Thrombosis risk prediction in lymphoma patients: A multi-institutional, retrospective model development and validation study.

Venous thromboembolism (VTE) poses a significant risk to cancer patients receiving systemic therapy. The generalizability of pan-cancer models to lymphomas is limited. Currently, there are no reliable risk prediction models for thrombosis in patients with lymphoma. Our objective was to create a risk assessment model (RAM) specifically for lymphomas. We performed a retrospective cohort study to develop Fine and Gray sub-distribution hazard model for VTE and pulmonary embolism (PE)/ lower extremity deep vein thrombosis (LE-DVT) respectively in adult lymphoma patients from the Veterans Affairs national healthcare system (VA). External validations were performed at the Harris Health System (HHS) and the MD Anderson Cancer Center (MDACC). Time-dependent c-statistic and calibration curves were used to assess discrimination and fit. There were 10,313 (VA), 854 (HHS), and 1858 (MDACC) patients in the derivation and validation cohorts with diverse baseline. At 6 months, the VTE incidence was 5.8% (VA), 8.2% (HHS), and 8.8% (MDACC), respectively. The corresponding estimates for PE/LE-DVT were 3.9% (VA), 4.5% (HHS), and 3.7% (MDACC), respectively. The variables in the final RAM included lymphoma histology, body mass index, therapy type, recent hospitalization, history of VTE, history of paralysis/immobilization, and time to treatment initiation. The RAM had c-statistics of 0.68 in the derivation and 0.69 and 0.72 in the two external validation cohorts. The two models achieved a clear differentiation in risk stratification in each cohort. Our findings suggest that easy-to-implement, clinical-based model could be used to predict personalized VTE risk for lymphoma patients.

Personal history of cancer as a risk factor for second primary lung cancer: Implications for lung cancer screening.

BACKGROUND: Personal history of cancer is an independent risk factor for lung cancer but is omitted from existing lung cancer screening eligibility criteria. In this study, we assess the lung cancer risk among cancer survivors and discuss potential implications for screening. METHODS: This was a retrospective, secondary analysis of data from the Surveillance, Epidemiology and End Results (SEER) registry and the MD Anderson Cancer Center (MDACC). We estimated the standardized incidence ratios (SIRs) for lung cancer by site of first primary cancer using data from SEER. We assessed the lung cancer risk among head and neck cancer survivors from MDACC using cumulative incidence and compared the risk ratios (RR) by individuals' screening eligibility status. RESULTS: Other than first primary lung cancer (SIR: 5.10, 95% CI: 5.01-5.18), cancer survivors in SEER with personal history of head and neck cancer (SIR: 3.71, 95% CI: 3.63-3.80) had the highest risk of developing second primary lung cancer, followed by bladder (SIR: 1.86, 95% CI: 1.81-1.90) and esophageal cancers (SIR: 1.78, 95% CI: 1.61-1.96). Head and neck cancer survivors had higher risk to develop lung cancer compared to the National Lung Screening Trial's subjects, (781 vs. 572 per 100,000 person-years, respectively). Head and neck cancer survivors ineligible for lung cancer screening seen at MDACC had significantly higher lung cancer risk than head and neck cancer survivors from SEER (RR: 1.9, p < 0.001). CONCLUSION: Personal history of cancer, primarily head and neck cancer, is an independent risk factor for lung cancer and may be considered as an eligibility criterion in future lung cancer screening recommendations.

Incidence and Geographical Distribution of Adrenocortical Carcinoma: Retrospective Analysis of a State Cancer Registry.

OBJECTIVE: Adrenocortical carcinoma (ACC) is a rare malignancy without established association with environmental risk factors. ACC incidence is stable based on large surgical databases while referral centers data reported increasing number of cases seen. We studied ACC incidence and distribution at a county level to find potential ACC "hot spots" that could be linked to environmental exposures. METHODS: A retrospective analysis of Texas Cancer Registry that included ACC patients diagnosed between 2000 and 2018. County-level heatmaps were created and compared with breast, prostate, and lung cancer. RESULTS: We identified 448 ACC cases during the study period. Cases were registered in 110 of the 254 counties (43.3%) in Texas, representing 92.74% of the total population. The median incidence was 23 new cases/y (range 14-33). The mean population-adjusted ACC incidence rate was 0.104 per 100 000 per year (standard deviation 0.005; 95% CI, 0.092-0.116). Seven counties (6.3%) accounted for 215 (48.0%) cases, with more than 10 cases each and median standardized incidence ratio (SIR) of 0.1 (range, 0.0-0.9). One hundred three counties (93.7%) accounted for the remaining 233 cases (52%), with fewer than 10 cases per county. The highest standardized incidence ratios were found in counties with a median population of fewer than 14 000 residents and with only one reported case. CONCLUSION: Our analysis is the first report to create ACC heatmap and could not detect any geographic clustering of ACC in Texas. The incidence of ACC remained stable and consistent with data from other large databases.

