Phase II Trial of Definitive Therapy for Osseous Oligometastases in Breast Cancer

PURPOSE/OBJECTIVE(S)

Phase II data for consolidative local therapy for oligometastatic disease demonstrated improved outcomes for various malignancies. However, a randomized phase II study of oligometastatic breast cancer patients testing predominantly ablative dose radiotherapy (RT) did not demonstrate progression-free survival (PFS) benefit. We conducted a single-arm phase II trial evaluating local therapy as part of the multidisciplinary management of breast cancer patients with limited bone metastases.

MATERIALS/METHODS

Patients with synchronous (n = 15) and metachronous (n = 15) oligometastatic breast cancer involving ≤3 osseous sites were enrolled from July 2009 to April 2016 and treated to a total of 44 bone metastases. The trial closed early due to slow accrual. Following ≤9 months of systemic therapy, local therapy entailed surgery (n = 3) or RT delivered via conventional fractionation (≥60 Gy, n = 36) or stereotactic technique (27 Gy/3 fractions for spine mets, n = 6). When indicated, RT to the primary was delivered concurrently (n = 15). The primary endpoint was to determine PFS. Secondary endpoints were overall survival (OS), local control (LC) and toxicity. Outcomes were evaluated with Kaplan-Meier and univariate Cox proportional hazards analyses.

RESULTS

Of the 30 patients included in the trial, 23 (77%) had ER+ or PR+/HER2- disease, 4 (13%) had Her2+ disease, and 3 (10%) were triple negative. Median age was 53, and 20 patients (67%) presented with 1 distant metastasis. A total of 21 patients (70%) experienced disease progression at a median 20.5 months (IQR: 8.2-41.2), including 5 local failures among 44 treated bone metastases (11%). At a median follow-up of 76.7 mon (IQR: 45.4-108.8), the median PFS was 37.8 mon, with 2- and 5-year rates (95% CI) of 60% (45-80%) and 32% (19-55%), respectively. The 2- and 5-year OS rates were 93% (85-100%) and 64% (48-85%), respectively, and the 2- and 5-year LC rates were 91% (80-100%) and 71% (51-98%). For patients who achieved LC, median PFS was 47.7 months (IQR 12.2-73.0). Twenty-one patients (70%) received cytotoxic chemotherapy with or without endocrine therapy for newly diagnosed oligometastatic disease. Nine patients (30%) were still alive with no evidence of disease (NED) at a median 96.9 mon (range: 47.7-158.6). PFS was worse among triple negative patients (p = 0.03), with no difference based on synchronous vs non-synchronous presentation (p = 0.10), receipt of cytotoxic chemotherapy prior to definitive therapy (p = 0.08) or Her2+ status (p = 0.21). There were no Grade ≥3 adverse events.

CONCLUSION

Definitive, predominantly conventionally fractionated local therapy was associated with long-term NED status for 30% of patients with oligometastatic breast cancer involving osseous sites, with minimal treatment-associated toxicity. Developing randomized trials for breast cancer subsets may warrant consideration of standard fractionation regimen data and the need for strategies to identify patients who may benefit from definitive local therapy.

Prospective Clinical Trial of Premastectomy Radiotherapy Followed by Immediate Breast Reconstruction for Operable Breast Cancer

PURPOSE/OBJECTIVE(S)

Radiation delivered prior to mastectomy and autologous breast reconstruction may avoid the adverse effects of radiation on autologous donor tissue while providing the psychologic benefit of immediate reconstruction. We aimed to study the feasibility of premastectomy radiation therapy (PreMRT).

MATERIALS/METHODS

A total of 50 women enrolled in a prospective trial of preoperative radiation to the breast and regional nodes followed by mastectomy with axillary evaluation and immediate breast reconstruction. The trial was embedded in a randomized trial of hypofractionated versus conventionally fractionated regional nodal irradiation (NCT02912312). Eligible women enrolled from 2018-22, had cT0-T3 N0-3 breast cancer, and a pre-operative recommendation for radiation. The primary outcome was frequency of complete free flap loss. Mastectomy skin flap necrosis was assessed by validated SKIN grading score. The Satisfaction with Breast Cosmetic Outcomes Scales evaluated patient satisfaction with cosmetic result. Descriptive statistics and 95% exact confidence intervals were calculated.

RESULTS

One patient withdrew prior to any treatment and one elected not to have breast reconstruction. Median age of the 48 women completing PreMRT and reconstruction was 48 [range 31-72]. Most had ER-positive HER2-negative (77%), cT3 (54%) or cT2 (38%), cN1 (79%) disease and received 50 Gy in 25 fractions (n = 24) or 40.05 Gy in 15 fractions (n = 23). Four received 10-16 Gy internal mammary or infraclavicular boost. 35% VMAT, 48% matched photon-electron, and 17% partially-wide-tangent technique. Median time to surgery was 23 days [14-85]. Skin reaction delayed surgery for one patient. Most had skin-sparing mastectomy (92%) and axillary lymph node dissection (67%). 12 surgeons performed the reconstructions: 35 deep inferior epigastric perforators; 4 profunda artery perforator; 2 muscle-sparing transverse rectus abdominis myocutaneous; 1 latissimus dorsi (LD); 2 LD/implant; 2 LD/tissue expander (TE); and 2 subpectoral (SP) TE. There were no complete flap losses. Two patients (4.4%, 95% CI 0.5%-14.8%) with free flaps had partial flap loss with revision surgery. Both patients with SP TEs had infections and unplanned reoperation. The protocol was subsequently amended to not allow SP TE reconstruction. Eight patients had skin flap necrosis: 5 partial and 3 full thickness necrosis; only 1 required operative debridement. Seven had pathologic complete response. At six months 19/31 (61%) reported being "quite a bit" or "very much" satisfied with how they looked in the mirror clothed. There are no recurrences with a median follow up of 33 months [5-119].

CONCLUSION

Radiation treatment of the breast and lymph node basins prior to mastectomy with immediate autologous reconstruction is feasible. There were no autologous flap loses and complication rates are similar to reconstruction after radiation series. This promising strategy reduces time to autologous reconstruction and merits further prospective study.

Addition of Metastasis-Directed Therapy to Standard of Care Systemic Therapy for Oligometastatic Breast Cancer (EXTEND): A Multicenter, Randomized Phase II Trial

PURPOSE/OBJECTIVE(S)

Prior retrospective and prospective evidence have suggested a potential survival benefit of adding metastasis-directed therapy (MDT) to standard of care systemic therapy for oligometastatic breast cancer. This has led to the increased utilization of MDT in this setting despite the lack of randomized evidence to support this approach. Furthermore, the recent presentation of NRG-BR002 has questioned the value of MDT. Thus, we evaluated whether the addition of MDT to systemic therapy improves PFS in oligometastatic breast cancer.

MATERIALS/METHODS

EXTEND (NCT03599765) is a phase II randomized basket trial for multiple solid tumors testing whether the addition of MDT improves PFS. The primary endpoint was pre-specified to be independently assessed and reported for the breast basket when a minimum of 6 months of follow-up had been reached. Patients with ≤5 metastases were randomized to standard of care systemic therapy with or without MDT. The choice of systemic therapy was at the discretion of the treating medical oncologist. Number of metastatic lesions and prior lines of systemic therapy for metastatic disease were used as stratification variables pre-randomization. The primary endpoint was progression-free survival (PFS) defined as time to randomization to date of clinical or radiographic progression or death. The study was designed to have 80% power to detect an improvement in median PFS from 18 to 36 months, with a type I error of 0.1.

RESULTS

Between September 2018 to July 2022, 43 patients were randomized. 22 patients were assigned to the MDT arm, and 21 patients to the no MDT arm. Three patients were not evaluable. The MDT arm patients were older vs the no-MDT arm patients (median 61.5 years vs 48 years, p = 0.01). Otherwise, the arms were well-balanced. Overall, 8 patients had triple negative disease (18.6%), and 12 patients (30%) had de novo metastatic disease. Of those patients with de novo presentation randomized to MDT, all except one had the primary tumor treated with surgery and radiation. At a median follow-up of 19.4 months, 20 events were observed. Among the 40 evaluable patients, there were 5 deaths (3 in the MDT arm and 2 in the no MDT arm). There was no difference in PFS between the MDT and no MDT arms (median 15.6 v 24.9 months, p = 0.66). Similarly, there was no difference in the secondary endpoint of time to new metastatic lesion appearance between the MDT and no MDT arms (median 15.6 months vs not reached, p = 0.09). Two grade 3 toxicities were observed in the MDT arm, and 1 in the no MDT arm. Further analysis of correlative translational biomarkers, including immune markers and ctDNA, are ongoing.

CONCLUSION

The addition of MDT to standard of care systemic therapy did not improve PFS or time to new metastatic lesion in patients with oligometastatic breast cancer. This data coupled with the recently presented NRG-BR002 results, suggests there is no benefit to MDT in an otherwise unselected oligometastatic breast cancer population.

Evaluation of the ESMO-Magnitude of Clinical Benefit Scale version 1.1 (ESMO-MCBS v1.1) for adjuvant radiotherapy in breast cancer

BACKGROUND

The European Society of Medical Oncology (ESMO) has suggested using the ESMO-Magnitude of Clinical Benefit Scale (MCBS) to grade the magnitude of clinical benefit of cancer therapies. This approach has not been applied to radiation therapy (RT) yet. We applied the ESMO-MCBS to experiences describing the use of RT to assess (1) the 'scoreability' of the data, (2) evaluate the reasonableness of the grades for clinical benefit and (3) identify potential shortcomings in the current version of the ESMO-MCBS in its applicability to RT.

MATERIALS AND METHODS

We applied the ESMO-MCBS v1.1 to a selection of studies in radiotherapy that had been identified as references in the development of American Society for Radiation Oncology (ASTRO) evidence-based guidelines on whole breast radiation. Of the 112 cited references, we identified a subset of 16 studies that are amenable to grading using the ESMO-MCBS.

