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Rahib L, Smith BD, Aizenberg R, Rosenzweig AB, Fleshman JM, Matrisian LM. Projecting Cancer Incidence and Deaths to 2030: The Unexpected Burden of Thyroid, Liver, and Pancreas Cancers in the United States. Cancer Res 2014; 74:2913-21. [PMID: 24840647 DOI: 10.1158/0008-5472.can-14-0155] [Citation(s) in RCA: 5005] [Impact Index Per Article: 455.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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11 |
5005 |
2
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Smith BD, Smith GL, Hurria A, Hortobagyi GN, Buchholz TA. Future of cancer incidence in the United States: burdens upon an aging, changing nation. J Clin Oncol 2009; 27:2758-65. [PMID: 19403886 DOI: 10.1200/jco.2008.20.8983] [Citation(s) in RCA: 1293] [Impact Index Per Article: 80.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
PURPOSE By 2030, the United States' population will increase to approximately 365 million, including 72 million older adults (age > or = 65 years) and 157 million minority individuals. Although cancer incidence varies by age and race, the impact of demographic changes on cancer incidence has not been fully characterized. We sought to estimate the number of cancer patients diagnosed in the United States through 2030 by age and race. METHODS Current demographic-specific cancer incidence rates were calculated using the Surveillance Epidemiology and End Results database. Population projections from the Census Bureau were used to project future cancer incidence through 2030. RESULTS From 2010 to 2030, the total projected cancer incidence will increase by approximately 45%, from 1.6 million in 2010 to 2.3 million in 2030. This increase is driven by cancer diagnosed in older adults and minorities. A 67% increase in cancer incidence is anticipated for older adults, compared with an 11% increase for younger adults. A 99% increase is anticipated for minorities, compared with a 31% increase for whites. From 2010 to 2030, the percentage of all cancers diagnosed in older adults will increase from 61% to 70%, and the percentage of all cancers diagnosed in minorities will increase from 21% to 28%. CONCLUSION Demographic changes in the United States will result in a marked increase in the number of cancer diagnoses over the next 20 years. Continued efforts are needed to improve cancer care for older adults and minorities.
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Journal Article |
16 |
1293 |
3
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Caudle AS, Yang WT, Krishnamurthy S, Mittendorf EA, Black DM, Gilcrease MZ, Bedrosian I, Hobbs BP, DeSnyder SM, Hwang RF, Adrada BE, Shaitelman SF, Chavez-MacGregor M, Smith BD, Candelaria RP, Babiera GV, Dogan BE, Santiago L, Hunt KK, Kuerer HM. Improved Axillary Evaluation Following Neoadjuvant Therapy for Patients With Node-Positive Breast Cancer Using Selective Evaluation of Clipped Nodes: Implementation of Targeted Axillary Dissection. J Clin Oncol 2016; 34:1072-8. [PMID: 26811528 DOI: 10.1200/jco.2015.64.0094] [Citation(s) in RCA: 626] [Impact Index Per Article: 69.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
PURPOSE Placing clips in nodes with biopsy-confirmed metastasis before initiating neoadjuvant therapy allows for evaluation of response in breast cancer. Our goal was to determine if pathologic changes in clipped nodes reflect the status of the nodal basin and if targeted axillary dissection (TAD), which includes sentinel lymph node dissection (SLND) and selective localization and removal of clipped nodes, improves the false-negative rate (FNR) compared with SLND alone. METHODS A prospective study of patients with biopsy-confirmed nodal metastases with a clip placed in the sampled node was performed. After neoadjuvant therapy, patients underwent axillary surgery and the pathology of the clipped node was compared with other nodes. Patients undergoing TAD had SLND and selective removal of the clipped node using iodine-125 seed localization. The FNR was determined in patients undergoing complete axillary lymphadenectomy (ALND). RESULTS Of 208 patients enrolled in this study, 191 underwent ALND, with residual disease identified in 120 (63%). The clipped node revealed metastases in 115 patients, resulting in an FNR of 4.2% (95% CI, 1.4 to 9.5) for the clipped node. In patients undergoing SLND and ALND (n = 118), the FNR was 10.1% (95% CI, 4.2 to 19.8), which included seven false-negative events in 69 patients with residual disease. Adding evaluation of the clipped node reduced the FNR to 1.4% (95% CI, 0.03 to 7.3; P = .03). The clipped node was not retrieved as an SLN in 23% (31 of 134) of patients, including six with negative SLNs but metastasis in the clipped node. TAD followed by ALND was performed in 85 patients, with an FNR of 2.0% (1 of 50; 95% CI, 0.05 to 10.7). CONCLUSION Marking nodes with biopsy-confirmed metastatic disease allows for selective removal and improves pathologic evaluation for residual nodal disease after chemotherapy.
