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Stephen C Rubin

Publications and source records attributed to Stephen C Rubin.

At least 19 recordsLinked to original sources
PubMed2006

Case-control study of postmenopausal hormone replacement therapy and endometrial cancer.

This study evaluated recent inconsistent findings that adding progestins to postmenopausal estrogen replacement therapy protects against endometrial cancer. Using a population-based case-control study, the authors compared 511 endometrial cancer cases aged 50-79 years in the Philadelphia, Pennsylvania, region during 1999-2002 with 1,412 random-digit-dialing controls regarding postmenopausal hormone replacement therapy (HRT) use. Telephone interviews were performed with memory aids mailed in advance. An increased risk of endometrial cancer was observed among postmenopausal women using only unopposed estrogen for 3 or more years, compared with women who never used HRT (adjusted odds ratio = 3.4, 95% confidence interval (CI): 1.4, 8.3). Using combination HRT (of any duration) was associated with a substantial reduction in risk (odds ratio = 0.8, 95% CI: 0.6, 1.1). Comparing women using only combined estrogen and progestin for 3 or more years with women using only unopposed estrogen for 3 or more years, the authors found that the adjusted odds ratio was 0.2 (95% CI: 0.1, 0.6). Long-term use of unopposed estrogen is associated with increased risk for endometrial cancer, whereas combined estrogen plus progestin hormone therapy is not. Thus, if HRT is to be used in women with an intact uterus, this study confirms the benefit of adding progestins to the regimen.

Aged↗
PubMed2006

Estrogen sulfation genes, hormone replacement therapy, and endometrial cancer risk.

BACKGROUND: Unopposed estrogen replacement therapy is associated with increased risk of endometrial cancer. To investigate the mechanism of this association, we evaluated whether risk of endometrial cancer was associated with the genotypes involved in steroid hormone metabolism and the duration of exogenous hormone use. METHODS: A population-based case-control study in nine counties of the Philadelphia metropolitan area was undertaken with 502 case patients with endometrial cancer and 1326 age- and race-matched control subjects. Data regarding exogenous hormone use were obtained by interview, and genotypes of the genes COMT, CYP1A1, CYP1A2, CYP1B1, CYP3A4, PGR, SULT1A1, SULT1E1, and UGT1A1 were obtained by polymerase chain reaction techniques. Conditional logistic regression was used to examine the relationship among genotype, hormone use, and endometrial cancer risk. RESULTS: Associations were observed between the risk of endometrial cancer and genotypes of the following steroid hormone metabolism genes: CYP1A1*2C (adjusted odds ratio [OR] = 1.68, 95% confidence interval [CI] = 1.08 to 2.61); SULT1A1*3 (adjusted OR = 0.51, 95% CI = 0.29 to 0.92); and the G --> A variant in the promoter of SULT1E1 at position -64 (adjusted OR = 1.45, 95% CI = 1.06 to 1.99). We observed a statistically significant interaction between estrogen replacement therapy use and SULT1A1*2 genotype: the SULT1A1*2 allele and long-term use of estrogen replacement therapy were associated with statistically significantly higher risk of endometrial cancer (adjusted OR = 3.85, 95% CI = 1.48 to 10.00) than that of the SULT1A1*2 allele and no estrogen replacement therapy use. CONCLUSIONS: Among women with long-term use of estrogen replacement therapy or combined hormone replacement therapy, the risk of endometrial cancer may be associated with functionally relevant genotypes that regulate steroid hormone sulfation.

Aryl Hydrocarbon Hydroxylases↗
PubMed2006

A phase II trial of intraperitoneal photodynamic therapy for patients with peritoneal carcinomatosis and sarcomatosis.