External validation of a novel electronic risk score for cancer-associated thrombosis in a comprehensive cancer center.

Venous thromboembolism (VTE) is a significant complication for cancer patients undergoing systemic therapy. We performed an independent external validation for a recently derived and validated a novel electronic health record (EHR) VTE risk score in a comprehensive cancer center. Adult patients with incident cancer diagnoses were identified from MD Anderson Cancer Center Tumor Registry 1/2017-1/2021. Baseline covariates extracted at the time of first-line systemic therapy included demographics, cancer site/histology, stage, treatment, complete blood count, body mass index, recent prolonged hospitalization, and history of VTE or paralysis. VTE was ascertained using an institution-specific natural language processing radiology algorithm (positive predictive value of 94.8%). The median follow-up for 21 142 cancer patients was 8.1 months. There were 1067 (5.7%) VTE within 6 months after systemic therapy. The distribution of the novel score for 0-, 1, 2, 3, 4, 5+ was 5661, 3558, 3462, 3489, 2918, and 2054; while the corresponding 6-month VTE incidence was 1.3%, 3.1%, 5.4%, 7.3%, 9.3%, and 13.8%, respectively (c statistic 0.71 [95% CI 0.69-0.72] with excellent calibration). In comparison, the Khorana score had a c statistic of 0.64 [95% CI 0.62-0.65]. The two risk scores had 80% concordance; the novel score reclassified 20% of Khorana score (3530 low-to-high with 9.0% VTE; 734 high-to-low with 3.4% VTE) and led to a 25% increment in VTEs captured in the high-risk group. In conclusion, the novel score demonstrated consistent discrimination and calibration across cohorts with heterogenous demographics. It could become a new standard to select high-risk populations for clinical trials and VTE monitoring.

Cancer Patient Acceptance of HIV Screening at a Large Tertiary Cancer Center.

The U.S. Centers for Disease Control and Prevention (CDC), the U.S. Preventive Services Task Force (USPSTF) and the National Comprehensive Cancer Network (NCCN) recommend offering HIV testing for patients presenting for cancer care. Not recognizing and treating HIV infection adversely impacts both cancer treatment and HIV outcomes. Acceptance rates of oncology patients for HIV screening are not known. Our tertiary cancer center inserted language requesting permission to screen for HIV infection into the consent forms for initial presentation for cancer care. Willingness to undergo testing was examined in 29,549 consecutive new patients. These were analyzed by gender and age. Overall, 80.9% of patients agreed to HIV screening. Incorporation of language requesting permission for HIV screening into the consent form provided at presentation for cancer care, relieves clinicians from adding this task.

Evolution of the Cancer Registrar in the Era of Informatics.

The cancer registrar reports accurate, complete, and timely abstracted cancer data to various healthcare agencies. The data are used for understanding the incidence of cancer, evaluating the effectiveness of public health efforts in the prevention of new cases and improving patient care outcomes and survival. There are increasing demands placed on registrars for additional data points with real-time submission to reporting agencies. To that end, registrars are increasing the use of informatics to meet the demand. The purpose of this article is the role of the registrar in the collection and reporting of critical cancer data and how registrars are currently using informatics to enhance their work. This article describes how informatics can be leveraged in the future and how registrars play a vital role in meeting the increasing demands placed on them to provide timely, meaningful, and accurate data for the cancer community.

Origin of Subsequent Malignant Neoplasms in Patients with History of Testicular Germ Cell Tumor.

