Canadian pattern of care for anemia: comparison of chemotherapies in adjuvant breast cancer setting

Abstract #2118

Background: Anemia is a common side effect of chemotherapy in adjuvant breast cancer patients (pts) but its treatment may be inconsistent. Erythropoiesis-stimulating agents (ESAs) are the only alternative to blood transfusion in the treatment of chemotherapy-induced anemia, yet their appropriate use continues to be defined. The purpose of this study was to determine the frequency of anemia associated with adjuvant chemotherapy in Canadian breast cancer pts and to explore the corrective interventions which were undertaken.
 Methods: A retrospective chart review was conducted at 11 cancer centres in Ontario, Canada. Beginning on September 1, 2004 data were collected for 60 consecutive cases of adjuvant breast cancer at each centre, giving a total of 620 patients. Chemotherapy consisted mainly of FEC100, AC-T, AC, CEF, FEC50, and AC-T Dose Dense. Overall, 8% of pts were enrolled in a clinical trial and 76% received adjuvant radiotherapy. Hemoglobin level (Hb), supportive therapy (antibiotics, GCSF, ESA, and transfusion) and type of chemotherapy were recorded at each cycle.
 Results: The median pt age was 53. The mean baseline Hb was 132.8 (92.0-163) g/L, 11.6% of pts had Hb<120g/L. During the course of chemotherapy, the percentage of subjects with Hb<120 at least once was 55.8%, Hb<110 was 37.8%, Hb<100 was 21.2 % and Hb<90 was 11.5%, with a median of 36.0, 52.5, 71.0, and 75.0 days to develop anemia respectively. For pts whose Hb dropped below 100 g/L, 45.4% occurred after the 1st cycle, 68.8% after the 2nd, 83.7% after the 3rd, and 92.2% after the 4th chemotherapy cycle. Overall, 13.2% of subjects received prophylactic antibiotics, 26.3% were supported by G-CSF, 9.0% received an ESA (epoetin alfa) during their chemotherapy and 7.4% were transfused. The rates of anemia as well as means of intervention are summarized in Figure 1. ESAs were not used prophylactically in this setting.
 Conclusions: In Canada, breast cancer patients receiving adjuvant chemotherapy commonly become anemic during their course of treatment. This retrospective study demonstrated that ESAs play an important role in the management of anemia in the adjuvant setting. Canadian treatment guidelines recommend that ESA therapy be initiated when Hb <100 g/L. Our finding shows that ∼42% of patients whose Hb dropped below 100g/L were treated with ESAs, suggesting that ESAs were not overused in Canadian practice.
 


Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2118.

149. Smad3 DOSAGE INFLUENCES TESTICULAR MATURATION

Activin A, a TGF-beta superfamily ligand which signals via Smad2 and Smad3, is critical for normal mouse testis development and quantitatively normal sperm production. Whereas activin enhances immature Sertoli cell proliferation (1), excessive activin production causes Sertoli cell tumours (2); this is alleviated when mice lack Smad3 (3). Sertoli cells exhibit developmentally regulated Smad utilization in activin signalling. Immature Sertoli cells signal via Smad3 while the onset of Smad2-mediated signal transduction correlates with Sertoli cell maturation (4). This change coincides with decreased testicular Smad3 production at puberty and a shift in follicle stimulating hormone (FSH)-induced Smad transcription, from Smad3 in 6 dpp (days post partum) Sertoli cells to Smad2 in 15 dpp cells. These findings suggest that Smad3 is more important for testis development than adult spermatogenesis. To test this hypothesis, we examined testis development in Smad3+/– and Smad3–/– mice. At 7 dpp, testis weight and cord diameter were reduced in Smad3–/–mice, indicating impaired Sertoli cell proliferation. Levels of FSH, a potent Sertoli cell mitogen, were unaltered. Histological analysis revealed advanced spermatogenesis in heterozygous mice, with round spermatids already present at 16 dpp. Quantitative PCR also identified advanced Sertoli and germ cell maturation in Smad3+/– mice, while Leydig cell maturation appeared unaltered. Adult Smad3+/– and Smad3–/– mice were fertile, but had smaller testes. This is the first study relating Smad3 levels to puberty onset and identifies the Smad3+/– mouse as a model of peripheral precocious puberty with otherwise normal physiological status, i.e. no gonadal tumours and normal FSH levels. These results demonstrate that FSH influences testis growth and maturation by regulating Smad3 expression and highlights the importance of testing whether environmental factors, toxicants and endocrine disruptors affect Smad3 expression, thereby leading to altered testis development.

