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C Key

Publications and source records attributed to C Key.

At least 19 recordsLinked to original sources
PubMed2001

Trends in survival of patients with hepatocellular carcinoma between 1977 and 1996 in the United States.

The recent increase in the incidence of hepatocellular cancer in the United States is thought to underlie the rising mortality of this malignancy. However, it remains unknown whether survival of patients with hepatocellular carcinoma (HCC) has changed during the same time period. Using the SEER database (Surveillance, Epidemiology, and End Results) of the National Cancer Institute, we examined the temporal changes and determinants of survival among patients with histologically proven HCC over a 20-year period. Between 1977 and 1996, 7,389 patients diagnosed with HCC were followed in the survival database of SEER. The overall 1-year relative survival rate increased from 14% (95% confidence intervals (CI): 12-16) during 1977-1981 to 23% (95% CI: 21-24) during 1992 to 1996. Between the same two time periods, less improvement was seen in the 5-year survival rates, which increased from 2% (95% CI: 1-3) to only 5% (95% CI: 4-7). The median survival increased slightly from 0.57 years during 1977 to 1981 to 0.64 years during 1992 to 1996. In general, there were no significant differences in survival between men and women or between ethnic groups. During 1987 to 1991, a small fraction (0.8%) of patients underwent radical surgery; these patients had 1-year survival of 59% (95% CI: 35-83%), and 5-year survival of 35% (95% CI: 12-58%). Similar rates were seen during 1992-1996. In conclusion, a small improvement in survival of patients with HCC was seen between 1977 and 1996. Most of this apparent benefit is restricted to the first year following cancer diagnosis, raising the possibility of lead-time bias. There were no significant differences related to gender or ethnicity.

Adult↗
PubMed2000

Primary mediastinal malignancies in children: report of 22 patients and comparison to 197 adults.

PURPOSE: Examine a contemporary series of patients with primary pediatric malignant mediastinal tumors and determine epidemiology, histology, treatment, and survival. Patients and Methods. All malignancies diagnosed between January 1, 1973 and December 31, 1995 were analyzed. RESULTS: Twenty-two patients, age 18 years or less, with pediatric primary mediastinal malignancies were identified from a database of 110,284 patients with primary malignancies. During the same period, 197 adult patients with primary mediastinal malignancies were identified. Fifty-nine percent of the pediatric patients were male. Median age was 11 years. Lymphoma was present in 55%, neurogenic malignancies in 23%, malignant germ cell tumors in 18%, and sarcoma in 5%. Neurogenic tumors presented in infants and lymphomas and germ cell tumors presented in teens (p = 0.005). In treated children, surgery was used more often in neurogenic tumors and germ cell tumors than in lymphomas (p = 0.002). Five-year survival was 74% for lymphomas, 67% for neurogenic tumors, 25% for germ cell tumors, and 61% overall (p = 0.23). Compared to adults, children had more neurogenic tumors (p < 0.001) and fewer thymomas (p = 0.0499). There were no significant differences in staging or survival between children and adults. CONCLUSIONS: Pediatric mediastinal malignancies occurred with a frequency of 1/5,013 patients with malignant tumors. Lymphoma, neurogenic tumors, and germ cell tumors predominated. Compared to adults, children had more neurogenic tumors and fewer thymomas. Within the pediatric group, differences were found in age of presentation between histologic groups. These differences between adults and children, and between infants and teens, should be considered when evaluating a patient suspected of having mediastinal malignancy.

Adolescent↗
PubMed2000

Patient and tumor characteristics of colon cancers with microsatellite instability: a population-based study.

Molecular screening for microsatellite instability (MSI) in colon cancers has been proposed to identify individuals with hereditary nonpolyposis colorectal cancer. To date, most reports of MSI in colorectal cancer have been based on studies of clinical case series or high-risk families. We examined the proportion of incident colon cancers in the general population that exhibit MSI by patient and tumor characteristics. We interviewed 201 colon cancer cases ascertained by the New Mexico Tumor Registry in the metropolitan Albuquerque area for demographic information, lifestyle factors, medical history, and family cancer history. Paired normal and tumor tissue specimens were obtained for each case. Three microsatellite markers were used; instability was defined as observed alteration at two or more loci. Overall, 37 of 201 (18%) colon cancers exhibited instability. MSI was more common among cases >70 years (26%) and most common among cases >80 years (38%). MSI was significantly associated with tumors in the proximal colon and with later stage and poor differentiation among cases >70 years. MSI was not associated with a history of polyps. Family history of colorectal cancer was associated with MSI only among cases <50 years. When all factors were analyzed jointly in a regression model, proximal subsite and poor differentiation remained significantly associated with MSI. One patient, whose tumor exhibited MSI, fulfilled the Amsterdam Criteria for hereditary nonpolyposis colorectal cancer. Our study provides a population-based estimate of MSI in colon tumors and a representative estimate of the proportion of colorectal cancer patients in the general population who consent to be interviewed for family cancer history and to have biological samples analyzed.

