Passive smoking and the use of noncigarette tobacco products in association with risk for pancreatic cancer: A case‐control study

Abstract

In this work, we demonstrate the possibility to modify the electric‐field distribution of a radio frequency (RF) coil to generate electric field‐free zones in the body without significantly altering the transmit sensitivity. Because implant heating is directly related to the electric‐field distribution, implant‐friendly RF transmit coils can be obtained by this approach. We propose a linear birdcage transmit coil with a zero electric‐field plane as an example of such implant‐friendly coils. When the zero electric‐field plane coincides with the implant position, implant heating is reduced, as we demonstrated by the phantom experiments. By feeding RF pulses with identical phases and shapes but different amplitudes to the two orthogonal ports of the coil, the position of the zero electric‐field plane can also be adjusted. Although implant heating is reduced with this method, a linear birdcage coil results in a whole‐volume average specific absorption rate that is twice that of a quadrature birdcage coil. To solve this issue, we propose alternative methods to design implant‐friendly RF coils with optimized electromagnetic fields and reduced whole‐volume average specific absorption rate. With these methods, the transmit field was modified to reduce RF heating of implants and obtain uniform transmit sensitivity. Magn Reson Med, 2011. © 2010 Wiley‐Liss, Inc.

Familial association of pancreatic cancer with other malignancies in Swedish families

“…An approximately twofold increased risk for pancreatic cancer was observed among ever smokers compared with non-smokers (Fuchs et al, 1996;Muscat et al, 1997;Hassan et al, 2007). Smoking is also a major risk factor of lung, oesophagus and kidney cancers (Chiu et al, 2001;Ghaneh et al, 2007).…”

Active and Passive Smoking and the Risk of Pancreatic Cancer in the Netherlands Cohort Study

“…Exclusion of tobacco smokers from such studies is important to estimate the independent effect of passive smoking. Thus far, four case-control (14)(15)(16)(17) and four cohort studies (7,9,18,19) have examined the relationship between passive smoking exposure and the risk of pancreatic cancer. Three of these studies observed a positive association with passive smoking in never smokers (7,15,18).…”

Secondhand Tobacco Smoke

“…pdf) and three case-control (Villeneuve et al, 2004;Hassan et al, 2007;Lo et al, 2007; the former two studies are summarized in Table 2.18 available at http://monographs.iarc.fr/ENG/ Monographs/vol100E/100E-02-Table2.18.pdf).…”

“…Data from the majority of the studies (Nishino et al, 2001;Villeneuve et al, 2004;Gallicchio et al, 2006;Hassan et al, 2007;Bao et al, 2009) suggested lack of an association of cancer of the pancreas with never smokers exposed to secondhand tobacco smoke in adulthood at home or at work. (RR 1.2 (95%CI: 0.45-3.1) and 1.21 (95%CI: 0.60-2.44) respectively).…”