Changing health behaviors to improve health outcomes after angioplasty: a randomized trial of net present value versus future value risk communication

Patients who have undergone angioplasty experience difficulty modifying at-risk behaviors for subsequent cardiac events. The purpose of this study was to test whether an innovative approach to framing of risk, based on 'net present value' economic theory, would be more effective in behavioral intervention than the standard 'future value approach' in reducing cardiovascular morbidity and mortality following angioplasty. At baseline, all patients completed a health assessment, received an individualized risk profile and selected risk factors for modification. The intervention randomized patients into two varying methods for illustrating positive effects of behavior change. For the experimental group, each selected risk factor was assigned a numeric biologic age (the net present value) that approximated the relative potential to improve current health status and quality of life when modifying that risk factor. In the control group, risk reduction was framed as the value of preventing future health problems. Ninety-four percent of patients completed 2-year follow-up. There was no difference between the rates of death, stroke, myocardial infarction, Class II-IV angina or severe ischemia (on non-invasive testing) between the net present value group and the future value group. Our results show that a net present risk communication intervention did not result in significant differences in health outcomes.

The effects of dietary obesity on protein expressions of insulin signaling pathway in rat aorta

The deleterious effects of obesity on insulin response in vasculature may be due to changes in various components of insulin signaling pathway. Therefore, this study was designed to investigate effects of dietary-obesity, removal of palatable diet, and fenofibrate treatment on protein expressions of insulin signaling pathway in rat aorta. Adult male Wistar rats were fed either standard chow or a palatable diet (untreated obese animals) for 15 weeks. Another group of rats were fed the palatable diet for 8 weeks followed by standard chow for further 7 weeks, while a further group were fed the palatable diet for 15 weeks and were dosed with fenofibrate (50 mg/kg/day) for the last 7 weeks. Untreated obese animals had significantly higher body weight than other three groups (p < 0.05 for all). There were no significant differences between IR-β, IRS1 and IRS2, Akt, Shc, and ERK1/2 levels in chow-fed and untreated obese animals, while PI 3-kinase level were significantly (p < 0.0001) decreased in untreated obese animals. Chronic removal of palatable diet completely reversed the levels of PI 3-kinase to the normal while, fenofibrate treatment further reduced PI 3-kinase levels. On the other hand, there was a significant (p < 0.05) increase in eNOS in untreated obese animals compared with chow-fed controls. This effect was reversed by removal of palatable diet and fenofibrate treatment. These data suggest that dietary-obesity selectively inhibits PI 3-kinase while, removal of obesity-inducing diet improves PI 3-kinase levels which may have a role in vascular reactivity.

Molecular epidemiology demonstrated three emerging clusters of human immunodeficiency virus type 1 subtype B infection in Hong Kong

We conducted a molecular epidemiological study on newly diagnosed human immunodeficiency virus type 1 (HIV-1)-infected patients in Hong Kong to identify the epidemiological linkage of HIV-1 infection in the locality. Reverse transcription polymerase chain reaction (RT-PCR) for HIV-1 was performed on newly diagnosed HIV-1-positive sera collected from January 2002 to December 2006. PCR products correspond to the env C2V3V4 region and gag p17/p24 junction of the HIV-1 genome were nucleotide sequenced. Phylogenetic analyses performed on the acquired nucleotide sequences revealed that CRF01_AE and subtype B were the two dominant HIV-1 subtypes. Analyses also demonstrated the presence of three emerging HIV-1 clusters among the subtype B sequences in Hong Kong. Individual cluster possesses a unique cluster-specific amino acid signature for identification. Data show that one of the clusters (Cluster I) is rapidly expanding. In addition to the unique cluster-specific amino acid signature, the majority of sequences in Cluster I harbor a 6-amino acid insertion at the gag p17/p24 junction in a region that is thought to be closely associated with HIV-1 infectivity.

