Publications by authors named "Paulo Salazar"

11 Publications

  • Page 1 of 1

Ultrarapid Mutation Screening Followed by Comprehensive Next-Generation Sequencing: A Feasible, Informative Approach for Lung Carcinoma Cytology Specimens With a High Success Rate.

JTO Clin Res Rep 2020 Sep 18;1(3). Epub 2020 Jul 18.

Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, New York.

Introduction: For patients with advanced NSCLC, cytologic samples may be the only diagnostic specimen available for molecular profiling. Although both rapid and comprehensive assessment are essential in this setting, an integrated multitest approach remains an important strategy in many laboratories, despite the risks and challenges when working with scant samples. In this study, we describe our experience and high success rate in using a multitest approach, focusing on the clinical validation and incorporation of ultrarapid testing using the Idylla system followed by comprehensive next-generation sequencing (NGS).

Methods: Cytology samples received for routine molecular testing were included in this study. The performance characteristics of the Idylla assay were assessed; tissue suitability parameters and interpretation criteria to supplement automated mutation calling were established. The assay performance was monitored for 1 year, comparing the results with those of concurrent NGS testing by MSK-IMPACT (primarily) or MSK-AmpliSeq and MSK-Fusion solid panel in a subset of cases.

Results: Overall, 301 samples were studied; 83 samples were included in validation (60.2% [50 of 83] were positive for mutations). Concordance with the reference method was 96.4% (80 of 83) of the samples with excellent reproducibility. The limit of detection was variable depending on the total tissue input and the specific mutation tested. Unextracted tissue inputs that maintained total cycle of quantification at less than 23 allowed all mutations to be detected if present at greater than 5% variant allele frequency. Mutations could be detected at 1% variant allele frequency with total cycle of quantification of 18. During the clinical implementation phase, 218 NSCLC samples were tested by Idylla (24.3% [53 of 218] were mutation positive). Concurrent NGS testing was requested on 165 samples and successfully performed on 96.4% (159 of 165) of the samples. The Idylla automated results were concordant with those obtained by NGS in 96.2% (153 of 159) of cases and improved to 98.7% (157 of 159) after incorporation of manual review criteria to supplement automated calling, resulting in a diagnostic sensitivity of 95.6% (95% confidence interval: 84.9%-99.5%). In general, 9% (14 of 159) of the cases tested by NGS had mutations not covered by the Idylla assay, primarily insertions in exon 19 and 20 and minor mutations cooccurring with canonical sensitizing mutations.

Conclusions: Comprehensive molecular testing is feasible and has a high success rate in NSCLC cytology samples when using a multitest approach. Testing with the Idylla system enables rapid and accurate determination of the status without compromising subsequent NGS testing.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jtocrr.2020.100077DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7839984PMC
September 2020

Rapid EGFR Mutation Detection Using the Idylla Platform: Single-Institution Experience of 1200 Cases Analyzed by an In-House Developed Pipeline and Comparison with Concurrent Next-Generation Sequencing Results.

J Mol Diagn 2021 Mar 18;23(3):310-322. Epub 2020 Dec 18.

Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, New York. Electronic address:

Mutations in the epidermal growth factor receptor (EGFR) are the most common targetable alterations in lung adenocarcinoma. To facilitate rapid testing, the Idylla EGFR assay was incorporated as a screening method before next-generation sequencing (NGS). Validation and experience using an in-house developed analysis pipeline, enhanced with a manual review algorithm is described. Results are compared with corresponding NGS results. In all, 1249 samples were studied. Validation demonstrated 98.57% (69/70) concordance with the reference methods. The limit of detection varied from 2% to 5% variant allele frequency for total EGFR quantitation cycle between 20 and 23. Of the 1179 clinical cases, 23.41% were EGFR-positive by Idylla. Concurrent NGS was successfully performed on 94.9% (799/842) requests. Concordance of Idylla with NGS was 98.62% (788/799) and 98.50% (787/799) using our in-house and Idylla analysis pipelines, respectively. Discordances involved missed mutations by both assays associated with low tumor/low input. Incorporating a manual review algorithm to supplement automated calls improved accuracy from 98.62% to 99.37% and sensitivity from 94.68% to 97.58%. Overall reporting time, from receipt of material to official clinical report, ranged from 1 to 3 days. Therefore, Idylla EGFR testing enables rapid and sensitive screening without compromising subsequent comprehensive NGS, when required. Automated calling, enhanced with a manual review algorithm, reduces false-negative calls associated with low tumor/low input samples.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jmoldx.2020.11.009DOI Listing
March 2021

