Oral contraceptive and reproductive risk factors for ovarian cancer within sisters in the breast cancer family registry.

BACKGROUND: Oral contraceptive use has been consistently associated with a reduced risk of ovarian cancer in unrelated, average risk women; however little data exist on whether this benefit extends to higher risk women from cancer families. To examine this, we conducted family-based analyses using the Breast Cancer Family Registry. METHODS: We used generalised estimating equations to obtain the population average effect across all families (n=389 cases, n=5643 controls) and conditional logistic regression to examine within-family differences in a subset with at least two sisters discordant on ovarian cancer status (n=109 cases, n=149 unaffected sister controls). RESULTS: In the multivariable generalised estimating equation model there was a reduced risk of ovarian cancer for ever use of oral contraceptives compared with never use (OR=0.58, 95% CI: 0.37, 0.91), and in the conditional logistic model there was a similar inverse association; however, it was not statistically significant (OR=0.52, 95% CI: 0.23, 1.17). We examined this association by BRCA1/2 status and observed a statistically significant reduced risk in the non-carriers only. CONCLUSION: We observed a decreased risk of ovarian cancer with oral contraceptive use supporting that this association observed in unrelated women extends to related women at higher risk.

Tumour morphology predicts PALB2 germline mutation status.

BACKGROUND: Population-based studies of breast cancer have estimated that at least some PALB2 mutations are associated with high breast cancer risk. For women carrying PALB2 mutations, knowing their carrier status could be useful in directing them towards effective cancer risk management and therapeutic strategies. We sought to determine whether morphological features of breast tumours can predict PALB2 germline mutation status. METHODS: Systematic pathology review was conducted on breast tumours from 28 female carriers of PALB2 mutations (non-carriers of other known high-risk mutations, recruited through various resources with varying ascertainment) and on breast tumours from a population-based sample of 828 Australian women diagnosed before the age of 60 years (which included 40 BRCA1 and 18 BRCA2 mutation carriers). Tumour morphological features of the 28 PALB2 mutation carriers were compared with those of 770 women without high-risk mutations. RESULTS: Tumours arising in PALB2 mutation carriers were associated with minimal sclerosis (odds ratio (OR)=19.7; 95% confidence interval (CI)=6.0-64.6; P=5 × 10(-7)). Minimal sclerosis was also a feature that distinguished PALB2 mutation carriers from BRCA1 (P=0.05) and BRCA2 (P=0.04) mutation carriers. CONCLUSION: This study identified minimal sclerosis to be a predictor of germline PALB2 mutation status. Morphological review can therefore facilitate the identification of women most likely to carry mutations in PALB2.

Validation study of the LAMBDA model for predicting the BRCA1 or BRCA2 mutation carrier status of North American Ashkenazi Jewish women.

LAMBDA is a model that estimates the probability an Ashkenazi Jewish (AJ) woman carries an ancestral BRCA1 or BRCA2 mutation from her personal and family cancer history. LAMBDA is relevant to clinical practice, and its implementation does not require a computer. It was developed principally from Australian and UK data. We conducted a validation study using 1286 North American AJ women tested for the mutations 185delAG and 5382insC in BRCA1 and 6174delT in BRCA2. Most had a personal or family history of breast cancer. We observed 197 carriers. The area under the receiver operator characteristic (ROC) curve (a measure of ranking) was 0.79 [95% confidence interval (CI) = 0.77-0.81], similar to that for the model-generating data (0.78; 95% CI = 0.75-0.82). LAMBDA predicted 232 carriers (18% more than observed; p = 0.002) and was overdispersed (p = 0.009). The Bayesian computer program BRCAPRO gave a similar area under the ROC curve (0.78; 95% CI = 0.76-0.80), but predicted 367 carriers (86% more than observed; p < 0.0001), and was substantially overdispersed (p < 0.0001). Therefore, LAMBDA is comparable to BRCAPRO for ranking AJ women according to their probability of being a BRCA1 or BRCA2 mutation carrier and is more accurate than brcapro which substantially overpredicts carriers in this population.

Design of the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial.

