Targeting Conservation Investments in Heterogeneous Landscapes: A distance function approach and application to watershed management

To achieve a given level of an environmental amenity at least cost, decision-makers must integrate information about spatially variable biophysical and economic conditions. Although the biophysical attributes that contribute to supplying an environmental amenity are often known, the way in which these attributes interact to produce the amenity is often unknown. Given the difficulty in converting multiple attributes into a unidimensional physical measure of an environmental amenity (e.g., habitat quality), analyses in the academic literature tend to use a single biophysical attribute as a proxy for the environmental amenity (e.g., species richness). A narrow focus on a single attribute, however, fails to consider the full range of biophysical attributes that are critical to the supply of an environmental amenity. Drawing on the production efficiency literature, we introduce an alternative conservation targeting approach that relies on distance functions to cost-efficiently allocate conservation funds across a spatially heterogeneous landscape. An approach based on distance functions has the advantage of not requiring a parametric specification of the amenity function (or cost function), but rather only requiring that the decision-maker identify important biophysical and economic attributes. We apply the distance-function approach empirically to an increasingly common, but little studied, conservation initiative: conservation contracting for water quality objectives. The contract portfolios derived from the distance-function application have many desirable properties, including intuitive appeal, robust performance across plausible parametric amenity measures, and the generation of ranking measures that can be easily used by field practitioners in complex decision-making environments that cannot be completely modeled. Working Paper # 2002-01

Efficacy of α-Blockers on Hemodynamic Control during Pheochromocytoma Resection: A Randomized Controlled Trial

CONTEXT: Pretreatment with α-adrenergic receptor blockers is recommended to prevent hemodynamic instability during resection of a pheochromocytoma or sympathetic paraganglioma (PPGL). OBJECTIVE: To determine which type of α-adrenergic receptor blocker provides the best efficacy. DESIGN: Randomized controlled open-label trial (PRESCRIPT; ClinicalTrials.gov NCT01379898). SETTING: Multicenter study including 9 centers in The Netherlands. PATIENTS: 134 patients with nonmetastatic PPGL. INTERVENTION: Phenoxybenzamine or doxazosin starting 2 to 3 weeks before surgery using a blood pressure targeted titration schedule. Intraoperative hemodynamic management was standardized. MAIN OUTCOME MEASURES: Primary efficacy endpoint was the cumulative intraoperative time outside the blood pressure target range (ie, SBP >160 mmHg or MAP <60 mmHg) expressed as a percentage of total surgical procedure time. Secondary efficacy endpoint was the value on a hemodynamic instability score. RESULTS: Median cumulative time outside blood pressure targets was 11.1% (interquartile range [IQR]: 4.3-20.6] in the phenoxybenzamine group compared to 12.2% (5.3-20.2)] in the doxazosin group (P = .75, r = 0.03). The hemodynamic instability score was 38.0 (28.8-58.0) and 50.0 (35.3-63.8) in the phenoxybenzamine and doxazosin group, respectively (P = .02, r = 0.20). The 30-day cardiovascular complication rate was 8.8% and 6.9% in the phenoxybenzamine and doxazosin group, respectively (P = .68). There was no mortality after 30 days. CONCLUSIONS: The duration of blood pressure outside the target range during resection of a PPGL was not different after preoperative treatment with either phenoxybenzamine or doxazosin. Phenoxybenzamine was more effective in preventing intraoperative hemodynamic instability, but it could not be established whether this was associated with a better clinical outcome

Internal mammary lymph drainage and sentinel node biopsy in breast cancer - A study on 1008 patients.

INTRODUCTION: Nowadays, axillary sentinel node (SN) biopsy is a standard procedure in the staging of breast cancer. Although the internal mammary (IM) lymph node status is a major independent prognostic factor in breast cancer patients, sampling of IM sentinel nodes (IMSNs) is not performed routinely. The aim of this study was to determine the likelihood of finding IM lymph node metastases in case of IM hotspots on lymphoscintigraphy and evaluate the relevance of IMSN biopsy as a method to improve staging. PATIENTS AND METHODS: Between April 1997 and May 2006, a total of 1008 consecutive patients with clinically node-negative operable primary breast cancer were enrolled in a prospective study on SN biopsy. Both axillary and IMSNs were sampled, based on lymphoscintigraphy, intraoperative gamma probe detection and blue dye mapping, using 10mCi (370MBq) (99m)Tc-nanocolloid injected peritumorally, and 0.5-1.0ml Patent Blue V injected intradermally. RESULTS: Lymphoscintigraphy showed axillary sentinel nodes in 98% (989/1008) and IMSNs in 20% of the patients (196/1008). Sampling the IM basin, as based on the results of lymphoscintigraphy, was successful in 71% of the patients (139/196) and revealed metastases in 22% (31/139). In 29% of the patients with positive IMSNs (9/31) no axillary metastases were found. CONCLUSION: Evaluation of IMSNs improves nodal staging in breast cancer. Patients with IM hotspots on lymphoscintigraphy have a substantial risk (22%) of metastatic involvement of the IM chain. In addition, true IM node-negative patients can be spared the morbidity associated with adjuvant radiotherapy

