BACKGROUND:Ewing sarcoma/peripheral neuroectodermal tumor (EWS/PNET), since its characterization immunophenotypically and cytogenetically, has emerged as one of most common sarcomas of childhood. Currently, it is recognized that EWS/PNET can occur in any number of extraosseous sites and is one of several distinctive tumor types with an EWS translocation. In the past, the pathologic diagnosis of EWS/PNET relied on an open biopsy with the application of various ancillary studies, ranging from periodic acid-Schiff stain to molecular testing, but the tumor increasingly is diagnosed on the basis of cytologic specimens alone.METHODS:The authors report 3 cases of EWS/PNET in patients aged 11 years to 53 years. These 3 patients had tumors that involved the parotid gland, cervical soft tissue, and pelvis, and were diagnosed by cytologic evaluation of fine-needle aspiration (FNA) biopsy material alone. The FNA materials also were evaluated prospectively by fluorescence in situ hybridization and/or reverse transcriptase-polymerase chain reaction.RESULTS:The results emphasized the diagnostic utility of FNA biopsy material for morphologic and molecular analysis without compromising conventional cytologic and immunocytochemical analysis, and that prospective molecular testing of FNA specimens has utility in routine practice although it is subject to many of the same limitations that impact molecular analysis when applied to conventional tissue biopsy specimens.CONCLUSIONS:The current results demonstrated that molecular genetic techniques can provide clinically useful ancillary information for FNA specimens when cytologic features and/or immunophenotype are equivocal on the basis of limited sampling or secondary changes, such as hemorrhage and/or necrosis.
Individual classes of human endogenous retrovirus (HERV) genes and proteins are expressed in cancer, but expression of more than one type of HERV is rare. We report here the expression of multiple HERV genes and proteins in ovarian cell lines and tissues. Expression of HERV‐K env mRNA was greater in ovarian epithelial tumors than in normal ovarian tissues ( N = 254). The expression of this protein on the surface and in the cytoplasm of ovarian cancer cells was confirmed using anti‐HERV‐K specific antibody by flow cytometric analysis. The frequency of expression of HERV‐K env protein in multitissue microarrays ( N = 641) was determined by immunohistochemistry and a significant correlation with tumor histotype was found. A significantly increased expression of HERV‐K was observed in tumors with low malignant potential and low grade, relative to expression in normal ovarian tissues. The increase in expression of HERV‐K env protein took place in a stepwise fashion in serous papillary adenocarcinoma. Interestingly, we found that other classes of HERV env mRNAs, including ERV3 and HERV‐E, are expressed in the same ovarian cancer tissues that expressed HERV‐K. Furthermore, anti‐HERV antibodies including anti‐ERV3 (30%), anti‐HERV‐E (40%) and anti‐HERV‐K (55%) were detected in patients with ovarian cancer, but not in normal female controls. HERV env proteins are frequently transcribed and translated in ovarian epithelial tumors, and multiple HERV families are detectable in ovarian cancer. HERV env proteins, and especially those expressed on the cell surface, may serve as novel tumor targets for detection, diagnosis and immunotherapy of ovarian cancer. © 2006 Wiley‐Liss, Inc.
Carcinomas of the nose and paranasal sinuses are a heterogeneous group of neoplasms that differ histologically, biologically, and clinically. Some of these tumors are known to harbor high-risk human papillomavirus (HPV) DNA. In an attempt to identify specific phenotypes associated with HPV infection, 39 cases of sinonasal carcinomas were evaluated by PCR for the presence of HPV DNA. The tumors were also studied with a panel of immunohistochemical stains, including p16, p53, and Ki-67 antibodies. Twenty-one cases were identified as keratinizing squamous cell carcinoma (KSCC) with a male-to-female ratio of 3:1. Eight cases were nonkeratinizing (cylindrical cell) carcinoma (NKCa) with a male-to-female ratio of 1:1. Ten cases were sinonasal undifferentiated carcinoma (SNUC), and 9 of these patients were men. HPV DNA, particularly type 16, was detected in 9 cases: 4 of 21 (19%) of KSCC, 4 of 8 (50%) of NKCa, and 1 of 10 (10%) of SNUC. In addition to a higher prevalence of HPV DNA in NKCa, the tumors also showed a distinct immunophenotype characterized by strong and diffuse staining for p16, high labeling scores for Ki-67, and negative or low reactivity to p53. On the other hand, KSCC and SNUC were either negative or weakly reactive to p16 antibodies. KSCC cases were more likely to be positive and more strongly reactive to p53 stain. Unlike KSCC, SNUC had high Ki-67 labeling scores. These observations suggest that NKCa of the sinonasal tract is a distinct histopathologic and molecular disease entity, which should be added to the list of upper aerodigestive tract tumors with strong etiologic relationship to high risk HPV.
