Non-Hodgkin's lymphoma and other cancers among a cohort of patients with systemic lupus erythematosus

OBJECTIVE

To investigate whether systemic lupus erythematosus (SLE) is associated with non-Hodgkin's lymphoma or other malignant neoplasms.

METHODS

Data on a cohort of 1,585 patients with SLE from the nationwide Danish Hospital Discharge Register were linked to information in the Danish Cancer Registry to determine the occurrence of cancer during up to 15 years of followup. The expected number of cancers was calculated from accumulated person-years and national cancer incidence rates.

RESULTS

There was a significant excess of non-Hodgkin's lymphoma among the SLE patients, based on 8 cases observed against 1.5 expected (relative risk [RR] 5.2, 95% confidence interval 2.2-10.3). In addition, a significantly increased RR was found for cancer of the lung (RR 1.9; n = 15), the liver (RR 8.0; n = 5), and the vagina/vulva (RR 5.7; n = 3).

CONCLUSION

There seemed to be a positive association between SLE and non-Hodgkin's lymphoma. Other cancers with a possible virus-related etiology, such as liver and vaginal/vulva cancer, were also observed in excess. In addition, there was an indication of an increased risk of lung cancer among patients who were hospitalized for SLE.

Chromosome 13 poly(ADP-ribose) polymerase polymorphisms and lung cancer risk

A 193 base pair repeat polymorphism in the human poly(ADP-ribose) polymerase (PADPRP) pseudogene found on chromosome 13 has been associated with lung cancer, endemic Burkitt lymphoma, B-cell lymphoma, breast cancer and colorectal carcinoma. We investigated the frequency of the PADPRP genetic polymorphism in a hospital-based case-control study of lung cancer for 54 cases and 47 controls. There was a statistically significant difference in allelic frequency between Caucasians and African Americans (p<0.001). For African Americans, the odds ratio for lung cancer and the 'B' allele was 2.38 (95% C.I.=0.73, 7.69) and for Caucasians 0.44 (95% C.I.=0.11, 1.77). The results for the African Americans, however, were not in Hardy-Weinberg equilibrium, although the Caucasians were. Thus, this study, albeit small, does not find that the PADPRP pseudogene duplicated region located on chromosome 13 is a risk factor for lung cancer.

Cause-specific mortality in women receiving hormone replacement therapy

To assess the risks and benefits of menopausal hormone replacement therapy, we followed a 23,346-member, population-based cohort of Swedish women who were prescribed menopausal estrogens for an average of 8.6 years for mortality. Compared with the general population, the standardized mortality ratio for all-cause mortality in this cohort was 0.77 (95% confidence limits = 0.73, 0.81). Deaths in each of the 12 major categories of causes of death except for injuries occurred 12% to 86% less frequently than expected. We examined in detail four specific causes of death according to the type of hormone prescribed, namely weak estrogens (primarily estriol), more potent estrogens (primarily estradiol and conjugated estrogens) in combination with a progestin, and more potent estrogens without a progestin. Mortality from endometrial cancer was not related to the prescription of weak estrogens or an estrogen-progestin combination, but mortality was 40% higher in women prescribed more potent estrogens without a progestin. Women prescribed weak estrogens, more potent estrogens, and the combined estrogen-progestin regimen were at reduced risk of death from ischemic heart disease (standardized mortality ratios of 0.7, 0.6, and 0.4, respectively). The more potent estrogens and the estrogen-progestin combination were associated with a marked reduction in risk of intracerebral hemorrhage (standardize mortality ratios of 0.4 and 0.6, respectively) and "other" cerebrovascular disease, but not other types of stroke. The concern that use of progestins would lead to psychic disorders related to suicide received no support from our results. Breast cancer results are described elsewhere. These data provide little evidence of an adverse effect of the combined estrogen-progestin regimen as compared with estrogens alone on mortality. They do indicate, however, that both selection factors and biology may contribute to the almost across-the-board-reduction in mortality associated with hormone replacement therapy.