The objectives of the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial are to determine in screenees ages 55-74 at entry whether screening with flexible sigmoidoscopy (60-cm sigmoidoscope) can reduce mortality from colorectal cancer, whether screening with chest X-ray can reduce mortality from lung cancer, whether screening men with digital rectal examination (DRE) plus serum prostate-specific antigen (PSA) can reduce mortality from prostate cancer, and whether screening women with CA125 and transvaginal ultrasound (TVU) can reduce mortality from ovarian cancer. Secondary objectives are to assess screening variables other than mortality for each of the interventions including sensitivity, specificity, and positive predictive value; to assess incidence, stage, and survival of cancer cases; and to investigate biologic and/or prognostic characterizations of tumor tissue and biochemical products as intermediate endpoints. The design is a multicenter, two-armed, randomized trial with 37,000 females and 37,000 males in each of the two arms. In the intervention arm, the PSA and CA125 tests are performed at entry, then annually for 5 years. The DRE, TVU, and chest X-ray exams are performed at entry and then annually for 3 years. Sigmoidoscopy is performed at entry and then at the 5-year point. Participants in the control arm follow their usual medical care practices. Participants will be followed for at least 13 years from randomization to ascertain all cancers of the prostate, lung, colorectum, and ovary, as well as deaths from all causes. A pilot phase was undertaken to assess the randomization, screening, and data collection procedures of the trial and to estimate design parameters such as compliance and contamination levels. This paper describes eligibility, consent, and other design features of the trial, randomization and screening procedures, and an outline of the follow-up procedures. Sample-size calculations are reported, and a data analysis plan is presented.

Pathobiologic characteristics of hereditary breast cancer.

Patients with hereditary breast cancer (HBC) present at a young age with breast cancers that show adverse pathological characteristics such as high nuclear grade, negative hormone receptor status, and high proliferation indices. Surprisingly, the clinical course has been reported to be comparable or improved compared with patients with nonhereditary breast cancer (non-HBC). To determine whether there are any molecular markers that might help explain this paradox between pathologically aggressive neoplasms in patients with HBC and the lack of extreme clinically aggressive disease, we studied several molecular parameters in a group of 34 breast cancer patients with mutations in either the BRCA1 or BRCA2 tumor suppressor genes and compared them with a group of 20 breast cancer patients with non-HBC. In general, patients with HBC had tumors that were of higher nuclear grade, contained a higher population of proliferating cells, showed increased expression of DNA topoisomerase II-alpha (topo II-alpha), lacked hormone receptors, and were more likely to show immunopositivity for the p53 tumor suppressor gene. Additionally, tumors from patients with HBC showed a decreased angiogenesis compared with controls. The decreased angiogenesis and the elevated expression of topo II-alpha (an anticancer drug target) may, in part, explain the lack of correlation between clinical course and histological characteristics in patients with HBC.

Response to radiation therapy and prognosis in breast cancer patients with BRCA1 and BRCA2 mutations.

BACKGROUND AND PURPOSE: The purpose of this study is to evaluate overall survival in BRCA1 or BRCA2 breast cancer patients, describe presenting stage, review histologic findings and evaluate response to radiotherapy. MATERIALS AND METHODS: A retrospective study was performed evaluating breast cancer patients with known mutations of BRCA1 or BRCA2. Patients from 12 different pedigrees were cross-referenced with the Utah Cancer Registry (UCR), histologic findings were verified and radiotherapy records were reviewed for acute response to treatment. Actuarial survival calculations were performed and patients were matched for age, date of diagnosis and tumor size. RESULTS: Thirty breast cancer patients with BRCA1 mutations were found to have 34 breast cancers (four had bilateral metachronous lesions) and 20 breast cancer patients with BRCA2 mutations were found to have 22 breast cancers (two had bilateral metachronous disease). The median age at diagnosis was 49 years (range 21-77 years) and 42 years (range 23-83 years), respectively, for BRCA1 and BRCA2 patients. Unusual histologic types of breast cancers were represented with 7% (4/56) medullary and 5% (3/56) lobular carcinomas. Complete staging was possible for 63% (35/56) of cancers. Stages I, II, III and IV represented 26, 63, 6 and 6% of cancers, respectively. The most severe radiation reaction was moist desquamation which was self-limiting and developed in 29% (6/21) of irradiated patients. The mean follow-up was 9.8 and 7.5 years for BRCA1 and BRCA2 cancers, respectively. Kaplan-Meier survival analysis demonstrated 5-year survival values of 75% for BRCA1 patients, 73% for BRCA2 patients, 70% for matched controls and 69% for UCR controls. No statistically significant differences were evident between the groups at 5 or 10 years. CONCLUSIONS: Despite their younger age at presentation, breast cancer patients harboring BRCAI or BRCA2 mutations present at a similar stage, display a normal acute reaction to radiotherapy and have a similar prognosis when compared with sporadic breast cancer patients.

