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1.
Health Educ Res ; 30(3): 371-9, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25801103

ABSTRACT

The incidence of melanoma is rising among Hispanic populations in the United States. The purpose of this study is to evaluate the impact of a pilot sun safety educational intervention conducted from 2006 to 2012 on Hispanic early adolescents in a high ultraviolet environment. Nineteen schools with high Hispanic enrollment were recruited from urban neighborhoods in Los Angeles. The analytic sample was restricted to students identifying as Hispanic or Latino (n = 777). A mixed effects linear model was used to test mean changes from pre- to posttest on students' sun protection knowledge, attitudes and behaviors. Significant improvements were observed across several cognitive outcomes related to sun protection, including knowledge of and attitudes toward sun protection and self-efficacy to wear sunscreen. However, changes in sun protective behaviors were not achieved. Although some improvements were observed, future studies should identify the factors that motivate sun protection in this population and develop tailored prevention strategies, as improving the sun safe behaviors of Hispanic youths may aid in reducing the risk of melanoma in adulthood in this population.


Subject(s)
Health Education , Hispanic or Latino , Schools , Sunburn/prevention & control , Sunscreening Agents/administration & dosage , Adolescent , Adolescent Behavior , Female , Health Knowledge, Attitudes, Practice , Humans , Los Angeles/epidemiology , Male , Melanoma/prevention & control , Pilot Projects , Risk Reduction Behavior , Self Efficacy , Sunburn/epidemiology , Surveys and Questionnaires , United States
2.
J Natl Cancer Inst ; 84(10): 764-71, 1992 May 20.
Article in English | MEDLINE | ID: mdl-1573662

ABSTRACT

BACKGROUND: A cohort mortality study among 5886 chemical manufacturing workers was completed in 1987 and showed increased mortality due to pancreatic cancer. PURPOSE: We conducted a nested case-control study of pancreatic cancer among these chemical manufacturing workers to identify risk factors for this disease. METHODS: Twenty-eight verified cases of pancreatic cancer and 112 matched controls were studied. Next of kin of each subject were interviewed to determine lifestyle factors, including tobacco, alcohol, and coffee consumption. Written work records and interviews with co-workers were used to determine chemical exposures at the plant under study. RESULTS: DDT was associated with pancreatic cancer (risk ratio [RR] for ever exposed compared with never exposed = 4.8; 95% confidence interval = 1.3-17.6). Among subjects who had a mean exposure to DDT of 47 months, the risk was 7.4 times that among subjects with no exposure. Two DDT derivatives, Ethylan and DDD, were additionally associated with pancreatic cancer (RR = 5.0 and 4.3, respectively); exposures to these two chemicals were correlated, and it was not possible to determine whether each acted independently of the other. Smoking was identified as an independent risk factor, but controlling for smoking (and other potential confounders) in the analyses did not appreciably alter the risks seen for DDT, DDD, or Ethylan. CONCLUSIONS: Exposure to DDT was associated with pancreatic cancer. The association was not explained by exposure to lifestyle factors or other chemicals, and risk increased with both duration of exposure and latency since first exposure. IMPLICATIONS: These results may indicate that DDT can cause pancreatic cancer in humans under circumstances of heavy and prolonged exposure.


Subject(s)
Chemical Industry , DDT/adverse effects , Occupational Diseases/chemically induced , Pancreatic Neoplasms/chemically induced , Case-Control Studies , Cause of Death , DDT/analogs & derivatives , Humans , Life Style , Male , Multivariate Analysis , Occupational Diseases/mortality , Pancreatic Neoplasms/mortality , Risk Factors
3.
Diabetes ; 42(12): 1786-90, 1993 Dec.
Article in English | MEDLINE | ID: mdl-8243824

ABSTRACT

Associations between infant-feeding patterns and risk of IDDM were investigated in a nationwide Finnish case-control study of 690 IDDM children < 15 yr of age. Each child was matched by date of birth and sex to a randomly selected population-based control child. Univariate analysis revealed that the risk of IDDM was increased by approximately 1.5 in children for whom breast-feeding was terminated at < 2 mo of age, doubled in those who were exclusively breast-fed for < 2 mo, and doubled in those who were introduced to dairy products at < 2 mo of age. In further multivariate analyses of these factors, it was found that introduction of dairy products at an early age was the most important risk factor, and the observed univariate effects of duration of breast-feeding variables were explained by their correlation with this factor. This is the first observational study to show that early introduction of dairy products is independently associated with an increased risk of IDDM. Adjustment for mother's education and age, child's birth order, or birth weight did not affect the results.