Although genetic changes may be pivotal in the origin of cancer, cellular context is paramount. This is particularly relevant in a progenitor germ cell tumor and its differentiated mature teratoma counterpart when it concerns tumor heterogeneity and cancer dormancy in subsequent second malignancies (subsequent malignant neoplasms (SMNs)). From our tumor registry database, we identified 655 testicular germ cell tumor (TGCT) patients who developed SMNs between January 1990 and September 2018. Of the 113 solid organ SMNs, 42 had sufficient tumor tissue available for fluorescence in situ hybridization (FISH) analysis of isochromosome 12p [i(12p)]. We identified seven additional patients for targeted DNA and RNA sequencing of teratomas and adjacent somatic transformation. Finally, we established cell lines from freshly resected post-chemotherapy teratomas and evaluated the cells for stemness expression by flow cytometry and by the formation of teratomas in a xenograft model. In our cohort, SMNs comprising non-germ cell tumors occurred about 18 years after a diagnosis of TGCT. Of the 42 SMNs examined, 5 (12%) contained i(12p) and 16 (38%) had 12p gain. When comparing a teratoma and adjacent somatic transformation, targeted DNA and RNA sequencing demonstrated high concordance. Studies of post-chemotherapy teratoma-derived cell lines revealed cancer-initiating cells expressing multipotency as well as early differentiation markers. For the first time, we demonstrated the prevalence of i(12p) in SMNs and the presence of progenitor cells embedded within mature teratomas after chemotherapy. Our findings suggest a progenitor stem-like cell of origin in SMN and TGCT and highlight the importance of cellular context in this disease.

Presenting Symptoms in the Emergency Department as Predictors of Intensive Care Unit Admissions and Hospital Mortality in a Comprehensive Cancer Center.

PURPOSE: The identification of patients at high risk for poor outcomes may allow for earlier palliative care and prevent futile interventions. We examined the association of presenting symptoms on risk of intensive care unit (ICU) admission and hospital death among patients with cancer admitted through an emergency department (ED). METHODS: We queried MD Anderson Cancer Center databases for all patients who visited the ED in 2010. Presenting symptoms, ICU admissions, and hospital deaths were reviewed; patient data analyzed; and risk factors for ICU admission and hospital mortality identified. RESULTS: The main presenting symptoms were pain, fever, and respiratory distress. Of the patients with cancer who visited the ED, 5,362 (58%) were admitted to the hospital at least once (range, 1 to 13 admissions), 697 (13%) were admitted to the ICU at least once, and 587 (11%) died during hospitalization (31% of 233 patients with hematologic malignancies and 27% of 354 patients with solid tumors died in the ICU; P < .001). In multivariable logistic regression, presenting symptoms of respiratory distress or altered mental status; lung cancer, leukemia, or lymphoma; and nonwhite race were independent predictors of hospital death. Patients who died had a longer median length of hospital stay than patients discharged alive (14 v 6 days for hematologic malignancies and 7 v 5 days for solid tumors; P < .001). CONCLUSION: Patients with cancer admitted through an ED experience high ICU admission and hospital mortality rates. Patients with advanced cancer and respiratory distress or altered mental status may benefit from palliative care that avoids unnecessary interventions.

2013 HIPAA Changes Provide Opportunities and Challenges for Researchers: Perspectives from a Cancer Center.

In 2013, the U.S. Department of Health and Human Services modified the Health Insurance Portability and Accountability Act Privacy Rule to "strengthen privacy and security protections" while "improving workability and effectiveness to increase flexibility for and decrease burden on regulated entities." In this article, we attempt to translate these generalized goals into the real-world implications of these changes. Under the new rules, researchers can obtain participants' permission to use their protected health information for more research activities with a single, upfront authorization (thereby reducing paperwork for participants, researchers, and institutional review boards) while providing potential participants with more information upon which to base their decisions about participation. The combined authorizations can be used in clinical trials and their optional substudies and in stand-alone biospecimen-banking research that includes authorization to permit future research use. We also suggest best practices for taking advantage of the flexibility offered by the new rules while maintaining strong privacy protections for human subjects.

Survival patterns in squamous cell carcinoma of the head and neck: pain as an independent prognostic factor for survival.

UNLABELLED: Survival outcomes in patients with squamous cell carcinoma of the head and neck (HNSCC) vary by extent of disease, behavioral factors, and socioeconomic factors. We assessed the extent to which pretreatment pain influences survival in 2,340 newly diagnosed patients with HNSCC, adjusting for disease stage, symptoms, pain medications, comorbidities, smoking, alcohol consumption, age, sex, and race/ethnicity. Patients rated their pain at presentation to the cancer center (0 = "no pain" and 10 = "pain as bad as you can imagine"). Survival time was calculated from the date of diagnosis to the date of death of any cause or last follow-up. Five-year overall survival was calculated for all the variables assessed in the study. Severe pain (≥7) was most prevalent among those with oral cancer (20.4%; pharynx = 18.8%; larynx = 16.1%) and significantly varied by tumor stage, fatigue severity, smoking status, comorbid lung disease, and race (all P < .05) across cancer diagnoses. Overall 5-year survival varied by pain for oral (severe pain = 31% vs nonsevere pain = 52%; P < .001) and pharyngeal cancer (severe pain = 33% vs nonsevere pain = 53%; P < .001). Multivariable analyses showed that pain persisted as an independent prognostic factor for survival. Pain reported prior to treatment should be considered in understanding survival outcomes in HNSCC patients. PERSPECTIVE: Pretreatment pain was an independent predictor of survival in a large sample of HNSCC patients even after accounting for tumor node metastasis stage, fatigue, age, race/ethnicity, smoking, and alcohol intake. Therefore, symptoms at presentation and before cancer treatment are important factors to be considered in understanding survival outcomes in HNSCC patients.