Prevalence of lymphoedema more than five years after breast cancer treatment

AbstractAimA lack of consistency in the definition of breast cancer related lymphoedema (BCRL) and of uniform measurement criteria contribute to the wide prevalence range found in current literature. This report aims to describe the long-term prevalence of BCRL and secondly, to compare the long-term prevalence of BCRL when assessed by two objective measures and one subjective measure.MethodsThe upper-limbs of 145 post-surgical breast cancer patients were evaluated for the presence of lymphoedema using the water displacement method. Two circumference methods and patient perceived swelling were applied secondarily for comparison. Limb measurements were performed once, more than five years after surgery.ResultsThe long-term prevalence of BCRL using water displacement was 8%. Prevalence varied when the sum of arm circumference (SOAC), the arm circumference and the self-report methods were used: 16, 31 and 17% [P < 0.001], respectively. Of the women identified with BCRL using the water displacement technique, 82% were detected with the SOAC method, 82% with the arm circumference method and 91% by self-report. Using water displacement as the gold standard the methods with the highest specificities were the SOAC (90%) and self-report method (89%), arm circumference resulted in a low specificity of 73%.ConclusionThe prevalence of BCRL more than five years after surgical treatment differs depending on the measuring method used. Our data underlines the necessity for consensus on the diagnostic criteria for BCRL

Results of tailored treatment for breast cancer patients with internal mammary lymph node metastases

Although the internal mammary (IM) lymph node status is a major prognostic factor in breast cancer, IM nodal staging is not common practice. In order to improve nodal staging, we have routinely performed IM sentinel node (SN) biopsy and have adjusted adjuvant treatment accordingly. We reviewed the outcome of these patients. Data from 764 patients were available for follow-up. A total of 406 patients had no lymph node metastases (group 1), 330 patients had axillary metastases (group 2), 7 patients had IM metastases only (group 3) and 21 patients had both axillary and IM metastases (group 4). Mean follow-up was 46 months. Prognosis did not appear to be worse for patients with IM metastases compared to those with axillary metastases only, which might indicate that they benefit from improved staging and tailored adjuvant treatment algorithms. However, long-term follow-up data, preferably in larger series, are needed to support our findings

The Quality of Life in Long-Term Breast Cancer Survivors with Breast Cancer Related Lymphedema

Aim : To compare the health related quality of life (HRQOL) of long-term breast cancer survivors with and without breast cancer related lymphedema (BCRL) treated in the sentinel lymph node biopsy (SLNB) era. Methods : HRQOL was assessed as subject of a secondary analysis of data gathered for a study evaluating the prevalence of BCRL in long-term breast cancer survivors. The 145 women in this study cohort had undergone SLNB and or axillary, lymph node dissection (ALND) according to Dutch Breast cancer treatment guidelines. HRQOL was assessed using two questionnaires : the European Organization for Research and Treatment of Cancer Quality (QLQ-C30) and the Breast Cancer-specific Quality of life questionnaire (QLQ-BR23). Results : Twenty-six women, of whom 5 only underwent SLNB, were identified with objectively measured lymphedema and/or self-perceived arm swelling. Patients with BCRL scored significantly lower on the social (p = 0.000) functioning scale after adjustment for BMI and age compared to women without BCRL. Compared to normative data, women with BCRL scored significantly lower on social- (p <0.001) and role (p = 0.001) functioning scales. Conclusion : HRQOL in long-term breast cancer survivors with BCRL is structurally lower than of those without BCRL, even in this small cohort of cancer survivors treated in the SLNB-era

Surgical resection of the primary tumour is associated with improved survival in patients with distant metastatic breast cancer at diagnosis

International audienceRecent studies indicate that removal of the primary tumour may have a beneficial effect on mortality risk of patients with primary distant metastatic breast cancer (stage IV), although most of them did not rule out confounding by the presence of comorbidity. In this retrospective study the impact of surgical resection of the primary tumour on the survival of patients with primary distant metastatic disease is investigated, taking into account the presence of comorbidity and other potential confounders

The changing role of axillary treatment in breast cancer: Who will remain at risk for developing arm morbidity in the future?

Primary aim is to give an overview of changes in axillary staging and treatment of breast cancer patients. Secondly, we aim to identify patients with a high arm/shoulder morbidity risk, and describe a strategy to improve early detection and treatment. Recent and initiated studies on axillary staging and treatment were evaluated and clustered for clinically node negative and clinically node positive breast cancer patients, together with studies on pathology, detection and (surgical) prevention and treatment of lymphedema. For clinically node negative patients, the indication for axillary lymph node dissection in sentinel node positive patients is fading. On the contrary, clinically node positive patients are routinely subjected to an axillary lymph node dissection, in combination with other therapies associated with an increased lymphedema risk, such as mastectomy, adjuvant radiation- and (taxane-based) chemotherapy. Techniques for prevention, early detection and (surgical) treatment of lymphedema are being developed. Axillary staging and treatment in breast cancer patients with a clinically node negative status will become less invasive, thereby reducing the incidence of morbidity. Nevertheless, in patients with a clinically node positive status, aggressive treatment will still be required for oncologic control. For these patients, a surveillance program should be implemented in order to apply (curative) surgical treatment for lymphedema