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"Crum, Christopher P."
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Peritoneal Dissemination Complicating Morcellation of Uterine Mesenchymal Neoplasms
by
Seidman, Michael A.
,
Nucci, Marisa R.
,
Quade, Bradley J.
in
Adult
,
Biological products
,
Biology
2012
Power morcellation has become a common technique for the minimally invasive resection of uterine leiomyomas. This technique is associated with dissemination of cellular material throughout the peritoneum. When morcellated uterine tumors are unexpectedly found to be leiomyosarcomas or tumors with atypical features (atypical leiomyoma, smooth muscle tumor of uncertain malignant potential), there may be significant clinical consequences. This study was undertaken to determine the frequency and clinical consequence of intraperitoneal dissemination of these neoplasms.
From 2005-2010, 1091 instances of uterine morcellation were identified at BWH. Unexpected diagnoses of leiomyoma variants or atypical and malignant smooth muscle tumors occurred in 1.2% of cases using power morcellation for uterine masses clinically presumed to be \"fibroids\" over this period, including one endometrial stromal sarcoma (ESS), one cellular leiomyoma (CL), six atypical leiomyomas (AL), three smooth muscle tumor of uncertain malignant potential (STUMPs), and one leiomyosarcoma (LMS). The rate of unexpected sarcoma after the laparoscopic morcellation procedure was 0.09%, 9-fold higher than the rate currently quoted to patients during pre-procedure briefing, and this rate may increase over time as diagnostically challenging or under-sampled tumors manifest their biological potential. Furthermore, when examining follow-up laparoscopies, both from in-house and consultation cases, disseminated disease occurred in 64.3% of all tumors (zero of one ESS, one of one CL, zero of one AL, four of four STUMPs, and four of seven LMS). Only disseminated leiomyosarcoma, however, was associated with mortality. Procedures are proposed for pathologic evaluation of morcellation specimens and associated follow-up specimens.
While additional study is warranted, these data suggest uterine morcellation carries a risk of disseminating unexpected malignancy with apparent associated increase in mortality much higher than appreciated currently.
Journal Article
Serous tubal intraepithelial neoplasia: the concept and its application
by
Brouwer, Jan
,
Crum, Christopher P
,
Meserve, Emily E K
in
631/67/1517/1709
,
692/420/755
,
Carcinoma in Situ - pathology
2017
In recent years it has become clear that many extra-uterine (pelvic) high-grade serous carcinomas (serous carcinomas) are preceded by a precursor lesion in the distal fallopian tube. Precursors range from small self-limited ‘p53 signatures' to expansile serous tubal intraepithelial neoplasms that include both serous tubal epithelial proliferations (or lesions) of uncertain significance and serous tubal intraepithelial carcinomas. These precursors can be considered from three perspectives. The first is biologic underpinnings, which are multifactorial, and include the intersection of DNA damage with Tp53 mutations and disturbances in transcriptional regulation that increase with age. The second perspective is the morphologic discovery and classification of intraepithelial neoplasms that are intercepted early in their natural history, either incidentally or in risk-reduction surgeries for germline mutations. For the practicing pathologist, as well as the investigators, a distinction between a primary intraepithelial neoplasm and an intramucosal carcinoma must be made to avoid misinterpreting (or underestimating) the significance of these proliferations. The third perspective is the application of this information to intervention, devising strategies that will actually lower the ovarian cancer death rate by opportunistic salpingectomy, widespread comprehensive genetic screening and early detection. Central to this issue are the questions of (1) whether some STICs are metastatic, (2) whether lower-grade epithelial proliferations can invade prior to evolving into intraepithelial carcinoma, or (3) metastasize and become malignant elsewhere (‘precursor escape'). An important caveat is the persistent and unsettling reality that many high-grade serous carcinomas are not associated with an obvious point of initiation in the fallopian tube. The pathologist sits squarely in the midst of all of these issues, and has a pivotal role in managing expectations for stemming the death rate from this lethal disease.