RESULTS

Of the 16 studies reviewed, 3/16 were scoreable with the ESMO tool. Six of 16 studies could not be scored because of shortcomings in the ESMO-MCBS v1.1: (1) in 'non-inferiority studies', there is no credit for improved patient convenience, reduced patient burden or improved cosmesis; (2) in 'superiority studies' evaluating local control as a primary endpoint, there is no credit for the clinical benefit such as reduced need for further interventions. In 7/16 studies, methodological deficiencies in the conduct and reporting were identified.

CONCLUSIONS

This study represents a first step in determining the utility of the ESMO-MCBS in the evaluation of clinical benefit in radiotherapy. Important shortcomings were identified that would need to be addressed in developing a version of the ESMO-MCBS that can be robustly applied to radiotherapy treatments. Optimization of the ESMO-MCBS instrument will proceed to enable assessment of value in radiotherapy.

Decisive points for pregnancy losses in beef cattle

Beef cattle producers rely on each of their cows to produce a marketable calf each year to maintain a sustainable operation. Within the first month of gestation, pregnancy failures have been recorded to be upwards of 40-50%. From fertilisation to birth, there are numerous factors contributing to pregnancy failure. From the beginning of gestation oocyte competence is often a large factor impacting fertility as the dam contributes all mRNA for initial embryo development. Other factors contributing to early embryonic infertility include hormonal concentration and heat stress. After the embryo enters the uterus, it becomes critical for the uterus to be receptive to the developing conceptus. The embryo then begins to elongate and secrete interferon-tau to initiate maternal recognition of pregnancy; a requirement to establish and maintain bovine pregnancies. After a pregnancy completes these steps, placentation actively begins around day 22 of pregnancy and lasts until organogenesis. The fetal phase follows the embryonic phase where disease and/or toxins are often the cause of pregnancy failure at this period. However, fetal mortality has been reported to occur in less than 10% of pregnancies. Understanding of the many factors influencing infertility needs to be further investigated to increase pregnancy success in beef cattle.

Co-crystals of tetrahaloauric acid and 1,3,5-(methylacetamide)benzene-based tectons: consistent trapping of high energy molecular conformation

Co-crystal engineering is a promising method to create new classes of advanced materials. Co-crystal structure prediction is more challenging when one or more of the lattice constituents (tectons) are flexible...

An assessment of the current status of children's toothpaste in Australia

BACKGROUND

Despite recommendations that pre-school children use toothpaste containing 500-550 ppm of fluoride, there has been an increase in non-fluoridated toothpastes marketed for children. This study investigated children's toothpaste in Australia.

METHODS

A comprehensive audit of all toothpastes marketed for pre-school children and available in store in the Macarthur region of NSW, Australia, was carried out. All toothpastes available for purchase were obtained and examined; size and price were catalogued, along with ingredient lists and fluoride levels.

RESULTS

One hundred and seven individual toothpastes were identified in the audit, with 67 (62.6%) containing no fluoride. Of the 40 fluoridated toothpastes, only 11 (10.3%) contained the recommended level of fluoride of 500-550 ppm. Twenty-two (20.6%) of all toothpastes were made in Australia, all of which were non-fluoridated. Six (5.6%) of the toothpastes studied contained excessive levels of fluoride (1350-1500 ppm). Seventeen of the 20 least expensive toothpastes contained fluoride, while 18 of the 20 most expensive toothpastes were non-fluoridated.

CONCLUSIONS

Despite expert recommendations, the majority of children's toothpaste available in Australia contains either no fluoride or the wrong levels of fluoride. Further study is needed to determine why this change is occurring and what is influencing the increase in non-fluoride toothpastes on the market.

Baseline factors predicting a response to neoadjuvant chemotherapy with implications for non-surgical management of triple-negative breast cancer

BACKGROUND

Patients with triple-negative breast cancer (TNBC) and a pathological complete response (pCR) after neoadjuvant chemotherapy may be suitable for non-surgical management. The goal of this study was to identify baseline clinicopathological variables that are associated with residual disease, and to evaluate the effect of neoadjuvant chemotherapy on both the invasive and ductal carcinoma in situ (DCIS) components in TNBC.

METHODS

Patients with TNBC treated with neoadjuvant chemotherapy followed by surgical resection were identified. Patients with a pCR were compared with those who had residual disease in the breast and/or lymph nodes. Clinicopathological variables were analysed to determine their association with residual disease.

RESULTS

Of the 328 patients, 36·9 per cent had no residual disease and 9·1 per cent had residual DCIS only. Patients with residual disease were more likely to have malignant microcalcifications (P = 0·023) and DCIS on the initial core needle biopsy (CNB) (P = 0·030). Variables independently associated with residual disease included: DCIS on CNB (odds ratio (OR) 2·46; P = 0·022), T2 disease (OR 2·40; P = 0·029), N1 status (OR 2·03; P = 0·030) and low Ki-67 (OR 2·41; P = 0·083). Imaging after neoadjuvant chemotherapy had an accuracy of 71·7 (95 per cent c.i. 66·3 to 76·6) per cent and a negative predictive value of 76·9 (60·7 to 88·9) per cent for identifying residual disease in the breast and lymph nodes. Neoadjuvant chemotherapy did not eradicate the DCIS component in 55 per cent of patients.

CONCLUSION

The presence of microcalcifications on imaging and DCIS on initial CNB are associated with residual disease after neoadjuvant chemotherapy in TNBC. These variables can aid in identifying patients with TNBC suitable for inclusion in trials evaluating non-surgical management after neoadjuvant chemotherapy.

Abstract P2-11-12: Prospective comparison of late toxicity and cosmetic outcome after accelerated partial breast irradiation with conformal external beam radiotherapy or single-entry multi-lumen intracavitary brachytherapy

Purpose/Objective(s):

To prospectively compare late toxicity after accelerated partial breast irradiation (APBI) with 3D-conformal external beam radiotherapy (3D-CRT) or single-entry multi-lumen intracavitary brachytherapy.

Patients/Methods:

Two hundred eighty-one patients with pTis or pT2N0 (≤3.0 cm) breast cancer treated with segmental mastectomy were prospectively enrolled on a multi-institution observational protocol from 12/2008 – 8/2014. Patients were enrolled and treated at primary, satellite, and affiliated academic institutions. APBI was delivered using 3D-CRT or with a Contura®, MammoSite®, or SAVI® brachytherapy catheter. 3D-CRT patients were treated to 34.0 Gy (7%) or 38.5 Gy (93%) at 3.4-3.85 Gy/fx BID and brachytherapy patients were treated to 34.0 Gy at 3.4 Gy/fx BID. Per protocol, patients were clinically evaluated at 2, 6, 12, 18, and 24 months and then annually. At each clinical evaluation the radiation oncologist scored cosmetic outcome (excellent/good/fair/poor according to the Harvard Cosmesis Scale), toxicity (seroma/infection/fat necrosis/pain/telangiectasia/radiation dermatitis/hyperpigmentation/hypopigmentation/fibrosis/induration/edema/other according to CTCAE v3.0) and recurrence status.

Results:

The median age was 61 years. Of 281 patients, 211 (75%) had invasive breast cancer and 70 (25%) had in situ disease. Among patients with invasive disease, 90% were HR+/HER2-, and among patients with in situ disease, 83% were HR+. APBI was delivered with 3D-CRT in 29 (10%) patients and with single-entry multi-lumen intracavitary brachytherapy in 252 (90%) patients. Among the brachytherapy patients, APBI was delivered with the SAVI®, Contura®, and MammoSite® devices in 176 (70%), 56 (22%), and 20 (8%) patients, respectively. With a median follow-up of 49 months, rates of Grade 1 (G1) and Grade 2-3 (G2-3) toxicity are:

 3D-CRTBrachytherapy   G1G2-3G1G2-3G1G2-3 N (%)N (%)N (%)N (%)  Fibrosis13 (46%)1 (4%)176 (72%)6 (2%)p=0.008p=0.54Fat Necrosis0 (0%)0 (0%)0 (0%)4 (2%)p=1.00p=1.00Telangiectasia6 (21%)1 (4%)44 (18%)5 (2%)p=0.61p=0.48Seroma2 (7%)1 (4%)135 (55%)12 (5%)p<0.0001p=1.00

Mean skin dose of the maximally-irradiated 0.1 cc (D0.1cc) of skin was significantly higher in patients who developed telangiectasia (103.4% ± 16.1% compared to 96.5% ± 18.6% of prescription dose, p=0.007) and fibrosis (100.1% ± 15.5% compared to 92.8% ± 23.0% of prescription dose, p=0.02). Crude rates of fair or poor cosmetic outcome at 2-4 and 4-6 years were 6.9% and 14.8%, respectively, for 3D-CRT and 14.8% and 21.3%, respectively, for brachytherapy (p>0.05 at both timepoints). Five-year recurrence-free survival was 96.3% with 3D-CRT and 96.1% for brachytherapy (p>0.05).

Conclusion:

APBI with single-entry multi-lumen intracavitary brachytherapy is associated with increased rates of grade 1 fibrosis and seroma than APBI with 3D-CRT. Higher mean skin D0.1cc is associated with increased risk of telangiectasia and fibrosis. Despite increased low-grade fibrosis, there is no significant difference in radiation oncologist-reported fair or poor cosmetic outcome out to six years, or rate of five-year ipsilateral breast recurrence.

Citation Format: Stecklein SR, Babiera GV, Bedrosian I, Shaitelman SF, Ballo MT, Tereffe W, Arzu IY, Perkins GH, Strom EA, Reed VK, Dvorak T, Smith BD, Woodward WA, Hoffman KE, Schlembach PJ, Chronowski GM, Shah SJ, Kirsner SM, Nelson CL, Guerra W, Dibaj SS, Bloom ES. Prospective comparison of late toxicity and cosmetic outcome after accelerated partial breast irradiation with conformal external beam radiotherapy or single-entry multi-lumen intracavitary brachytherapy [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P2-11-12.

