Genome-wide association studies and Mendelian randomization analyses provide insights into the causes of early-onset colorectal cancer.

BACKGROUND: The incidence of early-onset colorectal cancer (EOCRC; diagnosed <50 years of age) is rising globally; however, the causes underlying this trend are largely unknown. CRC has strong genetic and environmental determinants, yet common genetic variants and causal modifiable risk factors underlying EOCRC are unknown. We conducted the first EOCRC-specific genome-wide association study (GWAS) and Mendelian randomization (MR) analyses to explore germline genetic and causal modifiable risk factors associated with EOCRC. PATIENTS AND METHODS: We conducted a GWAS meta-analysis of 6176 EOCRC cases and 65 829 controls from the Genetics and Epidemiology of Colorectal Cancer Consortium (GECCO), the Colorectal Transdisciplinary Study (CORECT), the Colon Cancer Family Registry (CCFR), and the UK Biobank. We then used the EOCRC GWAS to investigate 28 modifiable risk factors using two-sample MR. RESULTS: We found two novel risk loci for EOCRC at 1p34.1 and 4p15.33, which were not previously associated with CRC risk. We identified a deleterious coding variant (rs36053993, G396D) at polyposis-associated DNA repair gene MUTYH (odds ratio 1.80, 95% confidence interval 1.47-2.22) but show that most of the common genetic susceptibility was from noncoding signals enriched in epigenetic markers present in gastrointestinal tract cells. We identified new EOCRC-susceptibility genes, and in addition to pathways such as transforming growth factor (TGF) ß, suppressor of Mothers Against Decapentaplegic (SMAD), bone morphogenetic protein (BMP) and phosphatidylinositol kinase (PI3K) signaling, our study highlights a role for insulin signaling and immune/infection-related pathways in EOCRC. In our MR analyses, we found novel evidence of probable causal associations for higher levels of body size and metabolic factors-such as body fat percentage, waist circumference, waist-to-hip ratio, basal metabolic rate, and fasting insulin-higher alcohol drinking, and lower education attainment with increased EOCRC risk. CONCLUSIONS: Our novel findings indicate inherited susceptibility to EOCRC and suggest modifiable lifestyle and metabolic targets that could also be used to risk-stratify individuals for personalized screening strategies or other interventions.

Photochemically Aided Arteriovenous Fistula Creation to Accelerate Fistula Maturation.

Rates of arteriovenous fistula maturation failure are still high, especially when suboptimal size veins are used. During successful maturation, the vein undergoes lumen dilatation and medial thickening, adapting to the increased hemodynamic forces. The vascular extracellular matrix plays an important role in regulating these adaptive changes and may be a target for promoting fistula maturation. In this study, we tested whether a device-enabled photochemical treatment of the vein prior to fistula creation facilitates maturation. Sheep cephalic veins were treated using a balloon catheter coated by a photoactivatable molecule (10-8-10 Dimer) and carrying an internal light fiber. As a result of the photochemical reaction, new covalent bonds were created during light activation among oxidizable amino acids of the vein wall matrix proteins. The treated vein lumen diameter and media area became significantly larger than the contralateral control fistula vein at 1 week (p = 0.035 and p = 0.034, respectively). There was also a higher percentage of proliferating smooth muscle cells in the treated veins than in the control veins (p = 0.029), without noticeable intimal hyperplasia. To prepare for the clinical testing of this treatment, we performed balloon over-dilatation of isolated human veins and found that veins can tolerate up to 66% overstretch without notable histological damage.

Creating a Natural Vascular Scaffold by Photochemical Treatment of the Extracellular Matrix for Vascular Applications.

The development of bioscaffolds for cardiovascular medical applications, such as peripheral artery disease (PAD), remains to be a challenge for tissue engineering. PAD is an increasingly common and serious cardiovascular illness characterized by progressive atherosclerotic stenosis, resulting in decreased blood perfusion to the lower extremities. Percutaneous transluminal angioplasty and stent placement are routinely performed on these patients with suboptimal outcomes. Natural Vascular Scaffolding (NVS) is a novel treatment in the development for PAD, which offers an alternative to stenting by building on the natural structural constituents in the extracellular matrix (ECM) of the blood vessel wall. During NVS treatment, blood vessels are exposed to a photoactivatable small molecule (10-8-10 Dimer) delivered locally to the vessel wall via an angioplasty balloon. When activated with 450 nm wavelength light, this therapy induces the formation of covalent protein-protein crosslinks of the ECM proteins by a photochemical mechanism, creating a natural scaffold. This therapy has the potential to reduce the need for stent placement by maintaining a larger diameter post-angioplasty and minimizing elastic recoil. Experiments were conducted to elucidate the mechanism of action of NVS, including the molecular mechanism of light activation and the impact of NVS on the ECM.