Cytokine gene polymorphism and progression of renal and cardiovascular diseases

Cytokines are important modulators of inflammation. The balance between pro- and anti-inflammatory cytokines determines whether the intensity of inflammatory response is within physiological limits or in the pathological range. The cytokine network is highly complex, containing interactive cascades of gene activation and suppression. Both chronic kidney disease (CKD) and end-stage renal disease (ESRD) are characterized by elevated levels of proinflammatory cytokines and markers of inflammation. Cytokines may modulate the risk for progression of renal disease and the susceptibility to cardiovascular disease (CVD). Polymorphisms of cytokine genes may influence gene transcription and cytokine secretion and thereby modulate the risk of progression of renal and CVDs. The observed inconsistencies in the data regarding associations between single-nucleotide gene polymorphisms (SNPs) and their presumed phenotypic expression emphasize the need to recognize several conceptual and methodological aspects such as haplotypic rather than single SNP variations and the influence of pathway genes with synergistic or antagonistic effects that ultimately determine the phenotype. It is conceivable that when a patient with a high-risk cytokine genotype develops CKD, the risk for CVD is increased. Early interventions in CKD patients with high-risk genotypes may slow the progression of renal disease and also decrease CV mortality and morbidity.

Detection of circulating tumor cells (CTCs) in patients with hepatocellular carcinoma (HCC)

15037

Background: Allard et al. (2004) has established the accuracy, sensitivity, reliability and linearity of circulating tumor cells (CTCs) detection using the CellSearch System. 57% prostate cancers, 37% breast cancers, 37% ovarian cancers, 30% colorectal cancers, and 20% lung cancers specimens had >= 2 CTCs per 7.5 mL of blood. Only 0.3% healthy non-malignant disease subjects had >= 2 CTCs per 7.5 mL of blood. Cristofanilli et al.(2004,2005) have shown that CTCs at baseline and first follow-up were a significant prognostic factor for survival in metastatic breast cancer patients. However, HCC data on CTCs are not available. Methods: 20 locally advance or metastatic HCC patients who had not received prior treatment had been recruited after informed consent and 7.5 mL of blood were collected using the CellSave Preservative tubes (Veridex LLC, Raritan, NJ) that prevents CTCs degradation. The CellSearch system (Veridex LLC) similar to the previous studies was used to analyze the specimen. The CellSearch system consists the CellPrep system, the CellSearch Epithelial Cell Kit, and the CellSpotter Analyzer. All the procedures and interpretation of results followed closely with the quality control procedure of Veridex LLC including accreditation of trained laboratory personnel. Results: 13/20 (65%) had locally advanced disease and the rest had metastatic HCC. All patients had multiple lesions. 9/20 (45%) patients had detectable CTCs, 7/20 (35%) had >= 2 CTCs, and about 5/20 (20%) had 5 or more CTCs. For locally advanced HCC 4/13 (31%) patients had >= 2 CTCs per 7.5 mL of blood. For HCC patients with metastatic diseases 3/7 (43%) patients had >= 2 CTCs per 7.5 mL of blood. Conclusions: HCC patients with locally advance or metastatic disease had detectable CTCs in 7.5 mL of blood. We expected that the performance of CTCs in HCC is similar to that of breast cancer. Future study of using CTCs as prognostic factor at baseline and during treatment for HCC is being planned.

