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Biomedical subjects

Donald L Weaver

Publications and source records attributed to Donald L Weaver.

At least 19 recordsLinked to original sources

Detection of occult sentinel lymph node micrometastases by immunohistochemistry in breast cancer. An NSABP protocol B-32 quality assurance study.

BACKGROUND: Occult metastases, by definition, are not detected on initial examination. They may be present on slides but missed during screening or may be present in paraffin embedded tissue blocks and undetected without additional levels. Anticytokeratin immunohistochemistry (CK IHC) enhances detection of occult metastases, particularly micrometastases (> 0.2 mm but not larger than 2.0 mm) or isolated tumor cell clusters (< or = 0.2 mm). This study defines the rate at which pathologists miss metastases on CK IHC of sentinel lymph nodes (SLN). METHODS: CK IHC sections 0.5 and 1.0 mm from the original surface of SLN tissue blocks were screened by pathologists using standard bright field light microscopes (LM) and by supervised computer assisted cell detection (CACD). All blocks were from breast cancer patients, initially classified 'node negative' on review of routinely stained sections from the surface of each block. Cases missed by LM screening but detected by CACD defined false negative screens. RESULTS: Of 236 cases screened, LM detected 34 (14.4%; 95% CI: 9.6-20.2) cases and, in the 202 cases negative by LM, CACD detected an additional 30 (14.9%; 95% CI: 9.6-21.2%) cases with occult metastases. Occult metastases missed by LM screening ranged from 0.01 to 0.1 mm in greatest dimension. The probability of missing an occult metastasis < or = 0.02 mm; < or = 0.05 mm, and < or = 0.10 mm was 75%, 69.2%, and 61.2%, respectively. No occult metastases larger than 0.10 mm were missed by LM screening. CONCLUSIONS: Pathologists screening the CK IHC stained slides may frequently miss detecting metastases < 0.10 mm.

Axilla↗

Selection of tumor-binding ligands in cancer patients with phage display libraries.

Phage display has been used extensively in vitro and in animal models to generate ligands and to identify cancer-relevant targets. We report here the use of phage-display libraries in cancer patients to identify tumor-targeting ligands. Eight patients with stage IV cancer, including breast, melanoma, and pancreas, had phage-displayed random peptide or scFv library (1.6 x 10(8)-1 x 10(11) transducing units/kg) administered i.v.; tumors were excised after 30 minutes; and tumor-homing phage were recovered. In three patients, repeat panning was possible using phage recovered and amplified from that same patient's tumor. No serious side effects, including allergic reactions, were observed with up to three infusions. Patients developed antiphage antibodies that reached a submaximal level within the 10-day protocol window for serial phage administration. Tumor phage were recoverable from all the patients. Using a filter-based ELISA, several clones from a subset of the patients were identified that bound to a tumor from the same patient in which clones were recovered. The clone-binding to tumor was confirmed by immunostaining, bioassay, and real-time PCR-based methods. Binding studies with noncancer and cancer cell lines of the same histology showed specificity of the tumor-binding clones. Analysis of insert sequences of tumor-homing peptide clones showed several motifs, indicating nonrandom accumulation of clones in human tumors. This is the first reported series of cancer patients to receive phage library for serial panning of tumor targeting ligands. The lack of toxicity and the ability to recover clones with favorable characteristics are a first step for further research with this technology in cancer patients.

Amino Acid Sequence↗

Pathologic findings from the Breast Cancer Surveillance Consortium: population-based outcomes in women undergoing biopsy after screening mammography.