Epidemiologic determinants of seroreactivity to human papillomavirus (HPV) type 16 virus-like particles in cervical HPV-16 DNA-positive and-negative women

The epidemiologic determinants of seroreactivity to human papillomavirus (HPV) type 16 L1/L2 virus-like particles (VLPs) were assessed separately in HPV-16 DNA-positive and -negative women participating in a nested case-control study of incident cervical neoplasia. Seventy-four women with cervical HPV-16 DNA and 656 cytologically normal HPV-16 DNA-negative subjects were interviewed and tested at two time points for viral DNA and once (at the later time) for VLP seroreactivity. Among subjects who were currently HPV-16 DNA-negative, seroreactivity odds ratios increased from 2.9 for 2-5 male sex partners (vs. 0 or 1) to 5.4 for 6-9 partners and 14.0 for > or = 10. Thus, prior cervical infection may be a major determinant of seroreactivity in HPV-16 DNA-negative women. This trend was not observed in HPV-16 DNA-positive subjects. Seroreactivity was independently associated with oral contraceptive use, particularly in HPV-16 DNA-negative subjects with use for > or = 10 years. Consequently, a possible role for virus-steroid hormone interactions in seroconversion is suggested.

Breast cancer and hormonal contraceptives: further results. Collaborative Group on Hormonal Factors in Breast Cancer

The Collaborative Group on Hormonal Factors in Breast Cancer has brought together and reanalysed the worldwide epidemiological evidence on breast cancer risk and use of hormonal contraceptives. Original data from 54 studies, representing about 90% of the information available on the topic, were collected, checked and analysed centrally. The 54 studies were performed in 26 countries and include a total of 53,297 women with breast cancer and 100,239 women without breast cancer. The studies were varied in their design, setting and timing. Most information came from case-control studies with controls chosen from the general population; most women resided in Europe or North America and most cancers were diagnosed during the 1980s. Overall 41% of the women with breast cancer and 40% of the women without breast cancer had used oral contraceptives at some time; the median age at first use was 26 years, the median duration of use was 3 years, the median year of first use was 1968, the median time since first use was 16 years, and the median time since last use was 9 years. The main findings, summarised elsewhere, are that there is a small increase in the risk of having breast cancer diagnosed in current users of combined oral contraceptives and in women who had stopped use in the past 10 years but that there is no evidence of an increase in the risk more than 10 years after stopping use. In addition, the cancers diagnosed in women who had used oral contraceptives tended to be less advanced clinically than the cancers diagnosed in women who had not used them. Despite the large number of possibilities investigated, few factors appeared to modify the main findings either in recent or in past users. For recent users who began use before age 20 the relative risks are higher than for recent users who began at older ages. For women whose use of oral contraceptives ceased more than 10 years before there was some suggestion of a reduction in breast cancer risk in certain subgroups, with a deficit of tumors that had spread beyond the breast, especially among women who had used preparations containing the highest doses of oestrogen and progestogen. These findings are unexpected and need to be confirmed. Although these data represent most of the epidemiological evidence on the topic to date, there is still insufficient information to comment reliably about the effects of specific types of oestrogen or of progestogen. What evidence there is suggests, however, no major differences in the effects for specific types of oestrogen or of progestogen and that the pattern of risk associated with use of hormonal contraceptives containing progestogens alone may be similar to that observed for preparations containing both oestrogens and progestogens. On the basis of these results, there is little difference between women who have and have not used combined oral contraceptives in terms of the estimated cumulative number of breast cancers diagnosed during the period from starting use up to 20 years after stopping. The cancers diagnosed in women who have used oral contraceptives are, however, less advanced clinically than the cancers diagnosed in never users. Further research is needed to establish whether the associations described here are due to earlier diagnosis of breast cancer in women who have used oral contraceptives, to the biological effects of the hormonal contraceptives or to a combination of both. Little information is as yet available about the effects on breast cancer risk of oral contraceptive use that ceased more than 20 years before and as such data accumulate it will be necessary to re-examine the worldwide evidence.