Characteristics and outcome of patients with therapy-related acute promyelocytic leukemia front-line treated with or without arsenic trioxide

Therapy-related acute promyelocytic leukemia (t-APL) is relatively rare, with limited data on outcome after treatment with arsenic trioxide (ATO) compared to standard intensive chemotherapy (CTX). We evaluated 103 adult t-APL patients undergoing treatment with all-trans retinoic acid (ATRA) alone (n=7) or in combination with ATO (n=24), CTX (n=53), or both (n=19). Complete remissions were achieved after induction therapy in 57% with ATRA, 100% with ATO/ATRA, 78% with CTX/ATRA, and 95% with CTX/ATO/ATRA. Early death rates were 43% for ATRA, 0% for ATO/ATRA, 12% for CTX/ATRA and 5% for CTX/ATO/ATRA. Three patients relapsed, two developed therapy-related acute myeloid leukemia and 13 died in remission including seven patients with recurrence of the prior malignancy. Median follow-up for survival was 3.7 years. None of the patients treated with ATRA alone survived beyond one year. Event-free survival was significantly higher after ATO-based therapy (95%, 95% CI, 82-99%) as compared to CTX/ATRA (78%, 95% CI, 64-87%; P=0.042), if deaths due to recurrence of the prior malignancy were censored. The estimated 2-year overall survival in intensively treated patients was 88% (95% CI, 80-93%) without difference according to treatment (P=0.47). ATO when added to ATRA or CTX/ATRA is feasible and leads to better outcomes as compared to CTX/ATRA in t-APL.

Abstract ES6-3: ES6-3 Radiation implications post neoadjuvant therapy

Neoadjuvant therapy offers unique challenges and opportunities for the radiation oncologist. Classical indications for radiation have been rooted in the pathologic analysis of tissue resected prior to treating the patient with systemic therapy. However, in patients treated with neoadjuvant therapy, pathologic findings are frequently altered by the administration of systemic therapy, and thus classical indications for radiation may be clouded. Nevertheless, the degree of response to neoadjuvant therapy offers a novel prognostic factor which reflects intrinsic tumor biology and affords the opportunity for a new, precision approach to risk stratification and radiation therapy treatment decision making.

To maximally capitalize on the information gained from treating a patient with neoadjuvant chemotherapy, patients must be meticulously staged, preferably by a multidisciplinary team, prior to initiation of systemic therapy. Ultrasound of the regional nodal basins including the low axillary, infraclavicular, supraclavicular, and internal mammary nodal chains with ultrasound-guided fine needle aspiration of radiographically abnormal nodes enables detailed mapping of the local-regional disease extent. Cross-sectional imaging with CT and/or PET/CT is also helpful to permit customized radiation field design after systemic therapy and surgery. These imaging studies are invaluable to the radiation oncologist and allow for optimal field design to facilitate cure. Additionally, nodal surgery prior to administration of systemic therapy, while helpful in documenting pre-treatment nodal status, results in loss of ability to accurately assess response to chemotherapy in the lymph nodes and is thus avoided in our practice.

The available evidence indicates that patients experiencing a pathologic complete response have exceptional local-regional control. Accordingly, current randomized trials are exploring whether either radiation or surgery can be de-escalated within this context. In contrast, for patients with significant residual tumor burden following neoadjuvant chemotherapy, local-regional control outcomes are suboptimal for those with triple negative or HER2 positive disease. Novel strategies to escalate therapy with radiosensitizers or other biologic agents are needed for this population.

Citation Format: Smith BD. ES6-3 Radiation implications post neoadjuvant therapy [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr ES6-3.

Abstract P4-20-05: Patient-reported cosmetic outcomes in older breast cancer survivors: A population-based survey study

Background: For older women with breast cancer, local therapy options may include (1) lumpectomy followed by whole breast irradiation (Lump+WBI), (2) lumpectomy followed by brachytherapy (Lump+Brachy), (3) lumpectomy followed by endocrine therapy alone without radiation (Lump alone), (4) mastectomy without radiation (Mast alone), or (5) mastectomy followed by radiation (Mast+RT). For many patients, several of these options are acceptable based on current guidelines, but little is known about the impact of treatment choice on long-term cosmetic outcomes. We surveyed a population-based cohort of older breast cancer survivors treated with 1 of these 5 options to assess patient satisfaction with cosmetic outcome.

Methods: We used nationally comprehensive Medicare claims to identify women age ≥67 diagnosed with non-metastatic breast cancer in 2009, treated with 1 of these 5 treatment options, and still alive in 2015. From this cohort, 1650 patients (330 patients per local therapy) were randomly selected. Of these, 397 opted out, and the remaining 1253 potential participants were mailed a survey that included the CanSORT Satisfaction with Breast Cosmetic Outcomes instrument (5-point scale, higher score indicates greater satisfaction) and the Breast-Q Satisfaction with Breast instrument (0-100 Rasch transformed score, higher score indicates greater satisfaction). Multivariable linear regression models were used to assess the association of local therapy with each outcome, adjusting for age, race, comorbidity, chemotherapy, patient-reported BMI, bra cup size, smoking, income, and education. Spearman's correlation assessed the relationship between the 2 outcomes. All analyses incorporated sample and response weights.

Results: We received completed surveys from 498 women (30% response rate). The median age was 73 years (range, 67-87 years). The interval from diagnosis to survey was 6 years for all patients. Among patients with evaluable CanSORT responses (n=439), the weighted mean score by treatment group was 3.64 for Lump+WBI, 4.01 for Lump+Brachy, 3.83 for Lump alone, 3.28 for Mast alone, and 3.25 for Mast+RT. In multivariable analysis with Lump+WBI as the referent, the adjusted CanSORT mean score was 0.37 points higher for Lump+Brachy (P=0.009), 0.35 points lower for Mast alone (P=0.035), and 0.33 points lower for Mast+RT (P=0.048). Among patients with evaluable Breast-Q Satisfaction responses (n=418), the weighted mean score by treatment group was 60.9 for Lump+WBI, 68.8 for Lump+Brachy, 66.7 for Lump alone, 58.8 for Mast alone, and 52.0 for Mast+RT. In multivariable analysis with Lump+WBI as the referent, the adjusted Breast-Q Satisfaction score was 7.4 points higher for Lump+Brachy (P=0.03) and 7.8 points lower for Mast+RT (P=0.04). Higher comorbidity predicted worse cosmetic outcome in both models; no other variables were associated with both outcomes. The 2 outcomes were highly correlated (Spearman's coefficient=0.8, P<0.0001).

Conclusion: In this nationally representative cohort, satisfaction with cosmetic outcome (as measured by 2 distinct instruments) was higher for patients treated with Lump+Brachy and lower for those treated with Mast+RT compared to Lump+WBI. These results may be used to inform patient treatment decisions.

Citation Format: Swanick CW, Lei X, Xu Y, Shen Y, Goodwin NA, Giordano SH, Hunt KK, Jagsi R, Shaitelman S, Peterson SK, Smith BD. Patient-reported cosmetic outcomes in older breast cancer survivors: A population-based survey study [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-20-05.

Abstract S3-07: Complication and economic burden of local therapy options for early breast cancer

Background: Guideline-concordant local therapy options for early breast cancer include lumpectomy plus whole breast irradiation (lump+WBI), lumpectomy plus brachytherapy (lump+brachy), mastectomy without reconstruction or radiation (mast alone), mastectomy with reconstruction without radiation (mast+recon), and, in older women, lumpectomy without radiation (lump alone). Little is known regarding the comparative complication and economic burden of these options in the general population.

Methods: We used the MarketScan database which includes younger women with private insurance and the SEER-Medicare database which includes older women with Medicare. Women were included if they had early stage disease (T1/2 N0/1 M0) diagnosed in 2000-2011, no prior cancer, and complete insurance coverage from 12 months prior through 24 months after diagnosis. A complication from local therapy was defined as a diagnosis or procedure code for any of the following within 24 months of diagnosis: wound complication, local infection, seroma/hematoma, fat necrosis, breast pain, pneumonitis, rib fracture, and implant removal. Total costs and complication-related costs within 24 months of diagnosis were calculated from a payer's perspective and are reported in 2014 dollars. Logistic regression compared complications by local therapy and generalized linear regression (log link function, gamma distribution) compared complication-related and total costs by local therapy; all models adjusted for relevant covariables.

Results: We selected 44,344 patients from the MarketScan cohort, median age of 53, and 50,562 patients from the SEER-Medicare cohort, median age of 75. For the MarketScan cohort, risk of complications varied as follows: 29% risk in patients treated with lump+WBI (referent), 44% with lump+brachy (adjusted odds ratio [AOR]=2.00;P<.001), 25% with mast alone (AOR=0.85;P<.001), and 54% with mast+recon (AOR=2.89;P<.001). For the SEER-Medicare cohort, risk of complications varied as follows: 37% with lump+WBI (referent), 52% with lump+brachy (AOR=1.91;P<.001), 37% with mast alone (AOR=0.97;P=.17), 65% with mast+recon (AOR=3.17; P<.001), and 30% with lump alone (AOR=0.81; P<.001). Compared to lump+WBI, mean adjusted complication-related cost was $8,085 higher per patient with mast+recon in the MarketScan cohort and $3,711 higher per patient with mast+recon in the SEER-Medicare cohort. In contrast, complication-related costs were similar (+/- $750) for all other local therapy options relative to lump+WBI in both cohorts. For total cost, mast+recon was the most expensive local therapy in the MarketScan cohort, with mean adjusted total cost of $77,321, which was $15,181 more expensive than lump+WBI. In the SEER-Medicare cohort, lump+brachy was the most expensive option ($39,534), followed by mast+recon ($35,269), lump+WBI ($32,562), mast alone ($26,401), and lump alone ($24,455).