BACKGROUND: High grade squamous intraepithelial lesion (HSIL) of the cervix is well known to be associated with human papillomavirus (HPV) infection. HSIL and invasive carcinomas occurring synchronously in genital malformations, such as a double cervix, have been reported. It has been postulated that the field effect phenomenon of HPV infection is responsible for this synchronous infection. However, there is no information in the literature on the specific types of HPV causing the concomitant lesions in cases with a double cervix.CASE: A 33-year-old nulligravida with a double cervix and a single uterine corpus was diagnosed with bilateral HSIL on Papanicolaou-stained ThinPrep slides (Cytyc Corp., Boxborough, Massachusetts, U.S.A.). A bilateral loop electrosurgical excision procedure cone biopsy revealed HSIL involving both cervices. DNA extracted from the HSIL lesions was analyzed by a polymerase chain reaction-based assay for the presence of HPV. High-risk HPV type 33 was identified in the right cervix, while HPV type 35 was present in the left.CONCLUSION: Demonstration of high-risk HPV types bilaterally supported the etiologic role of HPV infection in the synchronous and bilateral occurrence of HSIL in this case of a double cervix. The HPV types were different in the right and left cervices.
Primary small cell carcinomas of the uterine cervix are uncommon but highly aggressive malignancies. The recent observations that c-kit proto-oncogene, a tyrosine kinase, is overexpressed in small cell lung cancers and that advanced c-kit-expressing gastrointestinal stromal tumors were successfully treated with a selective tyrosine kinase inhibitor STI-571 (Gleevec, imatinib mesylate) prompted us to investigate c-kit protein expression in cervical small cell carcinomas. Using a polyclonal antibody against c-kit protein (CD117), our immunohistochemical studies demonstrated a cytoplasmic staining in six of 22 cases (27%) of cervical small cell carcinoma. However, in five of these c-kit-positive cases, the immunoreactivity was focal and/or weak. Only one case (5%) exhibited a strong and diffuse staining pattern comparable to that seen in gastrointestinal stromal tumors. This was in contrast to small cell lung cancers where a positive staining for c-kit was observed in nine of 14 cases (64%) included in the study for comparison. Among them, five (36%) exhibited a strong and diffuse staining pattern. These results indicate that overexpression of c-kit protein is an infrequent event in small cell carcinomas of the uterine cervix. In comparison with small cell lung cancers, the findings presented in this report may reflect the difference in etiopathogenetic mechanisms underlying these two types of small cell carcinomas.
OBJECTIVE: To demonstrate that cellular preparations requiring color analysis of different domains stained by molecular cytogenetic methods (fluorescence in situ hybridization) can be processed by spectral analysis of fluorescent emissions by either factor analysis of medical image sequences (FAMIS) or a META confocal configuration to isolate fluorescent probes. STUDY DESIGN: Three-dimensional sequences of images obtained by spectral analysis in a META confocal microscope (Carl Zeiss SAS, Jena, Germany) were analyzed by META processing and the FAMIS algorithm, which provides factor curves. META and factor images were then the result of image-processing methods that cover emission spectra. RESULTS: Factor curves and factor or META images can help to analyze targets inside nuclei. CONCLUSION: It is possible to process preparations containing numerous spots on different colors to differentiate stained targets and to improve visualization and detection.