PURPOSE: A previous phase I trial of i.p. photodynamic therapy established the maximally tolerated dose of Photofrin (Axcan Pharma, Birmingham, AL)-mediated photodynamic therapy and showed encouraging efficacy. The primary objectives of this phase II study were to determine the efficacy and toxicities of i.p. photodynamic therapy in patients with peritoneal carcinomatosis and sarcomatosis. EXPERIMENTAL DESIGN: Patients received Photofrin 2.5 mg/kg i.v. 48 hours before debulking surgery. Intraoperative laser light was delivered to the peritoneal surfaces of the abdomen and pelvis. The outcomes of interest were (a) complete response, (b) failure-free survival time, and (c) overall survival time. Photosensitizer levels in tumor and normal tissues were measured. RESULTS: One hundred patients were enrolled into one of three strata (33 ovarian, 37 gastrointestinal, and 30 sarcoma). Twenty-nine patients did not receive light treatment. All 100 patients had progressed by the time of statistical analysis. The median failure-free survival and overall survival by strata were ovarian, 2.1 and 20.1 months; gastrointestinal cancers, 1.8 and 11.1 months; sarcoma, 3.7 and 21.9 months. Substantial fluid shifts were observed postoperatively, and the major toxicities were related to volume overload. Two patients died in the immediate postoperative period from bleeding, sepsis, adult respiratory distress syndrome, and cardiac ischemia. CONCLUSIONS: Intraperitoneal Photofrin-mediated photodynamic therapy is feasible but does not lead to significant objective complete responses or long-term tumor control. Heterogeneity in photosensitizer uptake and tumor oxygenation, lack of tumor specificity for photosensitizer uptake, and the heterogeneity in tissue optical properties may account for the lack of efficacy observed.

Adult↗
PubMed2006

Primary lymphomas of the cervix and uterus: the University of Pennsylvania's experience and a review of the literature.

Primary lymphomas of the cervix and uterus are rare with approximately 150 cases reported in the world literature to date. Appropriate diagnosis is often delayed until the post-operative setting as clinical and radiographic presentations are non-specific. Several sub-types of lymphoma arising primarily in the cervix or uterus have been reported with diffuse large B-Cell lymphoma (DLBCL) being the most frequent. Due to the low incidence of this disease, no randomized clinical trials exist to help guide treatment. This study reports the experience of four patients with primary lymphomas of the uterus and cervix that reflect the heterogeneity of cases reported in the literature to date. The patients had a mean age at diagnosis of 46 (range 35 - 56) and presented with abnormal uterine bleeding. One patient was diagnosed by total abdominal hysterectomy (TAH), two patients were diagnosed by cervical biopsy and one patient was diagnosed by endometrial biopsy. Three patients had DLBCL and one patient had marginal zone lymphoma (MZL). All patients had stage IIE disease. Of the patients with DLBCL, one received chemotherapy followed by TAH and two received TAH followed by chemotherapy. Two of these three patients remain disease-free post-initial therapy with the third now disease-free post-salvage therapy and autologous stem cell transplant. The patient with MZL was treated with TAH alone and remains disease-free. Based on the case series and a review of available literature, primary lymphomas of the uterus or cervix are rare and require an individualized approach to treatment. In general, patients with limited stage disease should be treated with localized and systemic therapy to optimize chances of cure.

Adult↗
PubMed2005

Screening for ovarian cancer in the general population.

Screening for ovarian cancer in the general population presents several unique challenges. Without a clearly identified premalignant state, efforts have focused on detection of early stage disease. Towards this end, investigators have focused on the use of serum markers and transvaginal ultrasound. CA125 determination is the most reliable serum marker in use, and utilization of serial measurements to calculate risk of cancer appears to have greater utility than evaluation of a single value. Multimodality screening focuses on combining serial CA125 measurement with transvaginal ultrasound follow-up for those with abnormal values. Large prospective trials, such as the United Kingdom Collaborative Trial of Ovarian Cancer Screening (UKCTOCS), are currently underway to assess the impact of various screening strategies on mortality, and to evaluate feasibility, acceptability, and morbidity of screening. Future research efforts will undoubtedly focus on promising techniques to examine the serum proteosome for patterns to identify early ovarian cancer.

Aged↗
PubMed2005

Saphenous vein sparing during inguinal lymphadenectomy to reduce morbidity in patients with vulvar carcinoma.