Subject(s)
Dairy Products , Diabetes Mellitus, Type 1/epidemiology , Infant Food , Adolescent , Age Factors , Analysis of Variance , Breast Feeding , Child , Child, Preschool , Diabetes Mellitus, Type 1/etiology , Female , Finland/epidemiology , Humans , Infant , Male
4.
Biostatistics ; 2(1): 63-84, 2001 Mar.
Article in English | MEDLINE | ID: mdl-12933557

ABSTRACT

Methods for the analysis of unmatched case-control data based on a finite population sampling model are developed. Under this model, and the prospective logistic model for disease probabilities, a likelihood for case-control data that accommodates very general sampling of controls is derived. This likelihood has the form of a weighted conditional logistic likelihood. The flexibility of the methods is illustrated by providing a number of control sampling designs and a general scheme for their analyses. These include frequency matching, counter-matching, case-base, randomized recruitment, and quota sampling. A study of risk factors for childhood asthma illustrates an application of the counter-matching design. Some asymptotic efficiency results are presented and computational methods discussed. Further, it is shown that a 'marginal' likelihood provides a link to unconditional logistic methods. The methods are examined in a simulation study that compares frequency and counter-matching using conditional and unconditional logistic analyses and indicate that the conditional logistic likelihood has superior efficiency. Extensions that accommodate sampling of cases and multistage designs are presented. Finally, we compare the analysis methods presented here to other approaches, compare counter-matching and two-stage designs, and suggest areas for further research.To whom correspondence should be addressed.

5.
Bone Marrow Transplant ; 50(9): 1173-9, 2015 Sep.
Article in English | MEDLINE | ID: mdl-25961775

ABSTRACT

We previously showed that minimal residual disease (MRD) detection pre-hematopoietic cell transplant (HCT) and acute GvHD (aGvHD) independently predicted risk of relapse in pediatric ALL. In this study we further define risk by assessing timing of relapse and the effects of leukemia risk category and post-HCT MRD. By multivariate analysis, pre-HCT MRD <0.1% and aGvHD by day +55 were associated with decreased relapse and improved event-free survival (EFS). Intermediate leukemia risk status predicted decreased relapse, and improved EFS and overall survival (OS). Patients with pre-HCT MRD ⩾0.1% who did not develop aGvHD compared with those with MRD <0.1% who did develop aGvHD had much worse survival (2 years EFS 18% vs 71%; P=0.001, 2 years OS 46 vs 74%; P=0.04). Patients with pre-HCT MRD <0.1% who did not experience aGvHD had higher rates of relapse than those who did develop aGvHD (40% vs 13%; P= 0.008). Post-HCT MRD led to a substantial increase in relapse risk (HR=4.5, P<0.01). Patients at high risk of relapse can be defined after transplant using leukemia risk category, presence of MRD pre or post HCT, and occurrence of aGvHD. An optimal window to initiate intervention to prevent relapse occurs between day +55 and +200 after HCT.


Subject(s)
Hematopoietic Stem Cell Transplantation , Precursor Cell Lymphoblastic Leukemia-Lymphoma , Acute Disease , Adolescent , Adult , Allografts , Child , Child, Preschool , Disease-Free Survival , Female , Graft vs Host Disease/blood , Graft vs Host Disease/diagnosis , Graft vs Host Disease/mortality , Humans , Infant , Male , Neoplasm, Residual , Precursor Cell Lymphoblastic Leukemia-Lymphoma/blood , Precursor Cell Lymphoblastic Leukemia-Lymphoma/diagnosis , Precursor Cell Lymphoblastic Leukemia-Lymphoma/mortality , Precursor Cell Lymphoblastic Leukemia-Lymphoma/prevention & control , Recurrence , Survival Rate , Time Factors
6.
J Natl Cancer Inst Monogr ; (26): 39-42, 1999.
Article in English | MEDLINE | ID: mdl-10854484

ABSTRACT

We describe the advantages of using established cohort studies that have collected blood samples to investigate the role of genes in the etiology of cancer. These studies include the cost-efficiency and reliability of nested case-control substudies from the cohort for exploration of gene-disease associations and gene-environment interactions as well as gene penetrance. Also, the cohort may serve as a well-defined "mini-population" from which to study population stratification and molecular markers of ethnicity. We conclude that cohort studies can play a significant role in assessing the role of genetic markers for common tumors or multiple cancer sites.


Subject(s)
Neoplasms/genetics , Case-Control Studies , Cohort Studies , Cost-Benefit Analysis , Environment , Genetic Markers , Humans , Neoplasms/etiology
7.
Int J Radiat Oncol Biol Phys ; 23(3): 599-603, 1992.
Article in English | MEDLINE | ID: mdl-1612961