Conclusion: Mast+recon results in the highest complication rate and complication-related cost in both younger women and older women with early breast cancer. These findings are relevant to defining which local therapies offer the highest value to patients, payers, and society, and are relevant to patients when evaluating their local therapy options.

Citation Format: Smith BD, Jiang J, Shih Y-CT, Giordano SH, Huo J, Jagsi R, Caudle AS, Hunt KK, Shaitelman SF, Buchholz TA, Shirvani SM. Complication and economic burden of local therapy options for early breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr S3-07.

Abstract P5-08-04: Bioscore: A novel staging system for breast cancer patients receiving neoadjuvant chemotherapy

Background: We previously described a novel breast cancer staging system, the CPS+EG score, which incorporates pretreatment clinical stage, post-treatment pathologic stage, estrogen receptor (ER) status and nuclear grade to create an ordinal scale that is predictive of disease-specific survival (DSS) after receipt of neoadjuvant chemotherapy. The prior work predated (1997-2005) routine use of trastuzumab for patients with HER2+ disease. The current study was undertaken to update the staging system with a more contemporary cohort of patients to include patients with HER2+ disease receiving trastuzumab. The impact of using 1% as the cutoff for ER-positivity was also assessed.

Methods: A cohort of 2377 patients treated with neoadjuvant chemotherapy from 2005-2012 was identified. Clinicopathologic characteristics, treatment regimens and patient outcomes were recorded. Patient scores were computed using two versions of the CPS+EG staging system with ER status categorized as positive if >10% or if >1%. Fits of the Cox proportional hazards (PH) model for the two sets of prognostic scores were compared using the Akaike Information Criterion (AIC). HER2 status was then added to the model and the likelihood ratio test was used to determine the improvement in fit.

Results: Median follow-up time was 4.2 years (range, 0.5 to 11.7). Five year DSS was 89% (95% CI: 87%-90%). This cohort validated our previous finding that the CPS+EG score facilitates more refined categorization into prognostic subgroups than initial clinical or final pathologic stage alone (table). The AIC demonstrated that the CPS+EG model fits were nearly identical for ER status categorized using either cutoff, though the fit was slightly better for the >1% cutoff. There were 591 HER2+ patients included; all of them received trastuzumab-based chemotherapy. The improvement in the fit of the model when HER2 status was added was highly significant (p=0.00005) and incorporation of HER2 into the CPS+EG staging system by adding one additional point for HER2-negative status defined the bioscore (table) which again stratified patients with respect to prognosis.

Conclusion: The current study demonstrates a novel bioscore that significantly improves a previously validated prognostic score in patients receiving neoadjuvant chemotherapy and allows the staging system to be applied to patients with HER2+ disease. We recommend that biologic markers and response to treatment be incorporated into the forthcoming revision of the AJCC staging system.

Clinical Stage5-yr DSS (95%CI)Pathologic Stage5-yr DSS (95%CI)CPS+EG Score (1% cutoff for ER+)5-yr DSS (95%CI)Bioscore5-yr DSS (95%CI)0 097% (95-98%)098% (92-100%)097% (78-10)%)IA96% (75-99%)IA95% (92-97%)198% (96-99%)199% (95-100%)IIA96% (94-97%)IB90% (76-98%)294% (91-95%)297% (95-98%)IIB90% (87-92%)IIA91% (87-94%)387% (84-90%)393% (90-95%)IIIA85% (80-89%)IIB86% (81-90%)475% (69-80%)486% (82-89%)IIIB78% (70-85%)IIIA80% (75-84%)552% (40-63%)571% (64-77%)IIIC76% (70-81%)IIIB64% (42-80%)60648% (35-60%) IIIC64% (55-72%)   70

Citation Format: Mittendorf EA, Vila J, Tucker SL, Chavez-MacGregor M, Smith BD, Symmans WF, Sahin AA, Hortobagyi GN, Hunt KK. Bioscore: A novel staging system for breast cancer patients receiving neoadjuvant chemotherapy. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-08-04.

MLN4924 induces Noxa upregulation in acute myelogenous leukemia and synergizes with Bcl-2 inhibitors

MLN4924 (pevonedistat), an inhibitor of the Nedd8 activating enzyme (NAE), has exhibited promising clinical activity in acute myelogenous leukemia (AML). Here we demonstrate that MLN4924 induces apoptosis in AML cell lines and clinical samples via a mechanism distinct from those observed in other malignancies. Inactivation of E3 cullin ring ligases (CRLs) through NAE inhibition causes accumulation of the CRL substrate c-Myc, which transactivates the PMAIP1 gene encoding Noxa, leading to increased Noxa protein, Bax and Bak activation, and subsequent apoptotic changes. Importantly, c-Myc knockdown diminishes Noxa induction; and Noxa siRNA diminishes MLN4924-induced killing. Because Noxa also neutralizes Mcl-1, an anti-apoptotic Bcl-2 paralog often upregulated in resistant AML, further experiments have examined the effect of combining MLN4924 with BH3 mimetics that target other anti-apoptotic proteins. In combination with ABT-199 or ABT-263 (navitoclax), MLN4924 exerts a synergistic cytotoxic effect. Collectively, these results provide new insight into MLN4924-induced engagement of the apoptotic machinery that could help guide further exploration of MLN4924 for AML.

Toxicity and the fractional distribution of trace metals accumulated from contaminated sediments by the clam Scrobicularia plana exposed in the laboratory and the field

The relationship between the subcellular distribution of accumulated toxic metals into five operational fractions (subsequently combined into presumed detoxified and non-detoxified components) and toxicity in the clam Scrobicularia plana was investigated under different laboratory exposures. Clams were exposed to metal contaminated media (water and diet) and analysed for the partitioning of accumulated As, Cu and Zn into subcellular fractions. In general, metallothionein-like proteins, metal-rich granules and cellular debris in different proportions acted as main storage sites of accumulated metals in the clam soft tissues for these three metals. No significant differences were noted in the accumulation rates of As, Cu and Zn of groups of individuals with or without apparent signs of toxicity after up to 30 days of exposure to naturally contaminated sediment mixtures. There was, however, an increased proportional accumulation of Cu in the non-detoxified fraction with increased Cu accumulation rate in the clams, suggesting that the Cu uptake rate from contaminated sediments exceeded the combined rates of elimination and detoxification of Cu, with the subsequent likelihood for toxic effects in the clams.

Serine protease inhibitor-6 differentially affects the survival of effector and memory alloreactive CD8-T cells

The clonal expansion of effector T cells and subsequent generation of memory T cells are critical in determining the outcome of transplantation. While cytotoxic T lymphocytes induce direct cytolysis of target cells through secretion of Granzyme-B (GrB), they also express cytoplasmic serine protease inhibitor-6 (Spi6) to protect themselves from GrB that has leaked from granules. Here, we studied the role of GrB/Spi6 axis in determining clonal expansion of alloreactive CD8-T cells and subsequent generation of memory CD8-T cells in transplantation. CD8-T cells from Spi6(-/-) mice underwent more GrB mediated apoptosis upon alloantigen stimulation in vitro and in vivo following adoptive transfer into an allogeneic host. Interestingly, while OT1.Spi6(-/-) CD8 T cells showed significantly lower clonal expansion following skin transplants from OVA mice, there was no difference in the size of the effector memory CD8-T cells long after transplantation. Furthermore, lack of Spi6 resulted in a decrease of short-lived-effector-CD8-cells but did not impact the pool of memory-precursor-effector-CD8-cells. Similar results were found in heart transplant models. Our findings suggest that the final alloreactive CD8-memory-pool-size is independent from the initial clonal-proliferation as memory precursors express low levels of GrB and therefore are independent of Spi6 for survival. These data advance our understanding of memory T cells generation in transplantation and provide basis for Spi6 based strategies to target effector T cells.

Biomonitoring of trace metal bioavailabilities to the barnacle Amphibalanus amphitrite along the Iranian coast of the Persian Gulf

The fouling barnacle Amphibalanus amphitrite is a cosmopolitan biomonitor of trace metal bioavailabilities, with an international comparative data set of body metal concentrations. Bioavailabilities of As, Cd, Cr, Cu, Fe, Mn, Pb, V and Zn to A. amphitrite were investigated at 19 sites along the Iranian coast of the understudied Persian Gulf. Commercial and fishing ports showed extremely high Cu bioavailabilities, associated with high Zn bioavailabilities, possibly from antifouling paints and procedures. V availability was raised at one port, perhaps associated with fuel leakage. Cd bioavailabilities were raised at sites near the Strait of Hormuz, perhaps affected by adjacent upwelling off Oman. The As data allow a reinterpretation of the typical range of accumulated As concentrations in A. amphitrite. The Persian Gulf data add a new region to the A. amphitrite database, confirming its importance in assessing the ecotoxicologically significant trace metal contamination of coastal waters across the world.