Low tissue oxygen saturation at emergency center triage is predictive of intensive care unit admission.

PURPOSE: Timely recognition of critical patients by emergency center triage is an ongoing challenge. Peripheral tissue oxygen saturation (StO2) measurement has been used to monitor shock patients' responses to resuscitation. Interest has developed in evaluating StO2 as a triage tool, but limited studies have addressed critically ill patients. MATERIAL AND METHODS: This is a single-center, retrospective study of 158 emergent cancer patients with hypotension and/or modified systemic inflammatory response syndrome who underwent StO2 spot measurement at triage. RESULTS: Of the 57 patients with StO2 less than 70%, 17 went to the intensive care unit (ICU), whereas only 14 of the 101 patients with StO2 of 70% to 89% (P = .01) went to the ICU. There was no significant difference in non-ICU hospital admission or mortality between the 2 groups. The odds ratio of ICU admission for patients with StO2 less than 70% relative to those with StO2 of 70% to 89% was 2.64 (95% confidence interval, 1.18-5.87) and 2.87 (95% confidence interval, 1.23-6.66) when adjusted for mean arterial pressure, pulse, and temperature. CONCLUSIONS: In this patient population, an StO2 less than 70% significantly increased the risk of ICU admission. Tissue oxygen saturation at triage identifies critical patients who may not be recognized by vital signs alone. Tissue oxygen saturation measurement could help providers make earlier decisions regarding hospital resource allocation.

Initial medical attention on patients with early-stage non-small cell lung cancer.

BACKGROUND: Detection of early stage non-small cell lung cancer (NSCLC) is commonly believed to be incidental. Understanding the reasons that caused initial detection of these patients is important for early diagnosis. However, these reasons are not well studied. METHODS: We retrospectively reviewed medical records of patients diagnosed with stage I or II NSCLC between 2000 and 2009 at UT MD Anderson Cancer Center. Information on suggestive LC-symptoms or other reasons that caused detection were extracted from patients' medical records. We applied univariate and multivariate analyses to evaluate the association of suggestive LC-symptoms with tumor size and patient survival. RESULTS: Of the 1396 early stage LC patients, 733 (52.5%) presented with suggestive LC-symptoms as chief complaint. 347 (24.9%) and 287 (20.6%) were diagnosed because of regular check-ups and evaluations for other diseases, respectively. The proportion of suggestive LC-symptom-caused detection had a linear relationship with the tumor size (correlation 0.96; with p<.0001). After age, gender, race, smoking status, therapy, and stage adjustment, the symptom-caused detection showed no significant difference in overall and LC-specific survival when compared with the other (non-symptom-caused) detection. CONCLUSION: Symptoms suggestive of LC are the number one reason that led to detection in early NSCLC. They were also associated with tumor size at diagnosis, suggesting early stage LC patients are developing symptoms. Presence of symptoms in early stages did not compromise survival. A symptom-based alerting system or guidelines may be worth of further study to benefit NSCLC high risk individuals.

DNA repair capacity in peripheral lymphocytes predicts survival of patients with non-small-cell lung cancer treated with first-line platinum-based chemotherapy.