Journal Article
Molecular characterization of diffuse malignant peritoneal mesothelioma
2020
Malignant peritoneal mesothelioma is a rare aggressive tumor that arises from the peritoneal lining. While recurrent BAP1 mutations have been identified in a subset of mesotheliomas, molecular characteristics of peritoneal mesotheliomas, including those lacking BAP1 alterations, remain poorly understood. Using targeted next-generation sequencing, we examined the molecular features of 26 diffuse malignant peritoneal mesotheliomas. As part of an exploratory analysis, we analyzed an additional localized peritoneal mesothelioma and one well-differentiated papillary mesothelioma with invasive foci. Genomic characterization identified categories of diffuse malignant peritoneal mesotheliomas: The first group included 18 (69%) tumors with recurrent BAP1 alterations, with eight (31%) having more than one BAP1 alterations, and concomitant alterations in PBRM1 (46%) and SETD2 (35%). All tumors with complete loss of BAP1 expression by immunohistochemistry harbored BAP1 molecular alterations. PBRM1 alterations were significantly enriched in the BAP1-altered cohort. Frequent copy number loss of BAP1, ARID1B, PRDM1, PBRM1, SETD2, NF2, and CDKN2A was noted. The second group included eight (31%) BAP1-wild-type tumors: two with TP53 mutations, one with a TRAF7 activating mutation, one with a SUZ12 inactivating mutation, and three with ALK rearrangements that we previously published. One TP53-mutant biphasic mesothelioma showed evidence of genomic near-haploidization showing loss of heterozygosity of all chromosomes except 5, 7, 16, and 20. The localized peritoneal mesothelioma harbored a nonsense CHEK2 mutation, and the well-differentiated papillary mesothelioma with invasive foci harbored no reportable variants. In conclusion, we described the genetic categories of diffuse malignant peritoneal mesotheliomas, with BAP1-mutant and BAP1-wild-type groups. Our findings implicated DNA repair, epigenetics, and cell cycle regulation in the pathogenesis of peritoneal mesotheliomas, with identification of potential therapeutic targets.
Journal Article
Human papillomavirus E7 oncoprotein induces KDM6A and KDM6B histone demethylase expression and causes epigenetic reprogramming
by
McLaughlin-Drubin, Margaret E
,
Crum, Christopher P
,
Münger, Karl
in
Biological Sciences
,
Biomarkers
,
Cancer
2011
Despite the availability of vaccines, human papillomavirus (HPV) infections remain a cause of significant cancer morbidity and mortality. We have previously shown that HPV16 E7 associates with and diminishes E2F6-containing polycomb repressive complexes. Here, we show that repressive trimethyl marks on lysine 27 of histone 3, which are necessary for binding of polycomb repressive complexes, are decreased in HPV16 E7-expressing cells and HPV16-positive cervical lesions. This is caused by transcriptional induction of the KDM6A and KDM6B histone 3 lysine 27-specific demethylases. HPV16 E7-mediated KDM6B induction accounts for expression of the cervical cancer biomarker, p16INK⁴A. Moreover, KDM6A- and KDM6B-responsive Homeobox genes are expressed at significantly higher levels, suggesting that HPV16 E7 results in reprogramming of host epithelial cells. These effects are independent of the ability of E7 to inhibit the retinoblastoma tumor suppressor protein. Most importantly, these effects are reversed when E7 expression is silenced, indicating that this pathway may have prognostic and/or therapeutic significance.
Journal Article
discrete population of squamocolumnar junction cells implicated in the pathogenesis of cervical cancer
by
Xian, Wa
,
Laury, Anna
,
Herfs, Michael
in
Adult
,
Alphapapillomavirus - immunology
,
Alphapapillomavirus - isolation & purification
2012
Infection by carcinogenic human papillomaviruses (HPV) results in precancers [cervical intraepithelial neoplasia (CIN)] and cancers near the ectoendocervical squamocolumnar (SC) junction of the cervix. However, the specific cells targeted by HPV have not been identified and the cellular origin of cervical cancer remains elusive. In this study, we uncovered a discrete population of SC junctional cells with unique morphology and gene-expression profile. We also demonstrated that the selected junctional biomarkers were expressed by a high percentage of high-grade CIN and cervical cancers associated with carcinogenic HPVs but rarely in ectocervical/transformation zone CINs or those associated with noncarcinogenic HPVs. That the original SC junction immunophenotype was not regenerated at new SC junctions following excision, not induced by expression of viral oncoproteins in foreskin keratinocytes, and not seen in HPV-related precursors of the vagina, vulva, and penis further support the notion that junctional cells are the source of cervical cancer. Taken together, our findings suggest that carcinogenic HPV-related CINs and cervical cancers are linked to a small, discrete cell population that localizes to the SC junction of the cervix, expresses a unique gene expression signature, and is not regenerated after excision. The findings in this study uncover a potential target for cervical cancer prevention, provide insight into the risk assessment of cervical lesions, and establish a model for elucidating the pathway to cervical cancer following carcinogenic HPV infection.
