Factors associated with contralateral preventive mastectomy

INTRODUCTION: Contralateral prophylactic mastectomy (CPM) is an option for women who wish to reduce their risk of breast cancer or its local recurrence. There is limited data on demographic differences among patients who choose to undergo this procedure. METHODS: The population-based Florida cancer registry, Florida’s Agency for Health Care Administration data, and US census data were linked and queried for patients diagnosed with invasive breast cancer from 1996 to 2009. The main outcome variable was the rate of CPM. Primary predictors were race, ethnicity, socioeconomic status (SES), marital status and insurance status. RESULTS: Our population was 91.1% White and 7.5% Black; 89.1% non-Hispanic and 10.9% Hispanic. Out of 21,608 patients with a single unilateral invasive breast cancer lesion, 837 (3.9%) underwent CPM. Significantly more White than Black (3.9% vs 2.8%; P<0.001) and more Hispanic than non-Hispanic (4.5% vs 3.8%; P=0.0909) underwent CPM. Those in the highest SES category had higher rates of CPM compared to the lowest SES category (5.3% vs 2.9%; P<0.001). In multivariate analyses, Blacks compared to Whites (OR =0.59, 95% CI =0.42–0.83, P=0.002) and uninsured patients compared to privately insured (OR =0.60, 95% CI =0.36–0.98, P=0.043) had significantly less CPM. CONCLUSION: CPM rates were significantly different among patients of different race, socio-economic class, and insurance coverage. This observation is not accounted for by population distribution, incidence or disease stage. More in-depth study of the causes of these disparities in health care choice and delivery is critically needed

How Many Lymph Nodes Properly Stage a Periampullary Malignancy?

The impact of lymphadenectomy in prognosis and staging in periampullary malignancies remains largely undefined. We examined all pancreaticoduodenectomies for periampullary carcinomas in the SEER cancer registry from 1993 through 2003. Overall, 5465 pancreaticoduodenectomies for nonmetastatic periampullary carcinomas were identified. The cohort was comprised of 62.5% pancreatic, 18.9% ampullary, 11.6% distal bile duct, and 7.0% duodenal cancers. A linear association between the number of lymph nodes (LNs) examined and overall survival was observed overall and for pancreas and ampullary cancers for node-negative (N0) disease. Median survival for all patients with localized, N0 disease improved from 24 to 31 months, with sampling of a minimum of 10 LNs, whereas 2 and 5-year survival improved from 52 and 29%, with <10 nodes examined to 58 and 37% with 10+ nodes examined (P < 0.001). A 1-month median survival advantage was seen in patients with node-positive disease when more than 10 lymph nodes examined (15 versus 16 months, P < 0.001). Significantly better median survival and cure rates are observed after pancreaticoduodenectomy for localized periampullary adenocarcinoma when a minimum of 10 lymph nodes are examined. This benefit likely represents more accurate staging. To optimize the prognostic accuracy and prevent stage migration errors in multicenter trials a minimum of 10 lymph nodes should be obtained and examined before the determination of node-negative disease

Risk Factors Associated with Intravascular Catheter Infections in Burned Patients: A Prospective, Randomized Study

A prospective, controlled study of 101 intravascular catheter sites was undertaken to determine the importance of tubing manipulation and skin contamination in the etiology of catheter infection in burned patients. Catheters in place for 3 days were randomized to have the tubing changed every 24 or 48 hours. Catheters were removed at 72 hours and the tips cultured by the semi-quantitative technique of Maki. Hubs were cultured (by swab culture) at times of tubing change and at the time of catheter removal. Skin cultures of the area surrounding the catheter were done at the time of insertion and removal. Catheter tip infection was defined as 15 or more colony forming units. Positive cultures were found in 25.7% of the cases, and were most often due to Pseudomonas species (33%) and coagulase-negative Staphylococcus (29%). Infections occurred in 35% of arterial catheters, 27% of central, and 12% of peripheral venous catheters. No benefit was observed from changing the administration tubing at 24 hours vs. 48 hours. Hub cultures were positive 30% of the time at 24 hours, 39% at 48 hours and 41% at 72 hours. Although the isolated organisms correlated with tip cultures, false positive rates varied from 8 to 62%. Discriminant analysis showed no relationship between catheter infection and burn size or day postburn; however, the incidence of catheter infection correlated inversely with the distance of the catheter insertion site from the burn wound (p = 0.01). Furthermore, stepwise logistic multivariate analysis showed cutaneous colonization of the insertion site at the time of removal of the catheter to be a significant risk factor for catheter infection (relative risk, R.R. = 6.16).Frequent IV tubing changes are unnecessary in burn patients. An effort should be made to maximize the distance between the burn wound and the catheter insertion site. Hub contamination is not a reliable predictor of infection. Skin contamination with migration of bacteria along the catheter appears to be an important cause of intravascular catheter infection in burned patients

Effects of Argon laser radiation on aortic endothelial cells: Early membrane changes and proliferative response