A Pan-Cancer Study of Somatic TERT Promoter Mutations and Amplification in 30,773 Tumors Profiled by Clinical Genomic Sequencing.

J Mol Diagn 2021 Feb 5;23(2):253-263. Epub 2020 Dec 5.

Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, New York. Electronic address:

TERT gene promoter mutations are known in multiple cancer types. Other TERT alterations remain poorly characterized. Sequencing data from 30,773 tumors analyzed by a hybridization capture next-generation sequencing assay (Memorial Sloan Kettering Cancer Center Integrated Mutation Profiling of Actionable Cancer Targets) were analyzed for the presence of TERT alterations. Promoter rearrangements (500 bases upstream of the transcriptional start site), hypermethylation (n = 57), and gene expression (n = 155) were evaluated for a subset of cases. Mutually exclusive and recurrent promoter mutations were identified at three hot spots upstream of the transcriptional start site in 11.3% of cases (-124: 74%; -146: 24%; and -138: <2%). Mutually exclusive amplification events were identified in another 2.3% of cases, whereas mutually exclusive rearrangements proximal to the TERT gene were seen in 24 cases. The highest incidence of TERT promoter mutations was seen in cutaneous melanoma (82%), whereas amplification events significantly outnumbered promoter mutations in well-differentiated/dedifferentiated liposarcoma (14.1% versus 2.4%) and adrenocortical carcinoma (13.6% versus 4.5%). Gene expression analysis suggests that the highest levels of gene expression are seen in cases with amplifications and rearrangements. Hypermethylation events upstream of the TERT coding sequence were not mutually exclusive with known pathogenic alterations. Studies aimed at defining the prevalence and prognostic impact of TERT alterations should incorporate other pathogenic TERT alterations as these may impact telomerase function.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jmoldx.2020.11.003DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7874333PMC
February 2021

TFEB Expression Profiling in Renal Cell Carcinomas: Clinicopathologic Correlations.

Am J Surg Pathol 2019 11;43(11):1445-1461

Departments of Pathology.

TFEB is overexpressed in TFEB-rearranged renal cell carcinomas as well as in renal tumors with amplifications of TFEB at 6p21.1. As recent literature suggests that renal tumors with 6p21.1 amplification behave more aggressively than those with rearrangements of TFEB, we compared relative TFEB gene expression in these tumors. This study included 37 TFEB-altered tumors: 15 6p21.1-amplified and 22 TFEB-rearranged (including 5 cases from The Cancer Genome Atlas data set). TFEB status was verified using a combination of fluorescent in situ hybridization (n=27) or comprehensive molecular profiling (n=13) and digital droplet polymerase chain reaction was used to quantify TFEB mRNA expression in 6p21.1-amplified (n=9) and TFEB-rearranged renal tumors (n=19). These results were correlated with TFEB immunohistochemistry. TFEB-altered tumors had higher TFEB expression when normalized to B2M (mean: 168.9%, n=28), compared with non-TFEB-altered controls (mean: 7%, n=18, P=0.005). Interestingly, TFEB expression in tumors with rearrangements (mean: 224.7%, n=19) was higher compared with 6p21.1-amplified tumors (mean: 51.2%, n=9; P=0.06). Of note, classic biphasic morphology was only seen in TFEB-rearranged tumors and when present correlated with 6.8-fold higher TFEB expression (P=0.00004). Our results suggest that 6p21.1 amplified renal tumors show increased TFEB gene expression but not as much as t(6;11) renal tumors. These findings correlate with the less consistent/diffuse expression of downstream markers of TFEB activation (cathepsin K, melan A, HMB45) seen in the amplified neoplasms. This suggests that the aggressive biological behavior of 6p21.1 amplified renal tumors might be secondary to other genes at the 6p21.1 locus that are co-amplified, such as VEGFA and CCND3, or other genetic alterations.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/PAS.0000000000001307DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6788764PMC
November 2019

