Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Christina Isacson is active.

Publication


Featured researches published by Christina Isacson.


The American Journal of Surgical Pathology | 2007

Ovarian mucinous tumors associated with mature cystic teratomas: Morphologic and immunohistochemical analysis identifies a subset of potential teratomatous origin that shares features of lower gastrointestinal tract mucinous tumors more commonly encountered as secondary tumors in the ovary

Russell Vang; Allen M. Gown; Chengquan Zhao; Todd S. Barry; Christina Isacson; Mary S. Richardson; Brigitte M. Ronnett

Most primary ovarian mucinous tumors are of surface epithelial-stromal origin and exhibit diffuse expression of cytokeratin 7 (CK7) combined with variable expression of cytokeratin 20 (CK20); this immunoprofile distinguishes them from most lower gastrointestinal tract tumors secondarily involving the ovaries. The uncommon ovarian mucinous tumors of germ cell (teratomatous) origin have not been extensively evaluated to determine the utility of these markers and other markers of intestinal differentiation for distinguishing these tumors from metastatic gastrointestinal tract mucinous tumors. Immunohistochemical expression of CK7, CK20, CDX2, and villin was assessed in 44 ovarian mucinous tumors associated with a mature cystic teratoma. All cases lacked evidence of a nonovarian primary mucinous tumor. All mucinous tumors were unilateral; 6 cases had bilateral teratomas. All tumors displayed gastrointestinal-type mucinous differentiation, with epithelium that was commonly goblet cell-rich or hypermucinous; 21 were associated with pseudomyxoma ovarii and 3 of these had pseudomyxoma peritonei. Tumor architecture ranged from purely cystadenomatous (n=24), to proliferative (n=13), to carcinomatous (n=6); some tumors had admixtures of these patterns. One tumor had a goblet cell carcinoidlike pattern with pseudomyxoma ovarii. Three carcinomas had a signet ring cell component. Cystadenomatous tumors without pseudomyxoma ovarii (n=15) exhibited all possible CK7/CK20 coordinate expression profiles with nearly equal frequency. All proliferative tumors without pseudomyxoma ovarii (n=8) expressed CK7, most often in combination with CK20 expression. All cystadenomatous and proliferative tumors with pseudomyxoma ovarii (n=9 and n=5) were CK7−/CK20+. All carcinomatous tumors had pseudomyxoma ovarii; 3 were CK7−/CK20+, 2 were CK7+/CK20+, and 1 was CK7+/CK20−. The presence of pseudomyxoma ovarii was significantly associated with a CK7−/CK20+ profile (86% with pseudomyxoma ovarii vs. 13% without, P<0.0001), CDX2 positivity (79% vs. 0%, P<0.0001), and villin positivity (57% vs. 5%, P=0.0009). A subset of mucinous tumors associated with mature cystic teratomas exhibiting morphologic and immunohistochemical features of lower intestinal tract-type mucinous tumors may be teratomatous in origin. In practice, the more common diagnosis of secondary involvement by a lower intestinal tract mucinous tumor should be addressed in the pathology report and in subsequent clinical evaluation; interpretation as a true primary ovarian mucinous tumor of teratomatous origin can be considered as an alternative diagnosis when evaluation and follow-up fail to identify a nonovarian source of the mucinous tumor. Those tumors having CK7 expression with or without CK20 expression may be derived from upper gastrointestinal tract-type or sinonasal-type teratomatous elements but could be independent tumors of surface epithelial-stromal origin.