ABSTRACT

From 1988 to 1991, 21 patients with uveal melanoma were treated in a Phase I study with episcleral plaque radiotherapy (EPRT). This irradiation was combined with localized current field episcleral hyperthermia (LCFHT). Tumor stage was: T3 = 15 (71%) and T2 = 6 (29%). Follow-up ranged from 2 to 42 months (mean 9.2 months). EPRT was given using custom built I-125 gold plaques. Radiation doses to the tumor apex ranged from 13 to 123 Gy (mean dose 70.0 Gy) given at a mean dose rate of 55 cGy/hr. LCFHT was given with 500 KHz frequency for 45 min immediately before EPRT. The temperature was controlled on the scleral surface using four thermocouples. T mean ranged from 42.5 degrees C to 45 degrees C +/- 0.5 degrees C (mean 43.4 degrees C). The study patients showed rapid tumor necrosis. A 25% mean decrease of apical tumor dimension was noted, p = 0.0007. At least ambulatory vision (greater than 5/200) was maintained by 17/21 (81%) patients. Visual acuity was seen to improve greater than 6 months post-plaque therapy in 10 (48%) study patients. This was following an intermediate decrease in visual acuity. Severe complications, including large hemorrhagic retinal detachment and large vitreous hemorrhage, were seen in two (9.5%) of the early study patients. A mean scleral temperature reduction to less than or equal to 44 degrees C +/- 0.5 degrees C resulted in good treatment tolerance and a lack of serious complications in subsequently treated patients. A Phase II prospective randomized trial comparing LCFHT with 60 versus 80 Gy EPRT dose to the tumor apex is currently being activated for patients with choroidal melanoma.


Subject(s)
Choroid Neoplasms/therapy , Hyperthermia, Induced , Melanoma/therapy , Adolescent , Adult , Aged , Aged, 80 and over , Combined Modality Therapy , Female , Humans , Male , Middle Aged
8.
Int J Radiat Oncol Biol Phys ; 40(1): 139-47, 1998 Jan 01.
Article in English | MEDLINE | ID: mdl-9422570

ABSTRACT

PURPOSE: Adenocarcinoma of the prostate is the most common human cancer of internal organs. Radical surgery is regarded by many to be the treatment of choice for capsule confined disease. Since accurate preoperative assessment of tumor stage is difficult to define, many patients are subsequently found to have pathological stage C (T3) disease. These patients should be considered for adjuvant radiotherapy. METHODS AND MATERIALS: A group of 201 PS C (T3) unselected patients, treated with radical prostatectomy and limited pelvic lymphadenectomy, received postoperative irradiation to the prostate bed. This radiotherapy was given between 42-90 days after surgery and consisted of a median dose of 48 Gy. Patient survival, disease free survival, time to clinical and chemical relapse and the incidence of local and systemic relapse were analyzed. The influence of multiple parameters on the treatment outcome including patient age, treatment period, clinical stage, pathological stage, Gleason's score, prostate specific antigen (PSA), radiotherapy techniques and radiation dose were examined using univariate and multivariate analysis. Follow-up ranged from 3 to 15 years, with a median of 5 years. RESULTS: The overall 5- and 10-year actuarial survival was 92% and 83% (median > 10 years), respectively and the 5- and 10-year disease-free survival (clinical and PSA) was 67% and 53% (median > 10 years), respectively. A total of 61 (30%) patients had a recurrence, including 23 (11%) patients who had clinical and 38 (19%) who had PSA recurrence. Of the 23 patients with clinical recurrence, 10 (5%) had local recurrence, including two patients who had local and systemic recurrence. Pathological stage and Gleason's score were independently predictive of recurrence (each with p < 0.001 after controlling for the other). Patients in the worst prognostic category with pathological stage C3 and Gleason's score 8-10 were predicted to be at 7.2 times the risk of recurrence, compared to stage C1 or C2 and Gleason's score 2-7 patients. Preoperative PSA level (> 25 ng/ml) was also an important independent factor predicting tumor recurrence, p = 0.05. All other investigated parameters were not significant in predicting tumor recurrence. This treatment program was very well tolerated by the study patients, with seven (3.5%) recorded with major and 18 (9%) with minor surgical complications, while 65% of patients had minor and clinically insignificant radiation complications. CONCLUSION: Surgery followed by moderate dose radiotherapy in patients with PS C (T3) prostatic carcinoma was well tolerated and resulted in excellent overall and disease free survival, with a low incidence of local recurrence. New treatment strategies need to be developed for patients with C3 tumors and those with high (8-10) Gleason's score and those with high (> 25 ng/ml) PSA level at diagnosis.


Subject(s)
Prostatectomy , Prostatic Neoplasms/radiotherapy , Prostatic Neoplasms/surgery , Aged , Disease-Free Survival , Humans , Male , Middle Aged , Neoplasm Staging , Prostate-Specific Antigen/blood , Prostatectomy/adverse effects , Prostatic Neoplasms/blood , Prostatic Neoplasms/mortality , Prostatic Neoplasms/pathology , Radiotherapy Dosage , Radiotherapy, Adjuvant/adverse effects , Urinary Incontinence/etiology
9.
Int J Radiat Oncol Biol Phys ; 21(4): 949-54, 1991 Sep.
Article in English | MEDLINE | ID: mdl-1917624