Establishment of Immunoglobulin Heavy (IGH) Chain Clonality Testing by Next-Generation Sequencing for Routine Characterization of B-Cell and Plasma Cell Neoplasms.

J Mol Diagn 2019 03 25;21(2):330-342. Epub 2018 Dec 25.

Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York.

Immunoglobulin heavy chain (IGH) clonality testing by next-generation sequencing (NGS) offers unique advantages over current low-throughput methods in the assessment of B-cell lineage neoplasms. Clinical use remains limited because assays are not standardized and validation/implementation guidelines are not yet developed. Herein, we describe our clinical validation and implementation of NGS IGH clonality testing and summarize our experience based on extensive routine use. NGS-based clonality testing targeting IGH FR1, FR2, FR3, and the conserved leader sequence upstream of FR1 was validated using commercially available kits. Data were analyzed by commercial and in-house-developed bioinformatics pipelines. Performance characteristics were evaluated directly comparing with capillary electrophoresis (CE) assays (BIOMED-2 primers). Assays were monitored after implementation (>1.5 years), concurrently testing by CE methods. A total of 1189 clinical samples were studied (94 validation, 1095 postimplementation). NGS showed superior performance compared with CE assays. For initial assessment, clonality detection rate was >97% for all malignancy types. Concordance with CE was 96%; discordances were related to higher sensitivity/resolution of NGS and improved detection in cases with high somatic hypermutation. Routine NGS clonality assessment is feasible and superior to existing assays, enabling accurate and specific index clone assessment and future tracking of all rearrangements in a patient sample. Successful implementation requires new standardization, validation, and implementation processes, which should be performed as a multicenter and multidisciplinary collaboration.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jmoldx.2018.10.008DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6436112PMC
March 2019

Clinical relevance of 1p and 19q deletion for patients with WHO grade 2 and 3 gliomas.

J Neurooncol 2008 Jul 15;88(3):293-8. Epub 2008 Mar 15.

Department of Neurology, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021, USA.

Purpose: To assess the frequency of chromosomes 1p and 19q deletions in gliomas and to correlate 1p deletion with prognosis in patients with grade 2 and grade 3 gliomas independently of histologic subtype.

Methods: We retrospectively evaluated 208 patients with WHO grade 2 and 3 gliomas who had 1p/19q molecular studies performed between 2000 and 2004. DNA was extracted from tumor tissue and germline material and evaluated by PCR using microsatellite markers for each chromosome.

Results: There were 113 men and 95 women with a median age at diagnosis of 40. Thirty-eight patients had a low-grade astrocytoma (A2), 58 low-grade oligodendroglioma (O2), 31 low-grade oligoastrocytoma (OA2), 21 anaplastic astrocytoma (A3), 37 anaplastic oligodendroglioma (O3), and 23 had an anaplastic oligoastrocytoma (OA3). Chromosome 1p analysis was performed in all patients and showed deletions in 105 patients (76% of O2, 42% of OA2, 21% of A2, 89% of O3, 17% of AO3, and 14% of A3). Chromosome 19q studies were performed in 118 patients and showed deletions in 46 (56% of O2, 45% of OA2, 27% of A2, 76% of O3, 11% of OA3 and 0% of A3). On multivariate analyses, chromosome 1p was a prognostic factor for prolonged PFS (HR = 1.75, P = 0.03) and OS (HR = 3.59, P = 0.02) in grade 2 gliomas but not for grade 3 (HR = 0.81, P = 0.7 for PFS; HR = 1.31, P = 0.7 for OS).