OBJECTIVES: To compare short- and long-term morbidity associated with saphenous vein sparing versus ligation during inguinal lymphadenectomy for vulvar carcinoma. METHODS: A retrospective evaluation of patients with carcinoma of the vulva that underwent inguinal lymphadenectomy was performed. Operative reports were evaluated and patients were divided into those who had sparing of the saphenous vein versus ligation. Postoperative short- and long-term complications were compared between the two groups using Pearson chi squared analysis. RESULTS: There were a total of 49 inguinal lymphadenectomies performed on 29 patients. The saphenous vein was spared in 18 (37%) groin dissections compared to 31(63%) in which the saphenous vein was ligated. The two groups were similar in regards to clinical characteristics. All patients received closed suction drains and prophylactic antibiotics. Median number of nodes dissected was similar. Cellulitis was more common in the vein-ligated group compared to the vein-spared group (45% vs. 0%; P < 0.001). Wound breakdown occurred in 25% of dissections where the saphenous vein was ligated versus 0% in dissections where the vein was spared (P = or < 0.02). Short-term edema (< or = 6 months) was similar between vein-ligated and vein-spared groups (67% vs. 72%, P < 1.0). Subsequently, chronic lymphedema (> 6 months) persisted in 38% of the vein-ligated group compared to 11% in the vein-spared group (P < 0.05). The incidence of recurrent disease was similar in both groups (19.3 % vs. 22.2% P < 0.1). CONCLUSIONS: Routine preservation of the saphenous vein during inguinal lymphadenectomy for vulvar carcinoma may reduce the incidence of wound cellulitis, wound breakdown, and chronic lymphedema.

Cellulitis↗
PubMed2005

Phase II trial of weekly paclitaxel (80 mg/m2) in platinum and paclitaxel-resistant ovarian and primary peritoneal cancers: a Gynecologic Oncology Group study.

OBJECTIVE: To evaluate the activity of single agent weekly paclitaxel in patients with both platinum and paclitaxel (delivered every 3 weeks)-resistant ovarian cancer. METHODS: Forty-eight patients with platinum and paclitaxel-resistant ovarian cancer (defined as progression during, or recurrence < 6 months following, their prior treatment with both agents) received single agent weekly paclitaxel (80 mg/m2/week) until disease progression (assuming acceptable toxicity). Following the initial 12 weekly doses, treatment could be given for 3 weeks, with a 1 week break. RESULTS: In this chemoresistant population, the objective response rate was 20.9%. Serious adverse events were relatively uncommon (neuropathy-grade 2: 21%; grade 3: 4%; and grade 3 fatigue: 8%). CONCLUSION: The weekly administration of paclitaxel can be a useful management approach in women with both platinum and paclitaxel (given every 3 weeks)-resistant ovarian cancer. It would be appropriate to directly compare weekly to every 3-week paclitaxel delivery in the setting of primary chemotherapy of advanced ovarian cancer.

Adult↗
PubMed2005

Women with a prior diagnosis of breast cancer are not at an increased risk for subsequent colorectal cancer.

BACKGROUND: Earlier studies regarding the risk of colorectal cancer in women with a prior diagnosis of breast cancer yielded conflicting results. METHODS: A retrospective cohort study was performed using the General Practitioner Research Database of the United Kingdom. Women with a prior diagnosis of breast cancer were compared with female control patients without a prior history of breast cancer. The primary outcome was an incident diagnosis of colorectal cancer. Poisson regression analysis was utilized to assess the effects of potential confounder variables. RESULTS: The study included 17,415 breast cancer patients and 69,660 matched control patients with follow-up time in person years of 52,914 and 331,480, respectively. The relative rate of colorectal cancer among breast cancer patients was 0.80 (95% CI 0.56-1.15). The relative rate of colorectal cancer among women exposed and unexposed to tamoxifen were 0.73 (95% CI 0.49-1.08) and 1.81 (95% CI 0.85-3.85), respectively. CONCLUSION: Women with a prior diagnosis of breast cancer are not at an increased risk of colorectal cancer; these women can follow average risk screening guidelines for colorectal cancer.

Adult↗
PubMed2004

RNA interference: a potential strategy for isoform-specific phosphatidylinositol 3-kinase targeted therapy in ovarian cancer.

Phosphatidylinositol 3-kinase (PI3-kinase) is a novel intracellular transducer involved in a wide range of cancer-associated signaling pathways, which comprises various isoforms and splice variants with distinct biologic activities and clinical implications. Especially, the class Ia PI3-kinase 110 kD catalytic subunit alpha (PIK3CA) is the most important isoform in tumorigenesis and possibly, tumor angiogenesis. Several strategies have been developed to block PI3-kinase for cancer therapy; however, the approach to target specific PI3-kinase isoform has not been explored to date. In the present study, we show that RNA interference (RNAi) through small interfering (siRNA) sequences targeting PIK3CA has potential applications in isoform-specific "knock-down" of PI3-kinase. This strategy provides a novel tool to study the function of various PI3-kinase isoforms and may contribute to isoform-specific targeting of PI3-kinase in human cancer.