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Research Support, Non-U.S. Gov't |
9 |
626 |
4
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Correa C, Harris EE, Leonardi MC, Smith BD, Taghian AG, Thompson AM, White J, Harris JR. Accelerated Partial Breast Irradiation: Executive summary for the update of an ASTRO Evidence-Based Consensus Statement. Pract Radiat Oncol 2016; 7:73-79. [PMID: 27866865 DOI: 10.1016/j.prro.2016.09.007] [Citation(s) in RCA: 446] [Impact Index Per Article: 49.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Accepted: 09/12/2016] [Indexed: 11/28/2022]
Abstract
PURPOSE To update the accelerated partial breast irradiation Consensus Statement published in 2009 and provide guidance on use of intraoperative radiation therapy (IORT) for partial breast irradiation in early-stage breast cancer, based on published evidence complemented by expert opinion. METHODS AND MATERIALS A systematic PubMed search using the same terms as the original Consensus Statement yielded 419 articles; 44 articles were selected. The authors synthesized the published evidence and, through a series of conference calls and e-mails, reached consensus regarding the recommendations. RESULTS The new recommendations include lowering the age in the "suitability group" from 60 to 50 years and in the "cautionary group" to 40 years for patients who meet all other elements of suitability (Table 1). Patients with low-risk ductal carcinoma in situ, as per Radiation Therapy Oncology Group 9804 criteria, were categorized in the "suitable" group. The task force agreed to maintain the current criteria based on margin status. Recommendations for the use of IORT for breast cancer patients include: counseling patients regarding the higher risk of ipsilateral breast tumor recurrence with IORT compared with whole breast irradiation; the need for prospective monitoring of long-term local control and toxicity with low-energy radiograph IORT given limited follow-up; and restriction of IORT to women with invasive cancer considered "suitable." CONCLUSION These recommendations will provide updated clinical guidance regarding use of accelerated partial breast irradiation for radiation oncologists and other specialists participating in the care of breast cancer patients.
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Journal Article |
9 |
446 |
5
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Jagsi R, Jiang J, Momoh AO, Alderman A, Giordano SH, Buchholz TA, Kronowitz SJ, Smith BD. Trends and variation in use of breast reconstruction in patients with breast cancer undergoing mastectomy in the United States. J Clin Oncol 2014; 32:919-26. [PMID: 24550418 DOI: 10.1200/jco.2013.52.2284] [Citation(s) in RCA: 347] [Impact Index Per Article: 31.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
PURPOSE Concerns exist regarding breast cancer patients' access to breast reconstruction, which provides important psychosocial benefits. PATIENTS AND METHODS Using the MarketScan database, a claims-based data set of US patients with employment-based insurance, we identified 20,560 women undergoing mastectomy for breast cancer from 1998 to 2007. We evaluated time trends using the Cochran-Armitage test and correlated reconstruction use with plastic-surgery workforce density and other treatments using multivariable regression. RESULTS Median age of our sample was 51 years. Reconstruction use increased from 46% in 1998 to 63% in 2007 (P < .001), with increased use of implants and decreased use of autologous techniques over time (P < .001). Receipt of bilateral mastectomy also increased: from 3% in 1998 to 18% in 2007 (P < .001). Patients receiving bilateral mastectomy were more likely to receive reconstruction (odds ratio [OR], 2.3; P < .001) and patients receiving radiation were less likely to receive reconstruction (OR, 0.44; P < .001). Rates of reconstruction receipt varied dramatically by geographic region, with associations with plastic surgeon density in each state and county-level income. Autologous techniques were more often used in patients who received both reconstruction and radiation (OR, 1.8; P < .001) and less frequently used in patients with capitated insurance (OR, 0.7; P < .001), patients undergoing bilateral mastectomy (OR, 0.5; P < .001), or patients in the highest income quartile (OR, 0.7; P = .006). Delayed reconstruction was performed in 21% of patients who underwent reconstruction. CONCLUSION Breast reconstruction has increased over time, but it has wide geographic variability. Receipt of other treatments correlates with the use of and approaches toward reconstruction. Further research and interventions are needed to ensure equitable access to this important component of multidisciplinary treatment of breast cancer.
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Research Support, Non-U.S. Gov't |
11 |
347 |
6
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Walker GV, Grant SR, Guadagnolo BA, Hoffman KE, Smith BD, Koshy M, Allen PK, Mahmood U. Disparities in stage at diagnosis, treatment, and survival in nonelderly adult patients with cancer according to insurance status. J Clin Oncol 2014; 32:3118-25. [PMID: 25092774 PMCID: PMC4876335 DOI: 10.1200/jco.2014.55.6258] [Citation(s) in RCA: 239] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
PURPOSE The purpose of this study was to determine the association of insurance status with disease stage at presentation, treatment, and survival among the top 10 most deadly cancers using the SEER database. PATIENTS AND METHODS A total of 473,722 patients age 18 to 64 years who were diagnosed with one of the 10 most deadly cancers in the SEER database from 2007 to 2010 were analyzed. A Cox proportional hazards model was used for multivariable analyses to assess the effect of patient and tumor characteristics on cause-specific death. RESULTS Overall, patients with non-Medicaid insurance were less likely to present with distant disease (16.9%) than those with Medicaid coverage (29.1%) or without insurance coverage (34.7%; P < .001). Patients with non-Medicaid insurance were more likely to receive cancer-directed surgery and/or radiation therapy (79.6%) compared with those with Medicaid coverage (67.9%) or without insurance coverage (62.1%; P < .001). In a Cox regression that adjusted for age, race, sex, marital status, residence, percent of county below federal poverty level, site, stage, and receipt of cancer-directed surgery and/or radiation therapy, patients were more likely to die as a result of their disease if they had Medicaid coverage (hazard ratio [HR], 1.44; 95% CI, 1.41 to 1.47; P < .001) or no insurance (HR, 1.47; 95% CI, 1.42 to 1.51; P < .001) compared with non-Medicaid insurance. CONCLUSION Among patients with the 10 most deadly cancers, those with Medicaid coverage or without insurance were more likely to present with advanced disease, were less likely to receive cancer-directed surgery and/or radiation therapy, and experienced worse survival.