BACKGROUND: To the authors' knowledge, a comprehensive analysis of pathology outcomes after screening mammography, as it is practiced clinically in the U.S. general population, has not been performed. METHODS: Breast Cancer Surveillance Consortium data from 1996-2001 were used to identify pathology specimens that were obtained within 1 year of screening mammograms performed on 786,846 women ages 40-89 years. The pathology results were classified as invasive carcinoma, ductal carcinoma in situ (DCIS), or benign. The associations between overall pathology outcomes and invasive tumor size and lymph node status were analyzed by age and mammography assessment category. RESULTS: The rates of both recommending and performing a biopsy varied little with age. The 1,664,032 screening mammograms were followed by 26,748 known biopsies (1.6%) and 8815 diagnoses of breast carcinoma (0.53%). Overall, 81% of carcinomas were invasive, and 78% of those were pathologically lymph node-negative tumors, in contrast to the 66% prevalence observed in the Surveillance, Epidemiology, and End Results (SEER) data during the same period. Most invasive tumors measured between 0 mm and 10 mm (35%) or between 11 mm and 20 mm (36%) in greatest dimension, and 92% and 78% were lymph node-negative tumors, respectively: Biopsy results that were classified as malignant increased with age (P < 0.0001) and were most likely to follow Breast Imaging, Reporting, and Diagnosis System Category 5 and 4 assessments, respectively. Ductal hyperplasia (19.6%), fibroadenoma (18.5%), and other benign findings (56.1%) were the most common benign diagnoses. CONCLUSIONS: Pathologically negative lymph nodes were more prevalent in this mammographically screened population than in the overall SEER population. The prevalence of invasive carcinoma, DCIS, and benign findings presented herein establish a range of expected biopsy outcomes for women after screening mammography in the general U.S. population.

Adult↗

Performance benchmarks for screening mammography.

PURPOSE: To retrospectively evaluate the range of performance outcomes of the radiologist in an audit of screening mammography by using a representative sample of U.S. radiologists to allow development of performance benchmarks for screening mammography. MATERIALS AND METHODS: Institutional review board approval was obtained, and study was HIPAA compliant. Informed consent was or was not obtained according to institutional review board guidelines. Data from 188 mammographic facilities and 807 radiologists obtained between 1996 and 2002 were analyzed from six registries from the Breast Cancer Surveillance Consortium (BCSC). Contributed data included demographic information, clinical findings, mammographic interpretation, and biopsy results. Measurements calculated were positive predictive values (PPVs) from screening mammography (PPV(1)), biopsy recommendation (PPV(2)), biopsy performed (PPV(3)), recall rate, cancer detection rate, mean cancer size, and cancer stage. Radiologist performance data are presented as 50th (median), 10th, 25th, 75th, and 90th percentiles and as graphic presentations by using smoothed curves. RESULTS: There were 2 580 151 screening mammographic studies from 1 117 390 women (age range, <30 to >/=80 years). The respective means and ranges of performance outcomes for the middle 50% of radiologists were as follows: recall rate, 9.8% and 6.4%-13.3%; PPV(1), 4.8% and 3.4%-6.2%; and PPV(2), 24.6% and 18.8%-32.0%. Mean cancer detection rate was 4.7 per 1000, and the median [corrected] mean size of invasive cancers was 13 mm. The range of performance outcomes for the middle 80% of radiologists also was presented. CONCLUSION: Community screening mammographic performance measurements of cancer outcomes for the majority of radiologists in the BCSC surpass performance recommendations. Recall rate for almost half of radiologists, however, is higher than the recommended rate.

Adult↗

The frequency of ipsilateral second tumors after breast-conserving surgery for DCIS: a population based analysis.

BACKGROUND: The diagnosis of ductal carcinoma in situ (DCIS) is increasing, although to the authors' knowledge there is no consensus regarding optimal treatment. This analysis of women treated with breast-conserving surgery (BCS) evaluated the impact of radiation therapy (RT) in patient outcomes. METHODS: The current study included a population-based sample of 1103 women residing in selected Surveillance, Epidemiology, and End Results (SEER) registries who were diagnosed with DCIS between 1991-1992. Data were obtained from the registry, physician follow-up, and pathology reports. Physicians were contacted in 1999 to determine whether the patient had developed a second event in the ipsilateral breast. For second events, pathology reports were reviewed to determine the presence of in situ or invasive disease. Registry data through 2001 were used to assess death rates and cause of death. Cox proportional hazards and logistic regression models were used to evaluate the rates of second events and breast carcinoma deaths between women treated with and without RT. RESULTS: Over an average of 91 months, 13.2% of women developed a second event. Rates of second events were 11% for women treated with BCS and RT compared with 15% for women treated with BCS only (adjusted hazards ratio, 0.64; 95% confidence interval, 0.44-0.92). Women receiving RT were significantly less likely to develop invasive breast carcinoma in the ipsilateral breast (adjusted odds ratio, 0.40). By 2001, the rate of death from breast carcinoma was 2.7%; in the group of women treated with BCS only compared with 0.8% in the group of women treated with BCS with RT. CONCLUSIONS: Among a population-based cohort, RT was found to significantly reduce the risk of second events in the ipsilateral breast, particularly invasive tumors, although not to the extent reported in clinical trials.