The American Journal of Surgical Pathology | 2000

Endometrial intraepithelial carcinoma with associated peritoneal carcinomatosis

Robert A. Soslow; Edyta C. Pirog; Christina Isacson

Endometrial intraepithelial carcinoma (EIC) is a recently described entity, defined as a noninvasive, cytologically malignant lesion that replaces the endometrial surface epithelium. EIC frequently coexists with uterine serous carcinoma (USC) and is hypothesized to be its precursor lesion. However, the clinical significance and biologic potential of finding EIC without USC is not known. We report three postmenopausal women with EIC alone who were found to have multiple, synchronous foci of extrauterine serous carcinoma at presentation. Because the clinical findings in these patients simulated primary peritoneal serous carcinoma (PSC), we compared the clinicopathologic features of these cases with a group of nine bona fide PSCs for which exhaustively sectioned endometria, fallopian tubes, and ovaries were available for review. The average age of the EIC patients was 73 years. Two patients presented with abdominal distention and one with vaginal bleeding. Hysterectomy in each case showed endometrial polyps with EIC, but without invasive USC, in a background of atrophic endometrium. Bilateral salpingo-oophorectomy and staging showed serous carcinoma involving the ovarian hilum, the surfaces of the fallopian tubes and ovaries, in addition to peritoneal carcinomatosis. p53 overexpression was observed in both EIC and the extrauterine deposits of serous carcinoma in each case. The average age of the PSC patients was 66 years. All nine patients presented with abdominal distention. EIC was not identified in any of the hysterectomy specimens. Bilateral salpingo-oophorectomies, omentectomies, and peritoneal biopsies showed peritoneal carcinomatosis, including bulky peritoneal tumor deposits, but only minimal ovarian surface involvement. p53 overexpression was observed in seven cases. These findings indicate that EIC without coincident USC can be associated with invasive, extrauterine serous carcinomatosis. We did not, however, find any significant differences between the clinicopathologic features of primary extrauterine serous carcinomas (PSCs) and those associated with EIC. We conclude that the finding of EIC in an endometrial curettage specimen should prompt a thorough search for an invasive uterine and/or extrauterine serous carcinoma. Conversely, an endometrial origin should be excluded in patients with peritoneal carcinomatosis.


The American Journal of Surgical Pathology | 2002

Diagnostic Accuracy of Cervical Low-Grade Squamous Intraepithelial Lesions Is Improved With MIB-1 Immunostaining.

Edyta C. Pirog; Rebecca N. Baergen; Robert A. Soslow; Diane Tam; Amy E. Demattia; Yao-Tseng Chen; Christina Isacson

There is considerable interobserver variation in the diagnosis of low-grade squamous intraepithelial lesion that involves mature squamous epithelium. Our aim was to evaluate the utility of MIB-1 immunostaining as an adjunct test to increase diagnostic accuracy. Consecutive cervical biopsies originally diagnosed as normal (n = 26) or low-grade squamous intraepithelial lesion (n = 23) were reviewed by three pathologists to obtain a consensus diagnosis. MIB-1 immunostaining was performed, and positive staining was defined as a cluster of at least two stained nuclei in the upper two thirds of the epithelial thickness. Human papillomavirus (HPV) DNA detection was performed using a polymerase chain reaction assay. All cases were subsequently reclassified as low-grade squamous intraepithelial lesion (LSIL) or normal (NL) when two or three of three gold standard criteria were satisfied (LSIL gold standard criteria = consensus diagnosis of LSIL, HPV+, MIB-1+; NL gold standard criteria = consensus diagnosis of NL, HPV−, MIB-1−). Using the gold standard diagnoses, we have identified that 14 normal cases (36%) were originally overdiagnosed as LSIL, and one LSIL case (10%) was originally underdiagnosed as normal. All MIB-1-positive cases were HPV+ and identified as LSIL in the consensus review. All MIB-1-negative cases were NL by gold standard criteria. The sensitivity (1.0) and the specificity (1.0) of MIB-1 staining for identifying LSIL were superior to the sensitivity (0.9) and the specificity (0.8) of HPV testing. In conclusion, MIB-1 is a highly sensitive and specific marker for identifying low-grade squamous intraepithelial lesion and is helpful in verifying the diagnosis of equivocal cases.


International Journal of Gynecological Pathology | 2001

Early uterine serous carcinoma: clonal origin of extrauterine disease.