BACKGROUND: The columnar and tall cell variants of papillary thyroid carcinoma (PTC) are uncommon variants and have Generally been regarded as more aggressive forms in comparison to the more common classic papillary and follicular subtypes. Cytologic diagnosis of these rare variants is elusive since the characteristic nuclear features of the usual papillary thyroid carcinoma are very often absent or inconspicuous. We present a case Of the columnar cell variant of PTC in a young woman that demonstrates the diagnostic challenge. CASE: A 24-year-old woman presented with a solitary, 3-cm mass in the left aspect of the thyroid. The aspirate consisted of a moderately cellular sampling of sheets, papillary clusters and microfollicles of cells with oval nuclei and uniform, finely granular chromatin. These cells were arranged in a peudostratified manner around well-defined fibrovascular cores. There were no intranuclear inclusions or well-defined nuclear grooves in the cells of the aspirate. There was also absence of colloid despite the presence of well-formed follicles. The resected thyroid revealed a columnar cell variant of PTC. CONCLUSION: The cytologic features of columnar cell-type PTC are at variance with those of classic PTC and are elusive in fine needle aspiration cytology. It is the lack of classic cytologic features of PTC that is distinctly apparent, yet it is the monomorphism of cells in the aspirate, their papillary configuration and their pseudostratification in well-formed fibrovascular cores that are the keys to the diagnosis. Immunohistochemical staining to rule out other thyroid neoplasms can be performed to aid in the diagnosis.
The cytological evaluation of ovarian cystic fluid using ThinPrep has not been reported. To determine the diagnostic accuracy of ThinPrep cytology in distinguishing between benign and nonbenign ovarian cystic lesions, we examined 65 fluid samples aspirated during intraoperative consultation with subsequent histologic correlation. One ThinPrep slide was prepared from each sample aspirated from surgically removed ovarian cystic masses and reviewed blindly by a panel of three cytopathologists. The parameters used in cytological evaluation were cellularity, cell types, cellular arrangement, and background. Four samples were acellular and excluded from the study. The consensus cytologic diagnoses were compiled for 61 cases which were assigned to one of the following diagnostic categories: negative for malignant cells (40 cases), atypical cytology (13 cases), and suspicious or positive for malignancy (8 cases). Histologic correlation of the cytological benign/negative cases showed that 26/40 (65%) were histologically benign and 14/40 were false‐negative (35%, 5 carcinomas and 9 borderline tumors) with 10 of these cases being mucinous tumors. Most false‐negative cytologic samples (11/14 or 79%) did not have an epithelial component. Of the 21 cytological nonbenign diagnoses (atypical/suspicious/positive), 15 (71%) were confirmed on histology (10 carcinomas and 5 borderline tumors). However, a nonbenign cytologic diagnosis was rendered in 6 histologically benign cases, including 2 serous cystadenomas, 1 mucinous cystadenoma, 1 serous cystadenofibroma, 1 endometriosis, and 1 corpus luteal cyst. The diagnostic sensitivity by ThinPrep evaluation of ovarian cystic masses is 81% (26/32) for benign and 52% (15/29) for nonbenign lesions. Our results concluded that ThinPrep examination of ovarian cystic fluid is not accurate in distinguishing benign from malignant cysts, given the significant number of false‐negative diagnoses. Major contributing factors include sparse cellularity of the fluid samples and mucinous differentiation of the tumors. Diagn. Cytopathol. 2004;30:320–324. © 2004 Wiley‐Liss, Inc.
OBJECTIVE: To estimate the outcome of adolescents with atypical squamous cells of undetermined significance (ASC-US) on cytology.METHODS: A review of ASC-US cytology in girls and women aged 10-19 years between 1995 and 1999 was performed. The cytologic and histologic follow-up of each patient was evaluated. The outcome was recorded as the most significant (highest grade) subsequent cervical smear or biopsy.RESULTS: Overall, 535 of 7,897 (6.8%) cervical cytologic specimens were reported as ASC-US. The study group consisted of 398 patients for whom pathologic follow-up was available. The mean duration of follow-up was 19 months. Follow-up consisted of repeat cytology in 251 (63%) patients and colposcopy with cervical biopsies and/or endocervical curettage in 147 (37%) of the adolescents. Two hundred fifty-three (64%) adolescents had no pathologic abnormalities on follow-up. Persistent ASC-US was identified in 65 (16%), low-grade squamous intraepithelial lesions/cervical intraepithelial neoplasia (CIN) 1 was found in 44 (11%) and high-grade squamous intraepithelial lesions/CIN 2 or 3 occurred in 36 (9%) of the adolescents. No cases of invasive carcinoma were found.CONCLUSIONS: Among adolescents with ASC-US, the rate of squamous intraepithelial lesions/CIN is similar to that of adults. Although the optimal management of ASC-US in adolescents is unknown, these patients warrant dose follow-up. (C) 2004 by The American College of Obstetricians and Gynecologists.