Biodynamic modelling of the bioaccumulation of trace metals (Ag, As and Zn) by an infaunal estuarine invertebrate, the clam Scrobicularia plana

Biodynamic modelling was used to investigate the uptake and accumulation of three trace metals (Ag, As, Zn) by the deposit feeding estuarine bivalve mollusc Scrobicularia plana. Radioactive labelling techniques were used to quantify the rates of trace metal uptake (and subsequent elimination) from water and sediment diet. The uptake rate constant from solution (±SE) was greatest for Ag (3.954±0.375 l g(-1) d(-1)) followed by As (0.807±0.129 l g(-1) d(-1)) and Zn (0.103±0.016 l g(-1) d(-1)). Assimilation efficiencies from ingested sediment were 40.2±1.3% (Ag), 31.7±1.0% (Zn) and 25.3±0.9% (As). Efflux rate constants after exposure to metals in the solution or sediment fell in the range of 0.014-0.060 d(-1). By incorporating these physiological parameters into biodynamic models, our results showed that dissolved metal is the predominant source of accumulated Ag, As and Zn in S. plana, accounting for 66-99%, 50-97% and 52-98% of total accumulation of Ag, As and Zn, respectively, under different field exposure conditions. In general, model-predicted steady state concentrations of Ag, As and Zn matched well with those observed in clams collected in SW England estuaries. Our findings highlight the potential of biodynamic modelling to predict Ag, As and Zn accumulation in S. plana, taking into account specific dissolved and sediment concentrations of the metals at a particular field site, together with local water and sediment geochemistries.

DNMT3A and IDH mutations in acute myeloid leukemia and other myeloid malignancies: associations with prognosis and potential treatment strategies

The development of effective treatment strategies for most forms of acute myeloid leukemia (AML) has languished for the past several decades. There are a number of reasons for this, but key among them is the considerable heterogeneity of this disease and the paucity of molecular markers that can be used to predict clinical outcomes and responsiveness to different therapies. The recent large-scale sequencing of AML genomes is now providing opportunities for patient stratification and personalized approaches to treatment that are based on individual mutational profiles. It is particularly notable that studies by The Cancer Genome Atlas and others have determined that 44% of patients with AML exhibit mutations in genes that regulate methylation of genomic DNA. In particular, frequent mutation has been observed in the genes encoding DNA methyltransferase 3A (DNMT3A), isocitrate dehydrogenase 1 (IDH1) and isocitrate dehydrogenase 2 (IDH2), as well as Tet oncogene family member 2. This review will summarize the incidence of these mutations, their impact on biochemical functions including epigenetic modification of genomic DNA and their potential usefulness as prognostic indicators. Importantly, the presence of DNMT3A, IDH1 or IDH2 mutations may confer sensitivity to novel therapeutic approaches, including the use of demethylating agents. Therefore, the clinical experience with decitabine and azacitidine in the treatment of patients harboring these mutations will be reviewed. Overall, we propose that understanding the role of these mutations in AML biology will lead to more rational therapeutic approaches targeting molecularly defined subtypes of the disease.

Abstract P4-15-12: Rebastinib in combination with eribulin ablates TIE2-expressing macrophages, reduces metastasis, and increases survival in the PyMT metastatic breast cancer model

In cancer models, TIE2 kinase plays an important role in angiogenesis, vasculogenesis, and tumor metastasis. TIE2 expression is largely restricted to vascular endothelial cells, tissue macrophages, and bone marrow derived TIE2-expressing monocytes (TEMs), which are proangiogenic, provasculogenic and enhance invasiveness. The hypoxic tumor environment engendered by damaging the vasculature with chemotherapy, radiation, or anti-angiogenic treatments leads to rebound tumor vascularization by an angiogenic switch from the VEGF pathway to the angiopoietin/TIE2 pathway. This leads to recruitment of provasculogenic TEMs from the bone marrow, leading to the growth of residual tumor cells and disease progression. Significantly, a subset of TIE2-expressing macrophages are located within specialized vascular structures known as tumor microenvironment for metastases (TMEMs). Recent observations have linked TIE2-expressing macrophages within TMEM structures to intravasation of cancer cells into circulation and subsequent dissemination to metastatic sites. We hypothesized that TIE2 inhibition should decrease migration and association of TEMs with blood vessels in the tumor stroma, therefore blocking their proangiogenic activity and leading to reduced tumor growth. TIE2 inhibition may also alter TMEM function, leading directly to a blockade of metastasis.

Rebastinib is a picomolar inhibitor of TIE2 kinase, and exhibits an extraordinarily long off-rate from TIE2, measured to be over 24 hours in a cell-based assay. Herein, we examine the efficacy of rebastinib in the polyoma middle-T antigen (PyMT) syngeneic mouse breast cancer model. In this model, PyMT breast cancer cells are implanted in the mammary fat pad, and primary tumor growth leads to metastasis, which is known to be modulated by TEMs and TMEM vascular structures. We examined dosing rebastinib in combination with eribulin, an inhibitor of microtubule dynamics that recently was FDA-approved for treatment-refractory metastatic breast cancer. Rebastinib treatment in this model significantly ablated TEMs in the primary tumor stroma and caused a significant decrease in lung metastases. Furthermore, the combination of rebastinib and eribulin led to a significant further decrease in lung metastases compared to treatment with eribulin alone (Table 1). Rebastinib also enhanced the activity of eribulin in reducing primary tumor growth and regrowth of tumor post-resection.

TIE2 inhibition represents a novel treatment approach for metastatic breast cancer and other cancers that rely on TEMs and TMEMs for growth and metastasis. As such, rebastinib has been selected for further clinical development in combination with eribulin for treatment-refractory metastatic breast cancer, with a Phase 1b trial being planned for late 2013.

Rebastinib reduces lung metastases in the PyMT breast cancer modelTreatmentLung Metastases (% of Control)Vehicle100%Eribulin 1 mg/kg three times/week71%Rebastinib 10 mg/kg twice/week + Eribulin 1 mg/kg23%Eribulin 0.3 mg/kg three times/week71%Rebastinib 10 mg/kg twice/week + Eribulin 0.3 mg/kg51%Eribulin 0.1 mg/kg three times/week72%Rebastinib 10 mg/kg twice/week + Eribulin 0.1 mg/kg43%

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-15-12.

Abstract P5-14-08: Prospective phase II study of concurrent capecitabine and radiation demonstrates futility in triple negative chemo-resistant breast cancer

Background: Capecitabine is an established radiosensitizer in rectal and other cancers. We conducted a prospective single arm phase II study to examine the response rate of gross chemo-refractory breast cancer treated with concurrent capecitabine and radiotherapy.

Methods: Patients who had inoperable or marginally operable gross disease in the breast and/or lymph node(s) after chemotherapy or gross disease on the chest wall or in the regional lymphatics after mastectomy were eligible. Patients 1-9 received capecitabine 825 mg/m2 BID daily beginning on the first day of radiotherapy. Excess grade 3 toxicity (%) was observed; the protocol was amended and subsequent patients received drug only on radiation treatment days. Radiation dose was at the discretion of the treating physician (50Gy-72 Gy, with no more than 2.5 Gy/fraction). Response was assessed by a single physician using paired radiation planning CTs (pretreatment and on-treatment after 45 Gy). Clinical correlation to all other available imaging was also made. Kaplan-Meier curves were used to estimate overall survival (OS) and local recurrence-free survival (LRFS). Circulating tumor cells (CTCs) in blood were examined in consenting patients.

Results: The trial was stopped early after an unplanned interim analysis prompted by slow accrual suggested futility independent of response. From 2009-2012, 32 patients were accrued; 26 completed protocol specific treatment (17 post-mastectomy radiation with gross nodes, 4 pre-op, 5 aggressive palliation) and are included in this analysis. Median follow up was 7.3 months (interquartile range 6.7 – 17.4). Nineteen patients (73%) had a partial or complete response. Fourteen patients (53.9%) experienced at least one grade 3 non-dermatitis toxicity including 7/9 treated with continuous dosing. Four inoperable patients were treated with pre-op radiation therapy and 3 converted to operable. None achieved a pCR or near pCR. One-year actuarial OS was 52%. There was no difference in OS comparing among PMRT vs. preoperative or palliative RT (P = 0.90). One-year actuarial local recurrence free survival among PMRT patients was 38%. Ten patients had triple negative (TN) receptor status. There was no difference in radiation response by receptor status (P = 0.56); however, treatment was deemed subjectively futile (i.e., converted to operable but death secondary to new widespread M1 disease immediately post-op) in 9 of the 10 patients with TN disease versus 6 of the 16 patients with non-TN disease (P = 0.014). Median OS and 1-yr actuarial OS, among non-TN vs. TN patients were not reached vs. 6.1 months and 77% vs. 10% (P < 0.001), respectively. Eight/fifteen patients tested were positive for CTCs. CTCs did not correlate to receptor status, futility of RT or OS.

Conclusions: Capecitabine can be safely administered as a daily concurrent chemoradiation regimen with weekend holidays. However, in this small, prospective and selected cohort, concurrent chemoradiation with capecitabine was futile among patients with TN breast cancer. Alternative strategies are urgently needed in TN patients.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-14-08.

Abstract P4-15-13: Rebastinib in combination with paclitaxel ablates TIE2-expressing macrophages, reduces metastasis, and increases survival in the PyMT metastatic breast cancer model

In cancer models, TIE2 kinase plays an important role in angiogenesis, vasculogenesis, and tumor metastasis. TIE2 expression is largely restricted to vascular endothelial cells, tissue macrophages, and bone marrow derived TIE2-expressing monocytes (TEMs), which are proangiogenic, provasculogenic and enhance invasiveness. The hypoxic tumor environment engendered by damaging the vasculature with chemotherapy, radiation, or anti-angiogenic treatments leads to rebound tumor vascularization by an angiogenic switch from the VEGF pathway to the angiopoietin/TIE2 pathway. This leads to recruitment of provasculogenic TEMs from the bone marrow, leading to the growth of residual tumor cells and disease progression. Significantly, a subset of TIE2-expressing macrophages are located within specialized vascular structures known as tumor microenvironment for metastases (TMEMs). Recent observations have linked TIE2-expressing macrophages within TMEM structures to intravasation of cancer cells into circulation and subsequent dissemination to metastatic sites. We hypothesized that TIE2 inhibition should decrease migration and association of TEMs with blood vessels in the tumor stroma, therefore blocking their proangiogenic activity and leading to reduced tumor growth. TIE2 inhibition may also alter TMEM function, leading directly to a blockade of metastasis.