Rebecca N. Baergen; Cheryl D. Warren; Christina Isacson; Lora Hedrick Ellenson

Uterine serous carcinoma (USC) is an uncommon but aggressive type of endometrial carcinoma that is frequently associated with extrauterine disease despite minimal or no myometrial invasion. The origin of the extrauterine tumors in this setting remains controversial. The majority of USCs (90%) and endometrial intraepithelial carcinomas (78%), the putative precursor of USC, have p53 mutations, suggesting that p53 alterations occur early in the pathogenesis of USC. To determine if the extrauterine tumors associated with minimally invasive USC and endometrial intraepithelial carcinoma (EIC) represent metastases or multifocal primary tumors, we examined the mutational pattern of the p53 gene in 3 cases of minimally invasive USC and 1 case of EIC and in the corresponding extrauterine tumors associated with each of the cases. In all 4 cases, the primary tumors and the associated extrauterine tumor foci had identical p53 mutations. Our results support the premise that extrauterine serous tumors found in association with EIC or minimally invasive USC represent a unifocal process and thus are early metastases.


Modern Pathology | 2004

Molecular characterization of uterine clear cell carcinoma

Hee-Jung An; Sanjay Logani; Christina Isacson; Lora Hedrick Ellenson

Clinicopathological studies support a broad classification of endometrial carcinoma into two major types, designated as type I and type II, which correlate with their biological behavior. More recently, molecular studies have provided further insights into this classification scheme by elucidating the genetic events involved in the development and progression of endometrial carcinoma. Microsatellite instability and mutations in the PTEN gene have been widely associated with type I (endometrioid) endometrial carcinoma, while p53 mutations have been identified in the majority of type II endometrial carcinoma, of which uterine serous carcinoma is the prototype. Uterine clear cell carcinoma (UCC) is an uncommon variant of endometrial carcinoma, and clinicopathological studies have produced conflicting results regarding its biological behavior with 5-year survival ranging from 21 to 75%. The molecular characteristics of endometrioid and serous carcinoma have been studied extensively; however, there have been few molecular genetic studies of the clear cell subtype. In this study, we evaluated 16 UCCs (11 pure and 5 mixed) for mutations in the p53 gene, PTEN gene and for microsatellite instability. Although we found that these alterations were uncommon in pure clear cell carcinomas, all three were identified. In addition, two cases of mixed serous and clear cell carcinoma showed an identical mutation of the p53 gene in the histologically distinct components and one case of mixed clear cell and endometrioid carcinoma had identical mutations in the PTEN and p53 genes, and microsatellite instability in both components. Our data suggest that UCC represent a heterogeneous group of tumors that arise via different pathogenetic pathways. Additional molecular studies of pure clear cell carcinoma are required to further elucidate the genetic pathways involved in its development and progression.


The American Journal of Surgical Pathology | 2002

A comparative analysis of 57 serous borderline tumors with and without a noninvasive micropapillary component.

Brian M. Slomovitz; Thomas A. Caputo; Herbert Gretz; Katherine Economos; Drew V. Tortoriello; Peter W. Schlosshauer; Rebecca N. Baergen; Christina Isacson; Robert A. Soslow

