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Introduction : Advances in breast cancer (BC) diagnosis and treatment have increased the number of long-term survivors. Consequently, primary BC survivors are at a greater risk of developing second primary cancers (SPCs). The risk factors for SPCs among BC survivors including sociodemographic characteristics, cancer treatment, comorbidities, and concurrent medications have not been comprehensively examined. The purpose of this study is to assess the incidence and clinicopathologic factors associated with risk of SPCs in BC survivors. Methods We analyzed 171, 311 women with early-stage primary BC diagnosed between January 2000-December 2015 from the Medicare-linked Surveillance Epidemiology and End Results (SEER-Medicare) database. SPC was defined as any diagnosis of malignancy occurring within the study period and at least six months after primary BC diagnosis. Univariate analyses compared baseline characteristics between those who developed a SPC and those who did not. We evaluated the cause-specific hazard of developing a SPC in the presence of death as a competing risk. Results Of the study cohort, 21,510 (13%) of BC survivors developed a SPC and BC was the most common SPC type (28%). The median time to SPC was 44 months. Women who were white, older, and with fewer comorbidities were more likely to develop a SPC. While statins [hazard ratio (HR) 1.066 (1.023–1.110)] and anti-hypertensives [HR 1.569 (1.512–1.627)] increased the hazard of developing a SPC, aromatase inhibitor therapy [HR 0.620 (0.573–0.671)] and bisphosphonates [HR 0.905 (0.857–0.956)] were associated with a decreased hazard of developing any SPC, including non-breast SPCs. Conclusion Our study shows that specific clinical factors including type of cancer treatment, medications, and comorbidities are associated with increased risk of developing SPCs among older BC survivors. These results can increase patient and clinician awareness, target cancer screening among BC survivors, as well as developing risk-adapted management strategies.

BACKGROUND Racial disparities in resection of non-small cell lung cancer (NSCLC) are well documented. Patient-level and system-level factors only partially explain these findings. Although physician-related factors have been suggested as mediators, empirical evidence for their contribution is limited. OBJECTIVE To determine if racial disparities in receipt of thoracic surgery persisted after patients had a surgical consultation and whether there was a physician contribution to disparities in care. METHODS The authors identified 19,624 patients with stage I-II NSCLC above 65 years of age from the Surveillance-Epidemiology and End-Results-Medicare database. They studied black and white patients evaluated by a surgeon within 6 months of diagnosis. They assessed for racial differences in resection rates among surgeons using hierarchical linear modeling. Our main outcome was receipt of NSCLC resection. A random intercept was included to test for variability in resection rates across surgeons. Interaction between patient race and the random surgeon intercept was used to evaluate for heterogeneity between surgeons in resection rates for black versus white patients. RESULTS After surgical consultation, black patients were less likely to undergo resection (adjusted odds ratio, 0.57; 95% confidence interval, 0.47-0.69). Resection rates varied significantly between surgeons (P

Rationale: Chronic obstructive pulmonary disease (COPD) is a well-established independent risk factor for lung cancer; however, the literature on the association between asthma and lung cancer is m...

Background Gastroenteropancreatic neuroendocrine tumors (GEP‐NETs) are increasingly common malignancies and tend to have favorable long‐term prognoses. Somatostatin analogues (SSA) are a first‐line treatment for many NETs. Short‐term experiments suggest an association between SSAs and hyperglycemia. However, it is unknown whether there is a relationship between SSAs and clinically significant hyperglycemia causing development of diabetes mellitus (DM), a chronic condition with significant morbidity and mortality. Aim In this study, we aimed to compare risk of developing DM in patients treated with SSA vs no SSA treatment. Methods and Results Using the Surveillance, Epidemiology, and End Results (SEER) database and linked Medicare claims (1991‐2016), we identified patients age 65+ with no prior DM diagnosis and a GEP‐NET in the stomach, small intestine, appendix, colon, rectum, or pancreas. We used χ 2 tests to compare SSA‐treated and SSA‐untreated patients and multivariable Cox regression to assess risk factors for developing DM. Among 8464 GEP‐NET patients, 5235 patients had no prior DM and were included for analysis. Of these, 784 (15%) patients received SSAs. In multivariable analysis, the hazard ratio of developing DM with SSA treatment was 1.19, which was not statistically significant (95% CI 0.95‐1.49). Significant risk factors for DM included black race, Hispanic ethnicity, prior pancreatic surgery, prior chemotherapy, tumor size >2 cm, pancreas tumors, and higher Charlson scores. Conclusion DM was very common in GEP‐NET patients, affecting 53% of our cohort. Despite prior studies suggesting an association between SSAs and hyperglycemia, our analysis found similar risk of DM in SSA‐treated and SSA‐untreated GEP‐NET patients. Further studies are needed to better understand this relationship. As NET patients have increasingly prolonged survival, it is crucial to identify chronic conditions such as DM that these patients may be at elevated risk for.

Background Medical centers with varying levels of expertise treat gastroenteropancreatic neuroendocrine tumors (GEP-NETs), which are relatively rare tumors. This study assesses the impact of center volume on GEP-NET treatment outcomes. Methods We used the Surveillance, Epidemiology, and End Results (SEER) registry linked to Medicare claims data. The data includes patients diagnosed between 1995 and 2010 who had no health maintenance organization (HMO) coverage, participated in Medicare parts A and B, were older than 65 at diagnosis, had tumor differentiation information, and had no secondary cancer. We identified medical centers at which patients received GEP-NET treatment (surgery, chemotherapy, somatostatin analogues, or radiation therapy) using Medicare claims data. Center volume was divided into 3 tiers – low, medium, and high – based on the number of unique GEP-NET patients treated by a medical center over 2 years. We used Kaplan-Meier curves and Cox regression to assess the association between volume and disease-specific survival. Results We identified 899 GEP-NET patients, of whom 37, 45, and 18% received treatment at low, medium volume, and high-volume centers, respectively. Median disease-specific survival for patients at low and medium tiers were 1.4 years and 5.3 years, respectively, but was not reached for patients at high volume centers. Results showed that patients treated at high volume centers had better survival than those treated in low volume centers (HR: 0.63, 95% CI: 0.4–0.9), but showed no difference in outcomes between medium and high-volume centers. Conclusions Our results suggest that for these increasingly common tumors, referral to a tertiary care center may be indicated. Physicians caring for GEP-NET patients should consider early referral to high volume centers.

