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Dive into the research topics where Steven C. Plaxe is active.

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Featured researches published by Steven C. Plaxe.


Gynecologic Oncology | 2012

Cardiovascular disease is the leading cause of death among endometrial cancer patients

Kristy K. Ward; Nina R. Shah; Cheryl C. Saenz; Michael T. McHale; Edwin A. Alvarez; Steven C. Plaxe

OBJECTIVE To evaluate the causes of death among women with endometrial cancer. METHODS SEER registries from 1973-1988 were queried to perform a retrospective cohort study of women with invasive epithelial endometrial cancer. Causes of death were compared according to grade and stage. RESULTS 33,232 women with incident cases of endometrial cancer had died at the time of last follow up. Overall, women were most likely to die from cardiovascular disease (35.9%, 95% CI 35.3-36.3%), followed by other causes, other malignancies, and endometrial cancer. Women with low grade localized cancer were most likely to die of cardiovascular disease, while women with high grade advanced cancer were least likely to die of cardiovascular disease and most likely to die of endometrial cancer. For the entire population, risk of death from cardiovascular causes surpasses the risk of death from endometrial cancer 5 years after diagnosis. CONCLUSIONS Higher risk of cardiac death among endometrial cancer patients likely reflects the high probability of curative cancer treatment and the prevalence of cardiac disease and risk factors. As the probability of dying of endometrial cancer decreases with time, the probability of dying of cardiovascular disease increases. Interventions and investigations aimed at addressing risk factors for cardiovascular disease may have the greatest potential to improve survival for women diagnosed with endometrial cancer and should feature prominently in treatment and survivorship plans.


Gynecologic Oncology | 1990

Ovarian intraepithelial neoplasia demonstrated in patients with stage I ovarian carcinoma

Steven C. Plaxe; Liane Deligdisch; Peter Dottino; Carmel J. Cohen

Retrospective review of sections of ovary from 50 patients with stage I, grade 1-3, epithelial ovarian carcinoma was performed to assess presence of cellular and nuclear atypia in noncancerous tissue adjacent to the primary tumor; ovarian tissue from 50 patients undergoing incidental oophorectomy was reviewed as well. Atypia was more common in cancer patients, and finding the combination of nuclear atypia, defined as presence of pleomorphism or irregular chromatin distribution, with cellular atypia, defined as presence of stratification or loss of polarity, allowed separation of cancer and control groups with 98% sensitivity and 100% specificity. Presence of nuclear and cellular atypia was used to define ovarian intraepithelial neoplasia (OIN). If OIN is demonstrated to precede ovarian carcinoma, then it may offer insights into the development of ovarian cancer and may eventually increase the feasibility of screening for this disease.


American Journal of Obstetrics and Gynecology | 2008

Epidemiology of low-grade serous ovarian cancer

Steven C. Plaxe

OBJECTIVE The objective of the study was to determine whether the epidemiology of low-grade ovarian serous cancers is distinct from that of high-grade ovarian serous cancers. STUDY DESIGN The National Cancer Institutes Surveillance Epidemiology and End Results (SEER) program reports incidence, and survival, data from representative population based cancer registries. The SEER data are analyzed to compare the descriptive epidemiologies of low- and high-grade lesions. RESULTS Mean survival (99 vs 57 months) and age (55.5 vs 62.6 years) trends in annual incidence rate (-3.8% vs 1.4%), rate ratio of advanced to early disease (1.9 vs 10.2), rate ratio of post- to premenopausal incidence (5.0 vs 13.0). and difference in average age between advanced and early stage (none vs 2.5 years) are significantly different for patients with low-grade, compared with high-grade, disease. CONCLUSION Epidemiology of low-grade tumors appears sufficiently different from that of high-grade lesions to support the concept that low-grade ovarian serous cancers constitute a distinct clinical, and perhaps biologic, entity.


