A prospective study of peri-diagnostic and surgical wait times for patients with presumptive colorectal, lung, or prostate cancer

The objective of this study was to prospectively measure peri-diagnostic and surgical time intervals for patients with suspected colorectal, lung, or prostate cancer. Prospective eligible patients were referred to a regional hospital in Ottawa, Canada between February 2004 and February 2005 for diagnostic assessment of presumptive colorectal, lung, or prostate cancer. Chart abstractions were used to measure nine time intervals; the primary interval was the date of referral for diagnostic assessment to the date the patient was informed of the diagnosis. Health-related quality-of-life (HRQL) was assessed 5 days following the patient being informed of their diagnosis. The median (IQR) time for the primary interval was 71 (30-110), 37 (29-49), and 81 (56-100) days for colorectal, lung, and prostate patients, respectively (Kruskal-Wallis P=0.0001). This interval was significantly less for colorectal patients diagnosed with cancer than for those without cancer (median difference=59.0 days; Wilcoxon P=0.003). No differences in HRQL existed for patients with cancer and those without. Colorectal and prostate patients wait longer between referral for suspected cancer and being informed of their diagnosis than current recommendations. The shorter diagnostic intervals for colorectal patients with cancer suggest clinicians have an effective process for triaging patients referred for diagnostic assessment.

Breast MRI in the evaluation of locally recurrent or new breast cancer in the postoperative patient: correlation of morphology and enhancement features with the BI-RADS category

BACKGROUND

While breast magnetic resonance imaging (MRI) is a highly sensitive test for detecting breast carcinoma, its specificity is lower, and several methods have been described on how to optimize specificity.

PURPOSE

To compare the specificity and sensitivity of the BI-RADS category with the Fischer score in breast MRI for diagnosing cancer in women previously treated for breast cancer.

MATERIAL AND METHODS

Women referred for evaluation of possible local recurrence or new breast cancer underwent breast MRI examination. Morphologic and kinetic enhancement characteristics were evaluated. BI-RADS category and Fischer score were assigned for each enhancing lesion and compared using a chi-square test. Sensitivity, specificity,and positive predictive values for 27 morphologic and enhancement characteristics were calculated. Pathologic diagnosis was obtained in all patients with enhancing lesions who had ultrasound or mammographic correlation. In those without correlate, 6-, 12-, and 24-month follow-up breast MRIs were obtained. Interobserver kappa correlation was determined for each variable studied.

RESULTS

34 benign and 32 malignant lesions were identified in 26 of 30 patients. BIRADS category yielded a specificity of 77.1% and a sensitivity of 81.8%. Fischer score had a lower specificity and sensitivity (62.9% and 72.7%, respectively) (P<0.0001). Of the 27 variables studied, >100% enhancement was more sensitive than BI-RADS for malignant lesions. Specificity was highest for rim enhancement (97.1%), but sensitivity was low (24.2%). Interobserver kappa correlation was good for all 27 characteristics(k=0.84), and highest for BI-RADS assessment (k=0.91).

CONCLUSION

BI-RADS category in breast MRI had the highest combination of specificity and sensitivity, and the highest interobserver correlation. Fischer score and other morphologic and enhancement features lack sensitivity or specificity and do not have high positive predictive values when analyzed as single independent variables.

Cost of applying the K/DOQI guidelines for bone metabolism and disease to a cohort of chronic hemodialysis patients

Hyperphosphatemia is a common feature of advanced chronic kidney disease (CKD) and is treated routinely with oral calcium-based phosphate binders. In 2003, the National Kidney Foundation Kidney Disease Outcomes and Quality Initiative (K/DOQI) published Clinical Practice Guidelines (CPGs) for the treatment of Bone Metabolism and Disease in CKD. These advocate broad usage of expensive non-calcium-based phosphate binders such as sevelamer. This study was designed to determine the cost of implementation of the K/DOQI CPGs as they pertain to phosphate binding in a large Canadian hemodialysis (HD) unit. Laboratory and medication data for all chronic HD patients at the Ottawa Hospital were reviewed (n=416). Patients meeting each of the relevant K/DOQI guidelines were identified. Where guidelines would recommend a switch to non-calcium binders, equivalent sevelamer doses were estimated. The cost of implementing each guideline was then calculated individually and an estimate total cost of implementing all the guidelines was derived. Overall, 53% (222) patients fulfilled at least one criterion for sevelamer use. The yearly cost of implementation of the K/DOQI guidelines at this center was estimated at 500,605 dollars (American dollars). Given the significant cost, widespread adoption of the K/DOQI CPGs for Bone Metabolism and Disease should await the publication of compelling data demonstrating significant improved outcomes in patients treated with sevelamer.