Membrane fluidity, transmembrane signaling responses, and proliferative characteristics of endothelial cells were studied to characterize biochemical and molecular changes after treatment with argon laser energy. Bovine aortic endothelial cells grown in monolayers were irradiated at 50, 100, and 200 J with an argon laser (wavelength, 488 and 514 nm). Proliferation, assayed by [ 3H]thymidine incorporation, was measured daily for 6 days. An initial lag phase was observed for irradiated cells when compared to nonirradiated controls ( P < 0.03), with eventual recovery by the third day. Membrane fluidity, determined by fluorescence anisotropy, was measured 1 hr after irradiation. A decrease in static rotational motion of 1,6-diphenyl-1,3,5-hexatriene (DPH) was noted in irradiated versus nonirradiated cells indicating a decrease in membrane fluidity ( P < 0.02). Dynamic studies of intracellular calcium and pH flux utilizing fluorescent probes demonstrated a preserved response to mitogenic stimulation. An increase in intracellular Ca 2+ with a concomitant alkalinization of the intracellular milieu was observed in irradiated and non-irradiated cells in response to stimulation with endothelial cell growth factor (ECGF). These responses resemble those characterized for other mitogens. Argon laser energy applied to aortic endothelial cells decreases membrane fluidity early after irradiation. These alterations probably cause the initial lag observed in their proliferative response; however, the capacity to respond to exogenous mitogenic stimulation is maintained

A new approach for three-dimensional reconstruction of arterial ultrasonography

This report describes a computerized approach that allows the creation of realistic three-dimensional arterial images from two-dimensional contiguous slices derived from a conventional ultrasound scan. Furthermore, the study assesses the method's feasibility and accuracy by performing in vitro cadaver artery three-dimensional reconstructions. Images are digitized into a computer, with a resolution of 512 × 480 pixels, and a dynamic range of 8 bits/pixel (256 gray scale). After edge enhancement with convolution filters through the original binary data, the intraluminal and outer edges are traced and converted to a polygon vector within a defined three-dimensional space. Serial cuts, 2 mm apart, are then “stacked” into a three-dimensional model, with interpolation of polyhedra between slices. Sixteen normal and arteriosclerotic distal aortic and common iliac arteries were obtained from fresh cadavers. Three-dimensional reconstruction models were compared with gross examination of the original artery. Anatomically accurate reconstructions were obtained, all with detailed surface information. Data analyzed included diameter, area, residual lumen, and percent stenosis. Pearson's coefficients determined for the pairs of data indicated excellent correlation (≥ 0.90) between separate measurements. With use of the described technology it is feasible to perform arterial three-dimensional reconstructions on a personal computer, with detailed and accurate surface information. The three-dimensional reconstruction method used can reliably and consistently reproduce the anatomic specimens

Biomodulation of Fluorouracil in Colorectal Cancer

5-Fluorouracil (5-FU) remains the agent of choice for the treatment of colorectal cancer. Research has focused on the biomodulation of 5-FU in order to attempt to improve the cytotoxity and therapeutic effectiveness of this drug in the treatment of advanced colorectal cancer. Modulation of 5-FU by methotrexate (MTX), trimetrexate(TMTX), interferon-α (IFN-α), leucovorin (LV), or N-(phosphonacetyl)-L-asparte acid (PALA) has produced higher response rates than those observed with 5-FU alone. Methotrexate may improve the durability of response to or survival with 5-FU, but with inferior results compared with those in trials of 5-FU and leucovorin. Trimetrexate produces a number of responses, and further phase III trials are in progress to confirm the results of promising phase II trials with this drug. IFN-a has shown therapeutic efficiency when combined with 5-FU alone or with 5-FU and leucovorin, but latest studies with these combinations have shown increased toxicity. Initial single-institution phase I trials with 5-FU and PALA reported promising responses, but the latter responses with PALA were not substantiated in randomized multicenter trials. Leucovorin enhances the cytotoxic activity of 5-FU in vitro and in vivo, and several clinical trials have shown improved response rates and possible trends in improved survival when such therapy is compared with the use of 5-FU as a single-agent. More recent randomized trials have focused their attention on determining the optimal dose and schedule with this combination for producing a better clinical response with minimal toxicity. Schedules using infusional 5-FU appear to be the most active regimens when 5-FU is used as a single agent, as demonstrated by recent randomized trials. The Southwest Oncology Group (SWOG) and the Eastern Cooperative Oncology Group (ECOG) have performed separate randomized trials and have shown that the optimal regimens employ infusional 5-FU as a single agent, and that these are the least toxic regimens, perhaps more effective, and associated with a better quality of life. Future studies will focus on infusional regimens involving either short-term, high-dose protracted or long-term, low-dose protracted infusion of 5-FU, since these regimens have shown the most favorable toxicity spectrum and produced the longest survival times. Future research will also focus on the evaluation of various methods of delivery of 5-FU, including oral administration of the drug in combination with compounds that can modify its catabolism

The management of localized abdominal aortic dissections

Aortic dissections limited to the abdominal aorta occur infrequently. We have identified four cases of abdominal aortic dissection and have reviewed these in combination with 43 previously reported cases to identify factors that influence the prognosis and management of this disease. Abdominal aortic dissections are similar to thoracic dissections in their presentation, with acute shearing pain and systolic hypertension occurring commonly. Although the diagnosis may be made by ultrasonography or CT scanning, angiography is the definitive diagnostic study. Factors found to be associated with high mortality include presentation with acute pain (p < 0.0003), involvement of visceral vessels (p < 0.02), and rupture (p < 0.000002). Chronicity appears to be protective (p < 0.04), although chronic dissections may present acutely. Although prosthetic replacement of the involved aorta is the treatment of choice in most cases, nonoperative management with regular follow-up can be considered in asymptomatic chronic dissections