Cancer | 1982

Studies in prognostic factors relating to chemotherapy for advanced gastric cancer

Philip T. Lavin; Howard W. Bruckner; Steven C. Plaxe

The prognostic value of pretreatment information relating to prior treatment, demography, physical status, symptoms, disease involvement, pathologic, immunologic, and clinical chemistries were analyzed for a series of 322 patients with advanced gastric cancer. All patients received chemotherapy upon entry into Gastrointestinal Tumor Study Group protocols which were active between 1975 and 1978. Multivariate models were used to study relationships between prognostic factors and survival for all patients and objective tumor response for a subset of 137 patients with measurable disease. The initial performance status was a leading determinant of survival (P < 0.0001). In addition, new summary measures relating to blood chemistries (P < 0.01) and differential counts (P < 0.001) were shown to influence patient survival. Blood chemistry parameters included SGOT, total serum protein, and total direct bilirubin while differential counts included absolute granulocytes, lymphocytes, and monocytes. Thus, the initial performance status, measurable disease status, blood chemistries, and differential counts are recommended as stratification factors in the design and analysis of trials involving patients with advanced gastric cancer. The initial performance status was examined in relation to other pretreatment data. The performance status at study entry correlated independently with the degree of weight loss (P < 0.001), blood chemistries (P < 0.01), differential counts (P < 0.05), and peritoneal metastases (P < 0.05). The measurable and nonmeasurable subgroups were compared with respect to baseline characteristics. Patients with measurable disease had more liver metastases (56 versus 35%) and less peritoneal metastases (76 versus 49%) than patients with nonmeasurable disease. Controlling for the imbalance in liver and peritoneal metastases, the presence of measurable disease was less favorable than nonmeasurable disease with respect to survival. Regarding the pathways of disease spread, there was a strong correlation (P < 0.001) between primary tumor site within the stomach and location of metastases. Diffuse lesions were associated with the lowest frequency (25%) of liver metastases. Diffuse lesions (58%) and tumors of the pyloris (54%) were associated with the highest percentage of peritoneal metastases. Tumors of the cardia or fundus were more likely to metastasize to the liver while diffuse tumors were more likely to spread to the peritoneum. Pretreatment factors under study did not appear to be the dominant factors responsible for prolongation of survival in patients with an objective tumor response. Pretreatment factors predicted a three week advantage; however, a 22 week advantage was observed for responders over nonresponders.


Journal of Clinical Oncology | 1993

Phase I/pharmacokinetic study of high-dose progesterone and doxorubicin.

R D Christen; Edward F. McClay; Steven C. Plaxe; S S Yen; Sinil Kim; Saeeda Kirmani; L L Wilgus; Dennis D. Heath; D R Shalinsky; J L Freddo

PURPOSE We developed a new formulation of progesterone that permits administration of up to 10 g of progesterone as a continuous intravenous infusion over 24 hours and conducted a phase I clinical trial to determine whether progesterone could modulate the in vivo cytotoxicity of the P-glycoprotein substrate doxorubicin. PATIENTS AND METHODS Thirty-four patients with advanced malignancies were treated with increasing doses of progesterone and a fixed dose of 60 mg/m2 of doxorubicin given as an intravenous bolus 2 hours after starting a 24-hour intravenous infusion of progesterone. RESULTS Progesterone enhanced doxorubicin-induced myelotoxicity in a dose-dependent fashion without altering the pharmacokinetics of doxorubicin. The steady-state plasma concentration of progesterone at a dose level of 4 g was 4.1 +/- 0.9 mumol/L, which was higher than the minimal concentration required to reverse multidrug resistance (MDR) in vitro. CONCLUSION Progesterone enhanced the hematologic toxicity of doxorubicin without altering its pharmacokinetics, suggesting that progesterone could modulate P-glycoprotein at the level of pluripotent hematopoietic stem cells. Adequate tissue concentrations of progesterone could be achieved in vivo to modulate doxorubicin toxicity in the bone marrow and thus potentially in tumor tissue as well. Selectivity may potentially be gained by using hematopoietic growth factors to offset the enhanced hematologic toxicity of doxorubicin while leaving the enhancement of toxicity to tumor cells unchanged.


Investigational New Drugs | 1998

Phase I and pharmacokinetic study of intraperitoneal topotecan

Steven C. Plaxe; Randolph D. Christen; John O'Quigley; Patricia S. Braly; James L. Freddo; Edward F. McClay; Dennis D. Heath; Stephen B. Howell