Journal Article
Intercepting pelvic cancer in the distal fallopian tube: Theories and realities
2009
The pathogenesis of high-grade serous carcinoma of the ovary has come into sharper focus as closer attention has been paid to the earlier phases of this disease. The study of patients with BRCA mutation has been of particular value, in as much as the examination of prophylactic salpingo-oophorectomies will reveal an early cancer in approximately 5% of individuals. Recently studies have shown that about 80% of these early carcinomas originate in the distal fallopian tube. This review summarizes the recent data supporting the distal fallopian tube as an important site for serous carcinogenesis, stressing both the presence of a novel precursor (the p53 signature) and the application of this model to all women irrespective of BRCA status. The challenges and unmet needs unmasked by this paradigm shift in ovarian cancer research are discussed.
Journal Article
Diagnostic potential for a serum miRNA neural network for detection of ovarian cancer
by
Elias, Kevin M
,
Frendl, Gyorgy
,
Konstantinopoulos, Panagiotis
in
Aged
,
Biomarkers, Tumor - blood
,
Cancer Biology
2017
Recent studies posit a role for non-coding RNAs in epithelial ovarian cancer (EOC). Combining small RNA sequencing from 179 human serum samples with a neural network analysis produced a miRNA algorithm for diagnosis of EOC (AUC 0.90; 95% CI: 0.81–0.99). The model significantly outperformed CA125 and functioned well regardless of patient age, histology, or stage. Among 454 patients with various diagnoses, the miRNA neural network had 100% specificity for ovarian cancer. After using 325 samples to adapt the neural network to qPCR measurements, the model was validated using 51 independent clinical samples, with a positive predictive value of 91.3% (95% CI: 73.3–97.6%) and negative predictive value of 78.6% (95% CI: 64.2–88.2%). Finally, biologic relevance was tested using in situ hybridization on 30 pre-metastatic lesions, showing intratumoral concentration of relevant miRNAs. These data suggest circulating miRNAs have potential to develop a non-invasive diagnostic test for ovarian cancer.
Ovarian cancer is a major cause of cancer death among women. A woman’s survival often hinges on doctors detecting the tumor before it has spread beyond the ovary. Unfortunately, most women with ovarian cancer are not diagnosed until they have symptoms – such as pelvic pain, bloating, swelling of the abdomen or appetite loss. By then, the disease has usually spread and is difficult to treat. There is currently no reliable test to diagnose ovarian cancer before symptoms emerge. Some tests measure proteins in the blood or use ultrasound images to identify ovary tumors. These tests usually still identify the disease too late. Sometimes they produce “false positive” results, which may cause women without cancer to undergo unnecessary surgery.
Many ovarian cancers have defects in small pieces of genetic information called microRNAs. These microRNAs impact the tumor in multiple ways, and cells release microRNAs into the blood. Testing a seemingly healthy women’s blood for the same pattern of altered microRNAs found in women with ovarian cancer might be one way to detect the disease earlier.
Now, Elias et al. have identified a pattern of seven microRNAs in the blood that appears to predict ovarian cancer. In the experiments, a computer program searched for microRNA patterns in women with ovarian cancer. The program sifted through the microRNAs in blood from women with and without ovarian cancer. Over time, the computer program “learned” to identify a pattern of microRNAs found only in women with ovarian cancer. It then created a formula for identifying ovarian cancer based on seven of the microRNAs.
Elias et al. then verified that the formula accurately detected ovarian cancer by testing it on blood samples from more women with and without cancer. They also found the seven microRNAs in tiny ovarian cancer tumors collected from women. This suggests the formula might be able to detect even the smallest tumors. More studies are needed to determine when this cancer-linked pattern first emerges and confirm that this ovarian cancer-detection formula works. If the test is validated, it might be used to screen women who are at high risk for ovarian cancer because of mutations in the BRCA1 and BRCA2 genes.
Journal Article
Cloning and variation of ground state intestinal stem cells
by
Chevalier, Benoit
,
Devers, Thomas
,
Ho, Khek Yu
in
13/100
,
631/532/2118/2437
,
Bacterial Toxins - pharmacology
2015
Stem cells of the gastrointestinal tract, pancreas, liver and other columnar epithelia collectively resist cloning in their elemental states. Here we demonstrate the cloning and propagation of highly clonogenic, ‘ground state’ stem cells of the human intestine and colon. We show that derived stem-cell pedigrees sustain limited copy number and sequence variation despite extensive serial passaging and display exquisitely precise, cell-autonomous commitment to epithelial differentiation consistent with their origins along the intestinal tract. This developmentally patterned and epigenetically maintained commitment of stem cells is likely to enforce the functional specificity of the adult intestinal tract. Using clonally derived colonic epithelia, we show that toxins A or B of the enteric pathogen
Clostridium difficile
recapitulate the salient features of pseudomembranous colitis. The stability of the epigenetic commitment programs of these stem cells, coupled with their unlimited replicative expansion and maintained clonogenicity, suggests certain advantages for their use in disease modelling and regenerative medicine.