Prospective study of the relationship between coffee and tea with colorectal cancer risk: the PLCO Cancer Screening Trial.

BACKGROUND: Coffee and tea are commonly consumed and carry potential anticancer components that could reduce the risk of colorectal cancer; however, their relationships with colorectal cancer risk remain inconsistent. METHODS: A prospective analysis was carried out to examine the relationships of coffee and tea intake with colorectal cancer risk in 57,398 men and women in the intervention arm of the National Cancer Institute-Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial, a national screening study that limits differential detection biases. Coffee and tea intakes were assessed by food frequency questionnaire. RESULTS: Six hundred and eighty-one incident colorectal cancer cases were ascertained during a median follow-up of 11.4 years. Greater coffee intake was not associated with risk of colorectal cancer (relative risk (RR)=1.08, 95% confidence interval (CI)=0.79-1.48, Ptrend=0.23). Stratifying by cancer site (Pheterogeneity=0.48) or stage (Pheterogeneity=0.83) did not alter the relationship. Associations remained unchanged in subsets of participants for either caffeinated or decaffeinated coffee or when stratifying by several colorectal cancer risk factors. Similarly, greater tea intake was not associated with colorectal cancer risk overall (RR=0.77, 95% CI=0.55-1.09, Ptrend=0.17) or by cancer site (Pheterogeneity=0.14) or stage (Pheterogeneity=0.60). These associations were not modified by several colorectal cancer risk factors. CONCLUSION: The findings of this study do not provide evidence to suggest that drinking coffee or tea is beneficial in protecting against colorectal cancer.

Ronidazole pharmacokinetics in cats following delivery of a delayed-release guar gum formulation.

Ronidazole (RDZ) is the only known effective treatment for feline diarrhea caused by Tritrichomonas foetus. This study aimed to develop guar gum-coated colon-targeted tablets of RDZ and to determine the pharmacokinetics of this delayed-release formulation in cats. Guar gum-coated tablets were administered orally once to five healthy cats (mean dose 32.3 mg/kg). The tablets were then administered once daily for 5 days to four cats (mean dose 34.5 mg/kg), and absorption studies repeated on day 5. Plasma was collected and analyzed for RDZ concentration, and pharmacokinetic noncompartmental and deconvolution analysis were performed on the data. There was negligible RDZ release until after 6 h, and a delayed peak plasma concentration (mean Cmax 28.9 µg/mL) at approximately 14.5 h, which coincides with colonic arrival in cats. Maximum input rate (mg/kg per hour) occurred between 6 and 16 h. This delayed release of ronidazole from guar gum-coated tablets indicates that release of RDZ may be delayed to deliver the medication to a targeted area of the intestine. Repeated dosing with guar gum tablets to steady-state did not inhibit drug bioavailability or alter the pharmacokinetics. Such targeted RDZ drug delivery may provide improved efficacy and reduce adverse effects in cats.

Aspirin but not ibuprofen use is associated with reduced risk of prostate cancer: a PLCO study.

BACKGROUND: Although most epidemiological studies suggest that non-steroidal anti-inflammatory drug use is inversely associated with prostate cancer risk, the magnitude and specificity of this association remain unclear. METHODS: We examined self-reported aspirin and ibuprofen use in relation to prostate cancer risk among 29 450 men ages 55-74 who were initially screened for prostate cancer from 1993 to 2001 in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. Men were followed from their first screening exam until 31 December 2009, during which 3575 cases of prostate cancer were identified. RESULTS: After adjusting for potential confounders, the hazard ratios (HRs) of prostate cancer associated with <1 and ≥ 1 pill of aspirin daily were 0.98 (95% confidence interval (CI), 0.90-1.07) and 0.92 (95% CI: 0.85-0.99), respectively, compared with never use (P for trend 0.04). The effect of taking at least one aspirin daily was more pronounced when restricting the analyses to men older than age 65 or men who had a history of cardiovascular-related diseases or arthritis (HR (95% CI); 0.87 (0.78-0.97), 0.89 (0.80-0.99), and 0.88 (0.78-1.00), respectively). The data did not support an association between ibuprofen use and prostate cancer risk. CONCLUSION: Daily aspirin use, but not ibuprofen use, was associated with lower risk of prostate cancer risk.