BACKGROUND:The columnar and tall cell variants of papillary thyroid carcinoma (PTC) are uncommon variants and have generally been regarded as more aggressive forms in comparison to the more common classic papillary and follicular subtypes. Cytologic diagnosis of these rare variants is elusive since the characteristic nuclear features of the usual papillary thyroid carcinoma are very often absent or inconspicuous. We present a case of the columnar cell variant of PTC in a young woman that demonstrates the diagnostic challenge.CASE:A 24-year-old woman presented with a solitary, 3-cm mass in the left aspect of the thyroid. The aspirate consisted of a moderately cellular sampling of sheets, papillary clusters and microfollicles of cells with oval nuclei and uniform, finely granular chromatin. These cells were arranged in a peudostratified manner around well-defined fibrovascular cores. There were no intranuclear inclusions or well-defined nuclear grooves in the cells of the aspirate. There was also absence of colloid despite the presence of well-formed follicles. The resected thyroid revealed a columnar cell variant of PTC.CONCLUSION:The cytologic features of columnar cell-type PTC are at variance with those of classic PTC and are elusive in fine needle aspiration cytology. It is the lack of classic cytologic features of PTC that is distinctly apparent, yet it is the monomorphism of cells in the aspirate, their papillary configuration and their pseudostratification in well-formed fibrovascular cores that are the keys to the diagnosis. Immunohistochemical staining to rule out other thyroid neoplasms can be performed to aid in the diagnosis.
Human papillomaviruses (HPVs) are important in the development of human cancers, including cervical and oral tumors. However, most existing methods for HPV typing cannot routinely distinguish among the more than 100 distinct types of HPV or the natural HPV intratypic variants that have also been documented. To address this problem, we developed a novel method, general primer-denaturing high-performance liquid chromatography (GP-dHPLC), for the detection and typing of genital HPV using an automated 96-well plate format. GP-dHPLC uses general primer PCR (GP-PCR) to amplify the viral DNA and then analyzes the GP-PCR products by denaturing high-performance liquid chromatography (dHPLC). A number of different primer pairs with homology to most known genital HPV types were tested, and the L1C1-L1C2M pair specific for the L1 region of the viral genome was chosen. A set of HPV standard control patterns, consisting of those for HPV types 16, 18, 31, 33, 39, 45, 51, 52, 56, 58, 59, 6, and 11, was established for genital HPV typing. One hundred eighty-six frozen and formalin-fixed cervical cancer tissue samples were analyzed for the presence of HPV and the HPV type by this method, and 95.8% of them were found to contain HPV DNA. GP-dHPLC accurately discriminated among HPV variants that differed by as little as one nucleotide. Several new variants of HPV types 16, 18, 39, 45, 52, and 59 were identified. Moreover, multiple HPV infections were detected in 26.6% of the samples. Our results indicate that HPV typing by GP-dHPLC permits discrimination of common genital HPV types, detection of multiple HPV infections, and identification of HPV variants in clinical samples.
Squamous cell carcinoma of the head and neck commonly affects patients in their sixth decade and older, particularly those with a prolonged history of alcohol and tobacco abuse. Less frequently, carcinomas occur in young individuals even in the absence of known risk factors. The purpose of this study is to investigate a possible relationship between these tumors and human papilloma virus (HPV). Thirty-three cases of squamous cell carcinoma of the head and neck in young patients under the age of 40 years were studied: 15 oral, 11 tonsillar, and 7 laryngeal. HPV DNA was detected by polymerase chain reaction in 10 tonsillar and 2 laryngeal carcinomas and in none of the oral tumors. Of the 12 HPV-positive tumors, 11 were HPV16 and 1 was HPV31. HPV-positive tumors had a distinct nonkeratinizing basal cell morphology, they stained diffusely and strongly with p16 antibodies, had higher Ki-67 and lower p53 staining scores as compared with the conventional keratinizing HPV negative carcinomas. It is concluded that in young patients high-risk HPV, particularly HPV16, is strongly associated with tonsillar squamous cell carcinoma and some cases of laryngeal, but not oral, tumors. The HPV-positive carcinomas have a distinct histopathologic and immunophenotypic features.