Video-assisted thoracoscopic surgery (VATS) and open lobectomy are both standard of care for the treatment of early-stage non-small cell lung cancer (NSCLC) because of equivalent long-term survival.To evaluate whether the improved perioperative outcomes associated with VATS lobectomy are explained by surgeon characteristics, including case volume and specialty training.We analyzed the Surveillance, Epidemiology, and End Results-Medicare-linked registry to identify stage I-II NSCLC in patients above 65 years of age. We used a propensity score model to adjust for differences in patient characteristics undergoing VATS versus open lobectomy. Perioperative complications, extended length of stay, and perioperative mortality among patients were compared after adjustment for surgeon's volume and specialty using linear mixed models. We compared survival using a Cox model with robust standard errors.We identified 9,508 patients in the registry who underwent lobectomy for early-stage NSCLC. VATS lobectomies were more commonly performed by high-volume surgeons (P 0.001) and thoracic surgeons (P = 0.01). VATS lobectomy was associated with decreased adjusted odds of cardiovascular complications (odds ratio [OR] = 0.65; 95% confidence interval [CI] = 0.47-0.90), thromboembolic complications (OR = 0.47; 95% CI = 0.38-0.58), extrapulmonary infections (OR = 0.75; 95% CI = 0.61-0.94), extended length of stay (OR = 0.47; 95% CI = 0.40-0.56), and perioperative mortality (OR = 0.33; 95% CI = 0.23-0.48) even after controlling for differences in surgeon volume and specialty. Long-term survival was equivalent for VATS and open lobectomy (hazard ratio = 0.95; 95% CI = 0.85-1.08) after controlling for patient and tumor characteristics, surgeon volume, and specialization.VATS lobectomy for NSCLC is associated with better postoperative outcomes, but similar long-term survival, compared with open lobectomy among older adults, even after controlling for surgeon experience.

BackgroundOverdiagnosis among clinically detected lung cancers likely consists of cases that are non-aggressive and slowly progressive and will never disseminate, cause symptoms or be a threat to a subject’s survival, even if untreated. In this study, we estimate the prevalence of non-aggressive lung cancers from a large, population-based cancer registry.MethodsWe identified individuals ≥65 years with histologically confirmed, untreated stage I non-small cell lung cancers (NSCLCs) from the Surveillance, Epidemiology, and End Results-Medicare registry. We estimated the rate of non-aggressive lung cancers by determining the point at which the cumulative lung cancer-specific survival curve no longer changed (ie, the slope approaches zero). At this point, there are no additional deaths due to progressive lung cancer observed among untreated patients after adjusting for deaths from competing risks (these long-term survivors can be considered ‘non-aggressive cases).ResultsThe overall rate of non-aggressive cancers among 2197 clinically detected cases of untreated stage I NSCLC was 2.4%, 95% CI: 1.0% to 3.8%. The rate of non-aggressive cancer was 1.9% (95% CI: 0.0% to 4.9%) for women and 2.4% (95% CI: 0.7% to 4.1%) for men (p=0.84). When stratifying by tumour size, non-aggressive cancer rates were 10.2% (95% CI: 0.0% to 29.3%), 2.1% (95% CI: 0.0% to 9.2%), 4.9% (95% CI: 0.0% to 10.3%), 1.8% (95% CI: 0.0% to 5.2%) and 0.0% (95% CI: 0.0% to 1.0%) for tumour sizes 45 mm (p=0.30).DiscussionWe found relatively low rates of non-aggressive cancers among clinically detected, stage I NSCLC regardless of sex or size. Our findings suggest that most clinically diagnosed early stage cancers should be treated with curative intent.

Toxicity is a main concern limiting the use of chemotherapy and radiotherapy (RT) for elderly patients with non-small cell lung cancer (NSCLC). The objective of this study was to assess the rates of treatment-related toxicity among elderly stage IIIB and IV NSCLC patients.We used the Surveillance, Epidemiology, and End Results registry linked to Medicare records to identify 2596 stage IIIB and 14,803 stage IV NSCLC patients aged 70 years and above, diagnosed in 2000 or later. We compared rates of toxicity requiring hospitalization according to treatment (chemotherapy, RT, or chemoradiation [CRT]) in unadjusted and adjusted models controlling for selection bias using propensity scores.Among stage IIIB patients, rates of any severe toxicity were 10.1%, 23.8%, 30.4%, and 39.2% for patients who received no treatment, RT, chemotherapy alone, and CRT, respectively. In stage IV patients, rates of any severe toxicity were 31.5% versus 13.5% among those treated with and without chemotherapy, respectively. In stage IIIB patients treated with CRT, the most common toxicities was esophagitis (odds ratio, 48.5; 95% confidence interval, 6.7-350.5). Among stage IV patients treated with chemotherapy, the risk of toxicity was highest for neutropenia (odds ratio, 8.4; 95% confidence interval, 6.1-11.5).Toxicity was relatively common among stage IIIB patients with up to a 6-fold increase in elderly individuals treated with CRT and a 4-fold increase in toxicities among stage IV patients. This information should be helpful to guide discussions about the risk-benefit ratio of chemotherapy and RT in elderly patients with advanced NSCLC.

Rationale: Characteristics and outcomes of lung cancer in patients with idiopathic pulmonary fibrosis (IPF) in the United States remain understudied. Objectives: To determine the tumor characteristics and survival of patients with IPF with non–small cell lung cancer (NSCLC) using U.S. population–based data. Methods: We selected Medicare beneficiaries from the Surveillance, Epidemiology, and End Results registry with histologically confirmed NSCLC diagnosed between 2007 and 2011. IPF was identified using two validated claims-based algorithms. We compared tumor characteristics and used logistic and Cox regression to compare rates of stage-appropriate therapy and of overall and lung cancer–specific survival in those with IPF and without IPF. Results: A total of 54,453 patients with NSCLC were included. Those with IPF were more likely to be diagnosed at an earlier stage (P

Cardiovascular disease (CVD) is a leading cause of mortality in early-stage breast cancer survivors. Recent studies suggest that bisphosphonates may decrease CVD risk in older patients.This study sought to assess whether bisphosphonate use is associated with lower rates of incident CVD events among early-stage breast cancer survivors.Longitudinal, population-based cohort study was conducted by using data from the Surveillance, Epidemiology and End Results registry linked to Medicare claims. We identified women65 years with no history of CVD who were diagnosed with stage 0-III primary breast cancer between 2007 and 2010. Our primary outcome was a composite of incident angina pectoris, myocardial infarction, atrial fibrillation/flutter, heart failure, or stroke within 36 months of cancer diagnosis. Bisphosphonate use was defined as the presence of ≥1 pharmacy claim from 6 months prior to cancer diagnosis to the incident CVD event. We used propensity scores to create a matched group of breast cancer survivors without bisphosphonate exposure to compare rates of incident CVD events.A total of 2178 breast cancer survivors had ≥1 bisphosphonate prescription; the average length of bisphosphonate use was 15 months. Analyses of the matched data showed that 13.0% of bisphosphonate users and 23.4% of non-bisphosphonate users experienced an incident CVD event (p 0.0001) after breast cancer diagnosis. Bisphosphonate use was significantly associated with fewer incident CVD events (hazard ratio: 0.51, 95% confidence interval: 0.44 to 0.59).Bisphosphonate use is associated with lower incidence of CVD events among older early-stage breast cancer survivors. Future studies should prospectively evaluate whether bisphosphonate use can decrease CVD incidence.