Leukemia-related chromosomal loss detected in hematopoietic progenitor cells of benzene-exposed workers.

Benzene exposure causes acute myeloid leukemia and hematotoxicity, shown as suppression of mature blood and myeloid progenitor cell numbers. As the leukemia-related aneuploidies monosomy 7 and trisomy 8 previously had been detected in the mature peripheral blood cells of exposed workers, we hypothesized that benzene could cause leukemia through the induction of these aneuploidies in hematopoietic stem and progenitor cells. We measured loss and gain of chromosomes 7 and 8 by fluorescence in situ hybridization in interphase colony-forming unit-granulocyte-macrophage (CFU-GM) cells cultured from otherwise healthy benzene-exposed (n=28) and unexposed (n=14) workers. CFU-GM monosomy 7 and 8 levels (but not trisomy) were significantly increased in subjects exposed to benzene overall, compared with levels in the control subjects (P=0.0055 and P=0.0034, respectively). Levels of monosomy 7 and 8 were significantly increased in subjects exposed to <10 p.p.m. (20%, P=0.0419 and 28%, P=0.0056, respectively) and ≥ 10 p.p.m. (48%, P=0.0045 and 32%, 0.0354) benzene, compared with controls, and significant exposure-response trends were detected (P(trend)=0.0033 and 0.0057). These data show that monosomies 7 and 8 are produced in a dose-dependent manner in the blood progenitor cells of workers exposed to benzene, and may be mechanistically relevant biomarkers of early effect for benzene and other leukemogens.

Meat consumption and the risk of incident distal colon and rectal adenoma.

BACKGROUND: Most studies of meat and colorectal adenoma have investigated prevalent events from a single screening, thus limiting our understanding of the role of meat and meat-related exposures in early colorectal carcinogenesis. METHODS: Among participants in the screening arm of the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial who underwent baseline and follow-up sigmoidoscopy (n=17,072), we identified 1008 individuals with incident distal colorectal adenoma. We calculated odds ratios (ORs) and 95% confidence intervals (95% CIs) for associations between meat and meat-related components and incident distal colorectal adenoma using multivariate logistic regression. RESULTS: We observed suggestive positive associations for red meat, processed meat, haeme iron, and nitrate/nitrite with distal colorectal adenoma. Grilled meat (OR=1.56, 95% CI=1.04-2.36), well or very well-done meat (OR=1.59, 95% CI=1.05-2.43), 2-amino-1-methyl-6-phenyl-imidazo[4,5-b]pyridine (PhIP) (OR=1.75, 95% CI=1.17-2.64), benzo[a]pyrene (OR=1.53, 95% CI=1.06-2.20), and total mutagenic activity (OR=1.57, 95% CI=1.03-2.40) were positively associated with rectal adenoma. Total iron (diet and supplements) (OR=0.69, 95% CI=0.56-0.86) and iron from supplements (OR=0.65, 95% CI=0.44-0.97) were inversely associated with any distal colorectal adenoma. CONCLUSION: Our findings indicate that several meat-related components may be most relevant to early neoplasia in the rectum. In contrast, total iron and iron from supplements were inversely associated with any distal colorectal adenoma.

Comprehensive analysis of hormone and genetic variation in 36 genes related to steroid hormone metabolism in pre- and postmenopausal women from the breast and prostate cancer cohort consortium (BPC3).