The expression of human endogenous retrovirus (HERV) mRNA and proteins was associated recently with diseases that include human malignancies. The authors report that, in the current study, transcripts encoding the envelope region of an HERV family, HERV‐E, were expressed in human prostate carcinoma.
Human papillomavirus (HPV) has been implicated as an etiologic agent for the development of squamous cell carcinoma of the anorectal region. It has been shown that the HPV E6 and E7 oncoproteins are able to inactivate the tumor suppressor functions of p53 and Rb. In cervical and head and neck cancers, HPV infection is also associated with an overexpression of p16, a cyclin-dependent kinase inhibitor. The expression of these cell cycle regulators in squamous cell carcinomas of the anorectal region has not been well studied. In the current study, 29 cases of squamous cell carcinoma of the anorectal region were immunohistochemically examined for the expression of p16, Rb, and p53 proteins. Tumor cell DNA was also extracted from paraffin blocks and subjected to broad-spectrum HPV DNA testing and typing. The results show that the tumor cells exhibited a strong and diffuse nuclear stain (with some cytoplasmic positivity) for p16 in all 29 cases (100%). The adjacent nonneoplastic squamous epithelium or colonic mucosa, in contrast, was completely negative. Loss of Rb nuclear staining in tumor cells was observed in 20 cases (69%). The p53 protein was essentially undetectable, with only 6 cases containing <10% positive cells. HPV DNA was detected in every case (100%), with 25 cases (86%) harboring Type 16. In addition, almost identical results were obtained in 12 HPV-positive squamous cell carcinomas of the upper aerodigestive tract. This was in marked contrast to those of HPV-negative tumors, where positive p16 staining and loss of Rb expression were seen in only 2/21 (10%) and 1/21 (5%) cases, respectively. These observations indicate that overexpression of p16 and loss of Rb nuclear staining are commonly associated with high-risk HPV infection, which may serve as useful surrogate biomarkers for identifying squamous cell carcinomas harboring HPV DNA.
OBJECTIVE:To determine the prevalence and typing of HPV DNA in pregnant women with a diagnosis of atypical squamous cells (ASC) and to assess whether pregnancy-related changes contribute to the diagnosis of ASC.STUDY DESIGN:HPV testing was performed on residual specimens from the ThinPrep Pap test (Cytyc Corp., Boxborough, Massachusetts, U.S.A.) in pregnant women diagnosed as ASC (study group, n = 105), low and high grade squamous intraepithelial lesion (LSIL and HSIL) (positive control, n = 33) and negative for epithelial cell abnormality (negative control, n = 20). All cases were reviewed by 2 cytopathologists to obtain consensus diagnoses using the Bethesda System 2001 criteria. The study group cases were further subcategorized into ASC of undetermined significance (ASCUS, n = 99) and ASC cannot exclude HSIL (ASC-H, n = 6). HPV testing was also performed on an ASC control group consisting of 68 consecutive ASC cases in nonpregnant women, matched by age.RESULTS:Mean patient age was 23.7 years for the study group and 25.6 years for the ASC control group. HPV DNA was detected in 88.6% of cases in the study group, including 87.9% of ASC-US and 100% of ASC-H cases. Of the HPV positive cases, 79.6%, 4.3%, 5.4% and 10.8% had high-risk, mixed high- and low-risk, low-risk and unknown HPV types, respectively. The most frequent HPV types detected were: types 52 (31.2%), 16 (15.1%), 39 (11.8%), 53 (10.8%), and 18 and 58 (9.7% each). Multiple viral types were detected in 43.0% of cases. The prevalence of HPV DNA in the positive and negative controls in pregnant women was 100% and 55%, respectively. HPV DNA was detected in 83.8% of the ASC control group.CONCLUSION:Regardless of pregnancy-related changes, the prevalence of HPV DNA in pregnant women (88.6%) was similar to that found in ASC in nonpregnant women of the same reproductive-age group (83.8%), and the high-risk types accounted for the vast majority of cases (83.9%). These findings demonstrate that pregnancy-related changes do not contribute to the diagnosis of ASC in this subset of women. Furthermore, the high HPV DNA prevalence in reproductive-age women (< 40 years) suggests that HPV testing may have limited utility in effective management of these patients.