Objective. To determine the maximum tolerated dose and pharmacokinetics of topotecan when administered by the intraperitoneal route. Methods. A dose-escalating Phase I trial was conducted in which fifteen % of the total dose was given as an intraperitoneal bolus in two litres of D5W and the remainder was given as a continuous intraperitoneal infusion over 24 hours. Treatments were given every 21 days. Pharmacokinetic analyses were performed at the recommended phase II dose. Results. Seventeen patients received a total of 43 cycles at 21-day intervals. The maximum tolerated dose was 4 mg/m2 and acute dose-limiting toxicity was neutropenia. Other toxicities included leukopenia, anemia, emesis, fever, and abdominal pain. Although no objective responses were achieved, five of ten patients with ascites had a decrease in fluid accumulation with administration of intraperitoneal topotecan. The recommended phase II dose is 3 mg/m2. Pharmacokinetic analysis performed at a dose of 3 mg/m2 demonstrated that elimination from the peritoneal cavity followed second-order kinetics with k1 = 1.6 hr-1, k2 = 0.3 hr-1 and first and second-phase half-lives of 0.49 and 2.7 hours, respectively. Plasma pharmacokinetic behavior was best described by first-order kinetics with k = 0.5 hr-1 and a half-life of 3.9 hours. The pharmacologic advantage, expressed as the peritoneal to plasma AUC ratio was 31.2. Conclusions. Intraperitoneal administration of topotecan at 3 mg/m2 results in a substantial increase in drug exposure for the peritoneal cavity without compromising systemic exposure; this may be beneficial for the treatment of patients with ovarian cancer or intraperitoneal carcinomatosis.


Gynecologic Oncology | 2014

Bariatric surgery decreases the risk of uterine malignancy.

Kristy K. Ward; Angelica M. Roncancio; Nina R. Shah; M.A. Davis; Cheryl C. Saenz; Michael T. McHale; Steven C. Plaxe

OBJECTIVE To describe the risk of uterine malignancy among women who have had weight loss surgery. METHODS We performed a retrospective cohort study among inpatient admissions of women 18years, or older, registered in the University HealthSystem Consortium (UHC) dataset. The rate of uterine malignancy per hospital admission was calculated. Rates were compared according to whether diagnoses at the time of discharge included history of bariatric surgery, and further, according to whether there was a diagnosis of obesity. RESULTS In admissions of patients who did not have a history of prior bariatric surgery, the rate of uterine malignancy was 599/100,000 (95% CI 590 to 610). Among obese women who had not previously undergone bariatric operations, the rate was 1409/100,000 (95% CI 1380 to 1440). Of women admitted who had a history of bariatric surgery, the rate of uterine malignancy was 408/100,000 (95% CI 370 to 450). The relative risk of uterine malignancy in all admissions for women who had prior bariatric surgery, compared to obese women who had not had bariatric surgery, was 0.29 (95% CI 0.26-0.32). Among women who had bariatric surgery and were not currently obese, the relative risk of uterine malignancy was 0.19 (95% CI 0.17-0.22) compared to obese women who had not undergone bariatric surgery. CONCLUSION A history of bariatric surgery is associated with a 71% reduced risk for uterine malignancy overall, and an 81% reduced risk if normal weight is maintained after surgery. This finding suggests that obesity may be a modifiable risk factor related to development of endometrial cancer.


Gynecologic Oncology | 2011

Changing demographics of cervical cancer in the United States (1973-2008).

Kristy K. Ward; Nina R. Shah; Cheryl C. Saenz; Michael T. McHale; Edwin A. Alvarez; Steven C. Plaxe

OBJECTIVE To describe changes in the cervical cancer population. METHODS The SEER database 9 registries from 1973 to 2008 were queried to perform a retrospective cohort study of women with invasive cervical cancer. Estimated annual percent change (EAPC) in incidence rates and 95% confidence intervals (CI) over the entire study period were compared according to age, stage, race, and cell type (squamous [SCC] and adenocarcinoma [ACA]). Proportions and odds ratios (OR) were calculated for patients diagnosed during the second half (1990-2008) compared to first half (1973-89) of the study period. RESULTS 40,363 women with cervical cancer were entered into SEER. The EAPC are falling fastest among those with localized disease (-2.5%; 95% CI -2.8 to -2.1), age≥50 (-3.0%; 95% CI=-3.2 to -2.8), and black women (-3.8%; 95% CI=-4.1 to -3.6). The odds of a newly diagnosed cervical cancer patient having advanced disease are 10% higher, being less than age 50 are 37% higher, and being Asian or Pacific Islander are 68% higher in the second time period as compared to the first. CONCLUSIONS In the US, the population with cervical cancer is changing. Patients are presently significantly more likely to be pre-menopausal, Asian or Pacific Islander, and more frequently have non-squamous histology than previously. These progressive and cumulative changes could be due to the disparate impact of current population based screening and prevention strategies. Understanding the implications of these evolving population characteristics may facilitate planning targeted studies and interventions for cervical cancer prevention, screening and treatment in the future.


