Background: Effective strategies for managing patients with solitary pulmonary nodules (SPN) depend critically on the pre-test probability of malignancy.

Objective: To validate two previously developed models that estimate the probability that an indeterminate solitary pulmonary nodule (SPN) is malignant, based on clinical characteristics and radiographic findings.

Methods: We retrospectively collected data on age, smoking and cancer history, nodule size, location, and spiculation from the medical records of 151 veterans (145 men, 6 women; range 39 to 87 years) with an SPN measuring 7 to 30 mm (inclusive) and a final diagnosis established by histopathology or 2-year follow-up. We compared each patient's final diagnosis to the probability of malignancy predicted by two models: one developed by investigators at the Mayo Clinic and another that we developed from patients enrolled in a VA Cooperative Study. We assessed model accuracy by calculating areas under the receiver operating characteristic (ROC) curve and model calibration by comparing predicted and observed rates of malignancy.

Results: The area under the ROC curve for the Mayo Clinic model (0.80; 95% CI 0.72-0.88) was higher than that of the VA model (0.73; 95% CI 0.64-0.82), but this difference was not statistically significant (Delta=0.07; 95% CI -0.03 to 0.16). Calibration curves showed that the probability of malignancy was underestimated by the Mayo Clinic model and overestimated by the VA model.

Conclusions: Two existing prediction models are sufficiently accurate to guide decisions about the selection and interpretation of subsequent diagnostic tests in patients with SPNs, although clinicians should also consider the prevalence of malignancy in their practice setting when choosing a model.

This issue of CHP/PCOR's Quarterly Update covers news from the Spring 2007 quarter and includes articles about:

• the HIV/AIDS International Conference in St. Petersburg, Russia, that was attended by the CHP/PCOR National Institute on Drug Abuse project team;
• a special international health section that highlights HIV/AIDS research in Zimbabwe, and two Payne lecturer talks, given by David Heymann and Peter Piot, speaking on infectious diseases and HIV/AIDS, respectively;
• two Research in Brief selections -- one highlights health care financing structures in high-income countries, and the second covers an ongoing trial that incorporates a smoking cessation program into posttraumatic stress disorder treatment at the VA;
• a Staff Spotlight feature on new CHP/PCOR core faculty member Sally Horwitz;
• two conferences -- one hosted by the Stanford International Initiative and the other a National Summit on America's Children at the Capitol.

The primary study objective is to conduct a prospective, randomized controlled clinical trial that compares the effectiveness of two approaches for delivering smoking cessation treatment for veterans with posttraumatic stress disorder (PTSD). An approach where smoking cessation treatment is integrated into mental health care for PTSD and delivered by mental health providers (experimental condition) will be compared to specialized smoking cessation clinic referral (VA's usual standard of care).

Secondary study objectives are to (a) compare the cost outcomes and cost-effectiveness of IC versus USC, (b) identify treatment process variables that explain (mediate) observed differences in smoking abstinence rates for the two study conditions, and (c) determine whether cessation from smoking is associated with worsening of symptoms of PTSD and/or depression.

Purpose: Lung cancer is a leading cause of cancer death worldwide. Although smoking remains the predominant cause of lung cancer, lung cancer in never smokers is an increasingly prominent public health issue. However, data on this topic, particularly lung cancer incidence rates in never smokers, are limited.

Methods: We reviewed the existing literature on lung cancer incidence and mortality rates among never smokers and present new data regarding rates in never smokers from the following large, prospective cohorts: Nurses' Health Study; Health Professionals Follow-Up Study; California Teachers Study; Multiethnic Cohort Study; Swedish Lung Cancer Register in the Uppsala/Orebro region; and First National Health and Nutrition Examination Survey Epidemiologic Follow-Up Study.

Results: Truncated age-adjusted incidence rates of lung cancer among never smokers age 40 to 79 years in these six cohorts ranged from 14.4 to 20.8 per 100,000 person-years in women and 4.8 to 13.7 per 100,000 person-years in men, supporting earlier observations that women are more likely than men to have non-smoking-associated lung cancer. The distinct biology of lung cancer in never smokers is apparent in differential responses to epidermal growth factor receptor inhibitors and an increased prevalence of adenocarcinoma histology in never smokers.

Conclusion: Lung cancer in never smokers is an important public health issue, and further exploration of its incidence patterns, etiology, and biology is needed.