), whose proliferative activity is restricted to epithelial cells, holds promise on the basis of the findings of preclinical models of epithelial cytoprotection and the clinical developments to date. We report the radioprotection of murine lung by an increase in tissue cellularity after rHuKGF-induced proliferation.

METHODS AND MATERIALS

Flow cytometric and image analysis techniques after bromodeoxyuridine labeling were used to estimate proliferative parameters. Our specialized analytical methods measure not only labeling indexes, but also the durations of S and G(2)+M phases, potential doubling times, and the net cell production rate. Image analysis techniques were used to identify the specific cell types that were proliferating (type II pneumocytes).

RESULTS

Lung labeling index control values (0.5%) rose to a maximum (5.5%) at 3 days after intratracheal rHuKGF, returning to normal by Day 7. The potential doubling time fell from 66 days to 4.4 days. The net cell production rate rose from a control value of 1%/d to >15%/d by Day 3. This resulted in a nearly twofold increase in alveolar epithelial cellularity, which remained significantly elevated on Day 7. Saline-treated control animals exhibited no significant changes in the proliferative parameter values or cellularity. On the basis of these data, mice were irradiated, solely to the thorax, with ranges of single doses of 250 kVp X-rays 7 days after either intratracheal administration of 5 mg/kg rHuKGF or phospate-buffered saline. This interval was chosen because the proliferative response of the type II cells was finished but the cellularity of the lung remained increased. Pretreatment with rHuKGF extended the latent period before onset of pneumonitis after all radiation doses. rHuKGF treatment 7 days before thoracic irradiation significantly protected against pneumonitis (median effective dose 13.7 Gy, 95% confidence limit 13.4-14.0) compared with the control pretreatment with phosphate-buffered saline (median effective dose 12.8 Gy, 95% confidence limit 12.6-13.1).

CONCLUSION

The data showed that an increase in tissue cellularity, caused by rHuKGF treatment before irradiation, protected the lung from damage due to pneumonitis.

Functional roles of Broca's area and SMG: evidence from cortical stimulation mapping in a deaf signer

The importance of the left hemisphere in language function has been firmly established and current work strives to understand regional specializations within the perisylvian language areas. This paper reports a case study of a deaf user of American Sign Language undergoing an awake cortical stimulation mapping procedure. Patterns of sign errors accompanying electrical stimulation of Broca's area and the supramarginal gyrus (SMG) are reported. Our findings show Broca's area to be involved in the motor execution of sign language. These data demonstrate that the linguistic specificity of Broca's area is not limited to speech behavior. In addition, unusual semantic-phonological errors were observed with stimulation to the SMG; these data may implicate the SMG in the binding of linguistic features in the service of language production. Taken together, these findings provide important insight into the linguistic specificity of Broca's area and the functional role of the supramarginal gyrus in language processing.

Visualization-based mapping of language function in the brain

Cortical language maps, obtained through intraoperative electrical stimulation studies, provide a rich source of information for research on language organization. Previous studies have shown interesting correlations between the distribution of essential language sites and such behavioral indicators as verbal IQ and have provided suggestive evidence for regarding human language cortex as an organization of multiple distributed systems. Noninvasive studies using ECoG, PET, and functional MR lend support to this model; however, there as yet are no studies that integrate these two forms of information. In this paper we describe a method for mapping the stimulation data onto a 3-D MRI-based neuroanatomic model of the individual patient. The mapping is done by comparing an intraoperative photograph of the exposed cortical surface with a computer-based MR visualization of the surface, interactively indicating corresponding stimulation sites, and recording 3-D MR machine coordinates of the indicated sites. Repeatability studies were performed to validate the accuracy of the mapping technique. Six observers-a neurosurgeon, a radiologist, and four computer scientists, independently mapped 218 stimulation sites from 12 patients. The mean distance of a mapping from the mean location of each site was 2.07 mm, with a standard deviation of 1.5 mm, or within 5.07 mm with 95% confidence. Since the surgical sites are accurate within approximately 1 cm, these results show that the visualization-based approach is accurate within the limits of the stimulation maps. When incorporated within the kind of information system envisioned by the Human Brain Project, this anatomically based method will not only provide a key link between noninvasive and invasive approaches to understanding language organization, but will also provide the basis for studying the relationship between language function and anatomical variability.

Adult attention-deficit hyperactivity disorder: assessment guidelines based on clinical presentation to a specialty clinic

Of 143 adults presenting for attention-deficit hyperactivity disorder (ADHD) evaluation, 46 (32%) clearly met diagnostic criteria, 46 (32%) clearly did not meet diagnostic criteria, and another 51 (36%) with current ADHD-like features did not meet criteria due to either a lack of childhood history and/or complicating severe psychiatric or substance abuse comorbidity. The three groups were similar in demographics, psychiatric diagnosis, psychiatric symptom severity, and functional impairment. Compared with the group not meeting ADHD criteria, patients with ADHD had more frequent histories of learning disability in childhood, poorer reading scores on the Wide-Range Achievement Test (WRAT), poorer scores on the Continuous Performance Test (CPT), and higher scores on the Wender-Utah Rating Scale (WURS) for ADHD. Patients in the ambiguous ADHD category had higher rates of current substance abuse than the other two groups. While this group resembled the non-ADHD group in having a low incidence of learning disability and normal reading scores, their poor performance on the CPT and high scores on the WURS more closely resembled those of ADHD patients. These findings suggest that there are a few rating scales, testing instruments, and lifetime history characteristics that help to clarify the difficult diagnostic distinction between adult patients who do and do not have ADHD.