ABSTRACT

From 1973 to 1986, 160 patients with adenocarcinoma localized to the prostate were treated with radical prostatectomy and pelvic lymphadenectomy. In 78 (49%) patients more advanced stage of disease was found at surgery and they received local pelvic irradiation (RT). This consisted of 45 Gy for microscopic and 55 Gy for macroscopic residual disease. RT was given at 1.8 Gy a day, using the four-field "box" technique with the 23 MV X ray beam. Pelvic lymph node metastases were found in 28 (36%) patients who, in addition to RT, received systemic therapy: 20 with cyclophosphamide alone, 4 combined with 5-Fluorouracil, and 4 patients received DES. The 5- and 10-year overall actuarial survival was 95 and 77%, respectively, and the 5- and 10-year disease-free survival was 58 and 43%, respectively. Recurrent tumor was found in 34 (44%) patients. Of these 34 patients, 32 (94%) had distant metastatic tumor and 2 (6%) had local recurrence in the pelvis. The presence of metastatic disease in pelvic lymph nodes had clinical significance since it influenced disease-free survival and the incidence of tumor recurrence. The 10-year disease-free survival for the 50 patients with no lymph node metastases was 51%, as compared to 28% for the 28 patients with such metastases, p = 0.001. Similarly, recurrent tumor was found in 28% of the former and 68% of the latter patients, p = 0.002. Other important parameters predicting recurrence were: clinical stage, p = 0.018, histological grade, p = 0.013, and Gleason's grade, p = 0.002. This treatment program was very well tolerated and of low toxicity. There was no surgical mortality. Surgical complications were seen in 10 (13%) patients including: minor in 5 and major in 5. At 1 year, 77% of the patients remained continent, while 10% had mild stress incontinence. Of the remaining 13% only 3 (4%) patients had severe incontinence (greater than 5 pads daily). RT toxicity was mild with 38% experiencing diarrhea. Severe toxicity was seen in 2 (3%) patients who, early in the study, developed scrotal and lower extremity edema. Severe chemotherapy complications were seen in 1 (4%) patient who had severe neutropenic sepsis. Postoperative radiotherapy is a well tolerated, safe and effective treatment in patients who have microscopic or macroscopic residual tumor following radical prostatectomy.


Subject(s)
Adenocarcinoma/radiotherapy , Prostatectomy , Prostatic Neoplasms/radiotherapy , Adenocarcinoma/epidemiology , Adenocarcinoma/surgery , Combined Modality Therapy , Follow-Up Studies , Humans , Male , Prostatic Neoplasms/epidemiology , Prostatic Neoplasms/surgery , Retrospective Studies , Survival Rate
10.
Int J Radiat Oncol Biol Phys ; 24(2): 247-51, 1992.
Article in English | MEDLINE | ID: mdl-1526863

ABSTRACT

During an 8-year period, 85 patients with uveal melanomas were treated with episcleral plaque radiotherapy (EPRT). The T-stage was: T1-3 (4%), T2-29 (34%) and T3-53 (62%). The mean tumor elevation was 6.1 mm. Radiation dose was prescribed at the tumor apex and at D5mm. The mean D5mm dose was 150.1 Gy (range 70.5-430 Gy) and the mean dose at the apex was 102.6 Gy (range 29.8-200 Gy). Useful vision (greater than 5/200) was maintained in 73% of patients. The 5-year actuarial survival was 88%. Metastatic disease developed in 9 (11%) patients, 6 of whom died of their disease. Basal tumor dimensions were important factors predicting metastatic disease, p = 0.002. A decrease in tumor evaluation was seen in 82%. There was a much lower incidence of decrease in tumor radial and circumferential dimensions, 47.5 and 46%, respectively, p less than 0.001. Treatment complications were common (56%), particularly in patients with large tumors (72%), p = 0.04. The incidence of complications was higher in patients treated prior to 1988 as compared to those who were treated more recently (67 vs 35%, p = 0.010). There were 13 (15%) patients who had enucleation. This included 12 treated before 1986 and 1 patient treated subsequently (46 vs 2%, p less than 0.001). In a univariate analysis, tumor height and radiation dose at D5mm were important factors predicting enucleation, p = 0.004. In a multivariate analysis, however, the most important factor predicting enucleation was treatment administration prior to 1986, p less than 0.001). A sharp decrease in the incidence of severe complications, including enucleation, as seen after 1985, is likely due to a major effort in treatment optimization.


Subject(s)
Brachytherapy/instrumentation , Choroid Neoplasms/radiotherapy , Melanoma/radiotherapy , Adult , Aged , Aged, 80 and over , Brachytherapy/adverse effects , Choroid Neoplasms/epidemiology , Eye Enucleation , Female , Humans , Male , Melanoma/epidemiology , Middle Aged , Multivariate Analysis , Retrospective Studies , Survival Rate
11.
Int J Radiat Oncol Biol Phys ; 16(3): 601-7, 1989 Mar.
Article in English | MEDLINE | ID: mdl-2646259

