Avoiding lead-time bias by estimating stage-specific proportions of cancer and non-cancer deaths.

PURPOSE: Understanding how stage at cancer diagnosis influences cause of death, an endpoint that is not susceptible to lead-time bias, can inform population-level outcomes of cancer screening. METHODS: Using data from 17 US Surveillance, Epidemiology, and End Results registries for 1,154,515 persons aged 50-84 years at cancer diagnosis in 2006-2010, we evaluated proportional causes of death by cancer type and uniformly classified stage, following or extrapolating all patients until death through 2020. RESULTS: Most cancer patients diagnosed at stages I-II did not go on to die from their index cancer, whereas most patients diagnosed at stage IV did. For patients diagnosed with any cancer at stages I-II, an estimated 26% of deaths were due to the index cancer, 63% due to non-cancer causes, and 12% due to a subsequent primary (non-index) cancer. In contrast, for patients diagnosed with any stage IV cancer, 85% of deaths were attributed to the index cancer, with 13% non-cancer and 2% non-index-cancer deaths. Index cancer mortality from stages I-II cancer was proportionally lowest for thyroid, melanoma, uterus, prostate, and breast, and highest for pancreas, liver, esophagus, lung, and stomach. CONCLUSION: Across all cancer types, the percentage of patients who went on to die from their cancer was over three times greater when the cancer was diagnosed at stage IV than stages I-II. As mortality patterns are not influenced by lead-time bias, these data suggest that earlier detection is likely to improve outcomes across cancer types, including those currently unscreened.

Variation in patterns of second primary malignancies across U.S. race and ethnicity groups: a Surveillance, Epidemiology, and End Results (SEER) analysis.

PURPOSE: One in six incident cancers in the U.S. is a second primary cancer (SPC). Although primary cancers vary considerably by race and ethnicity, little is known about the population-based occurrence of SPC across these groups. METHODS: Using Surveillance, Epidemiology, and End Results (SEER) 12 data and relative to the general population, we calculated standardized incidence ratios (SIRs) and 95% confidence intervals (CIs) for SPC among 2,457,756 Hispanics, non-Hispanic Asian American/Pacific Islanders (NHAAPI), non-Hispanic black (NHB), and non-Hispanic whites (NHW) cancer survivors aged 45 years or older when diagnosed with a first primary cancer (FPC) from 1992 to 2015. RESULTS: The risk of second primary bladder cancer after first primary prostate cancer was higher than expected in Hispanic (SIR = 1.18, 95% CI: 1.01-1.38) and NHAAPI (SIR = 1.41, 95% CI: 1.20-1.65) men than NHB and NHW men. Among women with a primary breast cancer, Hispanic, NHAAPI, and NHB women had a nearly 1.5-fold higher risk of a second primary breast cancer, while NHW women had a 6% lower risk. Among men with prostate cancer whose SPC was diagnosed 2 to <12 months, NHB men were at higher risk for colorectal cancer and Hispanic and NHW men for non-Hodgkin's lymphoma. In the same time frame for breast cancer survivors, Hispanic and NHAAPI women were significantly more likely than NHB and NHW women to be diagnosed with a second primary lung cancer. CONCLUSION: Future studies of SPC should investigate the role of shared etiologies, stage of diagnosis, treatment, and lifestyle factors after cancer survival across different racial and ethnic populations.

Key risk factors for the relative and absolute 5-year risk of cancer to enhance cancer screening and prevention.

BACKGROUND: This study identifies populations who may benefit most from expanded cancer screening. METHODS: Two American Cancer Society prospective cohort studies, Cancer Prevention Study-II Nutrition Cohort and Cancer Prevention Study-3, were used to identify the risk factors associated with a > 2% absolute risk of any cancer within 5 years. In total, 429,991 participants with no prior personal history of cancer were followed for cancer for up to 5 years. Multivariable Cox proportional hazards models were used to estimate hazard ratios and 95% confidence intervals for association. By using these hazard ratios, individualized coherent absolute risk estimation was used to calculate absolute risks by age. RESULTS: Overall, 15,226 invasive cancers were diagnosed among participants within 5 years of enrollment. The multivariable-adjusted relative risk of any cancer was strongest for current smokers compared with never-smokers. In men, alcohol intake, family history of cancer, red meat consumption, and physical inactivity were also associated with risk (p < .05). In women, body mass index, type 2 diabetes, hysterectomy, parity, family history of cancer, hypertension, tubal ligation, and physical inactivity were associated (p < .05). The absolute 5-year risk exceeded 2% among nearly all participants older than 50 years and among some participants younger than 50 years, including current or former smokers (<30 years since quitting) and long-term nonsmokers with a body mass index >25 kg/m2 or a first-degree family history of cancer. The absolute 5-year risk was as high as 29% in men and 25% in women. CONCLUSIONS: Older age and smoking were the two most important risk factors associated with the relative and absolute 5-year risk of developing any cancer.