American Journal of Obstetrics and Gynecology | 2013

The risk of uterine malignancy is linearly associated with body mass index in a cohort of US women

Kristy K. Ward; Angelica M. Roncancio; Nina R. Shah; M.A. Davis; Cheryl C. Saenz; Michael T. McHale; Steven C. Plaxe

OBJECTIVE We sought to quantify the relationship of uterine malignancy with body mass index (BMI). STUDY DESIGN The University HealthSystem Consortium database was queried to identify all women undergoing total hysterectomy with a recorded BMI in the overweight and obese categories. Least squares regression was applied to evaluate the association between increasing BMI and the proportion of women with a diagnosis of uterine malignancy. Multivariate binary logistic regression was performed to adjust for other known risk factors including age, race, and other comorbidities. RESULTS There were 6905 women who met inclusion criteria; 1891 (27.4%) of these had uterine malignancy. There is a linear relationship (y = 0.015x - 0.23, R(2) = 0.92) of the probability of uterine malignancy vs BMI. After adjusting for other risk factors, we found that each 1-U increase in BMI was significantly, independently associated with an 11% increase in the proportion of patients diagnosed with uterine malignancy (odds ratio, 1.11; 95% confidence interval, 1.09-1.13; P < .001). CONCLUSION In a population of women undergoing hysterectomy, we observed a linear increase in the frequency of uterine cancer associated with increasing BMI. This finding suggests that even relatively modest weight gain may significantly raise cancer risk. In the United States, the mean BMI for women is 26.5 kg/m(2) and it is estimated that more than half of US women have a BMI within the studys range. Our results could, therefore, be relevant to a majority of the population. The findings could increase popular acceptance of weight management as a key component of general health maintenance and, possibly, as an additional approach to cancer risk reduction.


International Journal of Radiation Oncology Biology Physics | 2015

Clinical Outcomes of Computed Tomography-Based Volumetric Brachytherapy Planning for Cervical Cancer

Daniel R. Simpson; Daniel J. Scanderbeg; Ruben Carmona; Riley M. McMurtrie; John Einck; Loren K. Mell; Michael T. McHale; Cheryl C. Saenz; Steven C. Plaxe; Terry A. Harrison; Arno J. Mundt; Catheryn M. Yashar

PURPOSE/OBJECTIVES A report of clinical outcomes of a computed tomography (CT)-based image guided brachytherapy (IGBT) technique for treatment of cervical cancer. METHODS AND MATERIALS Seventy-six women with International Federation of Gynecology and Obstetrics stage IB to IVA cervical carcinoma diagnosed between 2007 and 2014 were treated with definitive external beam radiation therapy (EBRT) with or without concurrent chemotherapy followed by high-dose-rate (HDR) IGBT. All patients underwent planning CT simulation at each implantation. A high-risk clinical target volume (HRCTV) encompassing any visible tumor and the entire cervix was contoured on the simulation CT. When available, magnetic resonance imaging (MRI) was performed at implantation to assist with tumor delineation. The prescription dose was prescribed to the HRCTV. RESULTS The median follow-up time was 17 months. Thirteen patients (17%) had an MRI done before brachytherapy, and 16 patients (21%) were treated without MRI guidance. The mean EBRT/IGBT sum 2-Gy equivalent dose (EQD2) delivered to the 90% volume of the HRCTV was 86.3 Gy. The mean maximum EQD2s delivered to 2 cm(3) of the rectum, sigmoid, and bladder were 67.5 Gy, 66.2 Gy, and 75.3 Gy, respectively. The 2-year cumulative incidences of local, locoregional, and distant failure were 5.8% (95% confidence interval [CI]: 1.4%-14.8%), 15.1% (95% CI: 5.4%-29.4%), and 24.3% (95% CI: 12.1%-38.9%), respectively. The 2-year overall and disease-free survival rates were 75% (95% CI, 61%-91%) and 73% (95% CI, 60%-90%), respectively. Twenty-nine patients (38%) experienced grade ≥ 2 acute toxicity, with 5 cases of acute grade 3 toxicity and no grade ≥ 4 toxicities. One patient experienced grade 3 gastrointestinal toxicity. No other late grade ≥ 3 events were observed. CONCLUSIONS This is the largest report to date of CT/MRI-based IGBT for the treatment of cervical cancer. The results are promising, with excellent local control and acceptable toxicity. Further investigation is needed to assess the long-term safety and efficacy of this treatment.

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Nina R. Shah

University of California

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L.M. Bean

University of California

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M.A. Davis

University of California

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Saeeda Kirmani

University of California

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