KRAS mutation effects on the 2-[18F]FDG PET uptake of colorectal adenocarcinoma metastases in the liver.

BACKGROUND: Deriving individual tumor genomic characteristics from patient imaging analysis is desirable. We explore the predictive value of 2-[18F]FDG uptake with regard to the KRAS mutational status of colorectal adenocarcinoma liver metastases (CLM). METHODS: 2-[18F]FDG PET/CT images, surgical pathology and molecular diagnostic reports of 37 patients who underwent PET/CT-guided biopsy of CLM were reviewed under an IRB-approved retrospective research protocol. Sixty CLM in 39 interventional PET scans of the 37 patients were segmented using two different auto-segmentation tools implemented in different commercially available software packages. PET standard uptake values (SUV) were corrected for: (1) partial volume effect (PVE) using cold wall-corrected contrast recovery coefficients derived from phantom spheres with variable diameter and (2) variability of arterial tracer supply and variability of uptake time after injection until start of PET scan derived from the tumor-to-blood standard uptake ratio (SUR) approach. The correlations between the KRAS mutational status and the mean, peak and maximum SUV were investigated using Student's t test, Wilcoxon rank sum test with continuity correction, logistic regression and receiver operation characteristic (ROC) analysis. These correlation analyses were also performed for the ratios of the mean, peak and maximum tumor uptake to the mean blood activity concentration at the time of scan: SURMEAN, SURPEAK and SURMAX, respectively. RESULTS: Fifteen patients harbored KRAS missense mutations (KRAS+), while another 3 harbored KRAS gene amplification. For 31 lesions, the mutational status was derived from the PET/CT-guided biopsy. The Student's t test p values for separating KRAS mutant cases decreased after applying PVE correction to all uptake metrics of each lesion and when applying correction for uptake time variability to the SUR metrics. The observed correlations were strongest when both corrections were applied to SURMAX and when the patients harboring gene amplification were grouped with the wild type: p ≤ 0.001; ROC area under the curve = 0.77 and 0.75 for the two different segmentations, respectively, with a mean specificity of 0.69 and sensitivity of 0.85. CONCLUSION: The correlations observed after applying the described corrections show potential for assigning probabilities for the KRAS missense mutation status in CLM using 2-[18F]FDG PET images.

Relatives' views of health care in the last year of life.

This article reports the views of 155 relatives of patients who died during a 12-month period with varying degrees of palliative care service (hospital-based, home care and no palliative care). Although overall care was rated as excellent or good by the majority of interviewees, the Critical Incident Technique (Flanagan, 1954) was used to gather examples of good and poor care from relatives' perspectives. These incidents are recounted here under a framework describing the process of care from access to services through to care at the time of death and aftercare for relatives. The range of incidents reported suggest that relatives consider all aspects of care - technical and interpersonal - as important towards the end of life, but particular importance is placed on the attitudinal and dignity-preserving aspects of care. The movement to integrate principles of palliative care into all clinical practice is reinforced by the findings from this study.

Formal strategic planning in the United States today.

The author sets out an appraisal of the state of corporate-strategic planning in the United States. He deals with the chronology of planning development before appraising the 'state of the art'. The appraisal utilizes the author's own set of criteria which are comprehensive and provide a framework against which individuals and companies can assess their own systems. The author deals in some detail with the nature of planning systems in different types of organization and provides valuable insight into the current state of strategic planning and a useful framework for critical analysis.