Anaplastic large cell lymphoma in human immunodeficiency virus-infected people and solid organ transplant recipients.

Human immunodeficiency virus (HIV)-infected people and solid organ transplant recipients have elevated risk of anaplastic large cell lymphoma (ALCL). Little is known regarding ALCL risk factors in immunosuppressed populations. We used data from US cancer registries linked to HIV registries (1996-2016) and to the national transplant registry (1992-2017). ALCL risk in HIV-infected people and transplant recipients relative to the general population was calculated as a standardized incidence ratio (SIR). ALCL risk factors were evaluated using Poisson regression. We identified 121 incident ALCL cases in the HIV (n = 86) and transplant (n = 35) populations. We reviewed pathology reports for 45 cases and most (86·7%) were confirmed as ALCL. Epstein-Barr virus tested positive in 1/8 (12·5%) cases. Compared to the general population, ALCL risk was strongly elevated among HIV-infected people [SIR 5·43; 95% confidence interval (CI) 4·27-6·81] and transplant recipients (5·96; 4·03-8·49). Among HIV-infected people, ALCL incidence was strongly related to CD4 count [adjusted incidence rate ratio (aIRR) 0·15 for ≥500 vs. <200 cells/µl; P trend < 0·001]. Among transplant recipients, risk was highest within the first year (aIRR 6·82) and 10+ years post-transplant (5·99). In conclusion, ALCL risk is strongly increased in these immunosuppressed populations but may be unrelated to EBV infection based on limited reports.

Magnitude of reduction in risk of second contralateral breast cancer with bilateral mastectomy in patients with breast cancer: Data from California, 1998 through 2015.

BACKGROUND: Increasingly, patients with breast cancer undergo bilateral mastectomy (BLM). To the authors' knowledge, the magnitude of benefit is unknown. METHODS: The authors used data from the Surveillance, Epidemiology, and End Results (SEER) program regarding all women diagnosed with American Joint Committee on Cancer stage 0 to stage III unilateral breast cancer in California from 1998 through 2015 and treated with BLM versus breast-conserving therapy including surgery and radiotherapy (BCT) or unilateral mastectomy (ULM). The authors measured relative risks of second contralateral breast cancer (CBC) and breast cancer death using Fine and Gray multivariable regression modeling adjusted for the competing risk of death and death from another cause, respectively, and potential confounding factors. Absolute excess risk of CBC was measured as the observed minus expected number of breast cancers in the general population divided by 10,000 person-years at risk. RESULTS: Among 245,418 patients with a median follow-up of 6.7 years, 7784 patients (3.2%) developed CBC. Relative risks were lower after BLM (hazard ratio [HR], 0.10; 95% CI, 0.07-0.14) and higher after ULM (HR, 1.07; 95% CI, 1.02-1.13) versus BCT. Absolute excess risks were higher after BCT and ULM (5.0 and 13.6 more cases, respectively) compared with BLM (28.6 fewer cases). BLM reduced risk more among older women (38.0 fewer cases for women aged ≥50 years vs 17.9 fewer cases among women aged <50 years) but provided similar risk reduction across categories of tumor grade and tumor hormone receptor status. Compared with BCT, the risk of breast cancer death was equivalent after BLM (HR, 1.03; 95% CI, 0.96-1.11) and higher after ULM (HR, 1.21; 95% CI, 1.17-1.25). CONCLUSIONS: BLM may reduce second breast cancer risk by 34 to 43 cases per 10,000 person-years compared with other surgical procedures, but is not associated with a lower risk of death. Second breast cancers are rare, and their reduction should be weighed against the harms associated with BLM.

Risk of Kaposi sarcoma after solid organ transplantation in the United States.