ABSTRACT

A Phase I study using deep regional hyperthermia (HT) with an annular phased array was conducted in 14 U.S. medical centers from 1980 through 1986. There were 353 patients whose average age was 57 years. All patients had advanced recurrent or persistent tumors. Prior frequently complex, multimodality anti-cancer therapy was received by 71% of the patients. Gastrointestinal adenocarcinoma was present in 146 (41%) patients, genitourinary tumors in 86 (24%), soft tissue sarcomas in 46 (13%), malignant melanoma in 21 (6%) and 15% had other tumors. The sites treated included: pelvis 55%, abdomen 21%, liver 14%, thorax 6%, and other sites 3%. All patients received deep regional HT with an average frequency of 55 MHz. A total of 1412 HT treatments was administered to these 353 patients with an aim to increase the temperature in the volume of interest to greater than 42 degrees C for greater than or equal to 30 minutes. Thermal dose (TD in equivalent minutes at 42.5 degrees C) was less than 50 in 104 (29%), greater than or equal to 50 less than 100 in 30 (11%), greater than or equal to 100 in 26 (7%), and greater than 200 in 34 (10%). The remaining 150 (42%) patients had TD = 0. In addition to HT, 260 (74%) received radiotherapy (RT). RT was given at 180 or 200 cGy daily with an average total dose of 33.4 Gy. A total of 42 (12%) patients were given chemotherapy (CT) with HT, and 15 (4%) CT + HT + RT/HT alone was given to 47 (13%) patients. Complete response (CR) was obtained in 35 (10%) and partial response (PR) in 59 (17%) patients. CR was 12% in patients who received RT, vs 2% in those who did not receive it, p = 0.003. Radiation dose was an important factor influencing response, p less than 0.001. Thermal dose was not an important parameter influencing tumor response. A duration of CR ranged from 4 to 73 weeks with an average duration of 31 weeks and the median duration of 28 weeks. The overall 2-year survival was 13% with the median survival of 42 weeks. Patients with CR and PR had a 2 year survival of 41%, and a median survival of 71 weeks. This compared with 8% 2-year survival and 24 weeks median survival in patients who did not have CR or PR, p less than 0.001. Of the patients presenting with significant pain, 62% had complete or partial pain relief.(ABSTRACT TRUNCATED AT 400 WORDS)


Subject(s)
Hyperthermia, Induced , Neoplasms/therapy , Adolescent , Adult , Aged , Aged, 80 and over , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Combined Modality Therapy , Female , Humans , Male , Middle Aged , Multicenter Studies as Topic , Neoplasms/drug therapy , Neoplasms/radiotherapy , Prognosis
12.
Int J Radiat Oncol Biol Phys ; 21(3): 715-21, 1991 Aug.
Article in English | MEDLINE | ID: mdl-1651307

ABSTRACT

A total of 41 stereotactic interstitial brain implants in 39 patients were performed for recurrence after teletherapy (recurrence implant), or as part of initial treatment in conjunction with teletherapy (primary implant). Implanted tumors consisted of malignant gliomas (33), other primary brain tumors (3), and single metastatic lesions (3). All patients were temporarily implanted with Ir-192 using a coaxial catheter afterloading system; two patients were implanted twice. Survival post-implant for glioblastoma multiforme (GBM), 13 patients, was 10 months whether implanted primarily or for recurrence. Mean time to recurrence, measured from initiation of teletherapy to implantation, was 10 months. Twenty patients with anaplastic astrocytoma (AA) had a median survival post-implant of 23 months for primary implants (7 patients) and 11 months for recurrence implants (13 patients). Mean time to recurrence, measured from initiation of teletherapy to implantation, was 19 months. Three patients (9%) of the evaluable group required reoperation for symptomatic mass effect, all with initial diagnosis of AA. Survival for this subgroup was 14, 22, and 32 months post-implantation. Using stereotactic techniques, interstitial brachytherapy of brain tumors was technically feasible with negligible acute morbidity and mortality, and appeared to offer limited prolongation of control for a subset of patients with recurrent malignant gliomas. The role of this modality in primary treatment for malignant gliomas needs to be further defined by prospectively randomized trials.


Subject(s)
Astrocytoma/radiotherapy , Brachytherapy , Brain Neoplasms/radiotherapy , Glioblastoma/radiotherapy , Adolescent , Adult , Aged , Astrocytoma/epidemiology , Astrocytoma/secondary , Brain Neoplasms/epidemiology , Brain Neoplasms/secondary , Glioblastoma/epidemiology , Glioblastoma/secondary , Humans , Iridium Radioisotopes/therapeutic use , Middle Aged , Neoplasm Recurrence, Local/epidemiology , Neoplasm Recurrence, Local/radiotherapy , Retrospective Studies , Survival Analysis
13.
Environ Health Perspect ; 102 Suppl 8: 47-51, 1994 Nov.
Article in English | MEDLINE | ID: mdl-7851330

ABSTRACT

A stratified version of nested case-control sampling which we call "countermatching" is presented. This design uses data available for all cohort members to obtain a sample for collecting additional information in a case-control substudy. Hitherto the only stratified sampling design for such studies has involved matching of controls to cases with respect to confounding variables. However, in some situations, rather than sampling to make controls as similar as possible to cases, we might wish to make them as different as possible. This is achieved by the counter-matched design. Statistical analysis of counter-matched studies is straightforward using existing computer software. We investigate the use of the design when a surrogate measure of exposure is available for the full cohort, but accurate exposure data is to be collected only in a nested case-control study, and when exposure data are available for the whole cohort but data concerning important confounders are not. Asymptotic relative efficiency calculations indicate that a substantial efficiency gain relative to simple random sampling of controls can be expected in these situations. We also illustrate how the design might be implemented in practice.