The literature concerning serous borderline tumors with a noninvasive micropapillary component suggests an association with invasive implants. We compared the clinicopathologic features of micropapillary serous borderline tumors (MSBTs) with typical SBTs to determine the following: 1) the importance of focal micropapillary architecture in an otherwise typical SBT, 2) the behavior of low-stage MSBTs, 3) whether high-stage MSBTs are inherently more aggressive than high-stage SBTs, and 4) whether invasive implants are prevalent in an MSBT cohort without referral selection bias. The 57 borderline tumors studied were diagnosed at a university hospital between 1981 and 1998; they included 14 MSBTs, 35 SBTs, and 8 SBTs with focal micropapillary features. None of the specimens were referrals for expert pathologic consultation, thus distinguishing our study group from most of those previously reported. Neither MSBTs nor SBTs were associated with invasive implants at diagnosis (0 of 14 and 0 of 43, respectively). They also did not differ with respect to overall stage at diagnosis, but MSBTs were more frequently bilateral than SBTs (71% versus 23%, p = 0.001). There was an increased risk of recurrence in MSBT versus SBT (3 of 14 versus 1 of 43, p = 0.035), but this was stage related; there was no difference between groups when evaluating recurrence in stage I disease (0 of 8 versus 0 of 27). There was no difference in recurrence or stage at diagnosis between SBTs with focal micropapillary features and other SBTs. There was 100% survival in all groups. We conclude that high-stage MSBTs with noninvasive implants should be considered a subtype of SBTs with an increased risk of recurrence. Stage I MSBTs demonstrate clinical features that are similar to low-stage SBTs. Focal micropapillary architecture (<5 mm) has no bearing on outcome. MSBTs in the general population are not strongly associated with invasive implants.


International Journal of Gynecological Pathology | 1998

Distinctive p53 and mdm2 immunohistochemical expression profiles suggest different pathogenetic pathways in poorly differentiated endometrial carcinoma.

Robert A. Soslow; Peter U-Fu Shen; Marilda H. Chung; Christina Isacson

SummaryEndometrial serous carcinoma (ESC) and FIGO (International Federation of Gynecology and Obstetrics) grade 3 endometrioid adenocarcinoma (EC) are high-grade endometrial tumors that have different clinical and morphologic attributes. Alteration of p53 tumor suppressor protein function has been implicated in the pathogenesis of both tumors, although the mechanisms may differ. We sought to investigate this difference by comparing immunohistochemical expression of p53 and mdm2. p53 immunoreactivity often correlates with gene mutation, whereas increased mdm2 expression is linked to complex formation with wild-type p53 resulting in its inactivation. Twenty cases of ESC and 21 cases of EC were evaluated and an immunoreactivity score (IRS) was assigned using both the percentage of cells stained and the intensity of staining. The overall IRSs were significantly different in ESCs versus ECs for both p53 and mdm2 (p <0.001 and p <0.01, respectively). Strong mean immunoreactivity for p53 was detected in 15 (75%) ESCs as compared to only weak mean immunoreactivity in 17 (81%) ECs. Conversely, for mdm2 expression, 17 (81%) ECs had moderate mean immunoreactivity whereas 9 (45%) ESCs showed only weak mean immunoreactivity. mdm2 expression more closely correlated with p53 expression in ECs than in ESCs. In ECs, mdm2 was detected in 16 of 17 (94%) p53-positive tumors but in only 1 of 3 (33%) p53-negative tumors (p <0.025). In ESCs, mdm2 was detected in 9 of 15 (60%) p53-positive tumors but in none of the 5 p53-negative tumors (p <0.10). Overall, our results demonstrate an inverse relationship between the expression of p53 and mdm2 in ESC versus high-grade EC. Specifically, strong p53 immunoreactivity is associated with weak mdm2 expression in ESC and weak p53 expression is associated with moderate mdm2 expression in EC. These results suggest different pathogenetic pathways resulting in loss of normal p53 function in these two tumors: by p53 gene mutation (strong p53 overexpression) in ESCs, or by mdm2 complex formation and inactivation of p53 in high-grade ECs.


Cancer | 2009

Phase II trial of neoadjuvant docetaxel and gefitinib followed by radical prostatectomy in patients with high‐risk, locally advanced prostate cancer

Jacqueline Vuky; Christopher R. Porter; Christina Isacson; Matthew Vaughan; Paul M. Kozlowski; Vincent J. Picozzi; John M. Corman

Prostate cancer trials investigating neoadjuvant hormonal therapy, followed by surgery, have demonstrated that elimination of all tumor cells from the primary site is rare. The authors report a phase 2 trial assessing the efficacy and toxicity of docetaxel and gefitinib in patients with high‐risk localized prostate cancer as neoadjuvant therapy before radical prostatectomy (RP).