Conclusion: Chromosome 1p deletion is a significant positive prognostic marker in diffuse, grade 2 gliomas regardless of histologic subtype.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11060-008-9563-zDOI Listing
July 2008

Glioneuronal tumor with neuropil-like islands (GTNI): a report of 8 cases with chromosome 1p/19q deletion analysis.

Am J Surg Pathol 2007 Aug;31(8):1196-202

Department of Pathology, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA.

Glioneuronal tumor with neuropil-like islands (GTNI) is a rare neoplasm harboring circumscribed loci of neuronal differentiation and diffusely infiltrating astroglial and oligodendrocytelike components. We report 8 previously unpublished examples of GTNI, specifically studied for chromosome 1p and 19q allelic losses. All tumors showed characteristic histologic features and immunoprofile. One primary tumor displayed frankly malignant histology with frequent mitoses, microvascular proliferation, and necrosis. This tumor progressed within months of the initial resection. Three other tumors (2 low-grade and 1 showing only focal microvascular proliferation) recurred at 2 years, 3 years, and 1 year, respectively. All cases were evaluated for 1p/19q allelic losses by standard polymerase chain reaction-based loss of heterozygosity assays. No evidence of 1p/19q losses was found in 7 of 8 tumors. One tumor demonstrated small interstitial deletions at 1p36 (at D1S1612 and D1S513, but not at D1S548 or D1S1592) and a small interstitial deletion at 19q13 (at D19S219 and D19S412, but not at PLA2G4C). The lack of large, whole-arm 1p/19q losses (such as those found in oligodendroglial tumors), aberrant p53 expression, and the predominance of astroglial components may indicate a biologic relationship of the GTNI to diffuse astrocytoma. Although GTNI shares some morphologic features with recently reported cases of oligodendroglioma with neurocytic differentiation, the 2 tumors appear different at the molecular genetic level.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/PAS.0b013e3180335f65DOI Listing
August 2007

Allelic losses at 1p36 and 19q13 in gliomas: correlation with histologic classification, definition of a 150-kb minimal deleted region on 1p36, and evaluation of CAMTA1 as a candidate tumor suppressor gene.

Clin Cancer Res 2005 Feb;11(3):1119-28

Department of Pathology, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021, USA.

Purpose: Allelic loss at 1p is seen in 70% to 85% of oligodendrogliomas (typically in association with 19q allelic loss) and 20-30% of astrocytomas. Because most 1p deletions in gliomas involve almost the entire chromosome arm, narrowing the region of the putative tumor suppressor gene has been difficult. To better define the histologic correlates of different patterns of 1p and 19q loss, we evaluated 1p/19q status in a large group of gliomas. This also allowed us to define a very small minimal deleted region (MDR) on 1p36.

Experimental Design: Among 205 consecutive cases of glioma studied for 1p loss of heterozygosity (LOH), 112 tumors were evaluated for both 1p and 19q LOH using at least three polymorphic markers on 1p and 19q each. The latter group included both low-grade tumors (oligodendroglioma, diffuse astrocytoma, and "oligoastrocytoma") and high-grade tumors (anaplastic oligodendrogliomas, anaplastic astrocytomas, anaplastic oligoastrocytomas). Tumors with small segmental 1p losses (defined as LOH at some loci with retention of heterozygosity at other loci) were studied using a more extensive panel of markers to define the 1p MDR. The candidate gene was screened for mutations and its expression was studied by qualitative and quantitative reverse transcriptase-PCR and Northern blotting.