CONTEXT: Sex steroids play a central role in breast cancer development. OBJECTIVE: This study aimed to relate polymorphic variants in 36 candidate genes in the sex steroid pathway to serum concentrations of sex steroid hormones and SHBG. DESIGN: Data on 700 genetic polymorphisms were combined with existing hormone assays and data on breast cancer incidence, within the European Prospective Investigation into Cancer and Nutrition (EPIC) and the Nurses' Health Study (NHS) cohorts; significant findings were reanalyzed in the Multiethnic Cohort (MEC). SETTING AND PARTICIPANTS: We analyzed data from a pooled sample of 3852 pre- and postmenopausal Caucasian women from EPIC and NHS and 454 postmenopausal women from MEC. MAIN OUTCOME MEASURES: Outcome measures were SHBG, testosterone, dehydroepiandrosterone (DHEAS), androstenedione, estrone (E1), and estradiol (E2) as well as breast cancer risk. RESULTS: Globally significant associations were found among pre- and postmenopausal women combined between levels of SHBG and the SHBG gene and between DHEAS and the FSHR and AKR1C3 genes. Among postmenopausal women, serum E1 and E2 were significantly associated with the genes CYP19 and FSHR, and E1 was associated with ESR1. None of the variants related to serum hormone levels showed any significant association with breast cancer risk. CONCLUSIONS: We confirmed associations between serum levels of SHBG and the SHBG gene and of E1 and E2 and the CYP19 and ESR1 genes. Novel associations were observed between FSHR and DHEAS, E1, and E2 and between AKR1C3 and DHEAS.

Height and risk of prostate cancer in the prostate, lung, colorectal, and ovarian cancer screening trial.

BACKGROUND: The relationship between prostate cancer and height is uncertain. METHODS: We prospectively examined the association of height with prostate cancer among 34,268 men in the prostate, lung, colorectal, and ovarian cancer trial. Anthropometry was assessed at baseline and 2144 incident prostate cancer cases were identified upto 8.9 years of follow-up. RESULTS: Overall, tallness was not associated with the risk of prostate cancer or with the risk of non-aggressive disease, but the risk for aggressive prostate cancer tended to be greater in taller men (Gleason score > or = 7 or stage > or = III; P trend=0.05; relative risk (RR) for 190 cm + vs < or = 170 cm = 1.39, 95% confidence interval (95% CI): 0.96-2.01). This association was largely limited to men below the age of 65 years (P trend=0.008; RR for 190 cm + vs < or = 170 cm = 1.76, 95% CI: 1.06-2.93; P for interaction=0.009), although the number of cases was small and risk estimates were somewhat unstable. CONCLUSION: The results of this large prospective prostate cancer screening trial suggest that tallness is associated with increased risk for younger onset aggressive prostate cancer.

Human herpesvirus 8 seroprevalence among prostate cancer case patients and control subjects.

To investigate a possible association between human herpesvirus 8 (HHV-8) and prostate cancer, we evaluated HHV-8 seroprevalence in 2 case-control studies. HHV-8 antibodies were detected by immunofluorescence with cells expressing lytic viral proteins and by enzyme immunoassays with recombinant viral structural protein (K8.1) and latent protein (latency-associated nuclear antigen-1; open reading frame 73), respectively. HHV-8 seroprevalence tended to be lower in patients with prostate cancer than in control subjects, but there was no significant difference in either study. These data imply that HHV-8 is not a major prevalent cause of prostate cancer.

Evidence of a healthy volunteer effect in the prostate, lung, colorectal, and ovarian cancer screening trial.

Volunteers for prevention or screening trials are generally healthier and have lower mortality than the general population. The Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO) is an ongoing, multicenter, randomized trial that randomized 155,000 men and women aged 55-74 years to a screening or control arm between 1993 and 2001. The authors compared demographics, mortality rates, and cancer incidence and survival rates of PLCO subjects during the early phase of the trial with those of the US population. Incidence and mortality from PLCO cancers (prostate, lung, colorectal, and ovarian) were excluded because they are the subject of the ongoing trial. Standardized mortality ratios for all-cause mortality were 46 for men, 38 for women, and 43 overall (100 = standard). Cause-specific standardized mortality ratios were 56 for cancer, 37 for cardiovascular disease, and 34 for both respiratory and digestive diseases. Standardized mortality ratios for all-cause mortality increased with time on study from 31 at year 1 to 48 at year 7. Adjusting the PLCO population to a standardized demographic distribution would increase the standardized mortality ratio only modestly to 54 for women and 55 for men. Standardized incidence ratios for all cancer were 84 in women and 73 in men, with a large range of standardized incidence ratios observed for specific cancers.

Variation of long-lived free radicals responsible for the EPR native signal in bone of aged or diseased human females and ovariectomized adult rats.