Biological aspects of multiple myeloma

Although considerable progress has been made towards understanding many aspects of myeloma, the myeloma stem cell and the factors that drive the disease remain elusive. Recent developments in the molecular analysis of clonality have helped to confirm the presence of pre-switch B cells that are of the same clone as the myeloma plasma cells. The role of these cells in myelomagenesis has not been demonstrated, and the isotypic heterogeneity of the clonally-relevant cells suggests that the pre-switch B cells are pre-malignant progenitors of the tumour cells. Thus, the circulating clonal B cells appear to be the earliest progenitors of the mature, monoclonal plasma cells. IL-6, and possibly other cytokines, are involved in driving this process. The role of IL-6 in myeloma is complex and more involved than its proposed growth factor function. In the absence of IL-6, dependent cells become apoptotic. Increased IL-6 signalling also leads to apoptosis of myeloma cells, possibly as a result of terminal differentiation. In the presence of exogenous IL-6, the IL-6 receptor appears to be the rate-limiting factor in the pathway's activity. IL-6 may regulate the survival of myeloma cells by stimulating c-myc transcription, possibly from the P0 promoter. The high levels of c-myc transcripts and protein could regulate myeloma cell proliferation and apoptotic death by controlling p53 expression and, through it, the expression of the Rb and BAX genes. Proliferative signalling in myeloma cells is likely to be intrinsic, within the tumour cell compartment. Molecules such as CD28 and B7, both expressed by less mature myeloma cells, could represent one such self-self stimulatory mechanism, with IL-6, possibly through stimulation of c-myc expression, providing the signals for survival and differentiation.

Mammographic features and breast cancer risk: effects with time, age, and menopause status

BACKGROUND

Mammographic images from women with a high proportion of epithelial and stromal breast tissues are described as showing high-density parenchymal patterns. Most past studies that noted an increase in breast cancer risk associated with mammographic parenchymal patterns showing high density either 1) lacked information on other breast cancer risk factors, 2) were too small, or 3) included insufficient follow-up time to adequately resolve persisting doubts whether mammographic features are "independent" measures of breast cancer risk and not a detection artifact.

PURPOSE

The purpose of this study was twofold: 1) to evaluate the associations between mammographic features and other breast cancer risk factors and 2) to assess effects of mammographic features on breast cancer risk by time, age, and menopause status.

METHODS

To address these questions, we analyzed detailed information from a large, nested case-control study with 16 years of follow-up. This study used information from both screening and follow-up phases of the Breast Cancer Detection Demonstration Project, a nationwide program that offered annual breast cancer screening for more than 280,000 women from 1973 to 1980. Mammographic features were assessed from the base-line screening mammographic examination for 1880 incident case subjects and 2152 control subjects. Control subjects were randomly selected from women of the same age and race as each case subject. Control subjects attended the same screening center as the case subject and were free of breast cancer at the case subject's date of diagnosis. Odds ratios (ORs) with 95% confidence intervals (CIs) provided estimates of the relative risk of breast cancer.

RESULTS

Mammographic features were associated with known breast cancer risk factors. However, the high-density parenchymal pattern effects were independent of family history, age at first birth, alcohol consumption, and benign breast disease. The increase risk for women with Wolfe's two high-density parenchymal patterns, P2 (OR = 3.2; 95% CI = 2.5-4.0) and Dy (OR = 2.9; 95% CI = 2.2-3.9), was explained primarily by measured percent of the breast with dense mammographic appearance. Compared with women with no visible breast density, women who had a breast density of 75% or greater had an almost fivefold increased risk of breast cancer (95% CI = 3.6-7.1). These effects persisted for 10 or more years and were noted for both premenopausal and postmenopausal women of all ages.