Rebastinib is a picomolar inhibitor of TIE2 kinase, and exhibits an extraordinarily long off-rate from TIE2, measured to be over 24 hours in a cell-based assay. Herein, we examine the efficacy of rebastinib in the polyoma middle-T antigen (PyMT) syngeneic mouse breast cancer model. In this model, PyMT breast cancer cells are implanted in the mammary fat pad, and primary tumor growth leads to metastasis, which is known to be modulated by TEMs and TMEM vascular structures. We examined multiple dosing schedules of rebastinib in combination with paclitaxel. Rebastinib treatment in this model significantly ablated TEMs in the primary tumor stroma and caused a significant decrease in lung metastases (Table 1). Furthermore, the combination of rebastinib and paclitaxel led to a significant further decrease in lung metastases compared to treatment with paclitaxel or rebastinib alone. Rebastinib also enhanced the activity of paclitaxel in reducing primary tumor growth and regrowth of tumor post-resection.

TIE2 inhibition with targeted therapy represents a novel treatment approach for metastatic breast cancer and other cancers that rely on TEMs and TMEMs for growth and metastasis. As such, rebastinib has been selected for further clinical development for treatment-refractory metastatic breast cancer, with a Phase 1b trial being planned for late 2013.

Rebastinib reduces lung metastases in the PyMT breast cancer modelStudynTreatmentLung Metastases (% of Control)110Vehicle100%110Paclitaxel 10 mg/kg Q5D36%110Rebastinib 10 mg/kg BID28%110Rebastinib 10 mg/kg BID + Paclitaxel7%210Vehicle100%210Paclitaxel 10 mg/kg Q5D51%210Rebastinib 10 mg/kg QD + Paclitaxel21%33Vehicle100%33Paclitaxel 10 mg/kg Q5D58%33Rebastinib 10 mg/kg twice/week + Paclitaxel28%

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-15-13.

Abstract S2-3: Disparities in the utilization of axillary sentinel lymph node biopsy among black and white patients with node-negative breast cancer from 2002–2007

Background: Disparities exist in many aspects of standard breast cancer treatment in certain patient populations. In the mid-1990s, axillary sentinel lymph node biopsy (SLNB) was introduced as an alternative to axillary lymph node dissection (ALND) for staging clinically node-negative breast cancer. During the early 2000s, the validity of SLNB was being determined and its technique was being disseminated throughout the surgical community. By the mid to late-2000s, SLNB had been shown to provide accurate axillary staging with lower complications and no difference in survival compared to ALND in node-negative patients. SLNB has now replaced ALND as the accepted method for staging early breast cancer. The purpose of this study is to examine differences in the utilization of SLNB in pathologic node-negative invasive black breast cancer patients compared to white patients as SLNB became standard axillary staging and whether this difference impacted patient complications.

Methods: Using the population-based Surveillance, Epidemiology, and End Results (SEER)-Medicare data, cases of incident, non-metastatic, pathologic node-negative breast cancer in women age≥66 were identified. Patients were considered to have undergone SLNB if specified by SEER records or if a billing claim for axillary lymphatic mapping was identified. Unadjusted associations of SLNB with race were evaluated using the chi-square test. The Cochran-Armitage test evaluated trends over time. Multivariate logistic regression tested whether race was associated with the use of SLNB after adjustment for clinicopathologic factors. Five-year cumulative incidence of lymphedema assessed via ICD-9 diagnosis codes was measured using the Kaplan-Meier method. Adjusted proportional hazards regression evaluated assiciations of race and ALND with lymphedema risk.

Results: Of 31,274 women identified, 1,767 (5.7%) were Black, 27,856 (89%) were White and 1,651 (5.3%) were of other/unknown race. SLNB was performed in 74% of white patients compared to 62% of black patients (P<0.001). Although use of SLNB increased by year for both black and white patients (P<0.001), a fixed disparity in the use of SLNB persisted through 2007.

Field-based performance of three pre-market rapid hepatitis C virus antibody assays in STAHR (Study to Assess Hepatitis C Risk) among young adults who inject drugs in San Diego, CA

BACKGROUND

Approximately 4.1 million Americans are estimated to have been infected with hepatitis C virus (HCV), 45-85% of whom are unaware of their infection. Persons who inject drugs (PWID) account for 55.8% of all persons with HCV antibody (anti-HCV) in the U.S. PWID have limited access to healthcare and are infrequently tested for anti-HCV using conventional laboratory assays.

OBJECTIVE

To evaluate performance characteristics (sensitivity and specificity) of three, pre-market rapid point-of-care tests (one oral fluid and two finger-stick assays) from two manufacturers (Chembio and MedMira) in settings providing services to young adult PWID in San Diego, CA.

STUDY DESIGN

Behavioral risk assessment surveys and testing for HCV were conducted among persons who reported injection drug use (IDU) within the past 6 months as part of the Study to Assess Hepatitis C Risk (STAHR) among PWID aged 18-40 years in 2009-2010. Sensitivity and specificity of the rapid anti-HCV assays were evaluated among STAHR participants, using two commonly used testing algorithms.

RESULTS

Variability in sensitivity (76.6-97.1%) and specificity (99.0-100.0%) was found across assays. The highest sensitivity achieved for the Chembio finger-stick blood, Chembio oral fluid and MedMira finger-stick blood tests was 97.1%, 85.4% and 80.0% respectively; the highest specificity was 99.0%, 100.0% and 100.0%, respectively. In multivariate analysis false negative anti-HCV results were associated with female sex for the MedMira blood assay.

CONCLUSIONS

Sensitive anti-HCV rapid assays are appropriate and feasible for high-prevalence, high-risk populations such as young PWID.

Arsenic toxicity in a sediment-dwelling polychaete: detoxification and arsenic metabolism

The accumulation, subcellular distribution and speciation of arsenic in the polychaete Arenicola marina were investigated under different laboratory exposure conditions representing a range of metal bioavailabilities, to gain an insight into the physiological mechanisms of how A. marina handles bioaccumulated arsenic and to improve our understanding of the potential ecotoxicological significance of bioaccumulated arsenic in this deposit-feeder. The exposure conditions included exposure to sublethal concentrations of dissolved arsenate, exposure to sublethal concentrations of sediment-bound metal mining mixtures, and exposure to lethal concentrations of sediment-bound metal mining mixtures and arsenic- and multiple metal-spiked sediments. The sub-lethal exposures indicate that arsenic bioaccumulated by the deposit-feeding polychaete A. marina is stored in the cytosol as heat stable proteins (~50%) including metallothioneins, possibly as As (III)-thiol complexes. The remaining arsenic is mainly accumulated in the fraction containing cellular debris (~20%), with decreasing proportions accumulated in the metal-rich granules, organelles and heat-sensitive proteins fractions. A biological detoxified metal compartment including heat stable proteins and the fraction containing metal-rich granules is capable of binding arsenic coming into the cells at a constant rate under sublethal arsenic bioavailabilities. The remaining arsenic entering the cell is bound loosely into the cellular debris fraction, which can be subsequently released and diverted to an expanding detoxified pool. Our results suggest that a metal sensitive compartment comprising the cellular debris, enzymes and organelles fractions may be more representative of the toxic effects observed.

"Bridge population": sex workers or their clients?--STI prevalence and risk behaviors of clients of female sex workers in China

As the HIV/AIDS epidemic and the spread of sexually transmitted infections (STIs) in China has come to the forefront of public health attention, female sex workers (FSWs) and their clients (CFSWs) are becoming increasingly important to HIV/STI prevention efforts. This secondary analysis uses data abstracted from the Chinese Health and Family Life Survey 1999-2000 to report prevalence rates of two STIs as well as sexual risk behaviors for CFSWs - men who paid for sex with FSWs in the past 12 months - in comparison with men who had not patronized FSWs. Among 1879 Chinese CFSWs who completed anonymous interviews and urine testing, 152 (6.3%, weighted) said they had paid for sex in the past 12 months and 18.8% of CFSWs (weighted) tested positive for gonorrhea. CFSWs were 10 times more likely to have an STI (either self-reported or tested) than non-client Chinese men, and they were equally likely to use condoms inconsistently with their spouses. This study highlights the importance of studying CFSWs who use condoms inconsistently and do not practice safe sex with their spouse as a potential bridge population. Prevention and intervention efforts should target this bridge population and include education on HIV/AIDS and STI transmission, condom promotion, marriage counseling, destigmatization of HIV and STIs, and promotion of STI diagnosis and treatment.

Have the bioavailabilities of trace metals to a suite of biomonitors changed over three decades in SW England estuaries historically affected by mining?

Many estuaries of southwest England were heavily contaminated with toxic metals associated with the mining of copper and other metals, particularly between 1850 and 1900. The question remains whether the passage of time has brought remediation to these estuaries. In 2003 and 2006 we revisited sites in 5 metal-contaminated estuaries sampled in the 1970s and 1980s - Restronguet Creek, Gannel, West Looe, East Looe and Tavy. We evaluate changes in metal contamination in sediments and in metal bioavailabilities in sediments and water to local organisms employed as biomonitors. We find that the decline in contamination in these estuaries is complex. Differences in bioavailable contamination in the water column were detectable, as were significant detectable changes in at least some estuaries in bioavailable metal contamination originating from sediments. However, in the 100 years since mining activities declined, bioavailable contamination has not declined to the regional baseline in any estuary affected by the mine wastes. The greatest decline in contamination occurred in the one instance (East Looe) where a previous industrial source of (Ag) contamination was considered. We used the macroalgae Fucus vesiculosus and Ascophyllum nodosum as biomonitors of dissolved metal bioavailabilities and the deposit feeders Nereis diversicolor and Scrobicularia plana as biomonitors of bioavailable metal in sediments. We found no systematic decrease in the atypically high Ag, Cu, Pb and Zn concentrations in the estuarine sediments over a 26 year period. Accumulated metal (Ag, As, Cu, Pb, and Zn) concentrations in the deposit feeders are similarly still atypically high in at least one estuary for each metal, and there is no consistent evidence for general decreases in sediment metal bioavailabilities over time. We conclude that the legacy of mining in sheltered estuaries of southwest England is the ongoing presence of sediments rich in metals bioavailable to deposit feeders, while dissolved metal bioavailabilities from this historical source alone are no longer atypically high.