Surgeon procedure volume influences outcomes of patients undergoing cancer operations. Limited data are available, however, on the volume-outcome relationship for video-assisted thoracoscopic surgery (VATS) in the treatment of non–small cell lung cancer (NSCLC). In this study, we used population-based data to evaluate the extent to which surgeon volume is associated with postoperative and long-term oncological outcomes following VATS resection for older patients with early-stage NSCLC. Stage I NSCLC patients >65 years treated with VATS wedge, segmentectomy, or lobectomy between 2000 and 2010 were identified from the Surveillance, Epidemiology, and End Results registry linked to Medicare. Surgeon volume was grouped into tertiles (low, intermediate, and high). Outcomes included perioperative complications, intensive care unit admission, extended length of stay, perioperative (30-day) mortality, and long-term overall and lung cancer-specific survival. We used propensity score methods to compare adjusted survival of patients by surgical volume group. A total of 2295 study patients were identified. Patients treated by high-volume surgeons had decreased intensive care unit admissions (hazard ratio [HR]: 0.46, 95% CI: 0.41-0.51) and postoperative length of stay (HR: 0.75, 95% CI: 0.61-0.92). Adjusted analyses showed that overall (HR: 0.73, 95% CI: 0.62-0.87) and lung cancer-specific (HR: 0.76, 95% CI: 0.58-0.99) survival was better for patients treated by high-volume surgeons. Elderly stage I NSCLC patients undergoing VATS by high-volume surgeons have reduced postoperative complications and improved survival. Organization of care favoring referrals of VATS candidates to high-volume providers may help improve the outcomes of patients with early-stage lung cancer.

Objectives: Pancreatic ductal adenocarcinoma (PDAC) remains a highly lethal disease. Diabetes mellitus (DM) is both a risk factor for and a sequela of PDAC. Metformin is a commonly prescribed biguanide oral hypoglycemic used for the treatment of type II DM. We investigated whether metformin use before PDAC diagnosis affected survival of patients with DM, controlling confounders such as diabetic severity. Methods: We used the Surveillance, Epidemiology, and End Results registry (SEER)-Medicare linked database to identify patients with PDAC diagnosed between 2007 and 2011. The diabetic TO comorbidity severity index (DCSI) controlled for DM severity. Inverse propensity weighted Cox Proportional-Hazard Models assessed the association between metformin use and overall survival adjusting for relevant confounders. Results: We identified 1,916 patients with PDAC and pre-existing DM on hypoglycemic medications at least 1 year before cancer diagnosis. Of these, 1,098 (57.3%) were treated with metformin and 818 (42.7%) with other DM medications. Mean survival for those on metformin was 5.5 months compared with 4.2 months for those not on metformin (P

In the treatment of stage III non-small cell lung cancer (NSCLC), three-dimensional conformal radiotherapy (3D-RT) is the standard method for radiation delivery; however, intensity-modulated radiotherapy (IMRT) has been rapidly adopted. These two modalities may lead to similar survival, warranting a closer scrutiny of the costs involved.The purpose of this study is to compare radiotherapy-related and total costs of older patients with NSCLC treated with 3D-RT versus IMRT.We conducted a population-based study of all Medicare beneficiaries aged 65 years or older in a Surveillance, Epidemiology and End Results region. Patients were diagnosed with stage III NSCLC diagnosed between 2002 and 2009. Patients received IMRT or 3D-RT in combination with chemotherapy within 4 months of diagnosis. Radiotherapy-related and total adjusted cost and survival of patients receiving 3D-RT versus IMRT were compared using propensity scores methods.Of the 2,418 patients in study, 314 (13%) received IMRT. Adjusted analyses showed no difference in overall survival (hazard ratio, 0.97; 95% confidence interval [CI], 0.85-1.12) in patients treated with 3D-RT versus IMRT. After adjusting for propensity scores, RT-related costs (estimated difference, $6,850; 95% CI, $5,532-$8,168) and total costs (estimated difference, $8,713; 95% CI, $4,376-$13,051) were significantly higher among patients undergoing IMRT.The rapid adoption of IMRT for the treatment of stage III NSCLC has occurred in the absence of evidence from prospective randomized trials. Our results show that IMRT is associated with similar survival but increased costs, underscoring the need for continued research in IMRT and other new technologies.

Prior studies have shown an anticancer effect of statins in patients with certain malignancies. However, it is unclear whether statins have a mortality benefit in lung cancer. We compared survival of patients with stage IV non-small cell lung cancer (NSCLC) receiving vs. not receiving statins prior to diagnosis.Using data from the Surveillance, Epidemiology and End Results registry linked to Medicare claims, we identified 5118 patients 65 years of age diagnosed with stage IV NSCLC between 2007 and 2009. We used propensity score methods to assess the association of statin use with overall and lung cancer-specific survival while controlling for measured confounders.Overall, 27% of patients were on statins at time of lung cancer diagnosis. Median survival in the statin group was 7 months, compared to 4 months in patients not treated with statins (p0.001). Propensity score analyses found that statin use was associated with improvement in overall (hazard ratio [HR]: 0.76, 95% confidence interval [CI]: 0.73-0.79) and lung cancer-specific survival (HR: 0.77, 95% CI: 0.73-0.81), after controlling for baseline patient characteristics, cancer characteristics, staging work-up and chemotherapy use.Statin use is associated with improved survival among patients with stage IV NSCLC suggesting a potential anticancer effect. Further research should evaluate plausible biological mechanisms as well as test the effect of statins in prospective clinical trials.

Background Obesity is a robust predictor of poor asthma control in younger adults. Given the high prevalence of asthma and obesity in older Americans, weight reduction could benefit asthma management in this population. Objective To assess the association between obesity and asthma outcomes among older adults. Methods We recruited from urban primary care clinics a prospective cohort of nonsmoking individuals with asthma who were 60 years or older without a history of other respiratory diseases. At baseline, body mass index (BMI) measurements were classified as normal (BMI, 18–25), overweight (BMI, 25–30), or obese (BMI, >30). Measures of asthma morbidity (Asthma Control Questionnaire [ACQ], and Mini Asthma Quality of Life Questionnaire [Mini-AQLQ]) and asthma-related resource utilization (inpatient or outpatient) were taken at baseline and at 3- and 12-month interviews. We used generalized estimating equation models to assess associations between obesity and asthma outcomes after controlling for potential confounders. Results Of the 437 older adults with asthma in the study, 17% had a normal BMI, 32% were overweight, and 51% were obese. Unadjusted analyses revealed that obesity was associated with lower ACQ scores (odds ratio [OR], 1.19; 95% confidence interval [CI], 1.09–1.31) and poorer Mini-AQLQ scores (OR, 1.21; 95% CI, 1.11–1.33). Adjusted analyses revealed no significant association between obesity and ACQ (OR, 1.05; 95% CI, 0.96–1.15) and Mini-AQLQ (OR, 1.08; 95% CI, 0.99–1.19). Conclusion Our study suggests that obesity is not independently associated with worse asthma outcomes in older adults, reflecting potential differences in the mechanisms that link obesity with asthma control in older vs younger populations.

