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Gynecologic Oncology | 2012

Impact of the new FIGO 2009 staging classification for vulvar cancer on prognosis and stage distribution

Zaid M. Tabbaa; Jesus Gonzalez; Jacek J. Sznurkowski; Amy L. Weaver; Andrea Mariani; William A. Cliby

OBJECTIVE In 2009, FIGO modified staging of vulvar cancer--the performance of the new classification relative to the prior system has not been assessed. We sought to investigate the impact of the 2009 FIGO vulvar cancer staging system on stage distribution and prognostic ability of the 2009 sub-stage classifications in a large cohort of uniformly staged cases with long-term followup. METHODS Patients undergoing surgery for vulvar cancer were identified from 2 institutions (Mayo Clinic and Medical University, Gdansk, Poland) using a similar surgical approach. Inclusion criteria required primary surgery for invasive vulvar cancer for cases with >1 mm invasion with complete inguinal/femoral lymphadenectomy. The technique of inguinofemoral node dissection used in both institutions was designed to remove both superficial and deep inguinofemoral nodes. A retrospective review was performed and all cases were assigned stage using the 1988 and 2009 FIGO systems after reviewing pathology slides. Cause-specific survival (CSS, death due to cancer) was estimated using the Kaplan-Meier method and compared using the Cox proportional hazards model t for the first 10 years after surgery. RESULT A total of 468 patients met inclusion criteria. Thirty-one percent (n=155) were down-staged, and 1 case up-staged using 2009 staging. The new system fails to effectively separate 10-yr CSS for stage I and II cases (p=0.52), while FIGO 1988 failed to separate stages II and III (p=0.41). We observed a difference in survival for stage I and II cases based on tumor diameter. For smaller stage II lesion (≤4 cm vs. >4 cm) we observed no difference in survival compared to all stage IB cases (p=0.25) Considering node positive disease, patients with 2009 FIGO stages ΙΙΙA, ΙΙΙB, and ΙΙΙC were not significantly different in terms of CSS (p=0.17). However, CSS approached significance between patients with extracapsular vs. intracapsular disease (p=0.072). For stages IIIA and IIIB (excluding extracapsular spread, IIIC), we observed that the number of positive nodes and diameter of lymph node metastasis were not significantly associated with CSS. When comparing bilateral nodal involvement vs. unilateral cases with at least 2 involved nodes, we found no statistical difference in CSS (p=0.30). CONCLUSION This is the largest cohort study to evaluate the effect and prognostic performance of the new FIGO vulvar cancer staging system. The new staging does not stratify survival between stages I and II and reduces CSS in stage I cases. Our results suggest that lesion size in node negative cases is an important prognostic variable that could be addressed in future staging classifications. Among the node positive cases, the current classification results in slight differences in CSS, primarily between intra- and extra-capsular disease and not according to the number of positive nodes and lymph node metastasis diameter. Finally we observe that bilateral nodal disease does not appear to impact CSS, justifying it being omitted from the 2009 staging system and that separating node positive (2009 stage III) from node negative (2009 stage II) cases is justified.


PLOS ONE | 2013

A Novel Role of the Sp/KLF Transcription Factor KLF11 in Arresting Progression of Endometriosis

Gaurang S. Daftary; Ye Zheng; Zaid M. Tabbaa; John K. Schoolmeester; R.P. Gada; Adrienne Grzenda; Angela Mathison; Gary L. Keeney; Gwen Lomberk; Raul Urrutia

Endometriosis affects approximately 10% of young, reproductive-aged women. Disease associated pelvic pain; infertility and sexual dysfunction have a significant adverse clinical, social and financial impact. As precise disease etiology has remained elusive, current therapeutic strategies are empiric, unfocused and often unsatisfactory. Lack of a suitable genetic model has impaired further translational research in the field. In this study, we evaluated the role of the Sp/KLF transcription factor KLF11/Klf11 in the pathogenesis of endometriosis. KLF11, a human disease-associated gene is etiologically implicated in diabetes, uterine fibroids and cancer. We found that KLF11 expression was diminished in human endometriosis implants and further investigated its pathogenic role in Klf11-/- knockout mice with surgically induced endometriotic lesions. Lesions in Klf11-/- animals were large and associated with prolific fibrotic adhesions resembling advanced human disease in contrast to wildtype controls. To determine phenotype-specificity, endometriosis was also generated in Klf9-/- animals. Unlike in Klf11-/- mice, lesions in Klf9-/- animals were neither large, nor associated with a significant fibrotic response. KLF11 also bound to specific elements located in the promoter regions of key fibrosis-related genes from the Collagen, MMP and TGF-β families in endometrial stromal cells. KLF11 binding resulted in transcriptional repression of these genes. In summary, we identify a novel pathogenic role for KLF11 in preventing de novo disease-associated fibrosis in endometriosis. Our model validates in vivo the phenotypic consequences of dysregulated Klf11 signaling. Additionally, it provides a robust means not only for further detailed mechanistic investigation but also the ability to test any emergent translational ramifications thereof, so as to expand the scope and capability for treatment of endometriosis.