Animals↗
PubMed2004

Secondary surgical cytoreduction for advanced ovarian carcinoma.

BACKGROUND: We evaluated the effect of adding secondary cytoreductive surgery to postoperative chemotherapy on progression-free survival and overall survival among patients who had advanced ovarian cancer and residual tumor exceeding 1 cm in diameter after primary surgery. METHODS: Women were enrolled within six weeks after primary surgery. If, after three cycles of postoperative paclitaxel plus cisplatin, a patient had no evidence of progressive disease, she was randomly assigned to undergo secondary cytoreductive surgery followed by three more cycles of chemotherapy or three more cycles of chemotherapy alone. RESULTS: We enrolled 550 women. After completing three cycles of postoperative chemotherapy, 216 eligible patients were randomly assigned to receive secondary surgical cytoreduction followed by chemotherapy and 208 to receive chemotherapy alone. Surgery was declined by or medically contraindicated in 15 patients who were assigned to secondary surgery (7 percent). As of March 2003, 296 patients had died and 82 had progressive disease. The likelihood of progression-free survival in the group assigned to secondary surgery plus chemotherapy, as compared with the chemotherapy-alone group, was 1.07 (95 percent confidence interval, 0.87 to 1.31; P=0.54), and the relative risk of death was 0.99 (95 percent confidence interval, 0.79 to 1.24; P=0.92). CONCLUSIONS: For patients with advanced ovarian carcinoma in whom primary cytoreductive surgery was considered to be maximal, the addition of secondary cytoreductive surgery to postoperative chemotherapy with paclitaxel plus cisplatin does not improve progression-free survival or overall survival.

Adult↗
PubMed2004

Vascular leukocytes contribute to tumor vascularization.

There is no proof that hematopoietic cells contribute significantly to vasculogenesis in postnatal life. Here we report a novel leukocyte subset within ovarian carcinoma that coexpresses endothelial and dendritic cell markers. Fluorescence-activated cell sorter (FACS) analysis identified a high frequency of VE-cadherin+ CD45+ leukocytes (39% of host cells) in 10 of 10 solid tumors evaluated. This population represented less than 1% of nontumor cells in ascites and peripheral blood. At the protein level, more than 86% of these cells expressed the endothelial markers P1H12, CD34, and CD31 and leukocyte markers CD11c and major histocompatibility complex (MHC) class II. At the mRNA level, we detected TEM1, TEM7, and Thy-1, specific markers of angiogenic endothelium. Finally, this population has the capacity to generate functional blood vessels in vivo. Because of its mixed phenotype, we named this population vascular leukocytes (VLCs). Our data provide an important link between hematopoietic endothelial precursors and vascular development in postnatal life and a possible novel therapeutic target.

Animals↗
PubMed2004

Hormone replacement therapy and life expectancy after prophylactic oophorectomy in women with BRCA1/2 mutations: a decision analysis.

PURPOSE: The decision about prophylactic oophorectomy is difficult for many premenopausal women with BRCA1/2 mutations because of concerns and controversy about the use of hormone replacement therapy (HRT) after oophorectomy. PATIENTS AND METHODS: A Markov decision analytic model used the most current epidemiologic data to assess the expected outcomes of prophylactic oophorectomy with or without HRT (to age 50 years or for life) in cohorts of women with BRCA1/2 mutations. Sensitivity analyses were conducted to assess the impact of alternative assumptions about effects of HRT, effects of prophylactic oophorectomy, and risks of cancer associated with BRCA1/2 mutations. RESULTS: In our model, prophylactic oophorectomy lengthened life expectancy in women with BRCA1/2 mutations, irrespective of whether HRT was used after oophorectomy. This gain ranged from 3.34 to 4.65 years, depending on age at oophorectomy. Use of HRT after oophorectomy was associated with relatively small changes in life expectancy (+0.17 to -0.34 years) when HRT was stopped at age 50, but larger decrements in life expectancy if HRT was continued for life (-0.79 to -1.09 years). HRT was associated with a gain in life expectancy of between 0.39 and 0.79 years for mutation carriers undergoing both prophylactic mastectomy and oophorectomy. CONCLUSION: On the basis of the results of this decision analysis, we recommend that women with BRCA1/2 mutations undergo prophylactic oophorectomy after completion of childbearing, decide about short-term HRT after oophorectomy based largely on quality-of-life issues rather than life expectancy, and, if using HRT, consider discontinuing treatment at the time of expected natural menopause, approximately age 50 years.