Adult↗
PubMed1999

Sex differences in energy expenditure in non-human primates.

Female mammals bear the energetic costs of gestation and lactation. Therefore, it is often assumed that the overall energetic costs are greater for females than they are for males. However, the energetic costs to males of intrasex competition may also be considerable, particularly if males maintain a much larger body size than females. Using data from 19 non-human primates, this paper examines the relationship between male and female energetic costs both in the short term (daily energy expenditure) and the long term (the energetic cost of producing a single offspring). It is shown that the major determinant of sex differences in energetic costs is body size dimorphism. In the long term, the energetic costs are often greater for females, but, when male body size exceeds female body size by 60% or more, male energetic costs are greater than those for females. That is, in highly sexually dimorphic species the energetic costs of gestation and lactation for the females are matched by the energetic costs to the males of maintaining a large body size.

Animals↗
PubMed1999

Morphological and taxonomic affinities of the Olduvai ulna (OH 36).

The OH 36 ulna derives from Upper Bed II in the Olduvai Gorge, and is dated to circa 1.1-1.2 Myr. Multivariate analyses incorporating data from samples of modern humans, common and pygmy chimpanzees, gorillas, orangutans, and two other early hominin ulnae, Omo L40-19 and KNM-BK 66, suggest that OH 36 belonged to an individual with powerful forearms consistent with a locomotor repertoire that included arboreal locomotion. However, there is no compelling evidence that it made regular use of its forelimbs as supports when travelling on the ground. When compared with levels of intra- and intertaxon size and shape variation in the comparative sample (humans, chimpanzees, gorillas), the differences between OH 36, KNM-BK 66, and Omo L40-19 are compatible with OH 36 differing from the other two fossil hominin ulnae to the extent that modern humans differ from modern great apes. KNM-BK 66 and Omo L40-19 differ from each other in overall size and shape only to the degree that would be expected within any of the individual modern comparative samples. Based on these analyses, there is no evidence to support the hypothesis that OH 36 and Omo L40-19 belong to the same species of fossil hominin, or to two species that shared a similar forelimb locomotor repertoire. We suggest that OH 36 has the greater claim to be assigned to Paranthropus boisei, and we recommend that for the time being the latter be referred to the tribe Hominini gen. et sp. indet. The surprising result of these analyses is the overall size and shape similarity between Omo L40-19 and KNM-BK 66, two fossils that are separated in time by more than 1.5 million years, and which have traditionally been assumed to represent hominin species with quite different locomotor patterns.

Animals↗
PubMed1999

The relationship between diet and breast cancer in men (United States).

OBJECTIVES: The purpose of this paper was to investigate the relationship between food and beverage consumption and the development of breast cancer in men. METHODS: Possible relationships of dietary factors to risk of breast cancer in men were assessed in a case-control study conducted between 1983 and 1986. Cases (N = 220) were ascertained from ten population-based cancer registries. Controls (N = 291) were selected by random-digit dialing (< age 65) and from Health Care Financing Administration Medicare beneficiary lists (> or = age 65). RESULTS: No trends in risk were observed with increasing intakes of specific foods, except for an increase in risk with citrus fruits. No increase in risk with increasing amounts of specific fats, vitamins, or minerals or with amounts of protein, fiber, carbohydrate, starches, nitrites, or alcohol consumed was observed, except for an increase in risk with dietary vitamin C consumption. A decreasing trend in risk with dietary niacin and with coffee and an increasing trend in risk with tea consumption were observed. No associations were found with use of any dietary supplements, including vitamin C. CONCLUSIONS: The observed associations are not consistent with findings from studies of breast cancer in women and probably do not represent causal relationships. Dietary factors are unlikely to be strong determinants of breast cancer in men.

Adult↗
PubMed1999

Primary mediastinal malignancies: findings in 219 patients.