Phase III randomized study to compare interferon alfa-2a in combination with fluorouracil versus fluorouracil alone in patients with advanced colorectal cancer.

PURPOSE: To compare the efficacy and toxicity profiles of a combination of fluorouracil (5-FU) and recombinant human interferon alfa-2a ([IFN alpha 2a] Roferon-A; Hoffmann-LaRoche, Basel, Switzerland) versus 5-FU alone in the treatment of advanced colorectal cancer (ACC). PATIENTS AND METHODS: A total of 245 previously untreated ACC patients were randomized to receive either IFN alpha 2a (9 million IU) subcutaneously (SC) three times weekly with 5-FU (750 mg/m2/d) by continuous intravenous (CIV) infusion on days 1 to 5 and then, after a 1-week hiatus, as a weekly IV bolus at the same dose (IFN/ 5-FU), or 5-FU alone at the same dose schedule (5-FU). RESULTS: There were no significant differences between IFN/5-FU and 5-FU alone in the overall response rate (24% v 17%, P = .2), duration of response (median, 6.4 v 8.1 months), time to response (plateau at 3 months), time to progressive disease ([PD] median, 4.8 v 4.9 months), or survival duration (median, 13.9 v 13.2 months). Toxicity profiles were not statistically different except for constitutional symptoms, which were more frequent and more severe with IFN/5-FU. More patients interrupted treatment for adverse events (AEs) with IFN/ 5-FU (34%) than with 5-FU alone (21%) (P = .03). The number of deaths (mostly unrelated to drug treatment) during the study (8%) was similar with both regimens. CONCLUSION: The combination IFN/5-FU produced a response rate, response duration, and survival duration similar to that of 5-FU alone. The addition of IFN to 5-FU in the doses and schedules used in this study did not provide any further benefit over 5-FU alone and cannot be recommended for patients with metastatic ACC. This study confirms the value of large prospective randomized clinical trials to determine the clinical value of regimens that emerge from smaller single-center phase II studies.

Phase II evaluation of amonafide in advanced sarcoma: a Southwest Oncology Group study.

Soft tissue sarcomas are generally resistant to most chemotherapeutic agents, and individuals with advanced disease have a poor prognosis. We evaluated amonafide, a new drug that has significant activity against several tumor cell lines, to determine its activity against sarcomas. Amonafide was administered to 18 patients with advanced soft tissue sarcoma (16 of whom had received prior chemotherapy) at a dose of 300 mg/m2 over 60 min daily for 5 days. Courses were repeated every 21 days. Toxicity was mild, but no responses were observed. We conclude that amonafide is not an active agent in previously treated, advanced soft tissue sarcomas in the dose and schedule utilized.

Iron absorption in hypotransferrinemic mice.

We used a unique animal model, the hypotransferrinemic (Htx) mouse, to examine the role of transferrin (Tf) in gastrointestinal iron uptake. Despite the absence of Tf, Htx animals hyperabsorb iron. Transfusion of red blood cells sufficient to normalize the hematocrit and reticulocyte count resulted in a return of iron absorption to normal values. These studies indicate that Tf does not play an obligate role in iron absorption, either as a carrier or as a humoral signal regulating absorption. Transfer of plasma or whole blood from Htx mice or from other animal models of iron hyperabsorption to normal mice did not cause an increase in iron absorption in recipient animals. Using the plasma or blood transfer approach, we have been unable to detect a humoral regulator of gastrointestinal iron absorption.

Effect of osmotic pressure on uptake of chemotherapeutic agents by carcinoma cells.

Intraperitoneal chemotherapy has been used to treat cancers which are confined to the abdominal cavity. Several variables which affect drug delivery into tumor cells have been identified, but the effect of osmotic pressure has not been studied. Tumor cell lines were used to evaluate the effect of fluid tonicity on drug uptake. HeLa cells and a murine teratoma cell line were suspended in solutions of tonicities 154, 308, and 616 mosM, each containing the same quantity of 5-fluorouracil, and uptake of the drug was measured at different intervals over 30 min. At all time points the amount of 5-fluorouracil taken up by cells in solutions of 154 mosM was greater than that in 310 mosM solutions, which was greater than the uptake in 616 mosM solutions, each by an average of 40-50%. Incorporation of drug into tumor cells was also assayed in vivo using a teratoma cell line propagated i.p. in mice. Tumor cell uptake of doxorubicin was increased to a similar extent when this drug was administered in hypotonic solutions of 154 mosM and was decreased by administration in hypertonic solutions of 465 mosM, as compared to solutions of 310 mosM. These results demonstrate that the uptake of chemotherapeutic agents into tumor cells is increased significantly when these drugs are infused in solutions of lower osmolalities, a finding which may be exploited in clinical situations.