CONCLUSIONS

Of the breast cancer risk factors assessed in the participants, high-density mammographic parenchymal patterns, as measured by the proportion of breast area composed of epithelial and stromal tissue, had the greatest impact on breast cancer risk. Of the breast cancers in this study, 28% were attributable to having 50% or greater breast density.

Transforming growth factor-beta receptor expression on endothelial cells: heterogeneity of type III receptor expression

Recent studies of whole animal responses have defined a role for circulating TGF-beta in the preservation and stabilization of microvascular endothelial function (Lefer et al. [1993] Proc. Natl. Acad. Sci. U.S.A., 90:1018-1022; Pfister et al. [1992] J. Exp. Med., 176:265-269). In order to determine which TGF-beta receptor types are responsible for this endothelial cell responsiveness, we used an affinity-labeling technique with 125I-TGF-beta 1 and -beta 2 to characterize TGF-beta receptors on five different endothelial cell cultures: early passage bovine lung and rat epididymal fat pad microvascular endothelial cells (BLMEC and REEC), established endothelial cell lines from bovine adrenal medulla capillaries (EJG), fetal bovine heart (FBHE), and bovine pulmonary artery (CPAE). Since it is known that endothelial cells from different parts of the vasculature vary with respect to cell surface antigen expression (McCarthy et al. [1991] Trends Pharmacol. Sci., 12:462-467; Augustin et al. [1994] Bioessays, 16:901-906), it is important to compare TGF-beta receptor expression on microvascular and macrovascular endothelial cells. We observed 85 kDa and 200-400 kDa labeled receptor bands and analyzed their relationship to the cloned Type II and III receptors using peptide antibodies. We used dithiothreitol and phosphoinositol-phospholipase C pretreatments to establish whether the 65 kDa labeled band which we observed corresponded to the Type I receptor or a glycophosphotidylinositol-linked binding protein. The results demonstrated that microvascular but not macrovascular endothelial cells express high levels of the Type III receptor. This differential expression of the Type III receptor indicates that distinct anatomical segments of the vasculature have distinct TGF-beta receptor profiles. The presence of the Type III receptor on micro- but not macrovascular endothelial cells may account for the reportedly different potency of TGF-beta 1 and TGF-beta 2 on these two endothelial cell types. Analysis of the 85 kDa and 65 kDa affinity-labeled bands revealed that all the endothelial cells express the Type II receptor and a band consistent with the presence of a dithiothreitol-sensitive Type I receptor. Two isoform-specific phosphoinositol-phospholipase C releasable TGF-beta binding proteins were also detected: a 60 kDa protein on one micro- (EJG) and one macro- (FBHE) vascular endothelial cell line and a 150/180 kDa protein on the macrovascular cell lines (FBHE and CPAE). These studies emphasize the heterogeneous nature of endothelial cells and underline the importance of using microvascular endothelial cells when examining TGF-beta responses related to microvascular function.

Effect of heat-moisture treatment on the structure and physicochemical properties of cereal, legume, and tuber starches

Native wheat, oat, lentil, yam, and potato starches were heat treated at 100 degrees C for 16 h at moisture contents between 10 and 30%. The heat treatment did not change granule size and shape. In oat starch, granules were less compactly packed after heat treatment. The X-ray diffraction intensities increased in wheat, oat, and lentil starches, but decreased in potato and yam. The X-ray patterns of wheat and oat starches remained unchanged, while those of lentil, potato, and yam starches became more cereal-like. In all starches, the swelling factor and amylose leaching decreased, being more pronounced in potato. Heat treatment induced complex formation between amylose and native lipids. Differential scanning calorimetry of the heat-treated samples showed a broadening of the gelatinization-temperature range and a shifting of the endothermal transition towards higher temperatures. These changes were more pronounced in potato starch. The gelatinization enthalpy of wheat, oat, and lentil starches remained unchanged, but those of potato and yam starches decreased on heat treatment. Heat treatment increased the 95 degrees C viscosity of wheat starch, but decreased those of oat lentil, potato, and yam starches. In all starches, thermal and shear stability increased after heat treatment. Acid hydrolysis decreased on heat treatment of wheat and lentil starches, but increased in oat, potato, and yam starches. However, in potato and yam starches, the foregoing trend was evident only during the first seven days of hydrolysis. Thereafter, acid hydrolysis was more pronounced in native than in heat-treated starches. The susceptibility towards hydrolysis by porcine pancreatic alpha amylase decreased on heat treatment of wheat and lentil starches, whereas increases were observed for oat, potato, and yam starches. The results indicated that the extent of starch-chain associations within the amorphous regions and the degree of crystalline order are altered during heat-moisture treatment. The magnitude of these changes were found to be dependent upon the moisture content during heat treatment and on the starch source.