Adult↗
PubMed2004

Delayed hemorrhage after cervical conization unmasking severe factor XI deficiency.

BACKGROUND: Factor XI deficiency, a rare bleeding disorder found most commonly in patients of Ashkenazi Jewish background, may be present in patients with a history of abnormal bleeding after elective surgery. CASE: A patient of Ashkenazi Jewish descent presented 12 days after cervical conization for adenocarcinoma in situ with severe vaginal bleeding requiring multiple transfusions and uterine artery embolization. After a thorough workup, a severe factor XI deficiency was found. The patient ultimately required modified radical hysterectomy for treatment of early cervical cancer. With appropriate perioperative management, the patient underwent abdominal surgery without further bleeding complications. CONCLUSION: Factor XI deficiency can present with severe bleeding episodes after elective surgery. Adequate preoperative assessment and perioperative management are necessary to prevent bleeding complications in these patients.

Adenocarcinoma↗
PubMed2003

The oncogene phosphatidylinositol 3'-kinase catalytic subunit alpha promotes angiogenesis via vascular endothelial growth factor in ovarian carcinoma.

The gene of phosphatidylinositol 3-kinase catalytic subunit alpha (PIK3CA) has been implicated as an oncogene in ovarian cancer [L. Shayesteh et al., Nat. Genet., 21: 99-102, 1999]. In this study, we examined the expression of PIK3CA mRNA and its p110alpha protein product in human ovarian carcinoma and investigated its role in regulating angiogenesis via vascular endothelial growth factor (VEGF). PIK3CA mRNA was detected in 66.6% of stage I and 93.9% of advanced stage ovarian cancer specimens and in all 17 ovarian cancer cell lines. PIK3CA mRNA levels were significantly higher in invasive carcinomas compared with benign and low malignant potential neoplasms (P = 0.007), but no significant difference was seen between early and advanced stage carcinomas (P = 0.812). Strong expression of immunoreactive p110alpha was detected in tumor cells and/or stroma endothelium. PIK3CA expression in vivo positively correlated, both at the mRNA and the protein level, with the expression of VEGF as well as with the extent of microvascular development. Furthermore, PIK3CA mRNA overexpression positively correlated with increased proliferation and decreased apoptosis of tumor cells in vivo. In vitro, PIK3CA expression positively correlated with the expression of VEGF in ovarian cancer cells, whereas the phosphatidylinositol 3'-kinase inhibitor Ly294002 reduced both the constitutive and inducible expression of hypoxia-inducible factor-1alpha at the mRNA and protein levels and abrogated VEGF up-regulation by glucose starvation. Furthermore, Ly294002 suppressed cell proliferation and, at higher doses, induced marked apoptosis in ovarian cancer cells. Collectively, these data strongly indicate that PIK3CA supports ovarian cancer growth through multiple and independent pathways affecting cell proliferation, apoptosis and angiogenesis, and plays an important role in ovarian cancer progression.

Apoptosis↗
PubMed2003

Tumor-derived vascular endothelial growth factor up-regulates angiopoietin-2 in host endothelium and destabilizes host vasculature, supporting angiogenesis in ovarian cancer.