Three cases of fatal cardiac tamponade following ventricular endocardial biopsy.

Three patients had perforation of the ventricular free wall and fatal cardiac tamponade following endocardial biopsy to evaluate congestive heart failure. The number of endocardial biopsies at this institution at the time of the third death was 2372, resulting in an overall mortality rate of 0.13%. Of the 2372 biopsies, 2136 (90%) were performed to evaluate cardiac graft rejection and 236 (10%) were performed for other reasons. All the patients who died belonged to the latter group. None of the cardiac transplant patients have had fatal ventricular perforation--a significant difference. At our institution, the frequency of mortality following endocardial biopsy in the noncardiac transplant patients is 1.3%. Patients who have ventricular endocardial biopsy of native hearts rather than transplanted hearts may be at increased risk for fatal perforation.

Carotid thrombosis following neck irradiation.

Therapeutic irradiation may accelerate atherosclerosis, increasing the risk of vascular stenosis or occlusion several to many years following radiation. However, intimal damage following irradiation may result earlier in thrombosis without stenosis. This report discusses three cases of carotid occlusion that occurred within 3 years of moderate dose irradiation. Angiographic studies showed that occlusion occurred in the absence of atherosclerotic stenosis. A review of the literature supports the conclusion that people who receive neck irradiation are at risk not only for the delayed development of diffuse atherosclerosis but also for thrombotic occlusion within months to several years. We suggest that patients who develop neurological symptoms or signs following neck irradiation, regardless of age, dose of radiation, or interval since radiation, should be evaluated for carotid or vertebral artery disease.

Effect of volume and pH on surface receptor number in macrophages.

Incubation of rabbit alveolar macrophages in hypo-osmotic solutions transiently increases cell volume and inhibits membrane internalization, resulting in an increase in surface receptor number. Since recent reports suggest that hypo-osmotic treatment decreases intracellular pH, and that reduced pH inhibits receptor internalization, pH was measured in hypo-osmotically treated macrophages. We found that cells incubated in iso-osmotic solutions of pH less than 7.2 exhibited a decrease in intracellular pH upon exposure to hypo-osmotic solutions, while cells in iso-osmotic solutions of pH greater than 7.2 had an increase in pH upon exposure to hypo-osmotic solutions. The relative increase in surface receptor number was unaffected by the initial pH or by the direction of change in pH. Incubation of cells in high K+/low Na+ hypotonic buffers induced a persistent increase in cell volume and surface receptor number. Cell volume and surface receptor number fell to baseline values after restoration of isotonicity by the addition of hypertonic sucrose. These manipulations had little effect on intracellular pH. We conclude that the inhibition of membrane internalization observed in cells exposed to hypo-osmotic solutions is independent of changes in intracellular pH. The inhibition of internalization observed in this system may be due directly to forces produced as a consequence of cell swelling.

Regulatory volume decrease in alveolar macrophages: cation loss is not correlated with changes in membrane recycling.

Alveolar macrophages regain their normal volume after swelling in hypo-osmotic solutions. This process, termed regulatory volume decrease (RVD), is initiated 3-5 minutes after exposure of cells to hypo-osmotic solutions, and by 30 min, near-normal volumes are attained. Volume decrease does not occur at 0 degrees C or in solutions in which Na+ has been replaced by K+, or Cl- by the impermeant anion gluconate. These results, as well as direct measurement of intracellular cations, indicate that decreases in cell volume result primarily from the loss of K+ and Cl- and are similar to RVD in lymphocytes. Kinetic analysis of cation loss, both by directly measuring changes in intracellular cation content and by assaying rubidium efflux, showed that cation loss occurred immediately upon media dilution. The rate of cation loss fit first-order kinetics and preceded both the initiation of volume decrease and the maximum increase in surface receptor number. These results suggest that the cation transporters responsible for RVD are located at the cell surface and that regulation of activity is not dependent on alterations in membrane movement.