Subject(s)
Case-Control Studies , Sampling Studies , Bias , Breast Neoplasms/epidemiology , Breast Neoplasms/prevention & control , Cohort Studies , Confounding Factors, Epidemiologic , Contraceptives, Oral/therapeutic use , Female , Humans , Incidence , Likelihood Functions , Lung Neoplasms/epidemiology , Mass Screening/statistics & numerical data , Mining , Models, Statistical , Occupational Exposure/statistics & numerical data , Pancreatic Neoplasms/epidemiology , Radon/adverse effects , Research Design , Risk Factors , Sample Size , Smoking/epidemiology , Software , Uranium/adverse effects
14.
Environ Health Perspect ; 87: 27-35, 1990 Jul.
Article in English | MEDLINE | ID: mdl-2269231

ABSTRACT

It has recently been shown that the relative risks of the order of 2 to 4 that are frequently found for cancer among relatives of affected cases are unlikely to be explainable by shared environmental risk factors. Classical methods of epidemiological analysis are not well suited to such analysis because they assume that the outcomes of each individual are independent. Classical methods of genetic analysis, on the other hand, are limited in their handling of environmental factors and variable ages of onset. The recent development of random effects models for survival analysis, however, appears to bridge this gap. Specifically, a proportional hazards model is postulated for the effects of measured covariates and of one or more components of frailty that are unmeasured but assumed to have some common distribution and known covariance structure within each family. From these assumptions, the posterior expectation of the hazard for each individual can be derived, given the covariate value and the observed and expected disease history of the family. These are then treated as known in a standard partial likelihood analysis; this is essentially a form of expectation-maximization algorithm. However, this does not provide a valid estimate of the covariance matrix because it fails to take account of the variability in the estimates of the frailties; an alternative approach using the imputation-posterior algorithm is suggested. This paper describes extensions of this approach to multivariate frailty distributions, modifications for application to pedigree and case-control studies, some simulation results, and applications to studies of breast cancer in twins and of lung cancer in relation to family smoking habits.


Subject(s)
Neoplasms/mortality , Proportional Hazards Models , Survival Analysis , Adenocarcinoma/epidemiology , Algorithms , Breast Neoplasms/epidemiology , Breast Neoplasms/genetics , Case-Control Studies , Cohort Studies , Computer Simulation , Diseases in Twins , Female , Humans , Los Angeles/epidemiology , Lung Neoplasms/epidemiology , Male , Multivariate Analysis , Neoplasms/genetics , Pedigree , Smoking , Sweden/epidemiology
15.
J Thorac Cardiovasc Surg ; 98(4): 614-7, 1989 Oct.
Article in English | MEDLINE | ID: mdl-2796368

ABSTRACT

Between 1963 and 1986, 195 patients with carcinoma of the esophagus were seen in the Department of Radiation Oncology at the University of Southern California School of Medicine. Of these 195 patients, 137 had unresectable or inoperable tumors and received radiotherapy. A combination of radiotherapy and surgical therapy was used in 46 patients, 9 patients were treated with surgery alone, and three with chemotherapy alone. Among the nonsurgical patients, 13 scored less than 50 on the Karnofsky scale, 25 had distant metastases, and 69 lost more than 10% of their body weight. The majority (94%) had squamous cell carcinoma and a few (6%) had adenocarcinoma. Fifty percent had middle esophageal lesions, 30% had lower lesions, and 20% had upper esophageal lesions. Stage I was diagnosed in 13%, II in 27%, III in 29%, and IV in 27%; the disease was not staged in 5%. The 5-year actuarial survival rate for all patients was 4% (median 32 weeks). The 5-year survival rate of the 46 patients with combination therapy was 18%, and it was 2% for the remaining 149 patients (p less than 0.001). These figures are independent of stage of disease. The 2-year survival rate by stage was as follows: I, 25%; II, 21%; III, 5%; and IV, 0% (p less than 0.001). Complete response was obtained in 18% and partial response in 41%. Complete response was dependent on the tumor stage. It was 40% for stage I disease, 23% for stage II, 11% for stage III, and 6% for stage IV disease. Similarly, a larger percentage (39%) of the 46 patients with combination surgical/radiation therapy had a complete response than of patients treated by either radiotherapy alone (n = 137, 12%) or surgery alone (n = 9, 11%). Complete response and initial performance status were important factors influencing survival (p less than 0.001). Surgery with adjuvant irradiation offered a better survival rate than radiotherapy or surgery used as single modalities. Treatment results for patients with advanced carcinoma of the esophagus remain poor.