Evaluation of a visualization-based approach to functional brain mapping

We describe a method for mapping stimulation data, obtained at the time of neurosurgery for intractable epilepsy, onto a 3D MRI-based neuroanatomic model of the individual patient. The mapping is done by comparing an intraoperative photograph of the exposed cortical surface with a computer-based MR visualization of the surface, interactively indicating corresponding stimulation sites, and recording 3-D MR machine coordinates of the indicated sites. Repeatability studies were performed to validate the accuracy of the mapping technique. Six observers--a neurosurgeon, a radiologist, and four computer scientists, independently mapped 218 stimulation sites from 12 patients. The mean distance of the six locations from the mean location of each site was 2.07 mm, with a standard deviation of 1.5 mm, or within 5.07 mm with 95% confidence. Since the surgical sites are accurate within approximately 1 cm, these results show that the visualization-based approach is accurate within the limits of the stimulation maps. When incorporated within the kind of information system envisioned by the Human Brain Project, this anatomically-based method will not only provide a key link between non-invasive and invasive approaches to understanding language organization, but will also provide the basis for studying the relationship between language function and anatomical variability.

A psychiatrist-rated battery of measures for assessing the clinical status of psychiatric inpatients

Despite the increasing demand for outcome assessment measures, no published reports have provided a standardized way to assess psychiatric inpatients that includes diagnosis and observer ratings of psychopathology. This paper reviews general principles for selecting outcome assessment measures, proposes a battery of instruments based on already available measures to assess clinical status in psychiatric inpatients, reviews methods of implementing the battery in an academic inpatient psychiatric setting, and presents preliminary data on its interrater reliability, construct validity, and range of response to acute hospitalization. Preliminary results suggest that the battery may be useful for resident and medical student education and for enhancing quality assurance and continuous quality improvement.

Percutaneous cardiopulmonary bypass to support angioplasty and valvuloplasty. Technical considerations

To eliminate problems during percutaneous transluminal coronary angioplasties (PTCAs) or valvuloplasties (PV), percutaneous cardiopulmonary bypass (PCPB) was used in 19 high-risk patients (pts) to perform supported PTCA (12 pts, age 40-68) for low EF and/or a large area of risk (L main), and supported PV (7 pts, age 68-92) for "nonoperative" candidates with severe AS. Our experience promoted a review of the technical aspects of PCPB was needed for a successful outcome in these high-risk patients. All patients were treated with IV amnestics while awake in the catheter laboratory. Early in the experience, 20F arterial and venous cannulas were inserted via a 2 cm cutdown in the right groin; now 17F arterial and 20F venous cannulas are placed via a Seldinger technique using fluoroscopy. Traversement of the iliac vein is enhanced by a roll under the buttocks. If the artery is calcified, a cutdown, vessel loops, and direct repair are employed to assure post-PCPB patency. Total flows of 6L/min are easily achieved with nonreservoir centrifugal pump bypass. If flow or pressures fall, 200 cc of blood or crystalloid rapidly improves venous drainage and flows and unlike during reservoir bypass, alpha agonists are only rarely necessary; CaCl often produces nausea in these patients. PCWP's are brought to 0-5 mm Hg. Due to the 1,500 cc priming volume, on-pump transfusion is often required. Two patients were successfully transported to the OR on PCPB for treatment of catheter failures. With attention to technical details, percutaneous bypass supported PTCA or PV is an important new therapy for high risk patients.

Congenital toxoplasmosis presenting as isolated acute chorioretinitis in the neonate

We describe a neonate with congenital ocular toxoplasmosis that presented as isolated, acute bilateral retinochoroiditis. Although toxoplasmic retinochoroiditis is not rare, it is quite unusual to diagnose congenital toxoplasmosis based on isolated bilateral retinochoroiditis in an otherwise healthy neonate. Bilateral retinochoroiditis can be caused by syphilis, herpes virus, cytomegalovirus, and toxoplasmosis. Because specific treatments now exist for these conditions, it is important to establish proper diagnosis so that treatment can be initiated promptly. The differential diagnosis, work-up, and management of retinochoroiditis in the newborn is presented and discussed.

XXII. Results of the application of Captain Kater's floating collimator to the astronomical circle at the observatory of Trinity College, Dublin, and remarks relative to those results

The results of the observations which I am about to state will, I think, be considered as affording a strong testimony of the importance of the floating collimator. As applied to my circle, it furnishes the means of ascertaining the index correction with as great precision as by reversion, and in several points of view is undoubtedly superior to that method. The reversing principle of the Dublin circle serves very conveniently for a measure of the accuracy of the floating collimator, and appears to show satisfactorily, that in the application of this instrument to any circle, no error belonging to the instrument will be introduced into the results; or in other words, that the results obtained by the assistance of the collimator, will not be sensibly affected by errors introduced by the collimator itself.