Human endogenous retroviruses (HERVs) comprise up to 8% of the human genome. In previous studies, we demonstrated that type 1 HERV-K envelope (env) transcripts are expressed in most human breast cancers, but not in normal breast tissues. In the current study, we report that type 2 HERV-K env transcripts are also present in human breast cancers. By real-time RT–PCR, the expression of HERV-K env transcripts was 5–10-fold higher in breast cancer cell lines treated with estradiol and progesterone than in cells without treatment, and expression was significantly higher in most breast cancer tissues than in normal breast tissues. Furthermore, both types of HERV-K env transcripts were capable of being spliced into subgenomic env transcripts and various splice donor and acceptor sites were detected in breast cancers. The selective expression and distribution of multiple HERV-K endogenous retroviral element splice variants in breast cancer, but not in normal controls, suggests that they are novel breast tumor markers.
Histologic criteria of low-grade vulvar/vaginal intraepithelial neoplasia (VIN1/VAIN1) are well established; however, a significant interobserver variability in diagnosing VIN1/VAIN1 has been reported. The goal of this study was to evaluate the utility of MIB-1 immunostaining as an adjunct test to increase the diagnostic accuracy in equivocal cases of VIN1/VAIN1. The second goal was to examine the distribution of low- and high–oncogenic risk human papillomaviruses (HPVs) in VIN1/VAIN1 lesions. Consecutive vulvar/vaginal biopsies originally diagnosed as VIN1/VAIN1 ( n = 43) or benign ( n = 20) were reviewed by two pathologists to obtain a consensus diagnosis. The diagnosis was further confirmed with HPV testing using Short PCR Fragment 10 and Line Probe Assay. MIB-1 immunostaining was performed, and positive staining was defined as a cluster of two or more stained nuclei in the upper two thirds of the epithelial thickness. After verification of the diagnosis using the consensus histologic review and HPV detection as an objective confirmatory test, 31% of cases originally diagnosed as VIN1/VAIN1 were identified as being overdiagnosed. The sensitivity and the specificity of MIB-1 staining for identifying VIN1/VAIN1 were 0.96 and 0.90, respectively. Seventy percent of VIN1 cases were associated with low-risk viral types. In contrast, the majority (84%) of VAIN1 cases were associated with high-risk HPVs. In conclusion, MIB-1 staining is sensitive and specific for identifying VIN1/VAIN1, helpful in verifying the diagnosis in equivocal cases.
Fadi W. Abdul-Karim Pedro P. de Agustín Måns Åkerman M. Loredana Gadda Alasio Patricia Alonso de Ruiz Carmen Alvarez-Santin Ana-Cristina Anton Karen M. Atkison Silvana Audy-Jurkovic R. Marshall Austin Jan P. A. Baak Ulrik Baandrup Gunter F. Bahr Peter H. Bartels Sandra H. Bigner John W. Bishop Miklós Bodó Thomas A. Bonfiglio Mathilde E. Boon Gerhard Breitenecker Lukas Bubendorf Ursula Buerzele-Fricke Jorge Campos R. de C. Carol A. Carriere Tien-Chun Chang Patricia Chapman Annie N. Y. Cheung William N. Christopherson Douglas P. Clark Edith Claros Mercado Luiz Martins Collaco Brian T. Collins William N. Crabtree Peter Dalquen Dilip K. Das Diane D. Davey Denise DeFrias Margaret Douglas Manfred Droese Antonio Ducrot-Schinini Hormoz Ehya Yener S. Erozan Clarice Amaral Ferreira Norman W. Fitzgerald Brendan T. Fitzpatrick Alessandra M. Forni Hugo Galera-Davidson Kim R. Geisinger Claude Gompel Ricardo González-Cámpora Zenon Gonzalez-Romero Roberta M. Goodell Philippe de Graeve Shirley E. Greening Heinz K. Grohs Prabodh K. Gupta Steven I. Hajdu Xhevdet Harasani Ernst Held Michael R. Henry Manuel Hilgarth Anders Hjerpe J. Heinrich Holzner O. A. N. Husain Martha L. Hutchinson Hideo Ikeda Lucrecia Illescas Stanley L. Inhorn Matías Jiménez-Ayala William W. Johnston David B. Kaminsky Kusum Kapila Harubumi Kato Ruth L. Katz Tadao K. Kobayashi Jitka Kobilková Leopold G. Koss Helen A. Koutselini Rainer Kraft Paul A. Krieger Perikala V. Kumar Sow-Hsong Kuo Reviewers and Consultants