Subject(s)
Esophageal Neoplasms/surgery , Adult , Aged , Aged, 80 and over , Combined Modality Therapy , Esophageal Neoplasms/mortality , Esophageal Neoplasms/pathology , Esophageal Neoplasms/radiotherapy , Female , Humans , Male , Middle Aged , Postoperative Complications , Radiotherapy/adverse effects , Survival Rate
16.
J Thorac Cardiovasc Surg ; 96(2): 237-41, 1988 Aug.
Article in English | MEDLINE | ID: mdl-3398546

ABSTRACT

During a 10-year period, 46 patients with unresectable or inoperable carcinoma of the esophagus were treated with teletherapy-brachytherapy combination at the University of Southern California School of Medicine. Stage distribution was as follows: stage I, 5 (11%) patients; stage II, 23 (50%) patients; stage III, six (13%) patients; and stage IV, 12 (26%) patients. Thirteen patients were treated for recurrent disease, including 11 patients initially treated with teletherapy and two who had had surgical resection. Radiotherapy was given by teletherapy in 33 and brachytherapy in all 46 patients. An average tumor dose was 50 Gy with teletherapy and 20 Gy per application with brachytherapy. There were 25 patients who had more than one brachytherapy application. The 5-year actuarial survival rate for 28 patients with stage I or II disease was 12%, with a median of 13 months. This compared with no 5-year survivals and a median survival of 10 months for the 18 patients with stage III or IV disease. Failure at the primary site was seen in 16 (35%) patients. Complete response was seen in 20%, partial response in 76%, and no response in 4%. Treatment was well tolerated. Complications included esophageal stenosis in two patients and tracheoesophageal fistula in one. Teletherapy-brachytherapy combination is an effective treatment in the management of unresectable or inoperable carcinoma of the esophagus.


Subject(s)
Brachytherapy , Carcinoma, Squamous Cell/radiotherapy , Esophageal Neoplasms/radiotherapy , Adenocarcinoma/mortality , Adenocarcinoma/pathology , Adenocarcinoma/radiotherapy , Adult , Aged , Aged, 80 and over , Brachytherapy/adverse effects , Carcinoma, Squamous Cell/mortality , Carcinoma, Squamous Cell/pathology , Esophageal Neoplasms/mortality , Esophageal Neoplasms/pathology , Female , Humans , Male , Middle Aged , Radiation Injuries/etiology
17.
Recent Results Cancer Res ; 107: 244-8, 1988.
Article in English | MEDLINE | ID: mdl-3375558

ABSTRACT

Between 1981 and 1985, 44 patients with advanced metastatic carcinoma of the liver were treated with deep microwave hyperthermia (HT) in five medical centers in the US. This HT was given with a BSD-1000 Annular Phased Array (BSD Medical Corporation, Salt Lake City, Utah). Of the 44 patients treated, 18 (41%) were in poor general condition and scored less than 60 on the Karnofsky scale. In 50% upper abdominal pain was a major presenting symptom. Prior chemotherapy (CT) had been given in 12 (27%) patients, while 10 (23%) had received prior radiotherapy (RT). Colon (73%) was the most frequent site of the primary tumor, and adenocarcinoma (79%) was the most frequent histological diagnosis. A total of 150 HT treatments were given, with an average of 3.4. HT alone was administered to 12 (27%), HT-RT to 15 (34%), HT-CT to 13 (30%) and HT-RT-CT to four (9%). Therapeutic temperature was reached in 28 (64%) patients. The majority (66%) tolerated treatment well. Due to the poor general condition of over one-third of the patients, prior therapy in 50% and the presence of advanced tumor in all, it is not surprising to see a response rate of only 36%. The response rate was 53% among patients receiving RT in addition to HT and 46% in patients who had therapeutic temperature. Survival ranged from less than 1 to 63 months, with an average of 11 months. Relief of pain was observed in 8 of 22 patients who presented with this symptom. HT can be safely delivered to patients with metastatic tumor to the liver.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Hyperthermia, Induced , Liver Neoplasms/secondary , Adenocarcinoma/secondary , Adenocarcinoma/therapy , Adult , Aged , Combined Modality Therapy , Evaluation Studies as Topic , Female , Humans , Liver Neoplasms/therapy , Male , Microwaves , Middle Aged
18.
Recent Results Cancer Res ; 107: 136-40, 1988.
Article in English | MEDLINE | ID: mdl-2453899

ABSTRACT

During a 2-year period 31 sites in 27 patients with recurrent, previously treated tumors received a combination of interstitial 192Ir radiation (RT) with microwave hyperthermia (HT). Head and neck sites were treated most frequently (48%), with breast and vagina each representing about 20% of sites. Complete response (CR) with no local recurrence was obtained in 61%, partial response (PR) in 11 (36%), and one (3%) had less than 50% tumor regression. Of these patients, nine had no evidence of tumor following HT-RT therapy, 8/18 in the CR group and 1/11 in the PR group. Significant factors influencing CR were: radiation dose, tumor volume and duration of tumor control following the initial therapy (p less than 0.02). Treated site, histology and thermal dose were not significant factors influencing tumor regression. Complications of significance developed in one patient who had local skin necrosis. Interstitial HT-RT combination provides an effective palliative therapy for recurrent and/or persistent tumors. Randomized trials are necessary to assess the effectiveness of this combination as a component part of primary management of selected tumors.