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research-article |
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239 |
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Smith GL, Smith BD, Buchholz TA, Giordano SH, Garden AS, Woodward WA, Krumholz HM, Weber RS, Ang KK, Rosenthal DI. Cerebrovascular disease risk in older head and neck cancer patients after radiotherapy. J Clin Oncol 2008; 26:5119-25. [PMID: 18725647 PMCID: PMC4879715 DOI: 10.1200/jco.2008.16.6546] [Citation(s) in RCA: 215] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
PURPOSE Cerebrovascular disease is common in head and neck cancer patients, but it is unknown whether radiotherapy increases the cerebrovascular disease risk in this population. PATIENTS AND METHODS We identified 6,862 patients (age > 65 years) from the Surveillance, Epidemiology, and End Results (SEER) -Medicare cohort diagnosed with nonmetastatic head and neck cancer between 1992 and 2002. Using proportional hazards regression, we compared risk of cerebrovascular events (stroke, carotid revascularization, or stroke death) after treatment with radiotherapy alone, surgery plus radiotherapy, or surgery alone. To further validate whether treatment groups had equivalent baseline risk of vascular disease, we compared the risks of developing a control diagnosis, cardiac events (myocardial infarction, percutaneous coronary intervention, coronary artery bypass graft, or cardiac death). Unlike cerebrovascular risk, no difference in cardiac risk was hypothesized. RESULTS Mean age was 76 +/- 7 years. Ten-year incidence of cerebrovascular events was 34% in patients treated with radiotherapy alone compared with 25% in patients treated with surgery plus radiotherapy and 26% in patients treated with surgery alone (P < .001). After adjusting for covariates, patients treated with radiotherapy alone had increased cerebrovascular risk compared with surgery plus radiotherapy (hazard ratio [HR] = 1.42; 95% CI, 1.14 to 1.77) and surgery alone (HR = 1.50; 95% CI, 1.18 to 1.90). However, no difference was found for surgery plus radiotherapy versus surgery alone (P = .60). As expected, patients treated with radiotherapy alone had no increased cardiac risk compared with the other treatment groups (P = .63 and P = .81). CONCLUSION Definitive radiotherapy for head and neck cancer, but not postoperative radiotherapy, was associated with excess cerebrovascular disease risk in older patients.
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other |
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215 |
8
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Im AP, Sehgal AR, Carroll MP, Smith BD, Tefferi A, Johnson DE, Boyiadzis M. DNMT3A and IDH mutations in acute myeloid leukemia and other myeloid malignancies: associations with prognosis and potential treatment strategies. Leukemia 2014; 28:1774-83. [PMID: 24699305 DOI: 10.1038/leu.2014.124] [Citation(s) in RCA: 210] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Revised: 03/05/2014] [Accepted: 03/25/2014] [Indexed: 02/08/2023]
Abstract
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.
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Review |
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210 |
9
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Gross CP, Smith BD, Wolf E, Andersen M. Racial disparities in cancer therapy: did the gap narrow between 1992 and 2002? Cancer 2008; 112:900-8. [PMID: 18181101 DOI: 10.1002/cncr.23228] [Citation(s) in RCA: 206] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND The purpose of this study was to determine whether racial disparities in cancer therapy had diminished since the time they were initially documented in the early 1990s. METHODS The authors identified a cohort of patients in the SEER-Medicare linked database who were ages 66 to 85 years and who had a primary diagnosis of colorectal, breast, lung, or prostate cancer during 1992 through 2002. The authors identified 7 stage-specific processes of cancer therapy by using Medicare claims. Candidate covariates in multivariate logistic regression included year, clinical, and sociodemographic characteristics, and physician access before cancer diagnosis. RESULTS During the full study period, black patients were significantly less likely than white patients to receive therapy for cancers of the lung (surgical resection of early stage, 64.0% vs 78.5% for blacks and whites, respectively), breast (radiation after lumpectomy, 77.8% vs 85.8%), colon (adjuvant therapy for stage III, 52.1% vs 64.1%), and prostate (definitive therapy for early stage, 72.4% vs 77.2%, respectively). For both black and white patients, there was little or no improvement in the proportion of patients receiving therapy for most cancer therapies studied, and there was no decrease in the magnitude of any of these racial disparities between 1992 and 2002. Racial disparities persisted even after restricting the analysis to patients who had physician access before their diagnosis. CONCLUSIONS There has been little improvement in either the overall proportion of Medicare beneficiaries receiving cancer therapies or the magnitude of racial disparity. Efforts in the last decade to mitigate cancer therapy disparities appear to have been unsuccessful.