Endocrinology | 2014

Epigenetic Regulation of Uterine Biology by Transcription Factor KLF11 via Posttranslational Histone Deacetylation of Cytochrome p450 Metabolic Enzymes

Ye Zheng; Zaid M. Tabbaa; Z. Khan; John K. Schoolmeester; Sherif A. El-Nashar; Abimbola O. Famuyide; Gary L. Keeney; Gaurang S. Daftary

Endocrine regulation of uterine biology is critical for embryo receptivity and human reproduction. Uterine endometrium depends on extrinsic sex steroid input and hence likely has mechanisms that enable adaptation to hormonal variation. Emerging evidence suggests that sex steroid bioavailability in the endometrium is determined by adjusting their metabolic rate and fate via regulation of cytochrome (CYP) p450 enzymes. The CYP enzymes are targeted by ubiquitously expressed Sp/Krüppel-like (Sp/KLF) transcription factors. Specifically, KLF11 is highly expressed in reproductive tissues, regulates an array of endocrine/metabolic pathways via epigenetic histone-based mechanisms and, when aberrantly expressed, is associated with diabetes and reproductive tract diseases, such as leiomyoma and endometriosis. Using KLF11 as a model to investigate epigenetic regulation of endometrial first-pass metabolism, we evaluated the expression of a comprehensive array of metabolic enzymes in Ishikawa cells. KLF11 repressed most endometrial CYP enzymes. To characterize KLF11-recruited epigenetic regulatory mechanisms, we focused on the estrogen-metabolizing enzyme CYP3A4. KLF11 expression declined in secretory phase endometrial epithelium associated with increased CYP3A4 expression. Additionally, KLF11 bound to CYP3A4 promoter GC elements and thereby repressed promoter, message, protein as well as enzymatic function. This repression was epigenetically mediated, because KLF11 colocalized with and recruited the corepressor SIN3A/histone deacetylase resulting in selective deacetylation of the CYP3A4 promoter. Repression was reversed by a mutation in KLF11 that abrogated cofactor recruitment and binding. This repression was also pharmacologically reversible with an histone deacetylase inhibitor. Pharmacological alteration of endometrial metabolism could have long-term translational implications on human reproduction and uterine disease.


Fertility and Sterility | 2014

Unilateral oophorectomy results in compensatory follicular recruitment in the remaining ovary at time of ovarian stimulation for in vitro fertilization.

Z. Khan; R.P. Gada; Zaid M. Tabbaa; Shannon K. Laughlin-Tommaso; Jani R. Jensen; Charles C. Coddington; Elizabeth A. Stewart

OBJECTIVE To assess the effect of unilateral oophorectomy (UO) by assessing ovarian reserve (OVR) and the response to gonadotropin stimulation in women with UO undergoing in vitro fertilization (IVF) compared with the response of the ipsilateral ovary of women without UO. DESIGN Historical cohort study. SETTING Academic fertility clinic. PATIENT(S) Fifty-one women with single ovary compared with a referent group with both ovaries in a 1:2 fashion. INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) Day-3 follicle-stimulating hormone (FSH), estradiol, and antral follicle counts as measures of OVR, and IVF outcomes including number of follicles aspirated and oocytes retrieved. RESULT(S) The baseline demographics and serum markers of OVR were not different. Referent women had greater follicular yield and oocyte numbers when compared with women with UO; however, when compared with the ipsilateral ovary of the referents, women with UO had a higher antral follicle count and greater follicle and oocyte numbers. In multivariate analyses, the ovary from women with UO was more likely to yield more than the median number of follicles and oocytes than the ipsilateral ovary in referent women. Live-birth rates in both groups were similar. CONCLUSION(S) Our results suggest that the remaining ovary appears to compensate in follicular yield after UO in women, confirming the animal data. Women with UO can be reassured and appropriately counseled regarding IVF.


Reproductive Sciences | 2014

KLF11 epigenetically regulates glycodelin-A, a marker of endometrial biology via histone-modifying chromatin mechanisms.

