Medication of Diseases News - Part 10

Extracranial Stereotactic Radioablation: Dose-Limiting Toxicity

Treatment planning was conducted (RenderPlan 3-D planning system; Elekta Oncology), and a total of seven noncoplanar, nonopposing beams were used to deliver a dose to the PTV for each patient. The beam apertures were drawn to just encompass the PTV defined above (ie, no margin). Forward-planning intensity modulation was used to create parabolic dose profiles across each beam in an effort to deliver higher central tumor dose in regions of hypoxia with steeper falloff gradients to normal tissue. Beam intensities were manipulated to deliver roughly equal absolute dose to the isocenter from each beam. In all cases, 95% of the PTV was covered by the 80% prescription isodose volume. Hot spots (ie, > 80% isodose) occurred solely within the GTV. Beam angles were directed to ensure that no point along the spinal cord received > 600 cGy in a single treatment. The intensity modulation was achieved by milling beam attenuation compensators for each field. Carefully cut and verified focus blocks for each field were created to custom shape the fields at treatment. there

Extracranial Stereotactic Radioablation: Immobilization, Targeting, and Dosimetry

Extracranial Stereotactic Radioablation: Immobilization, Targeting, and DosimetryAll patients were immobilized in a stereotactic body frame (Elekta Oncology; Norcross, GA) that employs a rigid frame and vacuum pillow to make a large contact surface area on three sides of the patient. The immobilization system includes an abdominal compression device that limits the ability of the patient’s diaphragm to move caudally, thereby limiting the respiratory motion of the target. Patients are repositioned in this system using two tattoo marks on the sternum and bilateral tibial tattoo marks that are all referenced to the frame. The accuracy and reproducibility of this specific frame system and other similar frames has been described in previous reports. fully

Extracranial Stereotactic Radioablation: Pretreatment Assessment and Follow-up Studies

A history of previous lung RT or mediastinal RT excluded patients from the trial. It was required that there be no plans for further concomitant or adjuvant antineoplastic therapy (including chemotherapy or fractionated RT) while on the protocol except at disease progression. Patients with active systemic, pulmonary, or pericardial infection were not eligible. Pregnant or lactating women were not eligible. Patients were required to be at least 18 years old and have a Karnofsky performance status of > 60 in order to be enrolled into the trial.
The following evaluations were performed prior to treatment, at 4 to 6 weeks post treatment, and every 3 months thereafter: (1) physical examination; (2) weight and performance status assessment; (3) pulmonary function testing, including measurement of arterial blood gases, spirometry, volumes, and diffusing capacity of the lung for carbon monoxide (Dlco); and (4) either chest radiograph (CXR) or CT scan of the chest and upper abdomen. this

Extracranial Stereotactic Radioablation: Patients and Methods

Extracranial Stereotactic Radioablation: Patients and MethodsEligibility
Prior to the enrollment of any patients, the protocol and consent form were reviewed and approved by the review boards of the Indiana University Medical Center and the Richard L. Roudebush Veterans Administration Medical Center. All patients were willing to and capable of providing informed consent to participate in the protocol. All patients were required to undergo appropriate staging studies, identifying them as American Joint Committee on Cancer stage I (ie, T1 or T2N0M0) primary lung carcinoma. Patients with T2 tumors were enrolled into the study only if the tumor had a maximum dimension of < 7 cm. A histologic confirmation of cancer, by either biopsy or cytology, was required. The following primary cancer types were eligible: squamous cell carcinoma, adenocarcinoma, large cell carcinoma, bronchioloalveolar cell carcinoma, or NSCLC (not otherwise specified). further

Extracranial Stereotactic Radioablation: ESR

Historically, RT fields for early-stage NSCLC encompassed the primary tumor and regional lymphatics in the ipsilateral hilum and mediastinum. This “prophylactic” treatment was based on the identified risk of occult nodal involvement from surgical series ranging up to 20%, and surgical data indicating better control with more extensive resec-tions. However, large RT fields are potentially poorly tolerated in this population of patients with limited pulmonary reserves. More recent retrospective experiences have demonstrated similar survival results with fields limited to the primary tumor or gross disease alone, compared to fields including prophylactic treatment to lymph node chains. In a report from the Netherlands, limited “postage-stamp” fields were treated using hypofrac-tionated RT (ie, 4,800 cGy in 400-cGy fractions) with reported 3-year overall and disease-specific survival rates of 42% and 76%, respectively. add comment

Extracranial Stereotactic Radioablation

Extracranial Stereotactic RadioablationSurgical resection of stage I (T1-T2N0) non-small ^ cell lung cancer (NSCLC) results in 5-year survival rates of approximately 60 to 70%, and remains the treatment of choice for this population. Unfortunately, some patients with early-stage NSCLC are unable to tolerate the rigors of surgery or the postoperative recovery period due to lack of adequate respiratory reserve, cardiac dysfunction, diabetes mellitus, vascular disease, general frailty, or other comorbidities.