Background Some interstitial lung diseases are associated with lung cancer. However, it is unclear whether asymptomatic interstitial lung abnormalities convey an independent risk. Objectives The goal of this study was to assess whether interstitial lung abnormalities are associated with an increased risk of lung cancer. Methods Data from all participants in the National Lung Cancer Trial were analyzed, except for subjects with preexisting interstitial lung disease or prevalent lung cancers. The primary analysis included those who underwent low-dose CT imaging; those undergoing chest radiography were included in a confirmatory analysis. Participants with evidence of reticular/reticulonodular opacities, honeycombing, fibrosis, or scarring were classified as having interstitial lung abnormalities. Lung cancer incidence and mortality in participants with and without interstitial lung abnormalities were compared by using Poisson and Cox regression, respectively. Results Of the 25,041 participants undergoing low-dose CT imaging included in the primary analysis, 20.2% had interstitial lung abnormalities. Participants with interstitial lung abnormalities had a higher incidence of lung cancer (incidence rate ratio, 1.61; 95% CI, 1.30-1.99). Interstitial lung abnormalities were associated with higher lung cancer incidence on adjusted analyses (incidence rate ratio, 1.33; 95% CI, 1.07-1.65). Lung cancer-specific mortality was also greater in participants with interstitial lung abnormalities. Similar findings were obtained in the analysis of participants undergoing chest radiography. Conclusions Asymptomatic interstitial lung abnormalities are an independent risk factor for lung cancer that can be incorporated into risk score models.

Background:Limited resection and stereotactic body radiotherapy (SBRT) have emerged as treatment options for older patients with early-stage non–small-cell lung cancer (NSCLC), who are not good candidates for lobectomy.Methods:We used the Surveillance, Epidemiology and End Results-Medicare registry to identify patients older than 65 years with stage I to II NSCLC and negative lymph nodes treated with SBRT versus limited resection. We fitted a propensity score model predicting the use of SBRT and compared adjusted overall survival of patients treated with SBRT versus limited resection. Secondary analyses stratified the sample by type of limited resection (wedge versus segmentectomy), age (⩽75 versus >75 years), and tumor size (

We have used population-based data from the SEER–Medicare registry to show that adjuvant chemotherapy is associated with improved survival among elderly patients with early-stage non-small-cell lung cancer ≥4 cm. These findings extend the results of a prior RCT to the growing population of older patients with cancer. Background The role of adjuvant chemotherapy for non-small-cell lung cancer (NSCLC) stage I patients with tumors size ≥4 cm is not well established in the elderly. Patients and methods We identified 3289 patients with stage I NSCLC (T2N0M0 and tumor size ≥4 cm) who underwent lobectomy from the Surveillance, Epidemiology and End Results (SEER)–Medicare linked database diagnosed from 1992 to 2009. Overall survival and rates of serious adverse events (defined as those requiring admission to hospital) were compared between patients treated with resection alone, platinum-based adjuvant chemotherapy, or postoperative radiation (PORT) with or without adjuvant chemotherapy. Propensity scores for receiving each treatment were calculated and survival analyses were conducted using inverse probability weights based on the propensity score. Results Overall, 84% patients were treated with resection alone, 9% received platinum-based adjuvant chemotherapy, and 7% underwent PORT with or without adjuvant chemotherapy. Adjusted analysis showed that adjuvant chemotherapy [hazard ratio (HR), 0.82; 95% confidence interval (CI) 0.68–0.98] was associated with improved survival compared with resection alone. Conversely, the use of PORT with or without adjuvant chemotherapy (HR 1.91; 95% CI 1.64–2.23) was associated with worse outcomes. Patients receiving adjuvant chemotherapy had more serious adverse events compared with those treated with resection alone, with neutropenia (odds ratio, 21.2; 95% CI 5.8–76.6) being most significant. No significant difference was observed in rates of fever, cytopenias, nausea, and renal dysfunction. Conclusions Platinum-based adjuvant chemotherapy is associated with reduced mortality and increased serious adverse events in elderly patients with stage I NSCLC and tumor size ≥4 cm.

OBJECTIVE To compare the growth patterns in the first year of life between children born to perinatally HIV-infected (PHIV) vs. nonperinatally HIV-infected (NPHIV) women in the United States. DESIGN Retrospective cohort study of HIV-infected pregnant women who received care and delivered a live-born at two urban tertiary centers from January 2004 to March 2012. METHODS We collected data via chart review on demographics, behavioral risk factors, HIV clinical markers, combination antiretroviral therapy (cART), mode of HIV acquisition, pregnancy outcomes, and infant anthropometrics on study participants. Mixed-effects models were used to assess the association between maternal mode of HIV acquisition and weight-for-age z-score (WAZ), length-for-age z-score (LAZ), and weight-for-length z-score (WLZ). RESULTS Of the 152 pregnancies evaluated, 32 and 120 infants were born to 25 PHIV and 99 NPHIV women, respectively. Infants of PHIV women exhibited lower mean WAZ and LAZ throughout the first year of life in unadjusted analyses. After adjusting for potential confounders, the relationship between PHIV women and LAZ persisted (β = -0.54, P = 0.026). Small-for-gestational age for each birth anthropometric parameter (birth length, birth weight, and both birth length and weight) was associated with decreased LAZ (β = -0.48, P = 0.007), WAZ (β = -0.99, P