Effect of hypo-osmotic incubation on membrane recycling.

Incubation of alveolar macrophages in hypo-osmotic media causes a time-and temperature-dependent increase in the number of surface receptors for three different ligands. Exposure of cells to solutions of 210 mOsM or less, at 37 degrees C but not at 0 degree C, resulted in an increase in the number of surface receptors for diferric transferrin, alpha-macroglobulin-protease complexes, and mannose-terminated glycoproteins. Upon media dilution at 37 degrees C, surface receptor number reached a maximum within 5 min and returned to near-normal values by 30 min. The increase in surface receptor number was the result of a decrease in the rate of internalization of receptors, either occupied or unoccupied. The rate of receptor exteriorization was unaltered by hypo-osmotic incubation of cells. The rate of fluid-phase pinocytosis was also inhibited upon incubation in hypo-osmotic solution. In experiments in which both receptor-mediated endocytosis and fluid phase pinocytosis were measured on the same samples, inhibition of both processes occurred with the same kinetics and to a similar extent. The rate of receptor-mediated endocytosis recovered to normal rates after 60 min in hypo-osmotic solutions, whereas the rate of fluid phase pinocytosis did not recover to the same extent.

Phorbol esters and calcium ionophores inhibit internalization and accelerate recycling of receptors in macrophages.

Exposure of macrophages to phorbol esters or the calcium ionophore A23187 increases the number of several surface receptors due to recruitment of receptors from internal pools (Buys, S. S., Keogh, E. A., and Kaplan, J. (1984) Cell 38, 569-576). We have examined the mechanism by which these agents increase surface receptor number. Cells which were preloaded with either fluid phase or receptor-mediated ligands did not lose ligand following exposure to ionophore or phorbol ester. The rate of movement of ligands to the lysosome was also unaffected. These results suggest that A23187 does not induce the fusion of ligand-containing compartments with the cell surface. Ionophore treatment did, however, produce a severalfold increase in the rate at which unoccupied receptors reappear on the cell surface. These results suggest that the compartment of receptors affected by the ionophore formed subsequent to the dissociation of ligand from receptor. The altered rate of receptor reappearance was transitory (90 s), and the increase in receptor number was subsequently maintained by a decrease in the rate of internalization. Changes in the rate of receptor internalization did not correlate with changes in the rate of fluid phase pinocytosis, suggesting that the effect on receptor internalization was selective.

Effect of phagocytosis on receptor distribution and endocytic activity in macrophages.

Phagocytosis requires the internalization of a significant fraction of the plasma membrane and results in the intracellular deposition of large particles. We evaluated the effect of phagocytosis on the cellular distribution of recycling receptors and uptake of ligand to determine whether phagocytosis affects receptor behavior. Phagocytosis of zymosan, latex particles, or IgG-coated red blood cells by rabbit alveolar macrophages did not decrease the number of cell surface receptors for transferrin, alpha 2-macroglobulin X protease complexes, maleylated proteins, or mannosylated proteins. The number of surface receptors for transferrin was also unaltered in J774 cells, a macrophage-like cell line. In both cell types extensive phagocytosis did not affect the rate of receptor-mediated endocytosis or the distribution of receptors between the endosome and the cell surface. However, fluid phase pinocytosis was reduced by phagocytosis. The major reduction appeared to be not in the rate of internalization but rather in the delivery of fluid to the lysosome. These results demonstrate that internalization of a significant amount of the plasma membrane during phagocytosis does not diminish the number of receptors on the cell surface and has no effect on receptor-mediated ligand uptake.

Fusion of intracellular membrane pools with cell surfaces of macrophages stimulated by phorbol esters and calcium ionophores.

Mouse tumor macrophages (J774) exposed to phorbol myristate acetate (PMA) exhibited a marked increase in cell spreading. Correlated with this phenomenon was an increase in the number of cell surface transferrin (Tf) receptors and a corresponding decrease in the number of Tf receptors located intracellularly in membrane-bound endosomes. Similar effects were noted when J774 cells were exposed to the calcium ionophore A23187. Rabbit alveolar macrophages did not respond to PMA but did respond to A23187 by increasing cell spreading, which was accompanied by increases on the cell surface of four different receptors. These results demonstrate that phorbol esters and calcium ionophores can induce a redistribution of cellular receptors.