PURPOSE: Platinum-based regimens are the standard chemotherapy for patients with advanced non-small-cell lung cancer (NSCLC). DNA repair capacity (DRC) in tumor cells plays an important role in resistance to platinum-based drugs. We have previously reported that efficient DRC, as assessed by an in vitro lymphocyte-based assay, was a determinant of poor survival in patients with NSCLC in a relatively small data set. In this larger independent study of 591 patients with NSCLC, we further evaluated whether DRC in peripheral lymphocytes predicts survival of patients with NSCLC who receive platinum-based chemotherapy. PATIENTS AND METHODS: All patients were recruited at The University of Texas MD Anderson Cancer Center and donated blood samples before the start of any chemotherapy. We measured DRC in cultured T lymphocytes by using the host-cell reactivation assay, and we assessed associations between DRC in peripheral lymphocytes and survival of patients with NSCLC who were treated with first-line platinum-based chemotherapy. RESULTS: We found an inverse association between DRC in peripheral lymphocytes and patient survival. Compared with patients in the low tertile of DRC, patients with NSCLC in the high tertile of DRC had significantly worse overall and 3-year survival (adjusted hazard ratio [HR], 1.33; 95% CI, 1.04 to 1.71; P = .023; and HR, 1.35; 95% CI, 1.04 to 1.76; P = .025, respectively). This trend was more pronounced in patients with early-stage tumors, adenocarcinoma, or squamous cell carcinoma. CONCLUSION: We confirmed that DRC in peripheral lymphocytes is an independent predictor of survival for patients with NSCLC treated with platinum-based chemotherapy.

Association of smoking with tumor size at diagnosis in non-small cell lung cancer.

Tumor size at diagnosis (TSD) indirectly reflects tumor growth rate. The relationship between TSD and smoking is poorly understood. The aim of the study was to determine the relationship between smoking and TSD. We reviewed 1712 newly diagnosed and previously untreated non-small cell lung cancer (NSCLC) patients' electronic medical records and collected tumor characteristics. Demographic and epidemiologic characteristics were derived from questionnaires administered during personal interviews. Univariate and multivariate linear regression models were used to evaluate the relationship between TSD and smoking controlling for demographic and clinical factors. We also investigated the relationship between the rs1051730 SNP in an intron of the CHRNA3 gene (the polymorphism most significantly associated with lung cancer risk and smoking behavior) and TSD. We found a strong dose dependent relationship between TSD and smoking. Current smokers had largest and never smokers smallest TSD with former smokers having intermediate TSD. In the multivariate linear regression model, smoking status (never, former, and current), histological type (adenocarcinoma versus SqCC), and gender were significant predictors of TSD. Smoking duration and intensity may explain the gender effect in predicting TSD. We found that the variant allele of rs1051730 in CHRNA3 gene was associated with larger TSD of squamous cell carcinoma. In the multivariate linear regression model, both rs1051730 and smoking were significant predictors for the size of squamous carcinomas. We conclude that smoking is positively associated with lung tumor size at the moment of diagnosis.

Genetic variants of p21 and p27 and pancreatic cancer risk in non-Hispanic Whites: a case-control study.

OBJECTIVES: p21 (WAF1/Cip1/CDKN1A) and p27 (Kip1/CDKN1B) are members of the Cip/Kip family of cyclin-dependent kinase inhibitors, which can induce cell cycle arrest and serve as tumor suppressors. We hypothesized that genetic variants in p21 and p27 may modify individual susceptibility to pancreatic cancer. METHODS: To test this hypothesis, we evaluated the associations of the Ser31Arg polymorphism in p21 and the Gly109Val polymorphism in p27, and their combinations, with pancreatic cancer risk in a case-control study of 509 pathologically confirmed pancreatic adenocarcinoma patients and 462 age- and sex-matched cancer-free controls in non-Hispanic whites. RESULTS: We found that the heterozygous and homozygous variant genotypes combined in a dominant model of the p21 polymorphism were associated with increased risk of pancreatic cancer compared with the homozygous wild type (adjusted odds ratio [ORadjusted], 1.70; 95% confidence interval [CI], 1.13-2.55). This increased risk was more pronounced in carriers with the p27 homozygous wild type (ORadjusted, 2.20; 95% CI, 1.32-3.68) and in nonsmokers (ORadjusted, 2.16; 95% CI, 1.14-4.10), although the p27 polymorphism alone was not associated with pancreatic cancer risk. CONCLUSIONS: These results indicate that the p21 polymorphism may contribute to susceptibility to pancreatic cancer, particularly among p27 homozygous wild-type carriers and nonsmokers.

Surgically managed lymph node-positive prostate cancer: does delaying hormonal therapy worsen the outcome?