Limited resection is commonly used for treating older patients with early-stage non-small cell lung cancer (NSCLC) who cannot tolerate lobectomy. However, parenchymal-sparing procedures leave patients at increased risk of recurrence. The role of postoperative radiotherapy (PORT) and chemotherapy after limited resection is not established.We identified 1,929 patients with stage I-II (≤ 5 cm in size) NSCLC who underwent limited resection (wedge or segmentectomy) from the Surveillance, Epidemiology, and End Results (SEER)-Medicare linked database. Using propensity score methods, we compared toxicity and survival of patients treated with limited resection alone, PORT, adjuvant chemotherapy, or PORT and chemotherapy. We conducted secondary analysis stratifying the sample by size (2-5 cm), stage (IA vs. IB/IIA), and type of limited resection (wedge resection vs. segmentectomy).Overall, 1,656 (85.8%), 159 (8.3%), 74 (3.8%), and 40 (2.1%) patients were treated with limited resection alone, PORT, adjuvant chemotherapy, or PORT and chemotherapy, respectively. Adjusted analysis using inverse probability weighting showed that PORT (hazard ratio [HR], 1.57; 95% confidence interval [CI], 1.45-1.69), adjuvant chemotherapy (HR, 1.48; 95% CI, 1.36-1.61), and PORT and chemotherapy (HR, 1.73; 95% CI, 1.61-1.86) were associated with worse survival compared with limited resection alone. Similar results were obtained in secondary analyses. Compared with limited resection alone, the adjusted odds ratios for toxicity were 1.97 (95% CI, 1.6-2.4), 3.15 (95% CI, 2.58-3.85), 2.59 (95% CI, 2.0-3.4) for PORT, chemotherapy, and PORT and chemotherapy, respectively.PORT and adjuvant chemotherapy are not beneficial and appear to be associated with increased toxicity and worse survival after limited resection in elderly patients with early-stage NSCLC. Alternative strategies should be explored to improve local control.

Chemoradiotherapy is the standard of care for unresectable stage III non-small cell lung cancer (NSCLC). Elderly patients, who are often considered unfit for combined chemoradiotherapy, frequently receive radiation therapy (RT) alone. Using population-based data, we evaluated the effectiveness and tolerability of lone RT in unresected elderly stage III NSCLC patients.Using the Surveillance, Epidemiology and End Results (SEER) registry linked to Medicare records we identified 10,376 cases of unresected stage III NSCLC that were not treated with chemotherapy, diagnosed between 1992 and 2007. We used logistic regression to determine propensity scores for RT treatment using patients' pre-treatment characteristics. We then compared survival of patients who underwent lone RT vs. no treatment using a Cox regression model adjusting for propensity scores. The adjusted odds for toxicity among patients treated with and without RT were also estimated.Overall, 6468 (62%) patients received lone RT. Adjusted analyses showed that RT was associated with improved overall survival in unresected stage III NCSLC (hazard ratio [HR]: 0.76; 95% confidence interval [CI]: 0.74-0.79) after controlling for propensity scores. RT treated patients had an increased adjusted risk of hospitalization for pneumonitis (odds ratio [OR]: 89, 95% CI: 12-636), and esophagitis (OR: 8, 95% CI: 3-21).These data suggest that use of RT alone may improve the outcomes of elderly patients with unresected stage III NSCLC. Severe toxicity, however, was considerably higher in the RT treated group. The potential risks and benefits of RT should be carefully discussed with eligible elderly NSCLC patients.

Background Although the prognosis of elderly patients with stage IIIB and IV non-small cell lung cancer (NSCLC) is poor, it remains a common cause of cancer related admissions to the intensive care unit (ICU). The objective was to evaluate short and long-term outcomes of a population-based sample of elderly patients with advanced NSCLC who require ICU care. Methods Using combined data from the Surveillance, Epidemiology and End Results registry and Medicare files, we identified 1134 patients >65 years of age with stage IIIB and IV NSCLC admitted to an ICU with a diagnosis of respiratory, cardiac, or neurologic complications, renal failure, or sepsis. We assessed rates and predictors of death during hospitalization. The Kaplan–Meier method was used to estimate mortality rates at 90 days and 1 year post hospital discharge. Results In-hospital mortality was 33% (95% CI: 30–36%). The 90-day and 1-year mortality rate was 71% and 90%, respectively. Patients with an admitting diagnosis of sepsis had the highest rate of in-hospital mortality (59%). Of those who were alive at discharge, 52% were transferred to a skilled nursing facility, 6% to hospice, and 42% returned home. Conclusion We found that one-third of elderly patients with advanced NSCLC admitted to the ICU do not survive hospitalization. Among survivors, most patients required continued institutionalization with a very low likelihood of surviving >1 year from discharge. This data should help patients, families, and health care providers of elderly patients with advanced NSCLC make decisions regarding ICU utilization.

BACKGROUND: The potential role of postoperative radiation therapy (PORT) for patients who have completely resected, stage III nonsmall cell lung cancer (NSCLC) with N2 disease remains controversial. By using population-based data, the authors of this report compared the survival of a concurrent cohort of elderly patients who had N2 disease treated with and without PORT. METHODS: By using the Surveillance, Epidemiology, and End Results (SEER) registry linked to Medicare records, 1307 patients were identified who had stage III NSCLC with N2 lymph node involvement diagnosed between 1992 and 2005. Propensity scoring methods and instrumental variable analysis were used to compare the survival of patients who did and did not receive PORT after controlling for selection bias. RESULTS: Overall, 710 patients (54%) received PORT. Propensity score analysis indicated that PORT was not associated with improved survival in patients with N2 disease (hazard ratio [HR], 1.11; 95% confidence interval [CI], 0.97-1.27). Analyses that were limited to patients who did or did not receive chemotherapy, who received intermediate-complexity or high-complexity radiotherapy planning, or adjusted for time trends produced similar results. The instrumental variable estimator for the absolute improvement in 1-year and 3-year survival with PORT was −0.04 (95% CI, −0.15 to 0.08) and −0.08 (95% CI, −0.24 to 0.15), respectively. CONCLUSIONS: The current data suggested that PORT is not associated with improved survival for elderly patients with N2 disease. These findings have important clinical implications, because SEER data indicate that a large percentage of elderly patients currently receive PORT despite the lack of definitive evidence about its effectiveness. The potential effectiveness of PORT should be evaluated further in randomized controlled trials. Cancer 2012. © 2012 American Cancer Society.

Radiotherapy (RT) is the standard therapy for unresected stage I-II nonsmall cell lung cancer (NSCLC). Using population-based data, we compared survival and toxicity among unresected elderly patients treated with combined chemoradiotherapy (CRT) or RT alone. Using the Surveillance, Epidemiology and End Results (SEER) registry (National Cancer Institute, Bethesda, MD, USA) we identified 3,006 cases of unresected stage I-II NSCLC. We used propensity score methods to compare survival and rates of toxicity of patients treated with RT versus CRT. Overall, 844 (28%) patients received CRT. Adjusted analyses showed that CRT was associated with improved survival (hazard ratio 0.85, 95% CI 0.78-0.94). Combination therapy was also associated with better survival among stage I patients treated with intermediate complexity RT (HR 0.80, 95% CI 0.70-0.90); however, no difference in survival was observed among patients treated with complex RT. In stage II patients, CRT was associated with improved survival regardless of the RT technique (HR 0.61-0.72). CRT was associated with increased odds of toxicity. Despite increased toxicity, CRT may improve survival of elderly unresected patients with stage II disease as well as stage I NSCLC treated with intermediate RT complexity. Randomised trials are needed to clarify the balance of benefits and risk of CRT in unresected patients.

