An isotoxic planning comparison study for stage II-III non-small cell lung cancer: is intensity-modulated radiotherapy the answer?

AIMS

Recent clinical series suggest that treating patients with isotoxic twice-daily radiotherapy may be beneficial. This dosimetric planning study compared the use of intensity-modulated radiotherapy (IMRT) and three-dimensional conformal radiotherapy (3DRT) to deliver isotoxic treatment for non-small cell lung cancer (NSCLC) patients.

MATERIALS AND METHODS

Twenty patients with stage II/III NSCLC were selected. A dose-escalated plan was produced retrospectively for each using three different methods: (i) three to five beams 3DRT; (ii) seven beams inverse-planned conformal radiotherapy; (iii) seven beams IMRT. The starting point for dose escalation was 55.8 Gy in 1.8 Gy per fraction twice-daily. The number of fractions was then increased until one or more organ at risk tolerance dose was exceeded or a maximum dose of 79.2 Gy was reached.

RESULTS

The median escalated doses were 70.2, 66.6 and 64.8 Gy for IMRT, 3DRT and inverse-planned conformal radiotherapy, respectively. IMRT allowed a significant dose increase in comparison with the other two methods (P < 0.05), whereas no significant difference was found between 3DRT and inverse-planned conformal radiotherapy. IMRT was more successful at escalating dose in patients where the brachial plexus and spinal canal were close to the planning target volume. IMRT did not allow the escalation of dose beyond 70.2 Gy (82.8 Gy BED10, 69 Gy EQD2) due to the proximity of disease to the great vessels and the proximal bronchial tree.

CONCLUSIONS

IMRT allows increased dose escalation compared with conformal radiotherapy. However, there is limited opportunity to escalate the prescription dose beyond 70.2 Gy twice-daily in disease close to the central mediastinal structures.

Psychiatric functioning and quality of life in young patients with cardiac rhythm devices

BACKGROUND

Less is known about depression, anxiety and quality of life (QoL) in children and adolescents with pacemakers (PMs) and implantable cardioverter-defibrillators (ICDs) than is known in adults with these devices.

METHODS

A standardized psychiatric interview diagnosed anxiety/depressive disorders in a cross-sectional study. Self-report measures of anxiety, depression and post-traumatic stress disorder were obtained. Medical disease severity, family functioning and QoL data were collected. A total of 166 patients were enrolled (52 ICD, 114 PM; median age 15 years).

RESULTS

Prevalence of current and lifetime psychiatric disorders was higher in patients with ICDs than PMs (Current: 27% vs. 11%, P = .02; Lifetime: 52% ICD vs. 34% PM, P = .01). Patients with ICDs had more anxiety than a healthy population (25% vs. 7%, P < .01). Patients with ICDs and PMs had similar levels of depression as a healthy population (ICD 10%, PM 4%, reference 4%, P = .29). In multivariate analysis including a medical disease score, demographics, exposure to beta-blockers, activity limitations, hospitalizations, shocks and procedures, the type of device (PM versus ICD) did not predict psychiatric diagnoses when age at implantation and the severity of medical disease were controlled for. Patients with ICDs and PMs had lower physical QoL scores (ICD 45, PM 47.5, Norm 53, P ≤ .03), but similar psychosocial functioning scores (ICD 49, PM 51, Norm 51, P ≥ .16) versus a normal reference population.

CONCLUSIONS

Anxiety is highly prevalent in young patients with ICDs, but the higher rates can be attributed to medical disease severity and age at implantation instead of type of device.

Which bowel preparation is best? Comparison of a high-fibre diet leaflet, daily microenema and no preparation in prostate cancer patients treated with radical radiotherapy to assess the effect on planned target volume shifts due to rectal distension

OBJECTIVE

We evaluated and compared a high-fibre diet leaflet, daily microenema and no preparation to establish how best to achieve consistent bowel preparation in prostate cancer patients being treated with radical radiotherapy.

METHODS

3 cohorts of 10 patients had different dietary interventions: no bowel preparation, high-fibre diet information leaflet and daily microenemas. The available cone beam CT (CBCT) scans of each patient were used to quantify interfractional changes in rectal distension (measured using average cross-sectional area-CSA), prostate shifts relative to bony anatomy compared with that at CT planning scan and rates of geometric miss (i.e. shifts of ≥5 mm). 85 CBCT scans were available in the pre-leaflet cohort, 89 scans in the post-leaflet, and 89 scans in the post-enema group.

RESULTS

Mean rectal CSA in the post-enema group was reduced compared with both pre-leaflet (p=0.010) and post-leaflet values (p=0.031). The magnitude of observed mean prostate shifts was significantly reduced in the post-enema group compared with the pre-leaflet group (p=0.014). The proportion of scans showing geometric miss (i.e. shift >5 mm) in the post-enema group (31%) was significantly lower than in the pre-leaflet (62%, p<0.001) or post-leaflet groups (56%, p<0.001).