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Research Support, Non-U.S. Gov't |
17 |
206 |
10
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Smith BD, Martin GR, Miller EJ, Dorfman A, Swarm R. Nature of the collagen synthesized by a transplanted chondrosarcoma. Arch Biochem Biophys 1975; 166:181-6. [PMID: 1122133 DOI: 10.1016/0003-9861(75)90378-1] [Citation(s) in RCA: 204] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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50 |
204 |
11
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Shaitelman SF, Schlembach PJ, Arzu I, Ballo M, Bloom ES, Buchholz D, Chronowski GM, Dvorak T, Grade E, Hoffman KE, Kelly P, Ludwig M, Perkins GH, Reed V, Shah S, Stauder MC, Strom EA, Tereffe W, Woodward WA, Ensor J, Baumann D, Thompson AM, Amaya D, Davis T, Guerra W, Hamblin L, Hortobagyi G, Hunt KK, Buchholz TA, Smith BD. Acute and Short-term Toxic Effects of Conventionally Fractionated vs Hypofractionated Whole-Breast Irradiation: A Randomized Clinical Trial. JAMA Oncol 2016; 1:931-41. [PMID: 26247543 DOI: 10.1001/jamaoncol.2015.2666] [Citation(s) in RCA: 202] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
IMPORTANCE The most appropriate dose fractionation for whole-breast irradiation (WBI) remains uncertain. OBJECTIVE To assess acute and 6-month toxic effects and quality of life (QOL) with conventionally fractionated WBI (CF-WBI) vs hypofractionated WBI (HF-WBI). DESIGN, SETTING, AND PARTICIPANTS Unblinded randomized trial of CF-WBI (n = 149; 50.00 Gy/25 fractions + boost [10.00-14.00 Gy/5-7 fractions]) vs HF-WBI (n = 138; 42.56 Gy/16 fractions + boost [10.00-12.50 Gy/4-5 fractions]) following breast-conserving surgery administered in community-based and academic cancer centers to 287 women 40 years or older with stage 0 to II breast cancer for whom WBI without addition of a third field was recommended; 76% of study participants (n = 217) were overweight or obese. Patients were enrolled from February 2011 through February 2014 and observed for a minimum of 6 months. INTERVENTIONS Administration of CF-WBI or HF-WBI. MAIN OUTCOMES AND MEASURES Physician-reported acute and 6-month toxic effects using National Cancer Institute Common Toxicity Criteria, and patient-reported QOL using the Functional Assessment of Cancer Therapy for Patients with Breast Cancer (FACT-B). All analyses were intention to treat, with outcomes compared using the χ2 test, Cochran-Armitage test, and ordinal logistic regression. RESULTS Of 287 participants, 149 were randomized to CF-WBI and 138 to HF-WBI. Treatment arms were well matched for baseline characteristics, including FACT-B total score (HF-WBI, 120.1 vs CF-WBI, 118.8; P = .46) and individual QOL items such as somewhat or more lack of energy (HF-WBI, 38% vs CF-WBI, 39%; P = .86) and somewhat or more trouble meeting family needs (HF-WBI, 10% vs CF-WBI, 14%; P = .54). Maximum physician-reported acute dermatitis (36% vs 69%; P < .001), pruritus (54% vs 81%; P < .001), breast pain (55% vs 74%; P = .001), hyperpigmentation (9% vs 20%; P = .002), and fatigue (9% vs 17%; P = .02) during irradiation were lower in patients randomized to HF-WBI. The rate of overall grade 2 or higher acute toxic effects was less with HF-WBI than with CF-WBI (47% vs 78%; P < .001). Six months after irradiation, physicians reported less fatigue in patients randomized to HF-WBI (0% vs 6%; P = .01), and patients randomized to HF-WBI reported less lack of energy (23% vs 39%; P < .001) and less trouble meeting family needs (3% vs 9%; P = .01). Multivariable regression confirmed the superiority of HF-WBI in terms of patient-reported lack of energy (odds ratio [OR], 0.39; 95% CI, 0.24-0.63) and trouble meeting family needs (OR, 0.34; 95% CI, 0.16-0.75). CONCLUSIONS AND RELEVANCE Treatment with HF-WBI appears to yield lower rates of acute toxic effects than CF-WBI as well as less fatigue and less trouble meeting family needs 6 months after completing radiation therapy. These findings should be communicated to patients as part of shared decision making. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT01266642.
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Research Support, Non-U.S. Gov't |
9 |
202 |
12
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Shirvani SM, Jiang J, Chang JY, Welsh JW, Gomez DR, Swisher S, Buchholz TA, Smith BD. Comparative effectiveness of 5 treatment strategies for early-stage non-small cell lung cancer in the elderly. Int J Radiat Oncol Biol Phys 2012; 84:1060-70. [PMID: 22975611 DOI: 10.1016/j.ijrobp.2012.07.2354] [Citation(s) in RCA: 200] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Revised: 07/03/2012] [Accepted: 07/15/2012] [Indexed: 12/31/2022]
Abstract
PURPOSE The incidence of early-stage non-small cell lung cancer (NSCLC) among older adults is expected to increase because of demographic trends and computed tomography-based screening; yet, optimal treatment in the elderly remains controversial. Using the Surveillance, Epidemiology, and End Results (SEER)-Medicare cohort spanning 2001-2007, we compared survival outcomes associated with 5 strategies used in contemporary practice: lobectomy, sublobar resection, conventional radiation therapy, stereotactic ablative radiation therapy (SABR), and observation. METHODS AND MATERIALS Treatment strategy and covariates were determined in 10,923 patients aged ≥ 66 years with stage IA-IB NSCLC. Cox regression, adjusted for patient and tumor factors, compared overall and disease-specific survival for the 5 strategies. In a second exploratory analysis, propensity-score matching was used for comparison of SABR with other options. RESULTS The median age was 75 years, and 29% had moderate to severe comorbidities. Treatment distribution was lobectomy (59%), sublobar resection (11.7%), conventional radiation (14.8%), observation (12.6%), and SABR (1.1%). In Cox regression analysis with a median follow-up time of 3.2 years, SABR was associated with the lowest risk of death within 6 months of diagnosis (hazard ratio [HR] 0.48; 95% confidence interval [CI] 0.38-0.63; referent is lobectomy). After 6 months, lobectomy was associated with the best overall and disease-specific survival. In the propensity-score matched analysis, survival after SABR was similar to that after lobectomy (HR 0.71; 95% CI 0.45-1.12; referent is SABR). Conventional radiation and observation were associated with poor outcomes in all analyses. CONCLUSIONS In this population-based experience, lobectomy was associated with the best long-term outcomes in fit elderly patients with early-stage NSCLC. Exploratory analysis of SABR early adopters suggests efficacy comparable with that of surgery in select populations. Evaluation of these therapies in randomized trials is urgently needed.