Due to treatment with immunosuppressive medications, solid organ transplant recipients have elevated risk for Kaposi sarcoma (KS), which is caused by human herpesvirus 8 (HHV8). Other risk factors for KS are poorly understood. We linked the United States solid organ transplant registry with 17 population-based cancer registries to ascertain KS incidence among 244,964 transplant recipients from 1987-2014. To compare incidence rates of KS according to patient and transplant characteristics, we calculated incidence rate ratios (IRRs) using Poisson regression. To compare associations of KS with other skin cancers occurring before or within 12 months of KS diagnosis, we computed odds ratios (ORs) and 95% confidence intervals (CIs) using conditional logistic regression. All statistical tests were two-sided. We identified 163 KS cases during follow-up. Among transplant recipients, we found significantly increased risk of KS associated with male sex (IRR = 1.87; 95%CI:1.32,2.71), nonwhite race (IRR = 2.67; 95%CI:1.92,3.72), non-US citizenship (IRR = 2.10; 95%CI:1.19,3.47), lung transplant (IRR = 2.22; 95%CI:1.03,4.24, vs. kidney), and older age at transplant. KS risk decreased significantly with time since transplant and recent calendar year, however, no specific induction or maintenance medication was associated with KS. KS incidence was not significantly associated with ambient ultraviolet radiation (IRR = 1.32 95%CI:0.87,2.02, tertile 3 vs. 1). KS incidence has decreased in recent calendar years. In a cross-sectional sample, we found cutaneous squamous cell carcinoma was associated with KS (OR = 4.83; 95%CI:1.30,14.69). KS risk factors included those potentially associated with HHV8 infection and increased immunosuppression. Our findings suggest that transplant recipients with a non-KS skin cancer may also be at high KS risk.

Risk of oral tongue cancer among immunocompromised transplant recipients and human immunodeficiency virus-infected individuals in the United States.

BACKGROUND: Oral tongue cancer incidence has increased among whites in the United States; however, the cause remains unknown. If an infectious agent is implicated, then elevated risk would be expected among immunosuppressed individuals. METHODS: By using population-based registry linkage information from the US Transplant Cancer Match and human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) Cancer Match studies, the authors examined the risk of oral tongue squamous cell carcinoma (SCC) among immunocompromised transplantation recipients and HIV-infected individuals. In addition, the risks of oropharyngeal SCC (strongly related to human papillomavirus infection; modestly affected by immunosuppression), other tobacco/alcohol-related oral cavity SCCs (not thought to be infection/immunosuppression-related), and non-Hodgkin lymphoma of oral cavity/pharynx (strongly related to Epstein-Barr virus; profoundly affected by immunosuppression) were evaluated. RESULTS: Compared with the general population, the risk of non-Hodgkin lymphoma was strongly increased (standardized incidence ratio [SIR] > 8.0). The risk of all SCCs was modestly and similarly elevated among transplantation recipients (SIR range, 2.2-2.7; Pheterogeneity = .2); whereas, among HIV-infected individuals, the risk of oral tongue SCC was higher compared with the risk of other SCCs (SIR, 3.0 vs 1.7 [for oropharyngeal SCCs] and 2.3 [for other oral cavity SCCs]; Pheterogeneity < .001). The risk of SCCs was significantly higher among men, older individuals, and whites; and risk increased with the time since transplantation/AIDS onset. The risk of oral tongue SCC was significantly higher among HIV-infected men who have sex with men compared with the average risk in HIV-infected individuals (adjusted incidence rate ratio = 2.0). CONCLUSIONS: Similar modest increases in the risk of oral tongue and other oral cavity SCCs do not suggest that an infectious agent or exposure profoundly affected by immunosuppression underlies the increase in oral tongue cancer. Cancer 2018;124:2515-22. © 2018 American Cancer Society.

Characterizing the neighborhood obesogenic environment in the Multiethnic Cohort: a multi-level infrastructure for cancer health disparities research.