An approach to studies of cancer subsequent to clusters of chronic fatigue syndrome: use of data from the Nevada State Cancer Registry

Chronic fatigue syndrome (CFS) has been increasingly associated with immune dysregulation, including depressed natural killer cell activity; this phenomenon is associated with increased susceptibility to cancer. Although anecdotal reports have suggested an association between CFS and cancer, particularly non-Hodgkin's lymphoma and brain cancer, there has been no a priori justification for evaluating such an association and no consideration of relevant parameters, such as length of latent period vs. tumor type. We reviewed data from the Nevada State Cancer Registry subsequent to a reported outbreak of a CFS-like illness in Nevada that occurred during 1984-1986. We concentrated on non-Hodgkin's lymphoma and brain/CNS tumors, with particular emphasis on persons 15-34 and 35-54 years of age. An upward trend in the incidence of brain/CNS tumors, which could be related to a national upward trend for this disease, was noted. No consistent trends were noted for non-Hodgkin's lymphoma. Because of the difficulties inherent in studies of cancer subsequent to various exposures, we evaluated the methodology for determining an association between outbreaks of CFS-like disease and cancer. We propose several approaches that should be considered in future studies for investigation of possible associations between CFS and cancer, including expected latent periods for specific tumors.

Hormone replacement therapy and breast cancer mortality in Swedish women: results after adjustment for 'healthy drug-user' effect

No change of breast cancer mortality has been reported previously after long-term hormone replacement therapy. A conceivable explanation for the apparent discrepancy between incidence and mortality may be selection bias due to lower prevalence of breast cancer in women who receive replacement hormones, compared with nonexposed women. We used a new approach to correct for bias due to this 'healthy drug-user effect,' by adjusting the external, population-based, mortality rates for such cases prevalent during the recruitment period of our cohort. In this cohort of some 23,000 Swedish women, who were prescribed various hormone replacement regimens, breast cancer mortality was analyzed after follow-up to 12 years. External analyses revealed overall standardized mortality ratios for breast cancer rising from 0.71 to 0.81, but not significantly different from unity, after adjustment procedures. In multivariate regression models, excluding prevalent cases in the cohort, women prescribed estradiol, conjugated estrogens, or an estrogen-progestin combination were not at a higher risk relative to those given other and weak estrogens, relative risks being 0.81 and 0.68, respectively. On the basis of the present analytical approach, we conclude that breast cancer mortality does not appear to be changed overall or in subgroups, despite increased incidence.

Dietary patterns associated with a low-fat diet in the national health examination follow-up study: identification of potential confounders for epidemiologic analyses

To identify systematically the nutrient and food group intakes associated with a low-fat diet, the authors used the detailed dietary information collected from 10,306 individuals aged 32-86 years in the 1982-1984 National Health Epidemiologic Follow-up Study. Intakes of vitamin C and percentages of calories from carbohydrates, dietary fiber, poultry, low-fat dairy products, fruits, vegetables, cereals, and whole grains were markedly higher, while intakes of protein, total fat, saturated fat, oleic and linoleic acids, cholesterol, sodium, all red meats, high-fat dairy products, eggs, nuts, white bread, fried potatoes, desserts, fats, and oils were much lower in the quartile with the lowest percentage of calories from fat. These dietary patterns associated with a low-fat diet were essentially constant across strata of age, sex, race, and socioeconomic status. This study suggests that individuals on a low-fat diet substitute certain carbohydrate-rich foods such as fruits and vegetables for fat. Given these associations between low-fat diets and other dietary factors independently associated with certain cancers, these dietary factors should be considered potential confounders in studies of dietary fat and these cancers.