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Research Support, U.S. Gov't, Non-P.H.S. |
13 |
200 |
13
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Shirvani SM, Jiang J, Chang JY, Welsh J, Likhacheva A, Buchholz TA, Swisher SG, Smith BD. Lobectomy, sublobar resection, and stereotactic ablative radiotherapy for early-stage non-small cell lung cancers in the elderly. JAMA Surg 2015; 149:1244-53. [PMID: 25321323 DOI: 10.1001/jamasurg.2014.556] [Citation(s) in RCA: 189] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
IMPORTANCE The incidence of early-stage non-small cell lung cancer (NSCLC) among the elderly is expected to rise dramatically owing to demographic trends and increased computed tomographic screening. However, to our knowledge, no modern trials have compared the most common treatments for NSCLC. OBJECTIVE To determine clinical characteristics and survival outcomes associated with the 3 most commonly used definitive therapies for early-stage NSCLC in the elderly. DESIGN, SETTING, AND PARTICIPANTS The Surveillance, Epidemiology, and End Results database linked to Medicare was used to determine the baseline characteristics and outcomes of 9093 patients with early-stage, node-negative NSCLC who underwent definitive treatment consisting of lobectomy, sublobar resection, or stereotactic ablative radiotherapy (SABR) from January 1, 2003, through December 31, 2009. MAIN OUTCOMES AND MEASURES Overall and lung cancer-specific survival were compared using Medicare claims through December 31, 2012. We used proportional hazards regression and propensity score matching to adjust outcomes for key patient, tumor, and practice environment factors. RESULTS The median age was 75 years, and treatment distribution was 79.3% for lobectomy, 16.5% for sublobar resection, and 4.2% for SABR. Unadjusted 90-day mortality was highest for lobectomy (4.0%) followed by sublobar resection (3.7%; P = .79) and SABR (1.3%; P = .008). At 3 years, unadjusted mortality was lowest for lobectomy (25.0%), followed by sublobar resection (35.3%; P < .001) and SABR (45.1%; P < .001). Proportional hazards regression demonstrated that sublobar resection was associated with worse overall survival (adjusted hazard ratio [AHR], 1.32 [95% CI, 1.20-1.44]; P < .001) and lung cancer-specific survival (AHR, 1.50 [95% CI, 1.29-1.75]; P < .001) compared with lobectomy. Propensity score-matching analysis reiterated these findings for overall survival (AHR, 1.36 [95% CI, 1.17-1.58]; P < .001) and lung cancer-specific survival (AHR, 1.46 [95% CI, 1.13-1.90]; P = .004). In proportional hazards regression, SABR was associated with better overall survival than lobectomy in the first 6 months after diagnosis (AHR, 0.45 [95% CI, 0.27-0.75]; P < .001) but worse survival thereafter (AHR, 1.66 [95% CI, 1.39-1.99]; P < .001). Propensity score-matching analysis of well-matched SABR and lobectomy cohorts demonstrated similar overall survival in both groups (AHR, 1.01 [95% CI, 0.74-1.38]; P = .94). CONCLUSIONS AND RELEVANCE Lobectomy was associated with better outcomes than sublobar resection in elderly patients with early-stage NSCLC. Propensity score matching suggests that SABR may be a good option among patients with very advanced age and multiple comorbidities.
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Research Support, U.S. Gov't, Non-P.H.S. |
10 |
189 |
14
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Brodsky RA, Petri M, Smith BD, Seifter EJ, Spivak JL, Styler M, Dang CV, Brodsky I, Jones RJ. Immunoablative high-dose cyclophosphamide without stem-cell rescue for refractory, severe autoimmune disease. Ann Intern Med 1998; 129:1031-5. [PMID: 9867758 DOI: 10.7326/0003-4819-129-12-199812150-00007] [Citation(s) in RCA: 188] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Immunoablative high-dose cyclophosphamide without stem-cell rescue induces durable, complete remission in most patients with aplastic anemia. OBJECTIVE To determine the efficacy of high-dose cyclophosphamide in various refractory, severe autoimmune diseases. DESIGN Prospective phase II study. SETTING Johns Hopkins University (Baltimore, Maryland) and Hahnemann University (Philadelphia, Pennsylvania). PATIENTS Eight patients with refractory, severe autoimmune disease. INTERVENTION Immunoablative high-dose cyclophosphamide (50 mg/kg of body weight per day) for 4 consecutive days. MEASUREMENTS Clinical and laboratory variables of autoimmune disease. RESULTS Seven patients improved markedly: Five achieved complete remission and two achieved partial remission. Four patients have remained in continuous complete remission for 3 to 21 months, and two patients in partial remission continue to improve after 14 and 19 months of follow-up. High-dose cyclophosphamide was well tolerated; median times to a neutrophil count of 0.5 x 10(9) cells/L and platelet transfusion independence were 17 and 16 days, respectively. CONCLUSIONS Immunoablative high-dose cyclophosphamide without stem-cell rescue can induce complete remission in patients with refractory, severe autoimmune disease. Reemergence of marrow function is similar to that seen after autologous transplantation and does not carry the risk for reinfusion of autoaggressive lymphocytes with the autograft.