PURPOSE: We characterized the neighborhood obesogenic environment in the Multiethnic Cohort (MEC) by examining the associations of obesity with attributes of the social and built environment, establishing a multi-level infrastructure for future cancer research. METHODS: For 102,906 African American, Japanese American, Latino, and white MEC participants residing predominately in Los Angeles County, baseline residential addresses (1993-1996) were linked to census and geospatial data, capturing neighborhood socioeconomic status (nSES), population density, commuting, food outlets, amenities, walkability, and traffic density. We examined neighborhood attributes and obesity (body mass index ≥ 30 kg/m2) associations using multinomial logistic regression, adjusting for individual-level (e.g., demographics, physical activity, and diet) and neighborhood-level factors. RESULTS: NSES was associated with obesity among African Americans, Latinos, and whites (p-trend ≤ 0.02), with twofold higher odds (adjusted odds ratios, 95% confidence intervals) for living in the lowest versus highest quintile among African American women (2.07, 1.62-2.65), white men (2.11, 1.29-3.44), and white women (2.50, 1.73-3.61). Lower density of businesses among African American and white women and lower traffic density among white men were also associated with obesity (p-trends ≤ 0.02). CONCLUSIONS: Our study highlights differential impacts of neighborhood factors across racial/ethnic groups and establishes the foundation for multi-level studies of the neighborhood context and obesity-related cancers.

Pediatric neuro-oncology survival disparities in California.

The objective of this study was to investigate racial/ethnic differences in survival for pediatric high-grade glioma (HGG) and medulloblastoma in the state of California. We obtained data from the California Cancer Registry on 552 high-grade glioma patients (110 brainstem, 442 non-brainstem) and 648 medulloblastoma patients ages 0-19 years from 1988 to 2012. Using multivariate Cox proportional hazards regression, we examined the impact of individual and neighborhood characteristics on survival. Socioeconomic quintile and insurance status differed significantly by race for both diagnoses. Hispanic children with non-brainstem HGG had worse survival than non-Hispanic white children: hazard ratio (HR) 1.62; 95% confidence interval (CI) 1.24-2.11, but the difference was mitigated some by accounting for socioeconomic status (HR 1.48, CI 1.10-1.99). Racial/ethnic differences in survival exist for children with high-grade glioma, particularly Hispanic children with non-brainstem high-grade glioma, and are likely related to sociologic factors.

Regular and low-dose aspirin, other non-steroidal anti-inflammatory medications and prospective risk of HER2-defined breast cancer: the California Teachers Study.

BACKGROUND: Regular users of aspirin may have reduced risk of breast cancer. Few studies have addressed whether risk reduction pertains to specific breast cancer subtypes defined jointly by hormone receptor (estrogen and progesterone receptor) and human epidermal growth factor receptor 2 (HER2) expression. This study assessed the prospective risk of breast cancer (overall and by subtype) according to use of aspirin and other non-steroidal anti-inflammatory medications (NSAIDs) in a cohort of female public school professionals in California. METHODS: In 1995 - 1996, participants in the California Teachers Study completed a baseline questionnaire on family history of cancer and other conditions, use of NSAIDs, menstrual and reproductive history, self-reported weight and height, living environment, diet, alcohol use, and physical activity. In 2005-2006, 57,164 participants provided some updated information, including use of NSAIDs and 1457 of these participants developed invasive breast cancer before January 2013. Multivariable Cox proportional hazards regression models provided hazard rate ratios (HRR) for the association between NSAID use and risk of invasive breast cancer as well as hormone receptor- and HER2-defined subtypes. RESULTS: Developing breast cancer was associated inversely with taking three or more tablets of low-dose aspirin per week (23% of participants). Among women reporting this exposure, the HRR was 0.84 (95% confidence interval (CI) 0.72-0.98) compared to those not taking NSAIDs and this was particularly evident in women with the hormone receptor-positive/HER2-negative subtype (HRR = 0.80, 95% CI 0.66-0.96). Use of three or more tablets of "other" NSAIDs was marginally associated with lower risk of breast cancer (HRR = 0.79, 95% CI 0.62-1.00). Other associations with NSAIDs were generally null. CONCLUSION: Our observation of reduced risk of breast cancer, among participants who took three or more tablets of low-dose aspirin weekly, is consistent with other reports looking at aspirin without differentiation by dose. This is the first report to suggest that the reduction in risk occurs for low-dose aspirin and not for regular-dose aspirin and only among women with the hormone receptor-positive/HER2-negative subtype. This preliminary study builds on previous knowledge and further supports the need for formal cancer chemoprevention studies of low-dose aspirin.