Background Lymph node (LN) metastasis is an important predictor of survival for patients with non-small cell lung cancer (NSCLC). However, the prognostic significance of the extent of LN involvement among patients with N1 disease remains unknown. A study was undertaken to evaluate whether involvement of a higher number of N1 LNs is associated with worse survival independent of known prognostic factors. Methods Using the Surveillance, Epidemiology and End Results-Medicare database, 1682 resected patients with N1 NSCLC diagnosed between 1992 and 2005 were identified. As the number of positive LNs is confounded by the total number of LNs sampled, the cases were classified into three groups according to the ratio of positive to total number of LNs removed (LN ratio (LNR)): ≤0.15, 0.16–0.5 and >0.5. Lung cancer-specific and overall survival was compared between these groups using Kaplan–Meier curves. Stratified and Cox regression analyses were used to evaluate the relationship between the LNR and survival after adjusting for potential confounders. Results Lung cancer-specific and overall survival was lower among patients with a high LNR (p 0.5 LNR groups, respectively. In stratified and adjusted analyses, a higher LNR was also associated with worse lung cancer-specific and overall survival. Conclusions The extent of LN involvement provides independent prognostic information in patients with N1 NSCLC. This information may be used to identify patients at high risk of recurrence who may benefit from aggressive postoperative therapy.

This population-based study compares opioid use in patients with non–small cell lung cancer who underwent open resection vs video-assisted thoracoscopic surgery.

Purpose Limited resection has been increasingly used in older patients with stage IA lung cancer. However, the equivalency of limited resection versus lobectomy according to histology is unknown. Methods We identified patients older than 65 years with stage IA invasive adenocarcinoma or squamous cell carcinoma ≤ 2 cm who were treated with limited resection (wedge or segmentectomy) or lobectomy in the Surveillance, Epidemiology, and End Results–Medicare database. We estimated propensity scores that predicted the use of limited resection and compared survival of patients treated with limited resection versus lobectomy. Treatments were considered equivalent if the upper 95th percentile of the hazard ratio (HR) for limited resection was ≤ 1.25. Results Overall, 27% of 2,008 patients with adenocarcinoma and 32% of 1,139 patients with squamous cell carcinoma underwent limited resection. Survival analyses, adjusted for propensity score by using inverse probability weighting, showed that limited resection was not equivalent to lobectomy in patients with adenocarcinoma (HR, 1.21; upper 95% CI,1.34) or squamous cell carcinoma (HR, 1.21; upper 95% CI, 1.39). Although patients with adenocarcinomas treated with segmentectomy had equivalent survival rates to those treated with lobectomy (HR, 0.97; upper 95% CI, 1.07), outcomes of those treated with wedge resection (HR, 1.29; upper 95% CI, 1.42) did not. Among patients with squamous cell carcinoma, neither wedge resection (HR, 1.34; upper 95% CI, 1.53) nor segmentectomy (HR, 1.19; upper 95% CI, 1.36) were equivalent to lobectomy. Conclusion We found generally that limited resection is not equivalent to lobectomy in older patients with invasive non–small-cell lung cancer ≤ 2 cm in size, although segmentectomy may be equivalent in patients with adenocarcinoma.

BACKGROUND Treatment-related immunosuppression in organ transplant recipients has been linked to increased incidence and risk of progression for several malignancies. Using a population-based cancer cohort, we evaluated whether organ transplantation was associated with worse prognosis in elderly patients with non-small cell lung cancer (NSCLC). METHODS Using the Surveillance, Epidemiology, and End Results Registry linked to Medicare claims, we identified 597 patients aged 65 years or older with NSCLC who had received organ transplants (kidney, liver, heart, or lung) before cancer diagnosis. These cases were compared to 114,410 untransplanted NSCLC patients. We compared overall survival (OS) by transplant status using Kaplan-Meier methods and Cox regression. To account for an increased risk of non-lung cancer death (competing risks) in transplant recipients, we used conditional probability function (CPF) analyses. Multiple CPF regression was used to evaluate lung cancer prognosis in organ transplant recipients while adjusting for confounders. RESULTS Transplant recipients presented with earlier stage lung cancer (P = 0.002) and were more likely to have squamous cell carcinoma (P = 0.02). Cox regression analyses showed that having received a non-lung organ transplant was associated with poorer OS (P < 0.05), whereas lung transplantation was associated with no difference in prognosis. After accounting for competing risks of death using CPF regression, no differences in cancer-specific survival were noted between non-lung transplant recipients and nontransplant patients. CONCLUSIONS Non-lung solid organ transplant recipients who developed NSCLC had worse OS than nontransplant recipients due to competing risks of death. Lung cancer-specific survival analyses suggest that NSCLC tumor behavior may be similar in these 2 groups.

502 Background: Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are relatively rare tumors, where patients seek care at medical centers with varying levels of expertise. While treatment center volume is associated with better survival in multiple cancers, it remains unknown whether the same applies to GEP-NETs. The objective of this study was to assess the impact of center volume on GEP-NET treatment outcomes. Methods: We used the Surveillance, Epidemiology, and End Results (SEER) registry linked to Medicare claims data in this study. We included patients diagnosed between 1995-2010 who had no HMO coverage, participated in Medicare parts A and B, were older than 65 at diagnosis, had full tumor grade information, and had no secondary cancer. We used Medicare claims to identify the medical centers at which patients received GEP-NET treatment (surgery, chemotherapy, somatostatin analogues, or radiation therapy). Center volume was divided into tiers – low, medium, and high – based on the number of unique GEP-NET patients treated by a medical center over two years. Kaplan-Meier curves and Cox regression were used to assess the association between volume and disease-specific survival (DSS). Results: We identified 1025 GEP-NET patients, of whom 65%, 28%, and 7% received treatment at low, medium, and high volume centers, respectively. Surgery was the most common first treatment (84-90%). Comorbidity and tumor stage distribution were similar across tiers, but the distribution of patients with poorly-differentiated tumors differed significantly (p < 0.001). Median DSS for patients at low and medium centers were 3.7 years and 6.6 years, respectively, but was not reached for patients at high volume centers. After adjusting for confounders, patients treated at high volume centers had better survival than those treated in low volume centers (HR: 0.55, 95% CI: 0.30-0.99). However, no difference in survival was noted at medium volume centers (HR: 0.98, 95% CI: 0.78-1.22). Conclusions: Our results suggest that centers with expertise in GEP-NET treatment have better patient outcomes. Thus, centralization of care, particularly of more difficult cases, may lead to improved patient outcomes.