CONCLUSION

This study indicates microenema to be an effective measure to achieve reduction in rectal CSA, prostate shift and reduce geometric miss of ≥5 mm. A further prospective randomised study is advocated to validate the results.

ADVANCES IN KNOWLEDGE

The use of microenema is effective in reducing prostate shift and rectal CSA, consequently decreasing the incidence of geographical miss.

The Multicenter Pediatric and Adult Congenital EP Quality (MAP-IT) Initiative-rationale and design: report from the pediatric and congenital electrophysiology society's MAP-IT taskforce

Multicenter clinical registries are increasingly recognized as valuable tools for establishing benchmarks, facilitating patient-centered quality improvement and research. In 2010, the Pediatric and Congenital Electrophysiology Society convened a taskforce of its members to design, construct, and implement a clinical registry known as the Multicenter Pediatric and Adult Congenital EP Quality (MAP-IT) Initiative. The present aim of the MAP-IT Initiative is to create an infrastructure by which we can measurably improve patient-centered outcomes and reduce complications associated with electrophysiology studies and catheter ablation in pediatric and congenital heart disease patients. The purpose of this writing is to report the progress to date from three of the four subcommittees of the MAP-IT taskforce. Specifically, we present our initial set of key data elements and definitions, recommended database table structure, and considerations regarding wide-scale implementation of the registry. Development of a risk/complexity score for use in the MAP-IT registry is presented in a separate companion manuscript. It is our intent that these manuscripts will serve to introduce the electrophysiology and pediatric cardiology community to the MAP-IT initiative and provide a rationale for its design and recommended implementation strategy.

Guns, germs, and stealing: exploring the link between infectious disease and crime

Can variation in crime rates be traced to the threat of infectious disease? Pathogens pose an ongoing challenge to survival, leading humans to adapt defenses to manage this threat. In addition to the biological immune system, humans have psychological and behavioral responses designed to protect against disease. Under persistent disease threat, xenophobia increases and people constrict social interactions to known in-group members. Though these responses reduce disease transmission, they can generate favorable crime conditions in two ways. First, xenophobia reduces inhibitions against harming and exploiting out-group members. Second, segregation into in-group factions erodes people's concern for the welfare of their community and weakens the collective ability to prevent crime. The present study examined the effects of infection incidence on crime rates across the United States. Infection rates predicted violent and property crime more strongly than other crime covariates. Infections also predicted homicides against strangers but not family or acquaintances, supporting the hypothesis that in-group-out-group discrimination was responsible for the infections-crime link. Overall, the results add to evidence that disease threat shapes interpersonal behavior and structural characteristics of groups.

Prospective evaluation of defibrillation threshold and postshock rhythm in young ICD recipients

BACKGROUND

Adaptation of implantable cardioverter defibrillator (ICD) systems to the needs of pediatric and congenital heart patients is problematic due to constraints of vascular and thoracic anatomy. An improved understanding of the defibrillation energy and postshock pacing requirements in such patients may help direct more tailored ICD therapy. We describe the first prospective evaluation of defibrillation threshold (DFT) and postshock rhythm in this population.

METHODS

We prospectively studied patients ≤ 60 kg at time of ICD intervention. DFTs were obtained using a binary search protocol with three VF inductions. Postshock pacing was programmed using a stepwise protocol, lowering the rate prior to each VF induction.

RESULTS

Twenty patients were enrolled: 11 had channelopathy, five congenital heart disease, and four cardiomyopathy. The median age was 16 years, median weight 48 kg. Twelve patients had a transvenous high-voltage coil; eight had pericardial +/- subcutaneous coil(s). Median DFT was 7 J (range 3-31 J); 19/20 patients had DFT ≤ 15 J and all patients <25 kg had DFT ≤ 9 J (n = 6). There was no difference in DFT between patients with transvenous versus pericardial +/- subcutaneous coils (median 7 J vs 6 J, P = 0.59). No patient with normal atrioventricular conduction prior to defibrillation required postshock pacing (n = 16). There were no adverse events.

CONCLUSIONS

These data suggest that many pediatric ICD patients have low DFTs and adequate postshock escape rhythm. This may help determine appropriate parameters for future design of pediatric-specific ICDs.

What about us? Children's experiences of living with a sibling with spinal cord injury

Spinal cord injury is a life transforming condition that is thought to have an impact on the entire family of the affected individual. The needs and psychological outcomes of siblings of children with spinal cord injury (SCI) have not been researched. The current study focuses on the experiences of children living with a brother or sister with SCI. Eight participants (4 male, 4 female) aged between 7 and 18 years were interviewed using a semi-structured interview, concentrating on their unique experiences and understandings of having a brother or sister with SCI. The qualitative method of Interpretative Phenomenological Analysis (IPA) was used to analyze the data and three main themes were identified: "Life interrupted", "What about me?" and "My safety net". Results are discussed in relation to attachment and coping and adjustment theories. The discussion also highlights the clinical implications for siblings and parents of children affected by SCI, and for professionals who work within pediatric SCI settings.