No significant financial relationships to disclose.

Reconsolidation and memory infidelity in Lymnaea

Lymnaea stagnalis were operantly conditioned to not perform aerial respiratory behaviour in a specific context (i.e. context-1). The memory for this learned response was reactivated 3 days later in context-1. During the 1 h reconsolidation period following memory reactivation, randomly picked snails were either maintained in context-1 or exposed to a new context (i.e. context-2). One hour later in the post-reconsolidation period, snails in context-1 were placed for 1 h in context-2 and vice-versa. In neither the hypoxic reconsolidation nor the post reconsolidation periods did snails receive a reinforcing stimulus when they opened their pneumostome. All snails were blindly tested for memory 24 h later period in context-2. Only those snails that had been exposed to context-2 during the reconsolidation period exhibited 'memory' for context-2. That is, memory infidelity was observed. Snails exposed to context-2 in only the post-reconsolidation period did not show memory for context-2. The immediate cooling of snails after their exposure to the new context in the reconsolidation period blocked the formation the implanted memory. Snails trained in context-1 and exposed to context-2 in the consolidation period only, also did not have memory for context-2. However, the memory for context-1 could still be recalled following successful implantation of the 'new' memory. All data presented here are consistent with the notion that during the reconsolidation process memory can be updated.

The health and health behaviors of young men who have sex with men

PURPOSE

To describe the range of health and mental health problems for which young men who have sex with men (YMSM) may be at risk.

METHODS

An audio-computer-assisted survey was administered to a large, ethnically diverse sample of 526 YMSM (aged 18-24 years) recruited from bars, clubs, and other social venues using a venue-based probability sampling method.

RESULTS

Subjects reported a range of health and mental health problems, and involvement in health-compromising behaviors, such as overweight/obesity, depression, and suicidal thoughts/attempts, and many were found to have high rates of sexually transmitted infections. Moreover, many reported not having insurance coverage and/or limited access to care.

CONCLUSIONS

Many of the health concerns and risks reported by these young men are preventable and can be addressed by any number of sectors, including health care and social service providers, religious organizations, schools, and employers.

Stressful stimuli modulate memory formation in Lymnaea stagnalis

Stress has been shown to be a strong modulator of learning and memory in animals. We employ operant training of aerial respiratory behaviour in our model system, the pond snail Lymnaea stagnalis, to show that application of an acute consistent physical stressor enhances memory formation. A single 30 min operant conditioning training session, which normally results in intermediate-term memory (ITM) persisting 3h, results in long-term memory (LTM) persisting 24h if immediately preceded or followed by a stressor, for example a 30s exposure to 25 mM KCl. Other physical stressors (0.3% quinine-HCl or quick cooling and warming) similarly enhance memory formation. The memory is context specific and is not seen after the application of too much or too little stress. The memory can be extinguished by exposing snails to the hypoxic training environment and withholding reinforcing stimuli. The LTM that results from 30 min of training and stressor exposure is dependent on de novo protein synthesis and gene transcription in a single neuron, RPeD1. Because the soma of RPeD1 must be present for memory augmentation by the application of a stressor we are well placed for future investigations to directly determine the specific molecular alterations by which stress primes the formation of LTM.

Ribosomal protein S24 gene is mutated in Diamond-Blackfan anemia

Diamond-Blackfan anemia (DBA) is a rare congenital red-cell aplasia characterized by anemia, bone-marrow erythroblastopenia, and congenital anomalies and is associated with heterozygous mutations in the ribosomal protein (RP) S19 gene (RPS19) in approximately 25% of probands. We report identification of de novo nonsense and splice-site mutations in another RP, RPS24 (encoded by RPS24 [10q22-q23]) in approximately 2% of RPS19 mutation-negative probands. This finding strongly suggests that DBA is a disorder of ribosome synthesis and that mutations in other RP or associated genes that lead to disrupted ribosomal biogenesis and/or function may also cause DBA.