Correlation of hot spot to breast separation in patients treated with postlumpectomy tangent 3D-CRT using field-in-field technique and mixed photon energies.

Radiotherapy to an intact breast was previously determined to have a positive correlation between breast separation measurement and hot spot dose. As breast separation measurement increased, hot spot dose increased. The purpose of this retrospective study was to determine if this correlation persisted despite current techniques including field-in-field (FiF) blocking and mixed photon energies. Radiation treatment plans on unilateral intact breasts from 90 female, early stage breast cancer patients treated with lumpectomy were analyzed. Plans were created using 3-dimensional conformal radiation therapy (3D-CRT) nondivergent opposing tangent beams, FiF technique, and 6 MV with or without higher energy photons. Data collected included breast separation measurement, hot spot point dose and location, number of beams, photon energy, clinical target volume (CTV) coverage and breast volume coverage. Correlations between breast separation measurement and each of these values were determined. The positive correlation between breast separation measurement and hot spot dose persisted despite incorporating FiF and mixed photon energies. Correlations were also found between breast separation and the number of beams as well as breast separation and photon energy. Larger breast separations tended to be treated with additional beams of higher photon energy. There were no correlations found between breast separation and CTV or breast volume coverage. The data in this study suggested the medical dosimetrist should expect hot spots above prescription dose of 106%, 107%, and 108% for small, medium and large breast separation sizes respectively. Additionally, adding a high energy photon bean may be indicated with medium and large breast separations.

Retrospective survey of owners' experiences with palliative radiation therapy for pets.

OBJECTIVE To describe animal owners' experiences with palliative radiation therapy (PRT) of pets and identify factors influencing satisfaction with their pets' treatment. DESIGN Retrospective, cross-sectional study. SAMPLE 118 owners of dogs, cats, or rabbits. PROCEDURES Medical records were searched to identify animals that underwent PRT between 2004 and 2013. Signalment, tumor-related data, and outcome information were recorded. Owners completed an electronic survey assessing satisfaction with treatment (ie, satisfaction with the decision for their pet to undergo PRT and indication that they would choose PRT for their pet again), expectations regarding PRT, and perceptions of their pets' quality of life (QOL) and signs of discomfort from acute adverse radiation effects. Additional data regarding practical aspects of treatment, pet death, communications with veterinarians, and owner demographics were collected. Variables were tested for association with measures of owner satisfaction. RESULTS 92 of 116 (79%) owners were satisfied with the decision to have their pets undergo PRT. Most (92/118 [78%]) owners reported their pet's QOL improved after PRT; these owners were significantly more likely to be satisfied than those who did not report improved QOL. Owners who perceived their pets had discomfort from adverse radiation effects (38/116 [33%]) were significantly less likely to be satisfied than owners who did not report this observation. Measures of satisfaction were not associated with patient survival time. Twenty-one of 118 (18%) owners indicated they expected PRT would cure their pet's tumor. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that short life expectancy should not deter recommendation of PRT for pets. Protocols that minimize risk of acute adverse effects may be advantageous. Veterinarians should attempt to ensure that owners understand the goals of PRT.

A 3-month safety and efficacy study of travoprost 0.004% ophthalmic solution compared with timolol in pediatric patients with glaucoma or ocular hypertension.

PURPOSE: To evaluate efficacy and safety of travoprost in pediatric patients with ocular hypertension or glaucoma and demonstrate its noninferiority to timolol. METHODS: Patients aged 2 months to <18 years with glaucoma or ocular hypertension were randomized to receive travoprost (0.004%) or timolol eye drops (0.25% for patients aged 2 months to <3 years and 0.5% for patients ≥3 years old) for 3 months in this double-masked, parallel-group study. Intraocular pressure (IOP) was measured and patients were evaluated at 2 weeks, 6 weeks, and 3 months after treatment. Change in IOP from baseline to 3 months was the primary endpoint, and the test of noninferiority was based on a margin of +3.0 mm Hg using the 95% 2-sided confidence interval of the mean change. RESULTS: Of 157 patients included (mean age, 9.6 years), 77 received travoprost and 75 timolol. All patients experienced a significant reduction in IOP in the study eye at 3 months: the mean IOP change from baseline was -5.4 mm Hg for travoprost; -5.3 mm Hg, for timolol. The mean difference between travoprost and timolol at month 3 was -0.1 mm Hg (95% CI, -1.5 to 1.4 mm Hg). The most common treatment-related adverse events for the travoprost group were ocular hyperemia and eyelash growth. No serious adverse events were reported. CONCLUSIONS: This study found travoprost to be noninferior to timolol in lowering IOP in patients with pediatric glaucoma or ocular hypertension. Travoprost was well-tolerated, and no treatment-related systemic adverse events were reported.

Validation of companion diagnostic for detection of mutations in codons 12 and 13 of the KRAS gene in patients with metastatic colorectal cancer: analysis of the NCIC CTG CO.17 trial.

CONTEXT: The therascreen KRAS RGQ polymerase chain reaction kit is being developed as a companion diagnostic to aid clinicians, through detection of KRAS mutations, in the identification of patients with metastatic colorectal cancer (mCRC) who are more likely to benefit from cetuximab. OBJECTIVES: To assess whether KRAS mutation status, determined by using the therascreen KRAS kit, is a predictive marker of cetuximab efficacy. DESIGN: Tissue samples were obtained from patients with mCRC treated on the National Cancer Institute of Canada Clinical Trials Group (NCIC CTG) CO.17 phase 3 study of cetuximab plus best supportive care (BSC) versus BSC alone. Tumor DNA samples were assessed for the presence of KRAS mutations by using the therascreen KRAS kit. Efficacy and safety were assessed to determine whether mutation status was predictive of outcomes. Results.-Evaluable samples were available from 453 patients (79.2%) enrolled in the NCIC CTG CO.17 trial. The KRAS wild-type subset represented 54.1% (245 of 453) of the evaluated population. Median overall survival of patients with KRAS wild-type tumors was 8.6 months among those who received cetuximab plus BSC and 5.0 months among patients who received BSC alone (hazard ratio [HR], 0.63; P = .002). Among patients with KRAS mutant mCRC, no meaningful difference in overall survival was observed between arms (HR, 0.91; P = .55). These results are consistent with a previous report that analyzed patient tumor samples by using bidirectional sequencing. CONCLUSIONS: These data support the utility of the therascreen KRAS kit as a means of selecting patients who may benefit from cetuximab therapy.