Incidence of cancer among patients with rheumatoid arthritis

BACKGROUND

To evaluate hypotheses about the relationship between immune alterations and cancer, several investigators have determined cancer incidence in groups of patients with rheumatoid arthritis (RA), a chronic autoimmune disease. The primary finding has been an increased risk of hematopoietic cancers.

PURPOSE

In this study, we have attempted to refine estimates of the association between RA and subsequent development of specific cancers.

METHODS

We investigated site-specific cancer risk associated with RA in a population-based cohort study of 11683 Swedish men and women with a hospital (inpatient) diagnosis of RA. These case patients were identified from 1965 to 1983 and had follow-up through 1984 by computer linkage of the Swedish Hospital Inpatient Register to the National Swedish Cancer Registry (840 case patients with cancer) and the Swedish Registry of Causes of Death. Cancer risk was estimated by standardized incidence ratios (SIRs) for specific cancers.

RESULTS

For men and women overall, there were decreased risks for cancers of the colon (SIR = 0.63; 95% confidence interval [CI] = 0.5-0.9), rectum (SIR = 0.72; 95% CI = 0.5-1.1), and stomach (SIR = 0.63; 95% CI = 0.5-0.9) and an increased risk for lymphomas (SIR = 1.98; 95% CI = 1.5-2.6).

CONCLUSIONS

The reduced risk for colorectal cancer in patients with RA is consistent with previous studies of RA patients and with reports which state that use of nonsteroidal anti-inflammatory drugs may protect against the development of large bowel cancers. The excess of lymphomas also confirms a number of earlier investigations of RA patients.

Adhesion to and invasion of cultured human cells by Bartonella bacilliformis

Bartonella bacilliformis was tested for its ability to adhere to and invade tissue culture cell monolayers. The parasite was able to efficiently bind and penetrate human dermal fibroblasts, human laryngeal epithelium, and human umbilical vein endothelial cells. Exposure of the organism to immune serum prepared against a crude Bartonella extract containing cell wall and membranous material resulted in decreased ability of the parasite to invade host cells. There was also an overall reduction in the invasiveness of bartonellae and total host cell association when human laryngeal epithelial cells and human umbilical vein endothelial cells were preexposed to cytochalasin D, indicating an active involvement of host cells in the uptake of bartonellae. Transmission electron microscopy revealed the presence of bartonellae inside and outside intracellular vacuoles. These data suggest that a surface-associated factor is involved in the invasion process and that internalization of the parasite by host cells involves a microfilament-dependent process similar to phagocytosis.

Does chronic fatigue syndrome predispose to non-Hodgkin's lymphoma?

Chronic fatigue syndrome, an illness that frequently is associated with abnormalities of cellular immunity, has been reported anecdotally to be associated with an increased incidence of lymphoid hyperplasia and malignancy. This report describes an initial analysis of population-based cancer incidence data in Nevada, focusing on the patterns of non-Hodgkin's lymphoma prior to and subsequent to well described, documented outbreaks of chronic fatigue syndrome during 1984-1986. In a study of time trends in four age groups, the observed time trends were consistent with the national trends reported in the Surveillance, Epidemiology, and End Results Program. No statistically significant increase attributable to the chronic fatigue syndrome outbreak was identified at the state level. Additional studies are in progress analyzing the data at the country level, reviewing patterns in other malignancies, and continuing to monitor the cancer patterns over subsequent years.