Zaid M. Tabbaa; Ye Zheng; Gaurang S. Daftary

Endometrial biology is characterized by programmed proliferation and differentiation that is synchronous with ovarian folliculogenesis to maximize the chance of pregnancy. Glycodelin-A, an endometrial secretory protein, promotes pregnancy mostly through immunomodulatory mechanisms. Glycodelin-A is repressed during the proliferative and early secretory phase and activated thereafter. Progesterone activates glycodelin via the Sp1 (Specificity Protein 1) transactivator. We identify a novel role for Kruppel-like transcription factor 11 (KLF11) as a glycodelin-A repressor. Although KLF11 bound 2 distinct regulatory elements, it regulated glycodelin promoter activity differentially through each element. Whereas KLF11 weakly activated glycodelin promoter activity via a region that also bound Sp1, the dominant effect of KLF11 was repression of promoter activity, messenger RNA (mRNA), and protein expression via a novel, specific binding element. KLF11 mediated this repression by recruiting the SIN3/histone deacetylase (HDAC) corepressor complex to the glycodelin promoter. KLF11 may solely, or by competing with Sp1, repress glycodelin-A levels and thereby influence its role in the endometrium.


Gynecologic Oncology | 2014

Short-term outcomes after incontinent conduit for gynecologic cancer: Comparison of ileal, sigmoid, and transverse colon

Zaid M. Tabbaa; Jo Marie Tran Janco; Andrea Mariani; Sean C. Dowdy; Michaela E. McGree; Amy L. Weaver; William A. Cliby

OBJECTIVE The aim of this study is to estimate the overall rates of significant incontinent conduit-related complications and compare rates between conduit types. METHODS This was a retrospective review of 166 patients who underwent incontinent urinary diversion from April 1993 through April 2013. Patients were categorized by conduit type-ileal, sigmoid colon, and transverse colon. Significant conduit-related complications were assessed at 30 and 90days after surgery. Significant conduit-related complication was defined as any of the following: ureteral stricture, conduit leak, conduit obstruction, conduit ischemia, ureteral anastomotic leak, stent obstruction requiring intervention via interventional radiology procedure or reoperation, and renal failure. RESULTS A total of 166 patients underwent formation of an incontinent urinary conduit, most commonly during exenteration for gynecologic malignancy. There were 129 ileal, 11 transverse colon, and 26 sigmoid conduits. The overall significant conduit-related complication rate within 30days was 15.1%. Complication rates for ileal, transverse and sigmoid conduits were 14.7%, 0%, and 23.1%, respectively (Fishers exact test, p=0.24). By 90days, the Kaplan-Meier estimated rates of significant complications were 21.8% overall, and 22.3%, 0%, and 28.9%, respectively, by conduit type (log-rank test, p=0.19). The most common significant conduit-related complications were conduit or ureteral anastomotic leaks and conduit obstructions. By 1 and 2years following surgery, the Kaplan-Meier estimated overall rate of significant conduit-related complication increased to 26.5% and 30.1%, respectively. CONCLUSIONS Our study suggests that there are multiple appropriate tissue sites for use in incontinent conduit formation, and surgical approach should be individualized. Most significant conduit-related complications occur within 90days after surgery.


Fertility and Sterility | 2013

Dynamic regulation of endometrial physiology and metabolism by the human disease gene klf11 via epigenetic histone mediated modulation of cytochrome P450 genes

Zaid M. Tabbaa; Ye Zheng; Z. Khan; Gaurang S. Daftary


Gynecologic Oncology | 2012

Prognostic significance of tumor DNA ploidy in intermediate-risk endometrioid endometrial cancer: A study of 1053 patients from a tertiary referral center

Zaid M. Tabbaa; Sean C. Dowdy; Karl C. Podratz; Jamie N. Bakkum-Gamez; William A. Cliby; Sanjeev Kumar; Gary L. Keeney; Amy L. Weaver; Michaela E. McGree; Andrea Mariani


Gynecologic Oncology | 2012

Impact of neoadjuvant chemotherapy (NACT) on nutritional status and treatment-related morbidity in medically unfit women with advanced ovarian cancer (AOC)

Gretchen Glaser; L. Hartman; William A. Cliby; Michelle L. Torres; Zaid M. Tabbaa; Kimberly R. Kalli; Amy L. Weaver; Aminah Jatoi; Andrea Mariani


Fertility and Sterility | 2012

The Predictive Value of Antral Follicle Count (AFC) At Down Regulation Prior to IVF Stimulation is Better Than A Diagnostic AFC

R.P. Gada; Phoebe H. Leonard; Adrienne Grzenda; A. Asante; Zaid M. Tabbaa; Charles C. Coddington; Gaurang S. Daftary

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