Results: Allelic losses on 1p and 19q, either separately or combined, were more common in classic oligodendrogliomas than in either astrocytomas or oligoastrocytomas (P < 0.0001). Classic oligodendrogliomas showed 1p loss in 35 of 42 (83%) cases, 19q loss in 28 of 39 (72%), and these were combined in 27 of 39 (69%) cases. There was no significant difference in 1p/19q LOH status between low-grade and anaplastic oligodendrogliomas. In contrast, no astrocytomas and only 6 of 30 (20%) oligoastrocytic tumors had combined 1p/19q loss. Although rare, 1p deletions were more often segmental in astrocytomas (5 of 6, 83%) than in oligodendrogliomas (3 of 35, 9%; P = 0.006). Eleven tumors (6 oligodendrogliomas or having oligodendroglial components, 5 purely astrocytic) with small segmental 1p losses underwent further detailed LOH mapping. All informative tumors in the oligodendroglial group and 2 of 3 informative astrocytomas showed LOH at 1p36.23, with a 150-kb MDR located between D1S2694 and D1S2666, entirely within the CAMTA1 transcription factor gene. Mutation analysis of the exons encoding conserved regions of CAMTA1 showed no somatic mutations in 10 gliomas, including 6 cases with and 4 cases without 1p LOH. CAMTA1 is normally expressed predominantly in non-neoplastic adult brain tissue. Relative to the latter, the expression level of CAMTA1 was low in oligodendroglial tumors and was further halved in cases with 1p deletion compared with those without 1p deletion (Mann-Whitney, P = 0.03).

Conclusions: Our data confirm the strong association of combined 1p/19q loss with classic oligodendroglioma histology and identify a very small segment of 1p36 located within CAMTA1 that was deleted in all oligodendroglial tumors with 1p LOH. This MDR also overlaps the neuroblastoma 1p36 MDR. CAMTA1 shows no evidence of inactivation by somatic mutations but its expression is reduced by half in cases with 1p LOH, suggesting that the functional effects of CAMTA1 haploinsufficiency warrant further investigation.
View Article and Find Full Text PDF

Download full-text PDF

Source
February 2005

HER-2 testing in breast cancer using immunohistochemical analysis and fluorescence in situ hybridization: a single-institution experience of 2,279 cases and comparison of dual-color and single-color scoring.

Am J Clin Pathol 2004 May;121(5):631-6

Department of Pathology, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA.

We analyzed concordance between immunohistochemical analysis and fluorescence in situ hybridization (FISH) in HER-2 status and studied the effect of dual-color (D-FISH) vs single-color FISH (S-FISH) scoring on the assignment of tumors to amplified or nonamplified categories. The assays were performed on formalin-fixed, paraffin-embedded sections of 2,279 invasive breast carcinomas. Immunohistochemical results were interpreted as negative (0, 1+) or positive (2+, 3+). For FISH analyses, a ratio for HER-2/chromosome 17 of 2.0 or more (D-FISH) or an absolute HER-2 copy number per nucleus of more than 4.0 (S-FISH) were interpreted as positive gene amplification. We found 547 (24.0%) cases positive immunohistochemically, 326 (14.3%) by D-FISH, and 351 (15.4%) by S-FISH. Overall concordance in HER-2 status with immunohistochemical analysis was 87% for D-FISH and 86% for S-FISH. Excellent concordance was found among groups scored immunohistochemically as 0, 1+, and 3+ (with D-FISH, 97%; with S-FISH, 96%). The most discordant category was the group scored 2+ immunohistochemically, in which only a quarter of the 2+ tumors were FISH(+). D-FISH and S-FISH scoring results were discordant in 89 tumors (4%), of which 8 (9%) had 3+ immunohistochemical staining and none showed high-level HER-2 amplification. Among all FISH(+) tumors, 10% were negative by immunohistochemical analysis, and notably almost half (47%) showed borderline to low HER-2 amplification (D-FISH score, 2.0-3.9); the clinical significance of these findings warrants further investigation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1309/VE78-62V2-646B-R6EXDOI Listing
May 2004

Molecular analysis of gastric washings in the diagnosis and monitoring of gastric lymphomas.

Hum Pathol 2004 May;35(5):582-6

Department of Pathology, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA.