Diagnostic assessment of suspected cancer: Prospective cohort study of diagnostic delay intervals across three disease sites

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Background: Diagnostic assessment of patients with suspected cancer can involve multiple points of delay. Methods: We conducted a cohort study of prospective eligible patients referred to a regional hospital in Ottawa, Ontario, Canada over a 12 month period (2004 to 2005) for diagnostic assessment of suspected colorectal (C), lung (L) or prostate (P) cancer. The study addressed three different disease sites, each with a different pre-existing model of care delivery, so that variability could be described. Measurement of diagnostic delay intervals included days to diagnosis (from referral to diagnosis communicated to the patient) and, for patients with cancer, to surgery and to oncology consultation. Differences between disease sites for diagnostic delay intervals, quality of life, and patient satisfaction were analyzed. Results: The proportion of patients who were diagnosed with cancer was: 6.8% (9/132) for C; 80.2% (81/101) for L; and 35% (41/116) for P. The mean [SD] days to diagnosis was significantly less for L (45 [32]) than for either C (81 [68]) for P (82 [43]), (p=.0001). It was also significantly less for patents diagnosed with cancer (57.8)[41.4]) than for those without cancer (79.3)[58.9]) (difference -21.5; 95% CI -33 to -9; p=.0003); a finding which held when C was analyzed separately (33.8 [48.9] vs 84.8 [67.7]; p=.04). L patients had worse physical and mental functioning as measured by the SF36 Physical and Mental Component Scores. Patient satisfaction did not differ across disease site or for patients with and without cancer. Conclusions: Most studies of diagnostic delay intervals use administrative data. This study is unique in prospectively measuring intervals that cannot be captured from administrative data and thus provides important benchmark measures. L patients were most likely to have cancer. Although C patients were unlikely to have cancer, the diagnostic interval was substantially shorter in those with cancer than in those without, suggesting that clinicians have an effective process for triaging patients referred for diagnostic assessment.

No significant financial relationships to disclose.

Transcriptional analysis of human peripheral blood mononuclear cells after influenza immunization

Influenza A virus is a major cause of morbidity and mortality worldwide. There is a large knowledge base on the immune response to influenza. However, few studies have focused on global gene expression in immune cells after antigenic challenge. A better understanding of the host immune response is required for the development of more efficient means of prevention and treatment of influenza. In this study, global gene expression in peripheral blood mononuclear cells (PBMCs) after influenza immunization was analyzed. The differential gene expression in antigen-stimulated and non-stimulated PBMCs was determined by cDNA microarrays. To determine whether a specific gene profile was present during a proliferative memory cell response to influenza antigens, gene expression in response to PHA was compared with antigen-stimulated PBMCs. PHA induced the upregulation of 201 genes while influenza virus antigen upregulated more than triple that is 630 genes out of 1700 genes analyzed. Both influenza antigen and PHA commonly upregulated 138 genes. Interferon (IFN)-related genes were induced by influenza but not by PHA. The interferon-gamma induced protein precursor 10 (IP-10) was upregulated 27-fold while the interferon-induced 54 kDa protein exhibited a 13-fold increase. The following gene families were also selectively upregulated by influenza antigens: complement ligands and receptors, T cell activation genes, growth factors, genes related to antigen processing and inflammatory responses. With PHA, the genes TNF-R, CTSG, CD3 delta, C8B, CRF1 and CCR2 had higher expression compared with the viral antigen stimulation. Neutrophil defensins alpha-1 and two C-C chemokines, proteins MIP-1-beta and MIP-4, were among the genes upregulated by both PHA and influenza antigens. The results suggest that interferon-induced genes are one of the main transcriptional targets during the immune response to influenza virus.