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Case Reports |
27 |
188 |
15
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Smith BD, Smith GL, Carter D, Sasaki CT, Haffty BG. Prognostic significance of vascular endothelial growth factor protein levels in oral and oropharyngeal squamous cell carcinoma. J Clin Oncol 2000; 18:2046-52. [PMID: 10811669 DOI: 10.1200/jco.2000.18.10.2046] [Citation(s) in RCA: 174] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
PURPOSE Vascular Endothelial Growth Factor (VEGF) promotes angiogenesis in many different tumor types. VEGF levels may affect tumor growth, metastatic potential, and response to radiotherapy. This study assesses the prognostic value of VEGF protein levels in a cohort of patients with oral and oropharyngeal squamous cell carcinomas. The relationships between clinical outcome and the covariables of tumor-node-metastasis stage, disease stage (I to IV), grade, margin status, race, sex, and age were also determined. PATIENTS AND METHODS Chart review identified 77 patients with oral or oropharyngeal squamous cell carcinoma treated with gross total surgical resection and postoperative radiation between 1981 and 1992. Sufficient follow-up data and tumor tissue were available in 56 patients (73%). VEGF protein levels were determined using immunohistochemistry. The association between VEGF status, covariables, and outcome was assessed in a bivariate and multivariate model using two-sided statistical tests. RESULTS Twenty-three tumors (41%) were positive for VEGF expression. VEGF-positive tumors were more likely to recur locally (relative risk [RR] = 3.08; 95% confidence interval [CI], 1.03 to 9.24) and distantly (RR = 4.62; 95% CI, 1.41 to 15.10). In bivariate analysis, VEGF positivity was the most significant predictor of poor disease-free survival (RR = 2.66; 95% CI, 1.27 to 5.56) and overall survival (RR = 3.21; 95% CI, 1.63 to 6.32). In multivariate analysis, VEGF positivity was the most significant predictor of poor disease-free survival (RR = 2.75; 95% CI, 1.30 to 5.79) and overall survival (RR = 3.53; 95% CI, 1.75 to 7.13). CONCLUSION In this cohort, VEGF positivity was the most significant predictor of poor prognosis. VEGF status may prove to be an important prognostic factor in head and neck cancer.
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Goldstein RH, Poliks CF, Pilch PF, Smith BD, Fine A. Stimulation of collagen formation by insulin and insulin-like growth factor I in cultures of human lung fibroblasts. Endocrinology 1989; 124:964-70. [PMID: 2463909 DOI: 10.1210/endo-124-2-964] [Citation(s) in RCA: 173] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
We examined the effects of insulin and insulin-like growth factor I (IGF-I) on the production of collagen by cultures of human embryonic lung fibroblasts. Insulin at 20 ng/ml increased collagen accumulation by 58% and total protein formation by 18%. At 2 micrograms/ml, insulin increased collagen production by 2- to 3-fold and total protein production by 2-fold. The mRNA levels for alpha 1(I) and alpha 1(III) collagen chains were elevated by insulin compared with untreated control values. IGF-I at 10 ng/ml increased collagen production 2-fold. IGF-I at 100 ng/ml maximally increased collagen production 3-fold. A specific antibody to the IGF-I receptor (alpha IR-3) caused a concentration-related decline in insulin-induced collagen formation. The addition of antibody at 1 micrograms/ml, resulted in 80% inhibition of insulin-induced collagen accumulation. Higher levels of antibody were required to inhibit IGF-I mediated collagen formation. The presence of antibody (alpha IR-3) also blocked fibroblast proliferation stimulated by epidermal growth factor plus insulin. These data show that insulin-induced collagen formation is mediated primarily through an interaction with the IGF-I receptor. The modulation of extracellular matrix production by insulin may influence the repair of tissue injury and the development of the accelerated atherosclerosis that accompanies the diabetic state in humans.
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Chavez-MacGregor M, Zhang N, Buchholz TA, Zhang Y, Niu J, Elting L, Smith BD, Hortobagyi GN, Giordano SH. Trastuzumab-related cardiotoxicity among older patients with breast cancer. J Clin Oncol 2013; 31:4222-8. [PMID: 24127446 DOI: 10.1200/jco.2013.48.7884] [Citation(s) in RCA: 170] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
PURPOSE The use of trastuzumab in the adjuvant setting improves outcomes but is associated with cardiotoxicity manifested as congestive heart failure (CHF). The rates and risk factors associated with trastuzumab-related CHF among older patients are unknown. PATIENTS AND METHODS Breast cancer patients at least 66 years old with full Medicare coverage, diagnosed with stage I-III breast cancer between 2005 and 2009, and treated with chemotherapy were identified in the SEER-Medicare and in the Texas Cancer Registry-Medicare databases. The rates and risk factors associated with CHF were evaluated. Chemotherapy, trastuzumab use, comorbidities, and CHF were identified using International Classification of Diseases, version 9, and Healthcare Common Procedure Coding System codes. Analyses included descriptive statistics and Cox proportional hazards models. RESULTS In total, 9,535 patients were included, of whom 2,203 (23.1%) received trastuzumab. Median age of the entire cohort was 71 years old. Among trastuzumab users, the rate of CHF was 29.4% compared with 18.9% in nontrastuzumab users (P < .001). Trastuzumab users were more likely to develop CHF than nontrastuzumab users (hazard ratio [HR], 1.95; 95% CI, 1.75 to 2.17). Among trastuzumab-treated patients, older age (age > 80 years; HR, 1.53; 95% CI, 1.16 to 2.10), coronary artery disease (HR, 1.82; 95% CI, 1.34 to 2.48), hypertension (HR, 1.24; 95% CI, 1.02 to 1.50), and weekly trastuzumab administration (HR, 1.33; 95% CI, 1.05 to 1.68) increased the risk of CHF. CONCLUSION In this large cohort of older breast cancer patients, the rates of trastuzumb-related CHF are higher than those reported in clinical trials. Among patients treated with trastuzumab, those with cardiac comorbidities and older age may be at higher risk. Further studies need to confirm the role that the frequency of administration plays in the development of trastuzumab-related CHF.