Aged↗

American Society of Clinical Oncology guideline recommendations for sentinel lymph node biopsy in early-stage breast cancer.

PURPOSE: To develop a guideline for the use of sentinel node biopsy (SNB) in early stage breast cancer. METHODS: An American Society of Clinical Oncology (ASCO) Expert Panel conducted a systematic review of the literature available through February 2004 on the use of SNB in early-stage breast cancer. The panel developed a guideline for clinicians and patients regarding the appropriate use of a sentinel lymph node identification and sampling procedure from hereon referred to as SNB. The guideline was reviewed by selected experts in the field and the ASCO Health Services Committee and was approved by the ASCO Board of Directors. RESULTS: The literature review identified one published prospective randomized controlled trial in which SNB was compared with axillary lymph node dissection (ALND), four limited meta-analyses, and 69 published single-institution and multicenter trials in which the test performance of SNB was evaluated with respect to the results of ALND (completion axillary dissection). There are currently no data on the effect of SLN biopsy on long-term survival of patients with breast cancer. However, a review of the available evidence demonstrates that, when performed by experienced clinicians, SNB appears to be a safe and acceptably accurate method for identifying early-stage breast cancer without involvement of the axillary lymph nodes. CONCLUSION: SNB is an appropriate initial alternative to routine staging ALND for patients with early-stage breast cancer with clinically negative axillary nodes. Completion ALND remains standard treatment for patients with axillary metastases identified on SNB. Appropriately identified patients with negative results of SNB, when done under the direction of an experienced surgeon, need not have completion ALND. Isolated cancer cells detected by pathologic examination of the SLN with use of specialized techniques are currently of unknown clinical significance. Although such specialized techniques are often used, they are not a required part of SLN evaluation for breast cancer at this time. Data suggest that SNB is associated with less morbidity than ALND, but the comparative effects of these two approaches on tumor recurrence or patient survival are unknown.

Breast Neoplasms↗

The detection of isolated tumor cells in bone marrow comparing bright-field immunocytochemistry and multicolor immunofluorescence.

BACKGROUND: The detection of isolated tumor cells in bone marrow by immunocytochemistry (ICC) has been reported to predict progression of early-stage breast cancer. The most common staining procedure uses bright-field ICC with cytokeratin (CK) antibodies to label isolated tumor cells. However, this method can result in false-positive staining events. We used multicolor immunofluorescence (IF) to develop a more specific assay for detecting isolated tumor cells in marrow samples from breast cancer patients. METHODS: We compared ICC and IF side by side for detection of cancer cells and false-positive staining events on bone marrow aspirates from breast cancer patients, bone marrow from healthy donors, and healthy donor blood spiked with cancer cells. The primary target for isolated tumor cell detection was CK for both methods. IF used an additional set of antibodies to label hematopoietic cells (HCs). RESULTS: The detection rate of CK+ events in breast cancer patient bone marrow aspirates was 18 (58%) of 31 for ICC and 21 (68%) of 31 for IF. However, with IF, 17 of 21 CK+ cases were stained with HC markers and thus were identified as false-positive events. A surprisingly high CK+ event rate was observed in healthy donor blood and marrow. In all healthy donor samples, CK+ events were readily identified as HCs by IF. Detection sensitivity of spiked cancer cells in donor blood was similar for both methods. CONCLUSIONS: There is a high frequency of CK+ events in blood and marrow, and it is important to note that this is observed both in patients with and those without cancer. IF with multiple HC markers allows straightforward discrimination between CK+ cells of hematopoietic and nonhematopoietic origin.

Bone Marrow Examination↗

Predicting biopsy outcome after mammography: what is the likelihood the patient has invasive or in situ breast cancer?

BACKGROUND: As many as 1,000,000 breast biopsies are performed annually in the United States. Although substantial effort has been devoted to estimating breast cancer risk, there have been no studies to predict outcome in women undergoing breast biopsy. METHODS: A population-based study was undertaken to develop and test models for predicting the probability of invasive breast cancer and/or ductal carcinoma-in-situ in 7670 women undergoing breast biopsy after mammography. Logistical prediction models were developed by using data from 6129 randomly selected women and tested with data from the remaining women. RESULTS: The overall cancer prevalence among women undergoing biopsy was 22.4%. Prevalence in women with mammograms highly suggestive of malignancy (category 5) was 84.6%, with minimal variation in individual cancer probabilities due to age. A total of 24.6% of women with suspicious mammograms (category 4) had cancer, but individual probability estimates ranged from .01 to .86, depending on age, presence of a lump, previous biopsy, menopausal status, and use of postmenopausal hormone therapy. These variables also influenced biopsy outcome in women with other mammography assessments (categories 0-3), but the overall prevalence was lower (8.6%), and estimated probabilities ranged from .01 to .45. When cancer was present, the probability of invasive disease was influenced by mammogram assessment category, absence of mammogram calcifications, and presence of a lump. CONCLUSIONS: The probabilities of invasive cancer and ductal carcinoma-in-situ in women undergoing biopsy can be more accurately predicted by using clinical characteristics in addition to mammography findings. This information could potentially influence decisions regarding immediate biopsy or continued surveillance.

Adolescent↗

The effect of tissue fixation and processing on breast cancer size.

Precise measurement of an invasive breast cancer is crucial for pathological staging and subsequent patient management. Formalin fixation and histological processing may change tissue size, but there is no agreement on which state of the specimen, fresh or fixed, should be used for final tumor measurement. To determine the influence of fixation and processing on breast tumor size, a specific 1-dimensional measurement from 50 invasive breast tumors was recorded in fresh, fixed, and processed/mounted states. Tumors varied in maximum measured dimension from 4 to 20 mm and contained 10% to 90% estimated fibrous tissue (mean, 52.8%). In 96% of cases, there was no difference in measured size between fresh and fixed states. After final processing and mounting, a decrease in size from initial fresh measurement was noted in 40% of cases (mean difference, 2.4 mm; maximum difference, 7 mm). In 9 cases (18%), the measured size increased by a maximum of 3 mm (mean, 1.7 mm) after processing/mounting. Twenty-one cases (42%) showed no change in measurement during the entire fixation and processing protocol. Increases in measured size were attributed largely to tissue expansion during histological sectioning/mounting. One can arguably measure the size of an invasive breast cancer from either the fresh or fixed state without affecting accuracy, but caution should be exercised in relying solely on the microscopic measurements.

Adenocarcinoma↗

Prerandomization Surgical Training for the National Surgical Adjuvant Breast and Bowel Project (NSABP) B-32 trial: a randomized phase III clinical trial to compare sentinel node resection to conventional axillary dissection in clinically node-negative breast cancer.

OBJECTIVE: To train surgeons in a standardized technique of sentinel lymph node biopsy and to prepare them for the requirements of a prospective randomized surgical trial. SUMMARY BACKGROUND DATA: The NSABP B32 trial opened to accrual in May 1999. A significant component of this trial was a prerandomization training phase of surgeons performed by a group of core surgical trainers. The goals of this training phase were to expeditiously instruct surgeons in a standardized technique of sentinel lymph node biopsy and to educate those same surgeons in complete and accurate data collection and source documentation for the trial. METHODS: This study is a description of the training data collected in a prospective fashion for the training component for surgeon entry into the B32 trial, evaluating the effectiveness of the training program in regards to surgical outcomes and protocol compliance. RESULTS: Two hundred twenty-six registered surgeons underwent site visit training by a core surgical trainer and 187 completed training and were approved to randomize patients on the trial. The results of 815 training (nontrial) cases demonstrated a technical success rate for identifying sentinel nodes at 96.2% with a false negative rate of 6.7%. A protocol compliance analysis, which included the evaluation of 94 separate fields, showed mean protocol compliance of 98.6% for procedural fields, 95.5% for source documentation fields and 95.0% for data entry fields. CONCLUSIONS: This training and quality control program has resulted in a large number of surgeons capable of performing sentinel lymph node biopsy in a standardized fashion with a high degree of protocol compliance and pathologic accuracy. This will ensure optimal results for procedures performed on the randomized phase of the trial.

Axilla↗

Identification of a small peptide that inhibits the phosphorylation of ErbB2 and proliferation of ErbB2 overexpressing breast cancer cells.

ErbB2 is overexpressed in approximately 30% of breast cancer patients with a correlation to poor prognosis. ErbB2 has been identified as a useful receptor for molecular targeting. A cyclic 20 amino acid phage display random peptide library was constructed using the fUSE5 gene III system. The library was panned against 2 different purified forms of the external domain of ErbB2. This resulted in the identification of several ErbB2-binding phage clones with variable binding to different ErbB2 preparations. One clone (EC-1) bound all preparations of ErbB2 including live cells and fresh frozen human breast cancer specimens. The synthetic peptide based on the deduced sequence of the EC-1 clone and its biotin-conjugated form retained binding affinity for purified ErbB2 and ErbB2 overexpressing cell lysates. EC-1 peptide was able to effectively inhibit the phosphorylation of ErbB2 on residues Y1248 and Y877 in a dose- and time-dependent manner. Furthermore, EC-1 peptide selectively inhibits the proliferation of ErbB2 overexpressing breast cancer cells. The linear portion of the cyclic EC-1 peptide was shown to be essential for binding ErbB2. In addition, 4 biased phage libraries were constructed allowing 4 different regions of the EC-1 peptide to have random sequence. Screening these EC-1 biased libraries did not result in higher affinity peptides but did demonstrate the importance of amino acids at position 1-4 on the N-terminal flanking arm and 11-15 within the cyclic ring. Interestingly, EC-1 contains homologous motifs with known ErbB receptor family ligands. We have identified a small peptide that binds to the extracellular domain of ErbB2, inhibits ErbB2 autophosphorylation and inhibits the proliferation of ErbB2 overexpressing cells. This supports the notion that small peptides can bind to targets important in cancer therapy even if a target does not have a natural ligand. Continuing research with this peptide includes increasing its affinity to ErbB2, evaluation of pharmacokinetics and evaluation of anti-proliferative effects with conjugate anti-cancer agents.

Amino Acid Sequence↗

Effect of breast augmentation on the accuracy of mammography and cancer characteristics.

CONTEXT: Breast augmentation is not associated with an increased risk of breast cancer; however, implants may interfere with the detection of breast cancer thereby delaying cancer diagnosis in women with augmentation. OBJECTIVE: To determine whether mammography accuracy and tumor characteristics are different for women with and without augmentation. DESIGN, SETTING, AND PARTICIPANTS: A prospective cohort of 137 women with augmentation and 685 women without augmentation diagnosed with breast cancer between January 1, 1995, and October 15, 2002, matched (1:5) by age, race/ethnicity, previous mammography screening, and mammography registry, and 10 533 women with augmentation and 974 915 women without augmentation and without breast cancer among 7 mammography registries in Denver, Colo; Lebanon, NH; Albuquerque, NM; Chapel Hill, NC; San Francisco, Calif; Seattle, Wash; and Burlington, Vt. MAIN OUTCOME MEASURES: Comparison between women with and without augmentation of mammography performance measures and cancer characteristics, including invasive carcinoma or ductal carcinoma in situ, tumor stage, nodal status, size, grade, and estrogen-receptor status. RESULTS: Among asymptomatic women, the sensitivity of screening mammography based on the final assessment was lower in women with breast augmentation vs women without (45.0% [95% confidence interval [CI], 29.3%-61.5%] vs 66.8% [95% CI, 60.4%-72.8%]; P =.008), and specificity was slightly higher in women with augmentation (97.7% [95% CI, 97.4%-98.0%] vs 96.7% [95% CI, 96.6%-96.7%]; P<.001). Among symptomatic women, both sensitivity and specificity were lower for women with augmentation compared with women without but these differences were not significant. Tumors were of similar stage, size, estrogen-receptor status, and nodal status but tended to be lower grade (P =.052) for women with breast augmentation vs without. CONCLUSIONS: Breast augmentation decreases the sensitivity of screening mammography among asymptomatic women but does not increase the false-positive rate. Despite the lower accuracy of mammography in women with augmentation, the prognostic characteristics of tumors are not influenced by augmentation.

Adult↗

NSABP-32: Phase III, randomized trial comparing axillary resection with sentinal lymph node dissection: a description of the trial.

The NSABP-32 trial is a randomized, phase III clinical trial to compare sentinel node (SN) resection to conventional axillary dissection in clinically node-negative breast cancer patients. The primary aims of the trial are to determine if removal of only SNs provides survival and regional control equivalent to those of axillary dissection, while diminishing the magnitude of surgically related side effects. In order to ensure consistency of the outcomes for this trial, a standardized method of SN surgery has been utilized for all cases. A secondary aim of the B32 trial is to evaluate whether patients with "occult" metastases in the SNs have worse survival. Accrual is taking place at 73 institutions in North America, and 217 surgeons are enrolling patients.

Axilla↗

Influence of breast cancer histology on the relationship between ultrasound and pathology tumor size measurements.

Establishing an accurate primary invasive breast cancer size is crucial for patient management. Although ultrasonographic measurement is reported to correlate reliably with the gold standard pathology measurement, few authors have examined the influence of histologic subtype on ultrasound measurement. The common subtypes of invasive breast carcinoma, ductal and lobular, have different growth patterns, which may influence the ability of ultrasound to predict pathologic size. For this analysis, ultrasound and pathology reports were retrospectively reviewed for 204 women with 210 invasive breast cancers, including 129 ductal, 41 lobular, and 40 mixed pattern ductal and lobular carcinomas. For each tumor, the largest pathology and ultrasound dimensions were compared using Pearson's correlations, linear regression, paired t-tests and Wilcoxon signed ranks tests, stratified by histologic subtype. The Hodges-Lehmann approach was used to obtain 95% confidence intervals (CI) for median difference of the sizes. Ultrasonography consistently underestimated pathologic tumor size; the overall median difference was 3.5 mm (CI: 2.5-4.0 mm) and for subtypes: 2.5 mm (CI: 1.5-3.5 mm) for ductal pattern; 3.0 mm (CI: 1.5-4.5 mm) for mixed pattern; and in contrast, 7.5 mm (CI: 5.0-13.5 mm) for lobular pattern tumors. Significant correlations of similar magnitude, were observed between size measurements for ductal, lobular, and mixed subtypes (r=0.816, 0.811 and 0.672, respectively; all P<0.001); however, linear regression models differed between subtypes. Although practical and widely available, ultrasonography tends to underestimate pathologic tumor size. The size difference may be large for lobular carcinomas, potentially influencing stage; differences are less pronounced for ductal and mixed subtypes. Pathologic tumor size can be estimated from the ultrasonographic measurement, particularly if the histologic tumor subtype is known. The results of this study underscore the continued benefit of pretreatment tumor histology.

Breast Neoplasms↗

Primary central nervous system posttransplant lymphoproliferative disorders.

Posttransplant lymphoproliferative disorders (PTLDs) represent a spectrum ranging from Epstein-Barr virus (EBV)-driven polyclonal lymphoid proliferations to EBV+ or EBV- malignant lymphomas. Central nervous system (CNS) PTLDs have not been characterized fully. We reviewed the clinical, radiologic, and pathologic features of 12 primary CNS PTLDs to define them more precisely. Patients included 10 males and 2 females (median age, 43.4 years) who were recipients of kidney (n = 5), liver (n = 2), heart (n = 2), peripheral blood stem cells (n = 2), or bone marrow (n = 1). All received immunosuppressive therapy. CNS symptoms developed 3 to 131 months (mean, 31 months) after transplantation. By neuroimaging, most showed multiple (3 to 9) intra-axial, contrast-enhancing lesions. Histologic sections showed marked expansion of perivascular spaces by large, cytologically malignant lymphoid cells that were CD45+, CD20+, EBV+ and showed light chain restriction or immunoglobulin gene rearrangement. In distinction to PTLDs in other organ systems, CNS PTLDs were uniformly high-grade lymphomas that fulfilled the World Health Organization criteria for monomorphic PTLDs. Extremely short survival periods were noted for each CNS PTLD that followed peripheral blood stem cell transplantation. Survival of others with CNS PTLD varied; some lived more than 2 years.

Adult↗

Prognostic characteristics of breast cancer among postmenopausal hormone users in a screened population.

PURPOSE: We determined the risk of breast cancer and tumor characteristics among current postmenopausal hormone therapy users compared with nonusers, by duration of use. METHODS: From January 1996 to December 2000, data were collected prospectively on 374,465 postmenopausal women aged 50 to 79 years who underwent screening mammography. We calculated the relative risk (RR) of breast cancer (invasive or ductal carcinoma-in-situ) and type of breast cancer within 12 months of postmenopausal therapy use among current hormone users with a uterus (proxy for estrogen and progestin use) and without a uterus (proxy for estrogen use), compared with nonusers. RESULTS: Compared with nonusers, women using estrogen and progestin for >/= 5 years were at increased risk of breast tumors of stage 0 or I (RR, 1.51; 95% CI, 1.37 to 1.66), stage II or higher (RR, 1.46; 95% CI, 1.30 to 1.63), size </= 20 mm (RR, 1.59; 95% CI, 1.43 to 1.76), size greater than 20 mm (RR, 1.24; 95% CI, 1.09 to 1.42), grade 1 or 2 (RR, 1.60; 95% CI, 1.44 to 1.77), grade 3 or 4 (RR, 1.54; 95% CI, 1.37 to 1.73), and estrogen receptor-positive (RR, 1.72; 95% CI, 1.55 to 1.90). Estrogen-only users were slightly more likely to have estrogen receptor-positive breast cancer compared with nonusers (RR, 1.14; 95% CI, 1.06 to 1.23). CONCLUSION: Use of estrogen and progestin postmenopausal hormone therapy for five years or more increased the likelihood of developing breast cancer, including both tumors with favorable prognostic features and tumors with unfavorable prognostic features.

Aged↗

Staging system for breast cancer: revisions for the 6th edition of the AJCC Cancer Staging Manual.

Since its inception, the AJCC staging system for breast cancer has been in an almost constant state of evolution, striving with each revision to reflect the most up-to-date clinical research as well as the widespread consensus among physicians about appropriate diagnostic and treatment standards. To date, these revisions have essentially represented a "fine-tuning" of the initial judgment that tumor size, lymph node status, and presence of distant metastases are the most significant prognostic factors for breast cancer. With the problems of standardization and reproducibility being resolved, it is likely that histologic grade will join this group of independent markers and be incorporated into the AJCC staging system in the near future. Over the last 15 years. considerable attention has been focused on the discovery of new markers visualized with immunohistochemistry and RT-PCR that may be validated as independent prognostic indicators (reviewed by Mirza et al). To date, the usefulness of many of these markers has been limited by lack of standardization in measurement techniques, but several show great promise for the future. By increasing the number of prognostic markers that can give independent information about patient outcome, physicians will be better able to determine optimal treatment approaches for individual patients.

Advisory Committees↗