Vascular remodeling in host tissues surrounding growing tumors is implicated in the successful development of tumor neovasculature. Cooperation between vascular endothelial growth factor (VEGF) and angiopoietins (Angs) is considered to be critical in this context. However, the mechanisms regulating the coordinated expression of these molecules remain, to date, elusive. In this study, we used a murine ovarian cancer angiogenesis model induced by overexpression of VEGF, as well as 52 human ovarian cancer specimens and 36 established cancer cell lines to characterize the expression and regulation of Ang-2 in the context of tumor angiogenesis. Using a combination of immunohistochemistry, laser capture microdissection and real-time quantitative reverse transcription-PCR, we showed that tumor-derived VEGF significantly up-regulated the expression of Ang-2 in host stroma endothelial cells, resulting in markedly increased Ang-2/Tie-2 mRNA copy number ratio in vivo. In vitro experiments showed that VEGF directly up-regulated Ang-2, which is mediated via VEGF receptor-2/flk-1/KDR pathway, in cultured endothelial cells through transcriptional activation rather than the enhanced mRNA stability. In human ovarian cancer, Ang-2 was primarily expressed in stroma endothelial cells and detectable in tumor cells of only 12% tumor specimens; however, it was not detected in the majority of established ovarian cancer cell lines. In addition, a significant correlation was observed between VEGF and Ang-2 mRNA expression (P < 0.01) but not between VEGF and Ang-1 or Tie-2 in human ovarian cancer specimens. In the mouse ovarian cancer model, up-regulation of Ang-2 in host stroma endothelial cells was significantly associated with pericyte loss and instability of the host vasculature surrounding the tumor. Our study suggests a novel mechanism by which tumor-derived VEGF interacts with Angs/Tie-2 system in host stroma endothelial cells and induces in a paracrine manner the remodeling of host vasculature to support angiogenesis during tumor growth.

Angiogenesis Inducing Agents↗
PubMed2003

Vector-based RNAi, a novel tool for isoform-specific knock-down of VEGF and anti-angiogenesis gene therapy of cancer.

Vascular endothelial growth factor (VEGF) carries out multifaceted functions in tumor development, and it exists as at least five isoforms with distinct biologic activities and clinical implications. Several strategies have been developed to block VEGF for cancer therapy; however, the approach to target-specific VEGF isoform(s) has not been explored to date. In the present study, we show that DNA vector-based RNA interference (RNAi), in which RNAi sequences targeting murine VEGF isoforms are inserted downstream of an RNA polymerase III promoter, has potential applications in isoform-specific "knock-down" of VEGF. Large molecular weight VEGF isoforms were specifically reduced in vitro in the presence of isoform-specific RNAi constructs. Additionally, H1 promoter may be superior to U6 promoter when used for vector-based RNAi of VEGF isoforms. This strategy provides a novel tool to study the function of various VEGF isoforms and may contribute to VEGF isoform-specific treatment in cancer.

Animals↗
PubMed2003

Intratumoral T cells, recurrence, and survival in epithelial ovarian cancer.

BACKGROUND: Although tumor-infiltrating T cells have been documented in ovarian carcinoma, a clear association with clinical outcome has not been established. METHODS: We performed immunohistochemical analysis of 186 frozen specimens from advanced-stage ovarian carcinomas to assess the distribution of tumor-infiltrating T cells and conducted outcome analyses. Molecular analyses were performed in some tumors by real-time polymerase chain reaction. RESULTS: CD3+ tumor-infiltrating T cells were detected within tumor-cell islets (intratumoral T cells) in 102 of the 186 tumors (54.8 percent); they were undetectable in 72 tumors (38.7 percent); the remaining 12 tumors (6.5 percent) could not be evaluated. There were significant differences in the distributions of progression-free survival and overall survival according to the presence or absence of intratumoral T cells (P<0.001 for both comparisons). The five-year overall survival rate was 38.0 percent among patients whose tumors contained T cells and 4.5 percent among patients whose tumors contained no T cells in islets. Significant differences in the distributions of progression-free survival and overall survival according to the presence or absence of intratumoral T cells (P<0.001 for both comparisons) were also seen among 74 patients with a complete clinical response after debulking and platinum-based chemotherapy: the five-year overall survival rate was 73.9 percent among patients whose tumors contained T cells and 11.9 percent among patients whose tumors contained no T cells in islets. The presence of intratumoral T cells independently correlated with delayed recurrence or delayed death in multivariate analysis and was associated with increased expression of interferon-gamma, interleukin-2, and lymphocyte-attracting chemokines within the tumor. The absence of intratumoral T cells was associated with increased levels of vascular endothelial growth factor. CONCLUSIONS: The presence of intratumoral T cells correlates with improved clinical outcome in advanced ovarian carcinoma.

Adult↗