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Research Support, Non-U.S. Gov't |
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Mahoney JM, Beatty AM, Smith BD. Selective recognition of an alkali halide contact ion-pair. J Am Chem Soc 2001; 123:5847-8. [PMID: 11403637 DOI: 10.1021/ja0156082] [Citation(s) in RCA: 168] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Ludmir EB, Mainwaring W, Lin TA, Miller AB, Jethanandani A, Espinoza AF, Mandel JJ, Lin SH, Smith BD, Smith GL, VanderWalde NA, Minsky BD, Koong AC, Stinchcombe TE, Jagsi R, Gomez DR, Thomas CR, Fuller CD. Factors Associated With Age Disparities Among Cancer Clinical Trial Participants. JAMA Oncol 2021; 5:1769-1773. [PMID: 31158272 DOI: 10.1001/jamaoncol.2019.2055] [Citation(s) in RCA: 159] [Impact Index Per Article: 39.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Importance Seminal investigation 2 decades ago alerted the oncology community to age disparities in participation in cooperative group trials; less is known about whether these disparities persist in industry-funded research. Objective To characterize the age disparities among trial enrollees on randomized clinical trials (RCTs) of common cancers in clinical oncology and identify factors associated with wider age imbalances. Data Sources Phase 3 clinical oncology RCTs were identified through ClinicalTrials.gov. Study Selection Multiarm RCTs assessing a therapeutic intervention for patients with breast, prostate, colorectal, or lung cancer (the 4 most common cancer disease sites) were included. Data Extraction and Synthesis Trial data were extracted from ClinicalTrials.gov. Trial screening and parameter identification were independently performed by 2 individuals. Data were analyzed in 2018. Main Outcomes and Measures The difference in median age (DMA) between the trial participant median age and the population-based disease-site-specific median age was determined for each trial. Results Three hundred two trials met inclusion criteria. The trials collectively enrolled 262 354 participants; 249 trials (82.5%) were industry-funded. For all trials, the trial median age of trial participants was a mean of 6.49 years younger than the population median age (95% CI, -7.17 to -5.81 years; P < .001). Age disparities were heightened among industry-funded trials compared with non-industry-funded trials (mean DMA, -6.84 vs -4.72 years; P = .002). Enrollment criteria restrictions based on performance status or age cutoffs were associated with age disparities; however, industry-funded trials were not more likely to use these enrollment restrictions than non-industry-funded trials. Age disparities were also larger among trials that evaluated a targeted systemic therapy and among lung cancer trials. Linear regression modeling revealed a widening gap between trial and population median ages over time at a rate of -0.19 years annually (95% CI, -0.37 to -0.01 years; P = .04). Conclusions and Relevance Age disparities between trial participants and the incident disease population are pervasive across trials and appear to be increasing over time. Industry sponsorship of trials is associated with heightened age imbalances among trial participants. With an increasing role of industry funding among cancer trials, efforts to understand and address age disparities are necessary to ensure generalizability of trial results as well as equity in trial access.
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Stewart GW, Amess JA, Eber SW, Kingswood C, Lane PA, Smith BD, Mentzer WC. Thrombo-embolic disease after splenectomy for hereditary stomatocytosis. Br J Haematol 1996; 93:303-10. [PMID: 8639421 DOI: 10.1046/j.1365-2141.1996.4881033.x] [Citation(s) in RCA: 158] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Nine cases of hereditary stomatocytosis (HSt) are presented which show documented thrombotic complications after splenectomy. In three cases, patients became severely ill with pulmonary hypertension and a fourth developed portal hypertension. One unsplenectomized affected adult relative had suspected but unconfirmed thrombotic pathology; the six other affected unsplenectomized adults did not. Since splenectomy is of only limited therapeutic benefit in stomatocytosis, it should not be performed without careful consideration. A tendency to iron overload, even without hypertransfusion and irrespective of splenectomy, is evident in many of these patients.
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Levis M, Tse KF, Smith BD, Garrett E, Small D. A FLT3 tyrosine kinase inhibitor is selectively cytotoxic to acute myeloid leukemia blasts harboring FLT3 internal tandem duplication mutations. Blood 2001; 98:885-7. [PMID: 11468194 DOI: 10.1182/blood.v98.3.885] [Citation(s) in RCA: 158] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Internal tandem duplication (ITD) mutations of the receptor tyrosine kinase FLT3 have been found in 20% to 30% of patients with acute myeloid leukemia (AML). These mutations constitutively activate the receptor and appear to be associated with a poor prognosis. Recent evidence that this constitutive activation is leukemogenic renders this receptor a potential target for specific therapy. In this study, dose-response cytotoxic assays were performed with AG1295, a tyrosine kinase inhibitor active against FLT3, on primary blasts from patients with AML. For each patient sample, the degree of cytotoxicity induced by AG1295 was compared to the response to cytosine arabinoside (Ara C) and correlated with the presence or absence of a FLT3/ITD mutation. AG1295 was specifically cytotoxic to AML blasts harboring FLT3/ITD mutations. The results suggest that these mutations contribute to the leukemic process and that the FLT3 receptor represents a therapeutic target in AML. (Blood. 2001;98:885-887)
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Marsh JC, D'Aunno TA, Smith BD. Increasing access and providing social services to improve drug abuse treatment for women with children. Addiction 2000; 95:1237-47. [PMID: 11092071 DOI: 10.1046/j.1360-0443.2000.958123710.x] [Citation(s) in RCA: 150] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIMS To assess the impact of a substance abuse treatment program for women with children designed to increase access to treatment through transportation, outreach and child-care services. Also, to assess the impact of using access services on the use of other services and on treatment effectiveness. DESIGN A quasi-experimental non-equivalent control group design was used with path analysis to examine the impact of participation in an enhanced services program that provided transportation, outreach and child-care services on the use of other social services and on the use of alcohol and illicit drugs. SETTING Treatment clients were interviewed in-person at enhanced treatment programs and regular substance abuse programs. PARTICIPANTS Study participants included a randomly selected sample of women with children who were clients of the Illinois Department of Children and Family Services. Participants were enrolled in enhanced or regular substance abuse treatment programs. MEASUREMENTS Study participants completed in-person interviews about their characteristics, services use and past and current substance use. FINDINGS Participation in the enhanced program was negatively related to substance use. Further, use of access services was related to use of social services which in turn, was negatively related to substance use. CONCLUSION The study indicates that services that enhance access to treatment and respond to the range of social service needs of women are important for effective substance abuse treatment for women with children.