The monitoring of gastric lymphomas is often hampered by the inherently limited sampling provided by small endoscopic biopsy specimens. To investigate the feasibility of using gastric washing fluid for monitoring patients with known gastric lymphoma and for diagnosing gastric involvement in patients with extranodal nongastric lymphoma, we collected 49 gastric washings from 39 patients (29 patients with gastric lymphoma and 10 patients with nongastric extranodal lymphoma). Collection was done at the time of follow-up biopsy and when no endoscopic abnormalities were found. DNA was extracted from the washing fluid and analyzed for clonal IgH gene rearrangement by Southern blotting (J6 probe) and/or polymerase chain reaction (PCR) (using VH-FR3 and JH primers). Forty-one of 49 samples (84%) yielded sufficient DNA for molecular analysis. Sixteen of 41 analyzable gastric washing samples (39%) failed Southern blot analysis due to degraded or insufficient DNA. Concordance between the results of Southern blot analysis of the washing and histology of the simultaneous biopsy specimen was found in 20 (80%) of the remaining 25 samples. The IgH PCR result was concordant with biopsy histology in 33 out of 41 washing samples (80%). The overall concordance between molecular clonality studies of washings (Southern blotting and/or PCR) and biopsy histology was 83% (34 of 41). Of the 7 (18%) discrepant specimens, 2 were diagnosed histologically as lymphoma, but the simultaneous washings were negative by molecular studies. Five biopsy specimens were histologically benign, but the corresponding washings demonstrated clonal IgH gene rearrangement (3 cases by PCR and 2 cases by Southern blotting). This study demonstrates the diagnostic utility of molecular clonality analysis of gastric washings.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.humpath.2003.12.008DOI Listing
May 2004

Impact of polysomy 17 on HER-2/neu immunohistochemistry in breast carcinomas without HER-2/neu gene amplification.

J Mol Diagn 2003 Aug;5(3):155-9

Department of Pathology, Memorial Sloan-Kettering Cancer Center, New York, New York 10021, USA.

Her-2/neu, a proto-oncogene located on chromosome 17, is an important biomarker in breast carcinoma. Immunohistochemistry (IHC) is currently the most widely used method for assessing Her-2/neu status. Some IHC-positive cases do not show Her-2/neu gene amplification by fluorescence in situ hybridization (FISH). It has been suggested that some of these IHC "false positive" results may in part be due to increased copy number of chromosome 17 resulting in increased Her-2/neu protein expression. We analyzed IHC and FISH data from 561 cases of invasive breast carcinoma to test this hypothesis. IHC and FISH for Her-2/neu were performed on formalin-fixed, paraffin-embedded sections of 561 invasive breast carcinomas. The IHC results were interpreted as 0, 1+, 2+, or 3+ according to the manufacturer's recommended criteria. The FISH results were expressed as a ratio of Her-2/neu/chromosome 17 and were interpreted as positive (> = 2.0) or negative (<2.0) for gene amplification according to the manufacturer's recommended scoring system. We found that in IHC 3+/FISH-negative cases (n = 15) both the average chromosome 17 copy number and the average Her-2/neu copy number were significantly higher than that in IHC (0 to 2+)/FISH-negative cases (n = 411) (2.45 vs. 1.68; P < 0.0001, and 3.19 vs. 1.95; P < 0.0001, respectively). In contrast, the IHC 2+/FISH-negative cases did not exhibit a significantly increased number of chromosome 17 compared to IHC 0 to 1+ cases. In addition, the average copy number of chromosome 17 in FISH-positive cases (n = 135) was significantly higher than that in FISH-negative cases (n = 426) (2.27 vs. 1.70; P < 0.0001), indicating a general association of increased chromosome 17 copy number with Her-2/neu gene amplification. Thus, our data suggest that IHC 3+ immunostaining without scorable gene amplification may indeed be, at least in some cases, the result of increased Her-2/neu protein expression secondary to an increased copy number of chromosome 17, associated with an increased total number of Her-2/neu gene copies per tumor cell.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1907330PMC
http://dx.doi.org/10.1016/S1525-1578(10)60467-9DOI Listing
August 2003