The purpose of this study was to gain insights into the variations seen in the electron paramagnetic resonance (EPR) spectroscopy of the native signals of teeth and bones used for retrospective dosimetry measurements. We determined that changes occur in the long-lived free radicals responsible for the native signal of cortical bone in aging or diseased human females and aged ovariectomized rats. This was done by measuring the magnitude of the broad (BC) and narrow (NC) components of the native EPR signal of bone following chemical extraction, aging, crushing and thermal annealing. Bone from the upper midshaft of femora of young (17-34 years old, n=5) and elderly (70-92 years old, n=18) females was examined. The results showed that the elderly women had significantly higher BC than the younger women (P<0.01). A similar interpretation was made of the data from an aging female rat osteoporosis model. The results for the NC signals were similar. Finally, dramatic decreases in both NC and BC signals were seen in HIV positive and uncontrolled diabetic (one each) patients indicating the need for studying this signal for a broad spectrum of metabolic disorders. Experiments were performed which strongly indicate that iron liganded with organic molecules is the source of the BC signal. Finally, the accuracy achieved in this study indicates that resolving the dosimetric signal (g=2.0018) should be improved by subtraction of the deconvoluted NC and BC signals from the original spectrum.

Risk behaviours and benign prostatic hyperplasia.

OBJECTIVE: To identify risk factors for benign prostatic hyperplasia (BPH). SUBJECTS AND METHODS: Medical history data, including reported urological conditions and treatments, and risk factor data were collected from 34 694 participants in the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial, a randomized controlled trial designed to evaluate methods for the early detection of cancer. RESULTS: Asian men had the lowest risks (odds ratio, 95% confidence interval) for nocturia (0.7, 0.5-0.9), physician-diagnosed BPH (0.3, 0.2-0.5) and transurethral prostatectomy (TURP, 0.2, 0.1-0.6), while risks for Whites and Blacks were similar for most measures of BPH. Greater alcohol intake was associated with decreased nocturia (P trend = 0.002), BPH (P trend < 0.001) and TURP (P trend < 0.001). Current tobacco use was associated with decreased nocturia (0.8, 0.7-0.9), BPH (0.7, 0.6-0.8) and TURP (0.6, 0.4-0.8) but dose-response patterns were weak. CONCLUSION: Asian-Americans have the lowest risk of clinical BPH. Alcohol and possibly cigarettes are related to a lower risk for BPH.

[No convincing evidence for a causal relationship between childhood nasopharyngeal radium irradiation and head-neck tumors or hormone-related disorders later in life; a retrospective cohort study]. / Geen overtuigend bewijs voor een causaal verband tussen nasofaryngeale radiumbestraling op de kinderleeftijd en latere hoofd-halstumoren en hormonale aandoeningen; een historisch cohortonderzoek.

OBJECTIVE: To study the risk of malignant and benign tumours and hormone-related disorders among patients treated with nasopharyngeal radium irradiation for hypertrophic adenoid or hearing loss caused by otitis media serosa. DESIGN: Retrospective cohort study. METHOD: The medical record registries of 9 hospitals were used to identify a radium-exposed group (n = 5358) and a control group of unexposed patients (n = 5265), who were treated by an otolaryngologist in the period 1945-1981. The vital status of the subjects was determined using municipal resident registries, and the cause of death of decedents was retrieved from Statistics Netherlands (1950-1997). The data was also coupled with the Netherlands Cancer Registry (1989-1996). For the subjects still alive in 1997, the prevalence of relevant disorders was determined using a self-administered questionnaire and disorders reported by the participants were medically verified. The risk of disease in the radium group was then compared with that of the control group. RESULTS: The average radiation doses were 2.75, 0.109 and 0.015 Gy for nasopharynx, pituitary, and thyroid, respectively. There was no statistically significantly elevated risk for malignancies of the head and neck area (radium-exposed group; n = 14; control group: n = 11 (relative risk (RR): 1.2; 95% CI: 0.6-2.8)). Four of the five thyroid carcinomas were found in the radium-exposed group (RR: 3.8; 0.5-76). Elevated risks were observed for breast cancer (RR: 1.6; 0.9-2.7) and non-Hodgkin's lymphoma (RR: 2.7; 1.0-8.7). There was an increased risk for skin basal cell carcinoma (BCC) of the head and neck (odds ratio (OR): 2.6; 1.0-6.7), but the risk of BCC of other body parts was lower (OR: 0.3; 0.1-1.3). There were no major differences between radium and control subjects with respect to benign head and neck tumours (OR: 1.0; 0.5-1.7) or hormonal disorders. Exposed men reported slightly more fertility disorders than men in the control group (OR: 1.4; 1.0-2.1), but there was no clear dose-response relationship. CONCLUSION: After a mean follow-up of 31 years, there was no strong evidence for an elevated risk of head and neck tumours or hormone-related disorders in adulthood among subjects who had been treated with nasopharyngeal radium irradiation during childhood.