The purpose of this study was to determine the demographics, histology, methods of treatment, and survival in primary mediastinal malignancies. We did a retrospective review of the statewide New Mexico Tumor Registry for all malignant tumors treated between January 1, 1973 and December 31, 1995. Benign tumors and cysts of the mediastinum were excluded. Two hundred nineteen patients were identified from a total of 110,284 patients with primary malignancies: 55% of tumors were lymphomas, 16% malignant germ cell tumors, 14% malignant thymomas, 5% sarcomas, 3% malignant neurogenic tumors, and 7% other tumors. There were significant differences in gender between histologies (P < 0.001). Ninety-four percent of germ cell tumors occurred in males, 66% of neurogenic tumors were in females; other tumors occurred in males in 58% of cases. There were also significant differences in ages by histology (P < 0.001). Neurogenic tumors were most common in the first decade, lymphomas and germ cell tumors in the second to fourth decades, and lymphomas and thymomas in patients in their fifth decades and beyond. Stage at presentation (P = 0.001) and treatment (P < 0.001) also differed significantly between histologic groups. Five-year survival was 54% for lymphomas, 51% for malignant germ cell tumors, 49% for malignant thymomas, 33% for sarcomas, 56% for neurogenic tumors, and 51% overall. These survival rates were not statistically different (P > 0.50). Lymphomas, malignant germ cell tumors, and thymomas were the most frequently encountered malignant primary mediastinal neoplasms in this contemporary series of patients. Demographics, stage at presentation, and treatment modality varied significantly by histology. Despite these differences, overall five-year survival was not statistically different.

Adult↗
PubMed1998

Localized well-differentiated thyroid carcinoma: survival analysis of prognostic factors and (131)I therapy.

BACKGROUND: Recommendations regarding therapeutic use of (131)I for patients with well-differentiated thyroid cancer remain controversial. Between 1969 and 1993, 1171 patients with papillary (including mixed) or follicular thyroid cancer were reported to the New Mexico Tumor Registry. Of these, 1075 cases (77.6% female, median age 41 years) were available for analysis of survival plots and previously recognized risk factors. Extent of operation was documented for 344 patients. METHODS: One hundred twenty-seven (37%) patients underwent postoperative (131)I ablation. Median follow-up was 99 months. A proportional hazards model was constructed using age, gender, stage, histology, and use of radioiodine. The same variables plus extent of operation were examined in the smaller group. RESULTS: Kaplan-Meier survival estimates at 12 years were 96.2% for patients younger than 45 years and 68.6% for those older than 45 years. Age, gender, and histology, but not stage, were important survival variables (P <.05). Adjusting for other risk factors, there was no apparent survival benefit associated with radioiodine following clinically appropriate thyroidectomy. Findings from the small group mirrored those of the large group. CONCLUSIONS: (131)I may not be as efficacious as previously believed for patients with well-differentiated thyroid cancer confined to the neck.

Adenocarcinoma, Follicular↗
PubMed1998

A technique for establishing the identity of 'isolated' fossil hominin limb bones.

Associated skeletons, which are specimens preserving more than one body part from the same individual, are especially important for taxonomic and functional analyses. This study concentrates on the subset of associated skeletons which preserve the reciprocal surfaces of a joint. It uses laser scanning to explore whether the shapes of the reciprocal surfaces of a joint of an individual are significantly more congruent than the surfaces of randomly-matched pairings taken from the same species. Laser scanning was used to capture the distal articular surface of the left tibia of OH35 and the trochlear articular surface of the talus of OH8, both from Bed I, Olduvai Gorge, Tanzania. The degree of congruency between those articular surfaces was tested against the congruency of the talocrural joint of AL 288-1 (Australopithecus afarensis), and the congruency of both associated and randomly-matched talocrural joints of modern humans, chimpanzees and gorillas. The results suggest that OH35 and OH8 do not come from the same individual and may not come from the same species. Although this analysis leaves open the taxonomic affinity of OH35, it demonstrates the potential of laser scanning for capturing 3D data in palaeoanthropology. It also demonstrates the potential for using the relative congruency of reciprocal joint surfaces as a test of the likelihood that isolated limb bones are components of a single individual.

Animals↗
PubMed1996

Alaska Native cancer update: incidence rates 1989-1993.

Five-year average annual age-adjusted cancer incidence rates for Alaska Natives (Eskimos, Indians, and Aleuts) for the most recent period (1989-1993) are compared to rates of 20 years earlier. Rates for all cancers combined increased 28 and 25% in men and women, respectively, during the 25-year interval. Increases were seen in men in cancers of the lung, prostate, and colon and in women for cancers of the lung, breast, and corpus uteri. Rates are also compared to data from the the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) program for United States whites. Rates for all cancers combined in Alaska Native women are now similar to those of United States whites, whereas rates in Alaska Native men are lower than the United States, but only 10% lower. Significant site-specific differences previously reported between Alaska Natives and United States whites persist.

