Cost benefit of intermittent pneumatic compression for venous thromboembolism prophylaxis in general surgery.

AIM: In moderate to high-risk general surgical patients, the cost effectiveness of mechanical prophylaxis for venous thromboembolism (VTE) is uncertain. Therefore, we determined the costs and savings of intermittent pneumatic compression (IPC) plus graduated compression stockings (GCS). METHODS: Postoperative VTE events in the absence of prophylaxis, efficacy of prophylaxis and costs of prophylaxis have been obtained from the English literature and Medicare 2004 reimbursement schedule. RESULTS: In 1000 moderate to high risk general surgical patients, in the absence of prophylaxis, the cost of investigating and treating 72 patients with clinical suspicion of DVT and 32 with PE is calculated to be $263,779. This corresponds to a cost of $263 per surgical patient. The cost of IPC combined with TED stockings in 1000 similar patients would be $66 760, and the cost of diagnosis and treatment of the reduced numbers (69% reduction) of clinical VTE is $ 83,574 making a total of $150 344. This means a saving of $133,435 ($263,779 - $150,344) per 1000 patients. This corresponds to a saving of $113 per surgical patient. Sensitivity analysis demonstrates that despite variation in costs or efficacy for IPC plus GCS, marked savings persist. CONCLUSIONS: Prophylaxis with IPC not only prevents VTE but also saves money.

Neonatal withdrawal syndrome following in utero exposure to paroxetine, clonazepam and olanzapine.

We describe a full-term infant with failed respiratory effort and decerebrate posturing following in utero exposure to paroxetine. All signs and symptoms associated with the paroxetine exposure were resolved by the second day of life. Upon discharge, the infant revealed a normal neurodevelopmental examination.

Defining practice patterns in gynecologic oncology to prevent pulmonary embolism and deep venous thrombosis.

OBJECTIVE: The goal of venous thromboembolism (VTE) prophylaxis is to reduce the morbidity and mortality associated with the development of a deep venous thrombosis (DVT) or pulmonary embolism (PE). Because women with gynecologic cancers are at high risk to develop VTE, we sought to determine the present practice patterns of gynecologic oncologists regarding their use of VTE prophylaxis. METHODS: 1073 members of the Society of Gynecologic Oncologists (SGO) were mailed surveys that asked about preferred methods to prevent the development of VTE after gynecologic oncology surgery. Data were collected by online member entry and return mail. Frequency distributions were calculated and nonparametric test used for comparisons. RESULTS: 343/1073 (34%) of SGO members and fellows responded. 142/343 (42%) preferred double prophylaxis consisting of external pneumatic compression (EPC) and an anticoagulant while 41% (n=141) preferred EPC with no additional anticoagulation. Of respondents choosing any anticoagulant, 40% preferred Enoxaparin pre- and/or postoperatively. Ovarian cancer patients were perceived by respondents to have the highest risk of developing a postoperative PE. CONCLUSIONS: Most respondents agree that women with gynecologic cancers undergoing major surgery should receive VTE prophylaxis, though there is not agreement as to which method is optimal. While 42% of members preferred double prophylaxis, 41% chose no additional measures other than EPC. Randomized studies in gynecologic oncology should be initiated in the United States to determine the optimal practice pattern.

Comparison of gracilis and rectus abdominis myocutaneous flap neovaginal reconstruction performed during radical pelvic surgery: flap-specific morbidity.

To compare flap-specific complications of gracilis myocutaneous (GM) and rectus abdominis myocutaneous (RAM) flap neovaginal reconstructions after radical pelvic surgery. The study was a single-institution retrospective review of patients undergoing concurrent radical pelvic surgery with GM or RAM neovaginal reconstructions performed on a gynecological oncology service, 1978-2003. Flap-specific complications were compared between the techniques. Forty-four GM and 32 RAM neovaginal reconstructions were analyzed: plastic surgeons developed 12 (27%) GM and 4 (13%) RAM flaps, with all other flaps performed by gynecological oncologists. Primary procedures included 54 (71%) total pelvic exenterations, with partial exenterations or radical vulvovaginectomies in 16 (21%) and 6 (8%) patients, respectively. Forty (53%) patients had received radiation and 28 (36%) received chemoradiation before radical surgery. There were no significant differences in patient characteristics, other than more frequent use of continent urinary conduits (P < 0.001) and a trend for more frequent sidewall radiation (P < 0.1) in the RAM group, reflecting use in more recent patients (P < 0.001). Median follow-up is 28 months (range: 2 weeks to 216 months), with 5% acute operative mortality. Flap-specific complications were significantly increased in GM patients (P < 0.03). Overall flap loss was significantly increased in GM patients (P < 0.02). Thirty (59%) of 51 patients surviving for more than 12 months reported coitus, with no significant difference between the groups. Because of lower overall incidence of flap-specific complications and significantly lower incidence of flap loss compared with GM flap, RAM flap has become our technique of choice for neovaginal reconstruction concurrent with radical pelvic surgery.

High-risk gestational trophoblastic neoplasia with brain metastases: individualized multidisciplinary therapy in the management of four patients.