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Smith BD. Image reconstruction from cone-beam projections: necessary and sufficient conditions and reconstruction methods. IEEE TRANSACTIONS ON MEDICAL IMAGING 1985; 4:14-25. [PMID: 18243947 DOI: 10.1109/tmi.1985.4307689] [Citation(s) in RCA: 145] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Previously unknown sufficient conditions, a necessary condition, and reconstruction methods for image reconstruction from cone-beam projections are developed. A sufficient condition developed is contained in the following statement. Statement 5: If one every plane that intersects the object, there exists at least one cone-beam source point, then the object can be reconstructed. Reconstruction methods for an arbitrary configuration of source points that satisfy Statement 5 are derived. By requiring additional conditions on the configuration of source points, a more efficient reconstruction method is developed. It is shown that when the configuration of source points is a circle, Statement 5 is not satisfied. In spite of this, several suggestions are made for reconstruction from a circle of source points.
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Tadros AB, Yang WT, Krishnamurthy S, Rauch GM, Smith BD, Valero V, Black DM, Lucci A, Caudle AS, DeSnyder SM, Teshome M, Barcenas CH, Miggins M, Adrada BE, Moseley T, Hwang RF, Hunt KK, Kuerer HM. Identification of Patients With Documented Pathologic Complete Response in the Breast After Neoadjuvant Chemotherapy for Omission of Axillary Surgery. JAMA Surg 2017; 152:665-670. [PMID: 28423171 DOI: 10.1001/jamasurg.2017.0562] [Citation(s) in RCA: 142] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Importance A pathologic complete response (pCR; no invasive or in situ cancer) occurs in 40% to 50% of patients with HER2-positive (HER2+) and triple-negative (TN) breast cancer. The need for surgery if percutaneous biopsy of the breast after neoadjuvant chemotherapy (NCT) indicates pCR in the breast (hereinafter referred to as breast pCR) has been questioned, and appropriate management of the axilla in such patients is unknown. Objective To identify patients among exceptional responders to NCT with a low risk for axillary metastases when breast pCR is documented who may be eligible for an omission of surgery clinical trial design. Design, Setting, and Participants This prospective cohort study at a single-institution academic national comprehensive cancer center included 527 consecutive patients with HER2+/TN (T1/T2 and N0/N1) cancer treated with NCT followed by standard breast and nodal surgery from January 1, 2010, through December 31, 2014. Main Outcomes and Measures Patients who achieved a breast pCR were compared with patients who did not based on subtype, initial ultrasonographic findings, and documented pathologic nodal status. Incidence of positive findings for nodal disease on final pathologic review was calculated for patients with and without pCR and compared using relative risk ratios with 95% CIs. Results The analysis included 527 patients (median age, 51 [range, 23-84] years). Among 290 patients with initial nodal ultrasonography showing N0 disease, 116 (40.4%) had a breast pCR and 100% had no evidence of axillary lymph node metastases after NCT. Among 237 patients with initial biopsy-proved N1 disease, 69 of 77 (89.6%) with and 68 of 160 (42.5%) without a breast pCR had no evidence of residual nodal disease (P < .01). Patients without a breast pCR had a relative risk for positive nodal metastases of 7.4 (95% CI, 3.7-14.8; P < .001) compared with those with a breast pCR. Conclusions and Relevance Breast pCR is highly correlated with nodal status after NCT, and the risk for missing nodal metastases without axillary surgery in this cohort is extremely low. These data provide the fundamental basis and rationale for management of the axilla in clinical trials of omission of cancer surgery when image-guided biopsy indicates a breast pCR.
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Research Support, N.I.H., Extramural |
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Zhang ZY, Smith BD. High-generation polycationic dendrimers are unusually effective at disrupting anionic vesicles: membrane bending model. Bioconjug Chem 2000; 11:805-14. [PMID: 11087328 DOI: 10.1021/bc000018z] [Citation(s) in RCA: 141] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The membrane disruption properties of high generation (G4 to G7) poly(amidoamine) (PAMAM) dendrimers are evaluated and compared to linear poly(lysine). The G6 and G7 dendrimers are unusually effective at inducing leaky fusion of anionic, large unilamellar vesicles, as determined by standard fluorescence assays for lipid mixing, leakage, and contents mixing. Both G7 dendrimer and poly(lysine) are able to disrupt sterically stabilized vesicles that are coated with poly(ethylene glycol). A G7 dendrimer/DNA complex with a 1:1 concentration ratio of dendrimer surface amines to DNA phosphate groups is unable to induce leakage of 3:7 POPA-PE vesicles; however, extensive leakage is observed when the surface amine to phosphate stoichiometry is >/=3:1. Thus, the DNA/dendrimer complexes that typically induce high levels of cell transfection are also able to induce high levels of vesicle leakage. The G7 dendrimer does not induce membrane phase separation in 3:7 POPA-PE vesicles, but an inverse hexagonal phase is observed by (31)P NMR. The enhanced membrane disruption is interpreted in terms of a membrane bending model. A rigid, polycationic dendrimer sphere uses electrostatic forces to bend a malleable, anionic membrane and induce bilayer packing stresses. This bending model is biomimetic in the sense that protein-induced membrane bending is currently thought to be an important factor in the fusion mechanism of influenza virus.
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