Serum lycopene, other serum carotenoids, and risk of prostate cancer in US Blacks and Whites.

Epidemiologic studies investigating the relation between individual carotenoids and risk of prostate cancer have produced inconsistent results. To further explore these associations and to search for reasons prostate cancer incidence is over 50% higher in US Blacks than Whites, the authors analyzed the serum levels of individual carotenoids in 209 cases and 228 controls in a US multicenter, population-based case-control study (1986-1989) that included comparable numbers of Black men and White men aged 40-79 years. Lycopene was inversely associated with prostate cancer risk (comparing highest with lowest quartiles, odds ratio (OR) = 0.65, 95% confidence interval (CI): 0.36, 1.15; test for trend, p = 0.09), particularly for aggressive disease (comparing extreme quartiles, OR = 0.37, 95% CI: 0.15, 0.94; test for trend, p = 0.04). Other carotenoids were positively associated with risk. For all carotenoids, patterns were similar for Blacks and Whites. However, in both the controls and the Third National Health and Nutrition Examination Survey, serum lycopene concentrations were significantly lower in Blacks than in Whites, raising the possibility that differences in lycopene exposure may contribute to the racial disparity in incidence. In conclusion, the results, though not statistically significant, suggest that serum lycopene is inversely related to prostate cancer risk in US Blacks and Whites.

Relationship of demographic and clinical factors to free and total prostate-specific antigen.

OBJECTIVES: To characterize the role of demographic and clinical parameters in the measurements of prostate-specific antigen (PSA), free PSA (fPSA), and percent free PSA (%fPSA). METHODS: This was a cohort study of volunteers to a randomized screening trial. A central laboratory determined PSA and fPSA for the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial. A baseline evaluation of free and total PSA was done for 7183 white, black, Asian, Hispanic, and other male volunteers, aged 55 to 74 years. Comparisons were made across racial and ethnic groups and across a set of clinical parameters from a baseline questionnaire. RESULTS: The median levels of serum PSA were less than 2.1 ng/mL in each age-race grouping of the study participants. The levels of free and total PSA were higher in black (n = 868, 12%) participants than in white (n = 4995, 70%) and Asian (n = 849, 11.8%) participants. Individuals who identified themselves as ethnically Hispanic (n = 339, 4.7%) had median PSA levels higher than whites who were not Hispanic. The free and total PSA levels increased with age, particularly among men 70 to 74 years old. However, the %fPSA levels showed less variation among the four racial groups or by age. The free and total PSA levels were higher among those who had a history of benign prostatic disease. CONCLUSIONS: Demographic (age and race/ethnicity) and clinical (history of benign prostatic disease) variables had a moderate effect on the measures of PSA and fPSA and very little effect on %fPSA.

Family cancer history and susceptibility to oral carcinoma in Puerto Rico.

BACKGROUND: Use of alcohol and tobacco are the major risk factors for cancers of the oral cavity and pharynx in most of the world. A heritable component to oral carcinoma risk also has been suggested, although only limited data are available on familial aggregation of this disease. METHODS: A population-based case-control study of 342 subjects with carcinomas of the oral cavity and pharynx (oral carcinoma) and 521 controls was conducted in Puerto Rico. The relation between family history of carcinomas of the oral cavity, the upper aerodigestive tract (UADT), and other selected sites with risk of oral carcinoma was explored using logistic regression modeling techniques. RESULTS: Risk of oral carcinoma was elevated for subjects reporting a first-degree relative with carcinoma of the oral cavity (odds ratio [OR], 2.5; 95% confidence interval [CI], 0.8-8.0) or any UADT carcinoma (OR, 2.6; 95% CI, 1.4-4.8). The increased risk associated with family history of UADT carcinoma tended to be greatest for subjects with known risk factors (i.e., heavy consumption of alcohol and/or tobacco and infrequent intake of raw fruits and vegetables) and with oral carcinoma diagnoses at ages younger than 65 years. CONCLUSIONS: These findings are consistent with a heritable component to oral carcinoma, although shared lifestyle risk factors may be partially involved.