Abstract P4-11-15: Outcomes for Breast Cancer Patients with Isolated Metastasis or Recurrence to the Contralateral Nodal Basins

Background: Aggressive treatment of isolated breast cancer metastasis to either bone or lung has been reported to achieve long term survival. For the first time, we analyzed outcomes for patients (pts) with isolated metastasis to the contralateral (contra) supraclavicular (SCV) and/or axillary nodal basins.

Material and Methods: Pts treated with definitive or palliative radiation to the contra nodal basin(s) at M.D. Anderson were analyzed from the period of 2005-2010. They were divided into two groups: pts initially diagnosed with contra SCV and/or axilla as the only site of metastasis (designated Primary), and pts with recurrence in the contra SCV and/or axilla, without other distant metastasis (designated Recurrent).

Results: Of 34 potential pts with contra lymph node metastasis, 13 had isolated disease and were analyzed. In the Primary group (N=8, T4d N1- 3c M1), median survival was 25 mos, and 2-yr actuarial overall survivalwas 62.5%. All received neoadjuvant anthracycline and/or taxane-based chemotherapy followed by ipsilateral (ipsi) modified radical mastectomy and ipsi axillary lymph node dissection (ALND). The contra lymphatics were treated with ALND followed by radiation (N=5, 56-60 Gy) or with radiation alone (N=3, 45-66 Gy). Radiation fields included ipsi chest wall as well as ipsi and involved contra lymphatics. The contra chest wall or breast was radiated in 3 of the 8 pts. Two pts had estrogen receptor (ER) positive disease, and all had Her2-neu negative disease. Both ER+ pts are alive with no evidence of disease (NED; 1 had contra ALND; survival 25 and 51 mos). All 6 ER-pts died with disease (WD; 4 had contra ALND; survival 10 to 32 mos). One pt had an in-field recurrence in the contra nodal basin (51 Gy post ALND). No contra chest wall/breast recurrences were seen. All ER-pts developed additional distant metastasis, most within 4 mos of starting adjuvant radiation.

Regarding the Recurrent group (N=5), median survival was 25 mos after recurrence. Two ER+ pts received initial anti-estrogen therapy; all ER-pts initially received a taxane-based chemotherapy. The contra chest wall or breast was radiated in addition to the involved contra lymphatics in 3 of the 5 pts. Two pts had adjuvant radiation treatment with definitive intent to the contra lymphatics after ALND (50-50.4 Gy), with 1 alive/NED (66 mos from recurrence, no radiation to the contra breast) and 1 dead/WD (25 mos from recurrence). Radiation intent was palliation in 3 pts (none received ALND) with 1 alive/WD (60 Gy, 64 mos from recurrence) and 2 dead/WD (53.8 and 45 Gy, 6 and 18 mos from recurrence, respectively). In-field recurrence in the contra nodal basin occurred in 1 pt (50.4 Gy). Pts who died had progressive disease or additional distant metastasis within 3 mos of starting radiation.

Discussion: In this uncommon clinical scenario, locoregional control of the contra lymphatics was achieved with radiation alone or with surgery followed by radiation for a select group of pts; control was achieved without radiating the contra chest wall/breast. Only ER+ pts were rendered NED. Most ER-pts quickly developed other distant metastasis, highlighting the need for more effective systemic therapy.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P4-11-15.

Abstract P1-17-02: Outcome after Locoregional Recurrence in Patients with Inflammatory Breast Cancer

Purpose: High rates of locoregional recurrence (LRR) have been reported in spite of comprehensive tri-modality therapy for patients with inflammatory breast cancer (IBC). The aim of this study was to examine the prognosis of patients who have experienced LRR after treated primary IBC. Methods:

We retrospectively reviewed information for 124 IBC patients who experienced a LRR seen in our institution from 1990-2008. 63 patients had simultaneous distant disease (DM) +/−3 months of LRR (simLRR),

5 patients had LRR > 3 months subsequent to DM, while 56 patients had isolated LRR >3 months prior to DM (isLRR). Overall survival (OS) was calculated from date of recurrence using the Kaplan-Meier method. Results:

Median time to LRR from diagnosis was 13 months (interquartile range 8-21 months). Median survival after LRR was 15 months. 2-yr OS was 46%. Regarding the primary tumors, 23% were estrogen receptor positive (ER+), 33% were HER2-neu positive (H2N+), 81% had lymph vascular space invasion (LVSI), and 83% were grade 3. Comparing isLRR and simLRR cohorts, median survival was 18 months vs. 10 months and 2 yr-OS was 66% vs. 28%, respectively. ER+ and H2N+ primary status predicted for longer 2 yr OS among patients with simLRR but not among isLRR patients. (simLRR, ER+ 57% vs. ER-19% p = 0.02, H2N+ 45% vs. H2N-17% p = 0.01; IsLRR ER+ vs. ER-92% vs. 55% p = 0.15, H2N+ 86% vs. H2N-57% p = 0.11). LVSI was not prognostic in either group and Grade 3 primary trended towards worse outcome among isLRR cohort only, Grade 2 83% vs. Grade 3 64% P = 0.08. Molecular subtyping using ER and H2N status to group tumors demonstrates basal subtype in the primary tumor compared to H2N, luminal B and luminal A is associated with significantly worse 2 yr OS after isLRR (43% vs. 88%, 82%, and 83%, P = 0.04) and simLRR (13% vs. 34%, 80%, 32% P = 0.005) respectively. Conclusions:

Forty-five% of LRR occurred as isolated first events. LRRs generally occur within 2 years after primary IBC treatment and are associated with poor outcomes even as first events. Basal subtype predicts for worse overall survival regardless of distant disease.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-17-02.

Urine catecholamine levels as diagnostic markers for neuroblastoma in a defined population: implications for ophthalmic practice

PURPOSE

although elevated urinary catecholamine levels have been reported in 90-95% of patients with neuroblastoma, more recent studies of pediatric Horner syndrome caused by an underling neuroblastoma have reported normal values at presentation. The purpose of this population-based study is to report the percentage of cases of neuroblastoma with elevated urinary catecholamine levels at presentation and to suggest a recommended work-up for cases of idiopathic pediatric Horner syndrome.

METHODS

the medical records of all pediatric (<19 years) residents of Olmsted County, Minnesota diagnosed with neuroblastoma from 1 January 1969 through 31 December 2008 were retrospectively reviewed.

RESULTS

a total of 14 patients <19 years of age were diagnosed with neuroblastoma as residents of Olmsted County, Minnesota, during the 40-year study period. A total of 10 (71%) of the 14 cases manifested elevated urinary catecholamine metabolites at the initial presentation. Urinary vanillylmandelic acid (VMA) levels were greater than twice the upper limit of normal in eight (57%) of 14 cases, whereas homovanillic acid (HVA) levels were greater than two times the upper limit of normal in 10 (71%) of the 14 cases. Three (75%) of the four cases without significantly elevated urinary VMA or HVA levels were diagnosed with stage IV disease, whereas one (25%) had stage II neuroblastoma.

CONCLUSION

urinary catecholamine levels were significantly elevated at presentation in 10 (71%) of the 14 neuroblastoma cases during the 40-year study period, suggesting that greater emphasis be placed on performing a thorough physical examination and obtaining warranted imaging studies in cases of idiopathic pediatric Horner syndrome.

Prevalence and risks for sexually transmitted infections among a national sample of migrants versus non-migrants in China

This study aims to describe and compare the gender-specific prevalence of chlamydia and gonorrhoea, sexual behaviours and experiences, and risk factors associated with sexually transmitted infections (STIs) among migrants versus rural and urban non-migrants in China. Data were abstracted from the Chinese Health and Family Life Survey conducted from 1999 to 2000, which provided a nationally representative adult (ages 20-64 years) sample. STI results were determined using a urine-based nucleic acid amplification assay. The prevalence of chlamydia for migrant women was triple that of rural non-migrant women. Migrants were more likely to engage in STI-associated risk behaviours than non-migrants (e.g. receiving money for sex). Among migrants, women were more likely than men to have STIs. The high STI prevalence among migrants highlights an urgent need to implement comprehensive prevention and intervention programmes targeting the cultural, social and structural needs of migrants in the city, especially migrant women.

Chenopodium as a prehistoric domesticate in eastern north america: evidence from russell cave, alabama

Approximately 50,000 carbonized fruits of the species Chenopodium berlandieri recovered from Russell Cave, Alabama, and dating to 1975 +/- 55 before the present, exhibit a set of interrelated morphological characteristics reflecting domestication (thin testa, truncate margin, rectanguloid fruit cross section, ligulate cotyledons, and increased internal fruit volume). These morphological characteristics establish the presence of a domestic variety of Chenopodium in the eastern United States by 2000 years ago.