Prior studies have shown an anticancer effect of metformin in patients with breast and colorectal cancer. It is unclear, however, whether metformin has a mortality benefit in lung cancer.To compare overall survival of patients with diabetes with stage IV non-small cell lung cancer (NSCLC) taking metformin versus those not on metformin.Using data from the Surveillance, Epidemiology, and End Results registry linked to Medicare claims, we identified 750 patients with diabetes 65-80 years of age diagnosed with stage IV NSCLC between 2007 and 2009. We used propensity score methods to assess the association of metformin use with overall survival while controlling for potential confounders.Overall, 61% of patients were on metformin at the time of lung cancer diagnosis. Median survival in the metformin group was 5 months, compared with 3 months in patients not treated with metformin (P 0.001). Propensity score analyses showed that metformin use was associated with a statistically significant improvement in survival (hazard ratio, 0.80; 95% confidence interval, 0.71-0.89), after controlling for sociodemographics, diabetes severity, other diabetes medications, cancer characteristics, and treatment.Metformin is associated with improved survival among patients with diabetes with stage IV NSCLC, suggesting a potential anticancer effect. Further research should evaluate plausible biologic mechanisms and test the effect of metformin in prospective clinical trials.

Background and purpose Combined chemoradiotherapy (CRT) is considered the standard care for unresectable stage III non-small cell lung cancer (NSCLC). There have been limited data comparing outcomes of carboplatin vs. cisplatin-based CRT, particularly in elderly. Material and methods From the Surveillance, Epidemiology and End Results-Medicare registry, we identified 1878 patients >65 years of age with unresected stage III NSCLC that received concurrent CRT between 2002 and 2009. We fitted a propensity score model predicting use of cisplatin-based therapy and compared adjusted overall and lung-cancer specific survival of carboplatin- vs. cisplatin-treated patients. Rates of severe toxicity requiring hospital admission were compared in propensity score adjusted analyses. Results Overall 1552 (83%) received carboplatin (77% in combination with paclitaxel) and 17% cisplatin (67% in combination with etoposide). Adjusted cox models showed similar overall (hazard ratio [HR]: 0.98; 95% confidence interval [CI]: 0.86–1.12) and lung cancer-specific (HR: 0.99; 95% CI: 0.84–1.17) survival among patients treated with carboplatin vs. cisplatin. Adjusted rates of neutropenia (odds ratio [OR]: 0.35; 95% CI: 0.21–0.61), anemia (OR: 0.67; 95% CI: 0.51–0.89), and thrombocytopenia (OR: 0.51; 95% CI: 0.31–0.85) were lower among carboplatin-treated patients; other toxicities were not different between groups. Conclusion Carboplatin-based CRT is associated with similar long-term survival but lower rates of toxicity. These findings suggest carboplatin may be the most appropriate chemotherapeutic agent for elderly stage III patients.

Minority patients with lung cancer are less likely to receive stage-appropriate treatment. Along with access to care and provider-related factors, cultural factors such as patients' lung cancer beliefs, fatalism, and medical mistrust may help explain this disparity.To determine cultural factors associated with disparities in lung cancer treatment.Patients with newly diagnosed lung cancer were recruited from four medical centers in New York City from 2008 to 2011. Using validated tools, we surveyed participants about their beliefs regarding lung cancer, fatalism, and medical mistrust. We compared rates of stage-appropriate treatment among blacks, Hispanics, and nonminority patients. Multiple regression analyses and structural equation modeling were used to assess whether cultural factors are associated with and/or mediate disparities in care.Of the 352 patients with lung cancer in the study, 21% were black and 20% were Hispanic. Blacks were less likely to receive stage-appropriate treatment (odds ratio [OR], 0.50; 95% confidence interval [CI], 0.27-0.93) compared with whites, even after adjusting for age, sex, marital status, insurance, income, comorbidities, and performance status. No differences in treatment rates were observed among Hispanics (OR, 1.05; 95% CI, 0.53-2.07). Structural equation modeling showed that cultural factors (negative surgical beliefs, fatalism, and medical mistrust) partially mediated the relationship between black race and lower rates of stage-appropriate treatment (total effect: -0.43, indirect effect: -0.13; 30% of total effect explained by cultural factors).Negative surgical beliefs, fatalism, and mistrust are more prevalent among minorities and appear to explain almost one-third of the observed disparities in lung cancer treatment among black patients. Interventions targeting cultural factors may help reduce undertreatment of minorities.

Cancer mortality is higher in individuals with schizophrenia, a finding that may be due, in part, to inequalities in care. We evaluated gaps in lung cancer diagnosis, treatment, and survival among elderly individuals with schizophrenia.The Surveillance, Epidemiology, and End Results database linked to Medicare records was used to identify patients 66 years or older with primary non-small cell lung cancer. Lung cancer stage, diagnostic evaluation, and rates of stage-appropriate treatment were compared among patients with and without schizophrenia using unadjusted and multiple regression analyses. Survival was compared among groups using Kaplan-Meier methods.Of the 96,702 patients with non-small cell lung cancer in the Surveillance, Epidemiology, and End Results database, 1303 (1.3%) had schizophrenia. In comparison with the general population, patients with schizophrenia were less likely to present with late-stage disease after controlling for age, sex, marital status, race/ethnicity, income, histology, and comorbidities (odds ratio = 0.82, 95% confidence interval = 0.73-0.93) and were less likely to undergo appropriate evaluation (p.050 for all comparisons). Adjusting for similar factors, patients with schizophrenia were also less likely to receive stage-appropriate treatment (odds ratio = 0.50, 95% confidence interval = 0.43-0.58). Survival was decreased among patients with schizophrenia (mean survival = 22.3 versus 26.3 months, p = .002); however, no differences were observed after controlling for treatment received (p = .40).Elderly patients with schizophrenia present with earlier stages of lung cancer but are less likely to undergo diagnostic evaluation or to receive stage-appropriate treatment, resulting in poorer outcomes. Efforts to increase treatment rates for elderly patients with schizophrenia may lead to improved survival in this group.