Alaska↗
PubMed1991

Incidence of hairy cell leukemia, mycosis fungoides, and chronic lymphocytic leukemia in first known HTLV-II-endemic population.

Unlike human T cell leukemia-lymphoma virus type I (HTLV-I), HTLV-II has not been convincingly linked to a malignancy. In the first 10 months of serologic screening for HTLV-I/II among blood donors in New Mexico in 1988-1989, HTLV-I/II infection was found in 27 donors. HTLV-I/II infection was present in 1.0%-1.6% of American Indian and 0.16%-0.27% of Hispanic donors compared with 0.009%-0.06% of non-Hispanic white donors. HTLV-II was identified by DNA amplification in 12 of 13 samples from Indian and Hispanic seropositive donors. Despite apparent endemic HTLV-II infection in these populations, New Mexico Tumor Registry data showed that the incidences of hairy cell leukemia, mycosis fungoides, and chronic lymphocytic leukemia were comparable among the three ethnic groups. A population with endemic HTLV-II infection has been identified, and there is no evidence of increased risk for these three malignancies in the endemic groups.

Blood Donors↗
PubMed1988

Thrombosis and infarction of the left atrial appendage in an infant: a case report.

A case of thrombosed and infarcted left atrial appendage is presented. These findings occurred in a 28-day-old infant who died of pneumonia due to Hemophilus influenzae. Congenital abnormalities of the atrial appendages including hypoplasia, right and left isomerism and juxtapositions, and aneurysmal dilatations with and without pericardial defects are relatively uncommon. Acquired defects are also uncommon, and are often iatrogenic in nature. This report describes the case of a thrombosed and infarcted left atrial appendage in a 28-day-old infant.

Coronary Disease↗
PubMed1987

Changing cigarette habits and bladder cancer risk: a case-control study.

With the use of data from the 8,764 subjects in the National Bladder Cancer Study, the separate contribution of various aspects of a person's cigarette smoking history to his increased risk of bladder cancer was estimated. These estimates have not been previously available, owing to the smaller sizes of earlier studies. Our data indicated that people who have only smoked unfiltered cigarettes have higher risks than those who have only smoked filtered cigarettes but that people who have switched from unfiltered to filtered have experienced no reduction in risk. Our data also indicated that smoking cessation substantially reduced the risk. The former smoker appeared to benefit both because he stopped adding to the burden of irreversible damage and because he ceased being exposed to some reversible hazard. Thus the former smoker had a lower risk than the current smoker even though they had smoked the same number of cigarettes daily for the same number of years, but the former smoker's risk remained higher than the risk of a person who never smoked. Our data suggest that one-half of the bladder cancer occurring among men in the United States and one-third of that among women is caused by cigarette smoking.

Adult↗
PubMed1986

Choice of cancer therapy varies with age of patient.

We used data on 22,899 cancer cases collected by the New Mexico Tumor Registry to examine the relationship between patient age and the use of potentially curative therapy for cancers of selected sites and acute leukemias. For cancers of most sites, either local or regional stage, the proportion of cases receiving potentially curative therapy declined with age. For local-stage cancers, the proportion not given any treatment increased with age. Overall mortality rates during the first year after diagnosis were much higher for local-stage cases without treatment than for those who received treatment. These data show that cancer therapy varies with age and suggest that decision making regarding therapy is influenced by the presence of other diseases.

Adult↗
PubMed1984

A review of 1,147 cases of Sheets lens implantations.

A review of 1,147 Sheets Style 30 intraocular lens implantations is presented. The incidence of complications is similar to or less than that of J-loop lenses. In-the-bag placement appears to eliminate some of the problems associated with J-loop lenses placed in the ciliary sulcus.

Humans↗
PubMedDate not supplied

A Prisoner's Dilemma model of the evolution of paternal care.

The heavy energetic demands of gestation, lactation and rearing of offspring mean that studies of paternal care in primates usually focus on female reproductive effort. Here it is shown that both male and female reproductive effort must be considered in order to understand how paternal care evolved. This is done using the Prisoner's Dilemma, best known as a model of reciprocal altruism. It is found that the relative cost of reproduction for males and females is crucially important in determining co-operative and competitive strategies. In particular, when male reproductive costs are less than female reproductive costs, males co-operate with females even when females do not reciprocate. This surprising behaviour, termed non-reciprocal altruism, is comparable with male investment in a female and her offspring.

Altruism↗