Biodynamic modelling of the accumulation of Ag, Cd and Zn by the deposit-feeding polychaete Nereis diversicolor: inter-population variability and a generalised predictive model

Biodynamic parameters of the ragworm Nereis diversicolor from southern Spain and south England were experimentally derived to assess the inter-population variability of physiological parameters of the bioaccumulation of Ag, Cd and Zn from water and sediment. Although there were some limited variations, these were not consistent with the local metal bioavailability nor with temperature changes. Incorporating the biodynamic parameters into a defined biodynamic model, confirmed that sediment is the predominant source of Cd and Zn accumulated by the worms, accounting in each case for 99% of the overall accumulated metals, whereas the contribution of dissolved Ag to the total accumulated by the worm increased from about 27 to about 53% with increasing dissolved Ag concentration. Standardised values of metal-specific parameters were chosen to generate a generalised model to be extended to N. diversicolor populations across a wide geographical range from western Europe to North Africa. According to the assumptions of this model, predicted steady state concentrations of Cd and Zn in N. diversicolor were overestimated, those of Ag underestimated, but still comparable to independent field measurements. We conclude that species-specific physiological metal bioaccumulation parameters are relatively constant over large geographical distances, and a single generalised biodynamic model does have potential to predict accumulated Ag, Cd and Zn concentrations in this polychaete from a single sediment metal concentration.

Bioaccumulation of arsenic from water and sediment by a deposit-feeding polychaete (Arenicola marina): a biodynamic modelling approach

Arsenic bioaccumulation in the deposit-feeding polychaete Arenicola marina has been investigated using biodynamic modelling. Radiotracer techniques were used to determine the rates of uptake of As as arsenate from water and sediment and its subsequent efflux in the laboratory. Lugworms accumulated As from solution linearly at concentrations of 2-20 microg l(-1), with a corresponding uptake rate constant of 0.1648+/-0.0135 l g(-1)d(-1). 7.8+/-0.8% (assimilation efficiency) of the As ingested bound to sediments was retained after egestion of unassimilated metal. Elimination of As followed a two-compartment model, with mean efflux rate constants (from the slow pool) very similar for As accumulated from solution and ingested sediments (0.0449+/-0.0034 and 0.0478+/-0.0225 d(-1), respectively) and a corresponding biological half-time of roughly 15 d. A biodynamic model was constructed and validated through the comparison of biodynamic model predictions against measured bioaccumulated concentrations in lugworms from five UK estuaries. The model accurately predicted bioaccumulated As concentrations in lugworms using mean values of relevant physiological parameters (uptake rate, efflux rate and growth rate constants), a site-specific ingestion rate (calculated according to mean worm size and sediment organic matter content and expressed as the rate of ingestion of the mass of fine sediment), a site-specific sediment concentration measured after HCl extraction, and a standard dissolved As concentration. This combination of parameters showed that sediment ingestion contributed 30-60% of the total As accumulated by lugworms at the studied sites, depending on the different geochemistry at each site. This study showed that it is difficult to predict accurately As bioaccumulation at sites with different chemistries, unless that chemistry is taken into account.

Phase I dose escalation trial of sorafenib as a single agent for adults with relapsed and refractory acute leukemias

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Background: Sorafenib is a multikinase inhibitor with activity against B-raf, VEGF, and FLT3. Based on preclinical activity in FLT3 mutant AML, sorafenib was studied in refractory acute leukemia. Methods: The primary objective was to determine the safety and tolerability of sorafenib in refractory acute leukemias. Secondary objectives included pharmacokinetics (PK) and pharmacodynamic (PD) effects of sorafenib on FLT3 phosphorylation. Dose escalation began at 400 mg BIDx14days per month, and proceeded through 600 mg BID x 21 days per month. Plasma concentration of sorafenib and its primary metabolite sorafenib N-oxide were measured by LC/MS//MS method. The plasma inhibitory assay was used to measure target inhibition of phosphorylated FLT3 and phosphorylated Erk. Results: Fifteen patients (13 = AML, 2 = ALL) were enrolled (ages 37–85) and treated on three dosing schedules (400 mg BID x 14 d, 400 mg BID x 21 days, 600 mg BID x 21days) of single agent sorafenib. The maximally tolerated dose was 400 mg BID x 21 days per month. Grade 3 or greater toxicities were experienced in 55% of cycles, most common grade 3 or greater toxicities being fatigue (16%) and hypokalemia (13%). No patients met criteria for complete or partial response, but 11 of 15 (73%) patients experienced stable disease as best response, with 6 showing a reduction in bone marrow blasts after only one cycle, half of who experienced a >50% reduction in bone marrow blasts. Interestingly, 2 pts with FLT3-ITD mutations both showed marrow blast response (1 pt >50%). Sorafenib resulted in sustained complete inhibition of FLT3 and Erk as demonstrated in all patients assessed (n = 11). Importantly, this inhibition was maintained throughout treatment cycle and 3/5 pts had FLT3 inhibitory activity 7 days post their last dose. Correlative studies suggest sorafenib N-oxide is an active metabolite. Conclusions: Sorafenib is a potent inhibitor of FLT3 with favorable PK and PD properties. Clinical activity as a single agent was limited to transient reductions in bone marrow blast counts and dose escalation was limited due to toxicities. Based on PK data in conjunction with standard curves for inhibition of FLT3 by sorafenib in plasma, the minimum FLT3 inhibitory dose of sorafenib is likely less than 400 mg BID.

No significant financial relationships to disclose.

Pathways of trace metal uptake in the lugworm Arenicola marina

Radiotracer techniques were used to determine the rates of trace metal (Ag, Cd and Zn) uptake and elimination (33 psu, 10 degrees C) from water and sediment by the deposit-feeding polychaete Arenicola marina, proposed as a test species for estuarine-marine sediments in whole-sediment toxicity tests. Metal uptake rates from solution increase with increasing dissolved metal concentrations, with uptake rate constants (+/-SE) (lg(-1) d(-1)) of 1.21+/-0.11 (Ag), 0.026+/-0.002 (Zn) and 0.012+/-0.001 (Cd). Assimilation efficiencies from ingested sediments were measured using a pulse-chase radiotracer feeding technique in two different lugworm populations, one from a commercial supplier (Blyth, Northumberland, UK) and the other a field-collected population from the outer Thames estuary (UK). Assimilation efficiencies ranged from 2 to 20% for Zn, 1 to 6% for Cd and 1 to 9% for Ag for the Northumberland worms, and from 3 to 22% for Zn, 6 to 70% for Cd and 2 to 15% for Ag in the case of the Thames population. Elimination of accumulated metals followed a two-compartment model, with similar efflux rate constants for Zn and Ag and lower rates of elimination of Cd from the slow pool. Efflux rate constants (+/-SE) of Zn and Ag accumulated from the dissolved phase were 0.037+/-0.002 and 0.033+/-0.006 d(-1) whereas Cd was eliminated with an efflux rate constant one order of magnitude lower (0.003+/-0.002 d(-1)). When metals were accumulated from ingested sediments, the efflux rate constants for the slow-exchanging compartment were of the same order of magnitude for the three metals, and of the same order of magnitude as those derived after the dissolved exposure for Zn and Ag (0.042+/-0.004 and 0.056+/-0.012 d(-1) for Zn and 0.044+/-0.012 and 0.069+/-0.016 d(-1) for Ag for the Northumberland and Thames populations, respectively). Cd accumulated from ingested sediments was eliminated with a rate constant not different from the fast-exchanging compartment after the water-only exposure (0.025+/-0.012 and 0.020+/-0.004 d(-1) for the Northumberland and Thames populations, respectively). A biodynamic model was used to estimate the relative importance of the dissolved phase versus ingested sediment as source of metal for the worms, showing that more than 90% of the Zn and Cd and more than 70% of Ag in lugworms is accumulated from sediment ingestion at realistic environmental concentrations. The model also shows that metal accumulation is highly dependent on the ingestion rate and assimilation efficiency.

Apparent survival, natal philopatry, and recruitment of Barrow’s goldeneyes (Bucephala islandica) in the Cariboo–Chilcotin region of British Columbia, Canada

We used capture–resight data to evaluate apparent survival, natal philopatry, and recruitment of Barrow’s goldeneyes ( Bucephala islandica (Gmelin, 1789)) in British Columbia, Canada. Median ages of first pairing and first breeding for females were 2 years and 3 years, respectively. The Cormack–Jolly–Seber model that best fit our data indicated that apparent survival rates (Φ) differed according to sex, year, and age class at marking. Estimates were similar for after-hatch-year (AHY) females (0.62) and AHY males (0.58), which was consistent with predictions. However, contrary to predictions, apparent survival rates of hatch-year (HY) females (0.68) were similar to those of AHY females and significantly higher than those of HY males (0.35). We interpret this difference as being primarily related to higher dispersal probabilities by HY males. Also evident was a negative correlation between apparent survival rate during the 1st year after capture for HY birds and their subsequent apparent survival rates, which suggests that probability of dispersal increased after these birds reached reproductive maturity and began to compete for breeding territories. We interpret this as evidence for density-dependent control of access to limited resources such as nest cavities.

The effect of surface charge, negative and bipolar ionization on the deposition of airborne bacteria

AIMS

A series of experiments were conducted to evaluate the effect of surface charge and air ionization on the deposition of airborne bacteria.

METHODS AND RESULTS

The interaction between surface electrostatic potential and the deposition of airborne bacteria in an indoor environment was investigated using settle plates charged with electric potentials of 0, +/-2.5kV and +/-5kV. Results showed that bacterial deposition on the plates increased proportionally with increased potential to over twice the gravitational sedimentation rate at +5kV. Experiments were repeated under similar conditions in the presence of either negative or bipolar air ionization. Bipolar air ionization resulted in reduction of bacterial deposition onto the charged surfaces to levels nearly equal to gravitational sedimentation. In contrast, diffusion charging appears to have occurred during negative air ionization, resulting in an even greater deposition onto the oppositely charged surface than observed without ionization.

CONCLUSIONS

Static charges on fomitic surfaces may attract bacteria resulting in deposition in excess of that expected by gravitational sedimentation or simple diffusion. Implementation of bipolar ionization may result in reduction of bacterial deposition.

SIGNIFICANCE AND IMPACT OF STUDY

Fomitic surfaces are important vehicles for the transmission of infectious organisms. This study has demonstrated a simple strategy for minimizing charge related deposition of bacteria on surfaces.