International Journal of Gynecological Pathology | 2000

Cyclin D1 expression in high-grade endometrial carcinomas--association with histologic subtype.

Robert A. Soslow; Peter U-Fu Shen; Marilda H. Chung; Christina Isacson; Rebecca N. Baergen

Endometrial endometrioid adenocarcinoma (EC) and serous carcinoma (ESC) are associated with different epidemiologic risk factors, precursor lesions, morphology, and survival outcomes. They also possess distinct molecular profiles. We investigated the expression of cyclin D1, a member of the G1 cyclin family that regulates the G1/S transition in the cell cycle, and estrogen and progesterone receptors (ERs and PRs, respectively) in a group of ECs and ESCs matched for histological grade. We also sought to correlate the expression of cyclin D1 with ER and PR because cyclin D1 has been reported to stimulate transcription of ER-and PR-regulated genes (1,2). We hypothesize that cyclin D1 expression covaries with histologic subtype and is related to the expression of ER and PR. Twenty ESCs and 21 ECs were examined histologically and evaluated immunohistochemically for cyclin D1, ER, and PR using commercially available monoclonal antibodies in archival, formalin-fixed, and paraffin-embedded tissue. Three ESCs (15%) and 10 ECs (48%) expressed cyclin D1 (p = 0.02). Twelve ESCs (60%) and 16 ECs (76%) expressed ER, which is not significantly different. ER-positive ECs were significantly more likely to express cyclin D1 compared with ER-positive ESCs (p = 0.03), but a relationship between cyclin D1 and ER expression in EC was not found. We also did not find a significant relationship between cyclin D1 and PR expression. Therefore, cyclin D1 expression in poorly differentiated endometrial carcinomas is associated with endometrioid histology. This is consistent with pathobiologic divergence in poorly differentiated endometrial carcinomas.


International Journal of Gynecological Pathology | 2002

Proliferative activity of benign and neoplastic endocervical epithelium and correlation with HPV DNA detection

Edyta C. Pirog; Christina Isacson; Mathias J. Szabolcs; Bernhard Kleter; Wim Quint; Ralph M. Richart

Recent studies have indicated that the use of the MIB-1 immunostaining may be useful in distinguishing endocervical neoplasia from benign nonneoplastic lesions. We sought to investigate this finding further with a specific emphasis on the common benign processes that may result in a nonspecific increase of MIB-1 staining. In this study we quantified the MIB-1 immunostaining in the mucinous endocervical epithelium (n=45) and in tubal metaplasia (n=28) during the proliferative and secretory phases (hormonal influence), in the mucinous endocervical epithelium in cases of cervicitis (inflammation) (n=10), in cases with a history of a recent biopsy (regeneration) (n=15), endocervical polyps (benign growth) (n=8), in the endocervical glands adjacent to a squamous intraepithelial lesion (human papilloma virus [HPV] infection) (n=63), and in in situ and invasive cervical adenocarcinomas (n=30). All cases with increased MIB-1 staining were subsequently tested for the presence of HPV DNA. The range of MIB-1 staining in the benign endocervical epithelium was from 0% to 48% and in the neoplastic epithelium from 25% to 84%. MIB-1 staining below 10% always reflected a benign process and MIB-1 staining higher than 50% was always associated with a neoplasia. Rare benign cases (tubal metaplasia during the proliferative phase, glands adjacent to squamous intraepithelial lesions, and cases with a history of a recent biopsy) had increased MIB-1 index, which overlapped with the neoplastic cases. In conclusion, MIB-1 is a useful marker of endocervical neoplasia, although in rare cases an overlap between benign and neoplastic cases may exist.

Collaboration


Dive into the Christina Isacson's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar

Ralph H. Hruban

Johns Hopkins University School of Medicine

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Christopher R. Porter

State University of New York System

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Andrew Kalisz

University of Nebraska Medical Center

View shared research outputs
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge