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Featured researches published by Alexander Liede.


Prostate Cancer and Prostatic Diseases | 2015

Predicting bone scan positivity in non-metastatic castration-resistant prostate cancer

Daniel M. Moreira; Lauren E. Howard; Katie Sourbeer; Hiruni S. Amarasekara; Lydia C. Chow; Dillon C. Cockrell; Brian T. Hanyok; Connor L. Pratson; William J. Aronson; Christopher J. Kane; Martha K. Terris; Christopher L. Amling; Matthew R. Cooperberg; Alexander Liede; Stephen J. Freedland

Background:To evaluate PSA levels and kinetic cutoffs to predict positive bone scans for men with non-metastatic castration-resistant prostate cancer (CRPC) from the Shared Equal Access Regional Cancer Hospital (SEARCH) cohort.Methods:Retrospective analysis of 531 bone scans of 312 clinically CRPC patients with no known metastases at baseline treated with a variety of primary treatment types in the SEARCH database. The association of patients’ demographics, pathological features, PSA levels and kinetics with risk of a positive scan was tested using generalized estimating equations.Results:A total of 149 (28%) scans were positive. Positive scans were associated with younger age (odds ratio (OR)=0.98; P=0.014), higher Gleason scores (relative to Gleason 2–6, Gleason 3+4: OR=2.03, P=0.035; Gleason 4+3 and 8–10: OR=1.76, P=0.059), higher prescan PSA (OR=2.11; P<0.001), shorter prescan PSA doubling time (PSADT; OR=0.53; P<0.001), higher PSA velocity (OR=1.74; P<0.001) and more remote scan year (OR=0.92; P=0.004). Scan positivity was 6, 14, 29 and 57% for men with PSA<5, 5–14.9, 15–49.9 and ⩾50 ng ml−1, respectively (P-trend <0.001). Men with PSADT ⩾15, 9–14.9, 3–8.9 and <3 months had a scan positivity of 11, 22, 34 and 47%, correspondingly (P-trend <0.001). Tables were constructed using PSA and PSADT to predict the likelihood of a positive bone scan.Conclusions:PSA levels and kinetics were associated with positive bone scans. We developed tables to predict the risk of positive bone scans by PSA and PSADT. Combining PSA levels and kinetics may help select patients with CRPC for bone scans.


Journal of Bone and Joint Surgery, American Volume | 2015

Incidence Trends in the Diagnosis of Giant Cell Tumor of Bone in Sweden Since 1958.

Julia Rockberg; Bruce A. Bach; Justyna Amelio; Rohini K. Hernandez; P. Sobocki; Jacob Engellau; Henrik C. F. Bauer; Alexander Liede

BACKGROUND The Swedish Cancer Registry (founded in 1958) constitutes a unique resource for epidemiological studies of giant cell tumor of bone with potential for use for population-based studies of incidence over time. The aim of this study was to provide what we believe is the first modern population-based assessment of the incidence trends of giant cell tumor, a unique osteoclastogenic lytic stromal tumor with both benign and malignant histological forms, and to compare the findings with data from the same registry on osteosarcoma, a tumor that may display similar histological characteristics. METHODS Cases were identified with use of codes for pathological bone tumor (International Classification of Diseases [ICD]-7 196). Specific morphological coding distinguishes benign (PAD 741) from malignant giant cell tumor (PAD 746) and osteosarcoma (PAD 766). RESULTS During the period of 1958 to 2011, 4625 bone tumors were reported, including 505 giant cell tumors (383 benign and 122 malignant) and 1152 osteosarcomas. From 1958 to 1982 the ratio of malignant to benign giant cell tumors was 1.3, whereas from 1983 to 2011 the ratio inverted to 0.09, suggesting a change in the reporting or diagnosis of malignant or benign cases. Cases of giant cell tumor diagnosed from 1983 to 2011 displayed an age and sex distribution (median age at diagnosis, 34.0 years; 54% female) that were consistent with those in large published case series but differed from those in 1958 to 1982 (median age at diagnosis, 31.5 years; 48% female). The most current data (1983 to 2011) showed the giant cell tumor incidence in Sweden to be 1.3 per million per year, while the osteosarcoma incidence was 2.3 per million per year. CONCLUSIONS Early Swedish Cancer Registry data (1958 to 1982) revealed a higher proportion of malignant giant cell tumors than seen in large sequential case series and a distinct age and sex profile compared with more recent data (1983 to 2011). This likely represents changes in the diagnostic workup and introduction of multidisciplinary review of giant-cell-containing tumors around 1982. Recent data may reflect the impact of expert centralized biopsy and multidisciplinary case review and more comprehensive reporting of benign giant cell tumors.


Cancer Epidemiology | 2015

Prevalence of hypercalcemia of malignancy among cancer patients in the UK: analysis of the Clinical Practice Research Datalink database

Susan S. Jick; Lin Li; Victor M. Gastanaga; Alexander Liede

BACKGROUND The reported proportion of cancer patients who experience hypercalcemia of malignancy (HCM) ranges between 3% and 30%. HCM can be observed with any type of tumor and occurs most commonly in lung cancer, breast cancer and multiple myeloma. While HCM is a potentially fatal condition, the prevalence of HCM is not well defined. METHODS Using the United Kingdom Clinical Practice Research Datalink, we identified adult cancer patients with recorded corrected serum calcium (CSC). Hypercalcemic patients (CSC ≥ 10.8 mg/dL) were classified into 4 CSC levels. We estimated annual prevalence of HCM overall, stratified by cancer type, and in patients with stage IV cancer. RESULTS Among 37,442 cancer patients in 2003-2012 the prevalence of grade 1 HCM increased from 0.13% to 0.45% and the prevalence of HCM overall (grade 1 or higher) increased from 0.20% to 0.67% over the study period. Prevalence estimates varied across cancer type and were highest for lung cancer, multiple myeloma and patients with stage IV cancer. CONCLUSION We provide the first systematic analysis using a UK population-based data source to estimate number of cancer patients affected with HCM by grade. The increase in HCM prevalence over the 10-year study period is likely due to the increased recording of laboratory values, particularly comparing more recent data to 2003. Our findings suggest that HCM in general is not a common condition.


Journal of Bone and Joint Surgery, American Volume | 2014

Regional Variation and Challenges in Estimating the Incidence of Giant Cell Tumor of Bone

Alexander Liede; Bruce A. Bach; Scott Stryker; Rohini K. Hernandez; P. Sobocki; Brian Bennett; Steven S. Wong

BACKGROUND Estimating the incidence of giant cell tumor of bone is challenging because few population-based cancer registries record benign bone tumors. We compared two approaches, the indirect (relative index) estimation approach used in The Burden of Musculoskeletal Diseases in the United States (BMUS) and a direct incidence rate approach (from registries that record giant cell tumor), to estimate giant cell tumor incidence in France, Germany, Italy, Spain, the U.K., Sweden, Australia, Canada, Japan, and the U.S. METHODS Giant cell tumor of bone incidence was calculated with use of the BMUS relative index of giant cell tumor to osteosarcoma in three scenarios (low, base case, and high) from case series. We compared the BMUS approach with the latest data from tumor registries in Australia (1972 to 1996), Japan (2006 to 2008), and Sweden (1993 to 2011) that record giant cell tumors. United Nations population estimates were used to project results to 2013. RESULTS The low scenario in the BMUS approach reflects data from Unni and Inwards; the incidence of giant cell tumor of bone is 0.34 relative to osteosarcoma. As the incidence of osteosarcoma is 31.4% of the total incidence of bone and joint cancers, the incidence of giant cell tumor is 0.11 times that of all bone and joint cancers. The base scenario reflects the series by Mirra et al., with a giant cell tumor incidence of 0.47 relative to osteosarcoma (0.15 to all bone and joint cancers). The high scenario reflects the series by Ward, with an incidence of 0.84 relative to osteosarcoma (0.26 to all bone and joint cancers). Differences among the three series reflect referral to a national center of excellence compared with referral to a local oncology practice. Registry data indicated a giant cell tumor incidence rate per million per year of 1.33 in Australia, 1.03 in Japan, and 1.11 in Sweden in 2013. The estimated incidence rate per million in the ten countries in 2013 ranged from 1.03 (Japan) to 1.17 (Canada) with use of the registry-based approach and from 0.73 (Japan) for the low scenario) to 2.20 (Germany) for the base case with use of the BMUS approach. CONCLUSIONS Giant cell tumor of bone affects approximately one person per million per year in the ten countries studied. Estimates derived with use of age-specific incidences from tumor registries were typically within the range of the low and base case BMUS scenarios. We recommend the registry-derived method for estimating the incidence of giant cell tumor.


Clinical Epidemiology | 2017

Use of the Medicare database in epidemiologic and health services research: a valuable source of real-world evidence on the older and disabled populations in the US

Katherine Mues; Alexander Liede; Jiannong Liu; James B. Wetmore; Rebecca Zaha; Brian D. Bradbury; Allan J. Collins; David T. Gilbertson

Medicare is the federal health insurance program for individuals in the US who are aged ≥65 years, select individuals with disabilities aged <65 years, and individuals with end-stage renal disease. The Centers for Medicare and Medicaid Services grants researchers access to Medicare administrative claims databases for epidemiologic and health outcomes research. The data cover beneficiaries’ encounters with the health care system and receipt of therapeutic interventions, including medications, procedures, and services. Medicare data have been used to describe patterns of morbidity and mortality, describe burden of disease, compare effectiveness of pharmacologic therapies, examine cost of care, evaluate the effects of provider practices on the delivery of care and patient outcomes, and explore the health impacts of important Medicare policy changes. Considering that the vast majority of US citizens ≥65 years of age have Medicare insurance, analyses of Medicare data are now essential for understanding the provision of health care among older individuals in the US and are critical for providing real-world evidence to guide decision makers. This review is designed to provide researchers with a summary of Medicare data, including the types of data that are captured, and how they may be used in epidemiologic and health outcomes research. We highlight strengths, limitations, and key considerations when designing a study using Medicare data. Additionally, we illustrate the potential impact that Centers for Medicare and Medicaid Services policy changes may have on data collection, coding, and ultimately on findings derived from the data.


Cancer Medicine | 2016

Prevalence of hypercalcemia among cancer patients in the United States.

Victor M. Gastanaga; Lee S. Schwartzberg; Rajul K. Jain; Melissa Pirolli; David Quach; Jane Quigley; George Mu; W. Scott Stryker; Alexander Liede

Hypercalcemia of malignancy (HCM) is a serious metabolic complication whose population‐based prevalence has not been quantified. Rates of HCM differ by tumor type, with highest rates reported in multiple myeloma and lowest among colorectal and prostate cancer patients. This analysis estimates HCM prevalence in the US. This retrospective study used the Oncology Services Comprehensive Electronic Records (OSCER) warehouse of electronic health records (EHR) including laboratory values from 569000 patients treated at 565 oncology outpatient sites. OSCER data were projected to the national level by linking EHR to claims data. Cancer patients included were ≥18 years, and had serum calcium (Ca) and albumin (for corrected serum Ca [CSC]) records. Period prevalence was estimated by HCM CTCAE grade, tumor type, and year (2009–2013). Estimates were adjusted to capture patients diagnosed with HCM outside oncology practices based on a subset of patients linkable to office and hospital data. The analysis included 68023 (2009) to 121482 (2013) cancer patients. In 2013, patients with HCM had a median of six Ca tests, 69.7% had chemotherapy, and 34% received bone modifying agents. HCM rates were highest for multiple myeloma patients (7.5% [2012]–10.2% [2010]), lowest for prostate cancer (1.4% [2012]–2.1% [2011]).The estimated adjusted annual prevalence of HCM from 2009 to 2013 was 95441, 96281, 89797, 70158, and 71744, respectively. HCM affected 2.0–2.8% of all cancer patients. EHR data from oncology clinics were critical for this study because these data contain results from laboratory studies (i.e., serum calcium values) that are routinely ordered in that setting. We estimated that the prevalence of HCM in the US in 2013 is 71744, affecting approximately 2% of cancer patients overall. This percentage differs by tumor type and appears to have decreased over the five‐year study period.


Clinical Epidemiology | 2015

Prevalence of bone metastases and bone-targeting agent use among solid tumor patients in the United States

Rohini K. Hernandez; Avanti Adhia; Sally W. Wade; Emily O'Connor; Jorge Arellano; Kevin Francis; Hasmik Alvrtsyan; Ryan P Million; Alexander Liede

Purpose Patients with bone metastases are at an increased risk of experiencing morbidity due to bone complications, and bone-targeting agents (BTA) are indicated for the prevention of these complications. Population-based estimates of the prevalence of bone metastases associated with solid tumors, and current treatment patterns for these patients, are limited. This study was undertaken to estimate the prevalence of bone metastases from solid tumors and to describe recent trends in the use of BTA in the US. Methods We estimated the prevalence of bone metastases in the US in 2012 using data from Medicare fee-for-service and PharMetrics Plus, a large commercial claims database. We evaluated the proportion of patients with bone metastases who were treated with BTA in 2012, timing of initiation of BTA relative to bone metastasis diagnosis, and persistence on BTA, overall and by primary tumor type and treatment. Results There were ~330,000 (168,063 Medicare fee-for-service; 162,239 other) patients aged ≥18 years living with solid tumors and bone metastases in 2012. BTA were used by 43% (Commercial) to 47% (Medicare) of patients in 2012, with the greatest use among breast cancer patients. Over half (Medicare: 57%; Commercial: 53%) of BTA-treated patients initiated BTA after experiencing a bone complication. Conclusion Of the estimated 330,000 solid tumor patients living with bone metastases in the US in 2012, many may have received less than optimal care to prevent bone complications during the calendar year.


Clinical Epidemiology | 2015

Validation of International Classification of Diseases coding for bone metastases in electronic health records using technology-enabled abstraction.

Alexander Liede; Rohini K. Hernandez; Maayan Roth; Geoffrey Calkins; Katherine Larrabee; Leo Viana Nicacio

Objective The accuracy of bone metastases diagnostic coding based on International Classification of Diseases, ninth revision (ICD-9) is unknown for most large databases used for epidemiologic research in the US. Electronic health records (EHR) are the preferred source of data, but often clinically relevant data occur only as unstructured free text. We examined the validity of bone metastases ICD-9 coding in structured EHR and administrative claims relative to the complete (structured and unstructured) patient chart obtained through technology-enabled chart abstraction. Patients and methods Female patients with breast cancer with ≥1 visit after November 2010 were identified from three community oncology practices in the US. We calculated sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of bone metastases ICD-9 code 198.5. The technology-enabled abstraction displays portions of the chart to clinically trained abstractors for targeted review, thereby maximizing efficiency. We evaluated effects of misclassification of patients developing skeletal complications or treated with bone-targeting agents (BTAs), and timing of BTA. Results Among 8,796 patients with breast cancer, 524 had confirmed bone metastases using chart abstraction. Sensitivity was 0.67 (95% confidence interval [CI] =0.63–0.71) based on structured EHR, and specificity was high at 0.98 (95% CI =0.98–0.99) with corresponding PPV of 0.71 (95% CI =0.67–0.75) and NPV of 0.98 (95% CI =0.98–0.98). From claims, sensitivity was 0.78 (95% CI =0.74–0.81), and specificity was 0.98 (95% CI =0.98–0.98) with PPV of 0.72 (95% CI =0.68–0.76) and NPV of 0.99 (95% CI =0.98–0.99). Structured data and claims missed 17% of bone metastases (89 of 524). False negatives were associated with measurable overestimation of the proportion treated with BTA or with a skeletal complication. Median date of diagnosis was delayed in structured data (32 days) and claims (43 days) compared with technology-assisted EHR. Conclusion Technology-enabled chart abstraction of unstructured EHR greatly improves data quality, minimizing false negatives when identifying patients with bone metastases that may lead to inaccurate conclusions that can affect delivery of care.


Cancer Epidemiology | 2016

Population-based study of giant cell tumor of bone in Sweden (1983–2011)

Justyna Amelio; Julia Rockberg; Rohini K. Hernandez; Patrik Sobocki; Scott Stryker; Bruce A. Bach; Jacob Engellau; Alexander Liede

INTRODUCTION Giant-cell tumor of bone (GCTB) is a locally aggressive histologically benign neoplasm with a less common malignant counterpart. Longitudinal data sources on GCTB are sparse, limited to single institution case series or surgical outcomes studies. The Swedish Cancer Registry is one of the few national population-based databases recording GCTB, representing a unique source to study GCTB epidemiology. We estimated incidence rate (IR) and overall mortality rates based on registry data. MATERIALS AND METHODS We identified patients with a GCTB diagnosis in the Swedish Cancer Registry from 1983 to 2011: benign (ICD-7 196.0-196.9; PAD 741) and malignant (PAD 746). Results were stratified by age at diagnosis, gender, and anatomical lesion location. RESULTS The cohort included 337 GCTB cases (IR of 1.3 per million persons per year). The majority (n=310) had primary benign GCTB (IR of 1.2 per million per year). Median age at diagnosis was 34 years (range 10-88) with 54% (n=183) females. Malignant to benign ratio for women was 0.095 (16/167) and for men 0.077 (11/143). Incidence was highest in the 20-39 years age group (IR of 2.1 per million per year). The most common lesion sites were distal femur and proximal tibia. Mortality at 20 years from diagnosis was 14% (n=48) and was slightly higher for axial (17%; n=6) and pelvic (17%; n=4) lesions. Recurrence occurred in 39% of primary benign cases and 75% of primary malignant cases. CONCLUSIONS In our modern population-based series primary malignant cases were uncommon (8%), peak incidence 20-39 years with slight predominance in women. Recurrence rates remain significant with overall 39% occurring in benign GCTB, and 75% in malignant form. The linkage between databases allowed the first population based estimates of the proportion of patients who received surgery at initial GCTB diagnosis, and those who also received subsequent surgeries.


ESMO open | 2016

International survey of androgen deprivation therapy (ADT) for non-metastatic prostate cancer in 19 countries.

Alexander Liede; David Hallett; Kirsty Hope; Alex Graham; Jorge Arellano; Vahakn B. Shahinian

Background Continuous androgen deprivation therapy (CADT) is commonly used for patients with non-metastatic prostate cancer as primary therapy for high-risk disease, adjuvant therapy together with radiation or for recurrence after initial local therapy. Intermittent ADT (IADT), a recently developed alternative strategy for providing ADT, is thought to potentially reduce adverse effects, but little is known about practice patterns relating to it. We aimed to describe factors related to physicians’ ADT use and modality for patients with non-metastatic prostate cancer. Methods A 45 min online survey was completed by urologists and oncologists responsible for treatment decisions for non-metastatic prostate cancer from 19 countries with high or increasing prevalence of non-metastatic prostate cancer. Results There were 441 treating physicians who completed the survey which represented 99 177 patients with prostate cancer under their care, of which 76 386 (77%) had non-metastatic prostate cancer. Of patients with non-metastatic prostate cancer, 38% received ADT (37% gonadotropin-releasing hormone (GnRH), 2% orchiectomy); among patients on GnRH, 54% received CADT (≥6 without >3 months interruption), 23% IADT and 23% <6 months. Highest rates of ADT were reported among oncologists (62%) and in Eastern Europe (Czech Republic, Hungary and Poland). Prostate-specific antigen (PSA) levels (65%), Gleason score (52%) and treatment guidelines (48%) were the most common reasons for CADT whereas PSA levels (54%), patient request (48%), desire to maintain sexual function (40%), patient age and comorbidities (38%) were cited most frequently as reasons for IADT. Conclusions This international survey with 441 treating physicians from 19 countries showed that ADT is commonly used in treating patients with non-metastatic prostate cancer, and type of ADT is influenced by high-risk criteria (PSA and Gleason), treatment guidelines and patient preferences. IADT use was primarily driven by PSA levels, patient request and patient age/comorbidities, likely reflecting an attempt to minimise adverse effects of ADT in patients with lower risk tumours.

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