Introduction: Video-assisted thorcacic surgery (VATS) is considered an alternative to open lobectomy for the treatment of non–small-cell lung cancer (NSCLC). Limited data are available, however, regarding the equivalence of open versus VATS segmental resections, particularly among elderly patients. Methods: From the Surveillance, Epidemiology, and End Results–Medicare database we identified 577 stage I NSCLC patients aged more than 65 years treated with VATS or open segmentectomy. We used propensity score methods to control for differences in the baseline characteristics of patients treated with VATS versus open segmentectomy. Outcomes included perioperative complications, need for intensive care unit, extended hospital stay, perioperative mortality, and survival. Results: Overall, 27% of patients underwent VATS. VATS-treated patients had lower rates of postoperative complications (odds ratio [OR]: 0.55, 95% confidence interval [CI]: 0.37–0.83), intensive care unit admissions (OR: 0.18, 95% CI: 0.12–0.28), and decreased length of stay (OR: 0.41, 95% CI: 0.21–0.81) after adjusting for propensity scores. Postoperative outcomes were not significantly different across groups after adjusting for surgeon characteristics. Overall (hazard ratio: 0.80, 95% CI: 0.60–1.06) and lung cancer–specific (hazard ratio: 0.71, 95% CI: 0.45–1.12) survival was similar across groups. Conclusions: VATS segmentectomy can be safely performed among elderly NSCLC patients and is associated with equivalent postoperative and oncologic outcomes.

e20000Background: Current guidelines recommend the use of adjuvant platinum-based chemotherapy as the standard of care for patients with stages IB-IIIA ( ≥ 4cm) NSCLC who have undergone resection. ...

Introduction: Although lobectomy is considered the standard surgical treatment for stage IA non–small-cell lung cancer (NSCLC), wedge resection or segmentectomy are frequently performed on patients who are not lobectomy candidates. The objective of this study was to compare survival among patients with stage IA NSCLC, who are undergoing these procedures. Methods: Using the Surveillance, Epidemiology and End Results registry, we identified 3525 patients. We used logistic regression to determine propensity scores for patients undergoing segmentectomy, based on the patient's preoperative characteristics. Overall and lung cancer-specific survival of patients treated with wedge resection versus segmentectomy was compared after adjusting, stratifying, or matching patients based on propensity score. Results: Overall, 704 patients (20%) underwent segmentectomy. Analyses, adjusting for propensity scores, showed that segmentectomy was associated with significant improvement in overall (hazard ratio: 0.80, 95% confidence interval: 0.69–0.93) and lung cancer-specific survival (hazard ratio: 0.72, 95% confidence interval: 0.59–0.88) compared with wedge resection. Similar results were obtained when stratifying and matching by propensity score and when limiting analysis to patients with tumors sized less than or equal to 2 cm, or aged 70 years or younger. Conclusions: These results suggest that segmentectomy should be the preferred technique for limited resection of patients with stage IA NSCLC. The study findings should be confirmed in prospective studies.

The postoperative management of elderly patients with T4, N0–1, M0 non–small cell lung cancer (NSCLC) remains controversial. The objective of this study was to evaluate the association of adjuvant chemotherapy with survival and toxicity among these patients. Using surveillance, epidemiology and end results registry data linked to Medicare claims, we identified 389 elderly patients with resected T4, N0–1, M0 NSCLC diagnosed between 1992 and 2007. We compared survival of patients treated with and without platinum-based chemotherapy using a Cox regression adjusting for propensity scores for chemotherapy use and use of radiotherapy. We used logistic regression to assess the risk of adverse events in patients receiving chemotherapy. No benefit was noted in overall survival with adjuvant chemotherapy after PS adjustment for both N0 (hazard ratio 0.78, 95 % confidence interval 0.50–1.23) and N1 (hazard ratio 1.01, 95 % confidence interval 0.67–1.53) cancers. Patients receiving adjuvant chemotherapy experienced severe adverse events more frequently than patients who did not receive chemotherapy. Use of adjuvant chemotherapy in elderly patients with T4, N0–1, M0 NSCLC was not associated with a survival advantage and was associated with higher rates of severe toxicity.

Lymph node (LN) status is an important component of staging; it provides valuable prognostic information and influences treatment decisions. However, the prognostic significance of the number of positive LNs in N1 non-small cell lung cancer (NSCLC) remains unclear. In this study we evaluated whether a higher number of positive LNs results in worse survival among patients with N1 disease.The Surveillance, Epidemiology, and End Results database was used to identify 3,399 patients who underwent resection for N1 NSCLC. Subjects were categorized into groups based on the number of positive nodes: one, two to three, four to eight, and more than eight positive LNs. The prognostic significance of the number of positive LNs in relation to survival was evaluated using the Kaplan-Meier method. Stratified and Cox regression analysis were used to evaluate the relationship between the number of positive LNs and survival after adjusting for potential confounders.Unadjusted survival analysis showed that a greater number of N1 LNs was associated with worse lung cancer-specific (P.0001) and overall (P.0001) survival. Mean lung cancer-specific survival was 8.8, 8.2, 6.0, and 3.9 years for patients with one, two to three, four to eight, and more than eight positive LNs, respectively. Stratified and adjusted analysis also showed the number of N1 LNs was an independent predictor of survival after controlling for potential confounders.The number of positive LNs is an independent prognostic factor of survival in patients with N1 NSCLC. This information may be used to further stratify patients with respect to risk of recurrence in order to determine postoperative management.

383 Background: Pancreatic ductal adenocarcinoma (PDAC) remains highly lethal. Diabetes mellitus (DM) is both a risk factor for and a sequela of PDAC. Metformin, a commonly prescribed biguanide oral hypoglycemic used for the treatment of type II DM, has been found to have a chemo-protective role in PDAC in some in-vitro and human-based studies; conflicting literature exists regarding its potential role as a therapeutic agent. We investigated whether metformin use prior to PDAC diagnosis is associated with improved survival of patients with DM. Methods: We used the Surveillance, Epidemiology, and End-Results (SEER) linked Medicare database to identify diabetic patients with PDAC diagnosed between 2007-2011. Information regarding use of anti-hyperglycemic drugs prior to cancer diagnosis was extracted from Part D claims. The diabetic severity comorbidity index (DCSI) was used to control for DM severity. Logistic regression was used to calculate propensity scores for metformin use based on each patient’s sociodemographic characteristics, diabetic severity, and co-morbidity status. Inverse propensity weighted Cox Proportional-Hazard Models were subsequently used to assess the association between metformin use and overall survival adjusting for measured confounders. Results: We identified 1916 patients with PDAC and a diagnosis of DM on hypoglycemic medications at least one year prior to cancer diagnosis. Of these, 1098 (57.3%) were treated with metformin and 818 (42.7%) with other DM medications. Mean survival for those on metformin was 5.5 months compared with 4.2 months for those not on metformin (p < 0.01). After adjusting for confounders, patients on metformin had a 12% decreased risk of mortality compared to patients on other medications (hazard ratio [HR]: 0.88, 95% confidence interval [CI]: 0.81-0.96, P 2, DCSI 0-1 vs > 2, and for those treated with insulin vs other hypoglycemic medications (p < 0.01 for all). Conclusions: Metformin is associated with increased survival among diabetics with PDAC. If confirmed in prospective study, these results suggest a possible role for metformin use in diabetics with PDAC.