Novel technology to rapidly clone patient-specific, ‘ground state’ stem cells of columnar epithelia reveals their proliferative potential, remarkably precise and origin-dependent lineage commitment as well as genomic stability, despite extensive culturing, thereby skirting limitations associated with pluripotent stem cells.
Isolated intestinal stem cells
Although it is possible to grow intestinal organoids that contain a percentage of intestinal stem cells in culture, to date it has not been possible to isolate and establish clones of human intestinal cells. Frank McKeon and colleagues have now isolated clones with stem cell properties from distinct regions of the human intestine and colon. The cells are stably maintained over several generations in culture with no changes to their genomic properties, and differentiate into specialized cell types that reflect their site of origin along the intestinal tract. The authors demonstrate that these cloned intestinal cells can be used to assess the effect of enteric-specific pathogens, highlighting their potential for disease modelling and regenerative medicine.
Journal Article
The Utility of Immunohistochemistry in the Differential Diagnosis of Gynecologic Disorders
by
Kaspar, Hanna G.
,
Crum, Christopher P.
in
Biomarkers - analysis
,
Biomarkers, Tumor - analysis
,
Diagnosis, Differential
2015
Immunohistochemistry has assumed an increasing role in the identification and characterization of gynecologic disorders including lesions with deceptively bland morphology, uncommon and underdiagnosed neoplasms, and neoplasms with specific genetic alterations associated with overexpression or loss of expression of specific proteins. The diagnostic accuracy has been significantly improved owing to the discovery and increasing experience with the tumor-associated biomarkers, and the increasing demand for precise tumor classification to assess suitability for the expanding therapeutic modalities including clinical trials.
To differentiate lesions of the gynecologic tract through the use of effective immunohistochemical panels.
Literature review and authors' personal practice experience.
The application of diagnostic and prognostic immunohistochemical panels has enabled pathologists to better guide therapeutic decisions and to better predict the clinical outcome. It is now well established that the use of ancillary testing, including immunohistochemistry, has a significant power in the identification, differentiation, and classification of reactive, premalignant, and malignant gynecologic disorders. This article discusses the utilities and pitfalls of the commonly used immunohistochemical markers in the context of overlapping morphologic features encountered in the uterus, ovaries, and fallopian tubes.
Journal Article
Microanatomy of the cervical and anorectal squamocolumnar junctions: a proposed model for anatomical differences in HPV-related cancer risk
2015
Human papilloma virus (HPV) infection causes cancers and their precursors (high-grade squamous intraepithelial lesions) near cervical and anal squamocolumnar junctions. Recently described cervical squamocolumnar junction cells are putative residual embryonic cells near the cervical transformation zone. These cells appear multipotential and share an identical immunophenotype (strongly CK7-positive) with over 90% of high-grade squamous intraepithelial lesions and cervical carcinomas. However, because the number of new cervical cancers discovered yearly world wide is 17-fold that of anal cancer, we posed the hypothesis that this difference in cancer risk reflects differences in the transition zones at the two sites. The microanatomy of the normal anal transformation zone (
n
=37) and topography and immunophenotype of anal squamous neoplasms (
n
=97) were studied. A discrete anal transition zone was composed of multilayered CK7-positive/p63-negative superficial columnar cells and an uninterrupted layer of CK7-negative/p63-positive basal cells. The CK7-negative/p63-positive basal cells were continuous with—and identical in appearance to—the basal cells of the mature squamous epithelium. This was in contrast to the cervical squamocolumnar junction, which harbored a single-layered CK7-positive/p63-negative squamocolumnar junction cell population. Of the 97 anal intraepithelial neoplasia/squamous cell carcinomas evaluated, only 27% (26/97) appeared to originate near the anal transition zone and only 23% (22/97) were CK7-positive. This study thus reveals two fundamental differences between the anus and the cervix: (1) the anal transition zone does not harbor a single monolayer of residual undifferentiated embryonic cells and (2) the dominant tumor immunophenotype is in keeping with an origin in metaplastic (CK7-negative) squamous rather than squamocolumnar junction (CK7-positive) epithelium. The implication is that, at birth, the embryonic cells in the anal transition zone have already begun to differentiate, presenting a metaplasia that—similar to vaginal and vulvar epithelium—is less prone to HPV-directed carcinogenesis. This in turn underscores the link between cancer risk and a very small and discrete population of vulnerable squamocolumnar junction cells in the cervix.
Journal Article