Subject(s)
Brachytherapy , Hyperthermia, Induced , Neoplasm Recurrence, Local/therapy , Palliative Care , Combined Modality Therapy , Evaluation Studies as Topic , Humans , Neoplasm Recurrence, Local/radiotherapy
19.
Am J Surg ; 154(4): 447-50, 1987 Oct.
Article in English | MEDLINE | ID: mdl-3661851

ABSTRACT

From 1956 to 1978, 646 patients were treated with radiotherapy for carcinoma of the nose (350 patients, 54 percent), eyelids (159 patients, 25 percent), pinna (93 patients, 14 percent), and skin adjacent to the lip (44 patients, 7 percent). The histologic distribution was 72 percent basal cell carcinoma, 18 percent squamous cell carcinoma, and 10 percent mixed basal and squamous cell features. Tumors less than 2 cm in diameter were found in 602 patients (93 percent), whereas 44 patients (7 percent) had larger tumors. Tumor involvement of cartilage and bone was seen in 23 patients at the time of diagnosis. The 5, 10, and 20 year control rates were 99 percent, 98 percent, and 98 percent, respectively, for 502 tumors less than 2 cm in diameter. This compared favorably with control rates of 92 percent at 5 years and 79 percent at 10 years for tumors from 2 to 5 cm in diameter and 60 percent at 5 years and 53 percent at 8 years for 12 patients with massive tumors (p less than 0.0001). The histologic characteristics of the lesion had a strong influence on tumor control (p less than 0.02). Of the patients with cartilage or bone invasion, tumor was controlled in 19 (83 percent). Of these 19 patients, 11 had no evidence of disease for 3 years or more. Of all 646 patients treated, failure was seen in 60 (9 percent). It correlated well with the size of the lesion, being 7 percent for tumors of less than 2 cm and 50 percent for tumors of greater than 5 cm. Of the 60 patients in whom treatment failed, 48 (80 percent) had prior definitive therapy. Radiotherapy was an efficient modality to control operative failures; however, it was not as efficient at control in patients in whom previous radiotherapy failed. Operation was the treatment of choice to salvage patients in whom radiotherapy failed. Of the patients in whom retreatment failed, 10 were known to have died from skin cancer, and an additional 6 patients were presumed to have died from the cancer. This study has demonstrated a good control rate and good cosmetic results for small tumors of the eyelids, pinna, and nose. In addition, a good control rate was obtained in patients with cartilage and bone involvement. Treatment of massive tumors should involve planned operative resection with adjuvant radiotherapy.


Subject(s)
Skin Neoplasms/radiotherapy , Adult , Aged , Aged, 80 and over , Carcinoma, Basal Cell/pathology , Carcinoma, Basal Cell/radiotherapy , Carcinoma, Basosquamous/pathology , Carcinoma, Basosquamous/radiotherapy , Carcinoma, Squamous Cell/pathology , Carcinoma, Squamous Cell/radiotherapy , Ear, External , Eyelids , Female , Humans , Male , Middle Aged , Neoplasm Recurrence, Local , Nose , Radiotherapy Dosage , Skin Neoplasms/pathology
20.
Am J Clin Oncol ; 14(1): 80-6, 1991 Feb.
Article in English | MEDLINE | ID: mdl-1702923

ABSTRACT

This is an analysis of treatment results over a 23-year period in 241 patients with carcinoma of the esophagus. The treatment for unresectable patients was external beam radiotherapy (EBRT) alone (mean dose 55 Gy) in 137 (57%) combined with brachytherapy (mean dose 50 + 40 Gy) in 46 (19%), and chemotherapy alone in 3 (1%) patients. In the 55 resectable patients, treatment was resection alone in 9 (4%), and combined with radiotherapy (mean dose 43 Gy) in 46 (19%) patients. The 1-, 2-, and 5-year survival for the 241 patients was 36, 15, and 5%, respectively (median 38 weeks). The 5-year survival was 18% for radiotherapy (RT)-surgery (S) patients, 11% for EBRT with brachytherapy, 2% for EBRT alone, and 0% for patients who had S alone, p less than 0.001. Survival correlated well with initial performance status, treatment, stage of disease, tumor size, radiation dose, and degree of response, p less than 0.001, but not with tumor location in the esophagus and patients' race and sex, p = 0.44. Serious complications occurred in 5 (2%) patients treated with RT alone and in 4 (7%) patients treated with S alone or combined with RT. The leading cause of death was persistent or recurrent tumor in the chest found in 39% patients.


Subject(s)
Carcinoma/radiotherapy , Esophageal Neoplasms/radiotherapy , Adult , Aged , Aged, 80 and over , Brachytherapy/adverse effects , Carcinoma/mortality , Carcinoma/pathology , Carcinoma/surgery , Combined Modality Therapy , Esophageal Neoplasms/mortality , Esophageal Neoplasms/pathology , Esophageal Neoplasms/surgery , Female , Humans , Male , Middle Aged , Palliative Care , Radiotherapy Dosage , Remission Induction , Survival Rate
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