Respiratory Inductance Plethysmography in Healthy 3- to 5-Year-Old Children: Conclusion

Respiratory Inductance Plethysmography in Healthy 3- to 5-Year-Old Children: ConclusionHowever, in the supine position with increased abdominal compliance, diaphragmatic contraction may cause more outward abdomen motion before the onset of outward RC motion and a weaker coupling of diaphragm contraction and RC expansion, leading to less synchronous thoracoabdominal motion. In addition, the increased RC compliance in the 3- to 5-year-old age group compared to adults would be expected to exaggerate this mechanism.
Our results stress the importance of controlling for testing position in any comparative study of thoracoabdominal motion under conditions of respiratory loading, of lung or chest wall disease, or for longitudinal measurement. The ease in performing RIP and the need for minimal patient cooperation may make it a useful adjunct to or replacement for other modes of respiratory function testing in preschool-age children. In order to show this, further studies will be necessary to assess the ability of RIP measurements to discriminate healthy patients from those with lung disease, and to provide accurate longitudinal measurements of lung function in children with and without lung disease. further

Respiratory Inductance Plethysmography in Healthy 3- to 5-Year-Old Children: Feasibility and Success

Although there are no published data on the feasibility and success of performing RIP measurements in 3- to 5-year-old children, there are such data published on spirometry. Eigen et al showed a success of 83% in naive 3- to 6-year-old children, but did not list the success relative to age. In 3- to 5-year-old children, Kanengiser and Dozor2 showed a feasibility of 90% and success (the ability to reproducibly produce FEV1 during a trial of spirometry) of 56% in performing spirometry. They also showed an improvement in success with age.2 The study by Crenese et al, however, showed a success of 49%, which did not change with age. The high feasibility (> 95%) and success (> 80%) in performing RIP measurements in 3- to 5-year-old children shows that RIP can be easily performed in this age group.

Respiratory Inductance Plethysmography in Healthy 3- to 5-Year-Old Children: Discussion

Respiratory Inductance Plethysmography in Healthy 3- to 5-Year-Old Children: DiscussionThe mean ± SEM LBI measured in the sitting position was 1.01 ± 0.01. The LBI was not recorded in the supine and standing positions since volume calibration was not repeated after each change in position and the LBI requires a volume calibration.
When the subjects were in the supine position, many had an inward motion of the RC at the beginning of inspiration (Figs 2, 3). There was outward motion of both the thorax and abdomen at the onset of inspiration in both the sitting and standing positions (Fig 2).
Figures 4-6 show the mean (± 2 SEM) for Ф, PhRTB, and Tptef/Te in the sitting, supine, and standing positions. The SAS Proc Mixed procedure (SAS Institute) was used for comparing Ф, PhRTB, Tptef/Te, and Ti/Ttot by position. Table 5 shows the results of post hoc analyses. The statistical significance for pairwise comparison was adjusted to p < 0.017 using the Bonferroni method. There were significant differences in Ф and PhRTB between the sitting and supine positions, and supine and standing positions, and for PhRTB between the sitting and standing positions (Table 5). Tptef/Te and Ti/Ttot were significantly higher in the supine position compared to the sitting or standing positions (Table 5). fully

Respiratory Inductance Plethysmography in Healthy 3- to 5-Year-Old Children: Statistical Analysis

To evaluate the ease of use of RIP, we evaluated the feasibility and success of the procedure related to age. The feasibility was defined as the willingness of a child to perform the testing. The success was defined as the ability of a child to perform the procedure well, by the criteria described above.
Data were examined and described using mean, median, SD, and range. The associations between position (sitting, supine, and standing) and Ф, LBI, PhRTB, Tptef/Te, and Ti/Ttot were examined using the mixed-effects model with an unstructured covariance matrix to account for the correlation between the repeated measurements obtained at each position within each subject. Post hoc analysis was performed to further examine differences between the three positions. The statistical significance for pairwise comparison was adjusted to 0.017 using the Bonferroni method. We performed a Pearson or Spearman correlation to examine the relationship between age, weight, height, and gender and Ф, LBI, PhRTB, Tptef/Te, and Ti/Ttot in each position. The data were analyzed using SAS version 8 (SAS Institute; Cary, NC).

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