OBJECTIVES: To review our experience with the surgical management of lymph node-positive prostate cancer and to determine if there is a benefit to treating such patients with immediate rather than delayed hormonal therapy (HT). PATIENTS AND METHODS: A retrospective analysis from January 1982 to January 2001 identified 100 patients treated by radical retropubic prostatectomy (RP) either alone (70, 23 later received delayed HT) or combined with adjuvant (immediate) HT (30), with the overall median follow-up being 5.2 years. RESULTS: The median patient age at diagnosis was 58.7 years, with 20% having clinical T3 disease, and the median prostate specific antigen (PSA) level at presentation was 10 ng/mL. In 41% of patients the Gleason score on prostatic biopsy was > or = 8. After RP, 30 patients received immediate HT used as an adjuvant after surgery in the absence of any evidence of disease progression, whereas 23 received delayed HT the use of which was provoked secondary to biochemical failure (PSA threshold of 0.2-5.0 ng/mL) with no evidence of metastatic disease. A comparison of the clinical variables between the groups showed a higher median PSA level at diagnosis (P = 0.027) and biopsy Gleason score (P = 0.052) in the delayed HT group. The immediate and delayed HT groups had similar metastatic-free (P = 0.549), disease-specific (P = 0.843) and overall survival (P = 0.843). Overall, biochemical failure developed in half the patients and distant metastasis in 13%, with only nine patients dying from disease. CONCLUSIONS: Immediate and delayed HT provide similar treatment outcomes in patients with surgically managed lymph node-positive prostate cancer.

Inadequacies of the current American Joint Committee on cancer staging system for prostate cancer.

BACKGROUND: Two major objectives of the American Joint Committee on Cancer (AJCC) staging system are to ensure appropriate treatments for patients and to determine prognosis. AJCC stage for distant prostate cancer includes patients with regional lymph node involvement. In the current study, the authors assessed whether patients with lymph node involvement and patients with distant metastasis, as determined using the Surveillance, Epidemiology, and End Results (SEER) staging system, had similar treatment and survival duration and, thus, were grouped together appropriately in the AJCC system. METHODS: In total, 4141 patients were selected from The University of Texas M. D. Anderson Cancer Center's Tumor Registry who initially had registered at the center between January 1, 1982, and December 31, 2001, with a diagnosis of prostate cancer; had received no treatment before presentation; and had received treatment at the center. Patients with unknown stage and patients with any other primary malignancies were excluded. Descriptive analyses of demographic and disease variables were performed. Using SEER stage groups, survival analyses and Cox proportional hazards regression analyses were performed. RESULTS: Treatments differed between patients with lymph node involvement and patients with distant metastasis. The median survival was 134 months for patients with lymph node involvement and 42 months for patients with distant metastasis. When these 2 groups were combined, as in the AJCC scheme, the median survival was 86 months. CONCLUSIONS: The treatment and median survival of patients with lymph node involvement differed substantially from those of patients with distant metastasis. The current AJCC scheme for prostate cancer appeared to be inappropriate when considering its purpose, and the authors concluded that it should be revised.

Incidence of major pulmonary morbidity after pneumonectomy: association with timing of smoking cessation.

BACKGROUND: The prevention of major pulmonary events (MPEs) after pneumonectomy may minimize postoperative mortality rates. The purpose of this study was to identify preoperative and perioperative factors associated with the development of MPEs after pneumonectomy to help predict which patients are at increased risk for MPEs. METHODS: We retrospectively reviewed the medical records of all patients (n = 261) who underwent pneumonectomies between January 1990 and May 1999. We analyzed preoperative and perioperative risk factors, the primary end point of an MPE and the secondary end points of mortality (in-hospital or 30 days postprocedure), length of stay, and hospital charges. A postoperative MPE included only pneumonia or acute respiratory distress syndrome as defined by the Centers for Disease Control and the American and European Consensus Conference's established criteria. Simple atelectasis that did not progress to pneumonia or a documented aspiration was not included. RESULTS: Four patients died within 12 hours of operation; the records of the remaining 257 patients were analyzed. An MPE occurred in 33 (12.8%) of 257 patients; 16 (6.2%) of 257 patients died. A multivariate analysis performed on relevant variables showed that only the timing of smoking cessation (1 month or sooner before operation) was a significant predictor of an MPE. Age, side of pneumonectomy, and the use of preoperative chemotherapy or combined chemotherapy and radiation therapy were not significant predictors of an MPE. An MPE significantly increased the mortality rate 2.1% versus 39.3%, p < 0.001). CONCLUSIONS: Mortality after pneumonectomy increased significantly with the development of an MPE. Patients who continue to smoke within 1 month of operation are at an increased risk for developing an MPE. Interventions to minimize MPEs may minimize the mortality rate after pneumonectomy.