PURPOSE: To report our recent experience managing four patients with brain metastases of gestational trophoblastic neoplasia (GTN), coordinating systemic chemotherapy with early neurosurgical intervention or stereotactic radiosurgery and intensive supportive care during initial therapy to prevent early mortality. MATERIALS AND METHODS: A series of four consecutive patients with brain metastases from high-risk Stage IV GTN managed at our institution in 2003 and 2005. Patients were assigned FIGO stage and risk score prospectively. Because of concern for chronic toxicity resulting from concurrent moderate dose methotrexate and whole brain radiation, an individualized multidisciplinary approach was used to manage patients. RESULTS: All four women presented with brain and pulmonary metastases; one had multiple liver metastases. Neurological symptoms at presentation included grand mal seizures in 2 patients, left upper extremity hemiparesis and headache each in 1 patient, while 1 patient was asymptomatic. Index pregnancies were term pregnancies in all patients with interval from prior delivery ranging from 2 weeks to 4 years. Two had received prior chemotherapy for postmolar GTN prior to the index pregnancy with incomplete follow-up. Initial hCG values ranged from 26,400 to 137,751 mIU/ml; FIGO risk scores were > or =16 for all patients. Systemic combination chemotherapy was initiated with etoposide and cisplatin followed by moderate/high-dose (500-1000 mg/m(2)) methotrexate combinations. Craniotomy was used before or during the first chemotherapy cycle to extirpate solitary lesions in 3 patients, while stereotactic radiosurgery was administered after the first cycle to treat two brain lesions in the remaining patient. None received whole brain radiation or intrathecal methotrexate. In one patient, selective angiographic embolization was used to control hemorrhage from multiple liver metastases. Two patients required ventilator support early in treatment to allow stabilization from intrathoracic hemorrhage and neutropenic sepsis with respiratory distress syndrome, respectively. Hysterectomy was performed in one patient after completion of salvage chemotherapy. All have completed maintenance chemotherapy and are in prolonged remission (12-24 months). Neurologic sequelae include persistent left upper extremity dyskinesia and weakness in one patient, and episodic grand mal seizures and pseudoseizures in a second patient with a pre-existing seizure disorder. CONCLUSION: This case series documents the utility for a multidisciplinary approach to the treatment of brain metastases from GTN. Using early craniotomy or stereotactic radiosurgery combined with etoposide-cisplatin and moderate/high-dose methotrexate combination chemotherapy, we were able to stabilize patients early in their treatment and avoid whole brain radiation therapy or intrathecal chemotherapy.

Phase I/II trial of intravenous Doxil and whole abdomen hyperthermia in patients with refractory ovarian cancer.

OBJECTIVE: A phase I/II study of Doxil combined with whole abdomen hyperthermia was conducted in patients with refractory ovarian cancer. Liposomal doxorubicin combined with hyperthermia has been shown to increase both liposomal delivery and drug extravasation into tumour xenografts resulting in enhanced cytotoxic effects. PATIENTS AND METHODS: Thirty patients with either recurrent or persistent epithelial ovarian cancer were enrolled. All patients had either measurable or assessable disease. Patients received intravenous (IV) Doxil at a dose of 40 mg m-2 as a 1-h infusion followed by whole abdomen hyperthermia. The phase I portion of the study was performed to determine the maximal tolerated dose (MTD) of hyperthermia. Quality of life (QoL) was performed at baseline, prior to each cycle and every 3 months. Plasma pharmacokinetic studies were performed with the first cycle. RESULTS: Ten patients participated in the phase I portion of the study which demonstrated that the MTD of hyperthermia was 60 min after either average vaginal and rectal temperatures of 40 degrees C had been achieved or after 30 min of power application, whichever was shorter. All 30 patients were either paclitaxel and/or platinum resistant initially or developed resistant disease. The median number of prior chemotherapeutic regimens was three (range 2-8) and six patients had been previously treated with Doxil. There were three partial responses for a response rate of 10% (95% CI: [2%, 27%]) and eight patients (27%; 95% CI: [12%, 46%]) had disease stabilization. The median time to progression or death was 3.4 months (95% CI: [2.6, 5.2]) and the median survival was 10.8 months (95% CI: [8.8, 17.4]). Twelve patients (40%) experienced palmar-plantar erythrodysesthesia (PPE), but only four (13%) experienced grade 3-4 PPE toxicity. Doxil systemic exposure was higher in those with grade 3-4 PPE compared to those with no PPE. None of the patients had grade 3-4 thermal toxicity due to hyperthermia. QoL was not decreased in patients responding to therapy. CONCLUSIONS: Therapy with intravenous Doxil and whole abdomen hyperthermia for patients with platinum/paclitaxel resistant ovarian cancer is feasible and does not negatively impact quality of life.

Rectus abdominis myocutaneous flaps for neovaginal reconstruction after radical pelvic surgery.

The objective of this article is to compare the flap-specific complications associated with vertical (VRAM) and transverse (TRAM) rectus abdominis myocutaneous flap vaginal reconstructions performed during radical pelvic procedures. A retrospective chart review was performed to identify all patients who underwent VRAM and TRAM neovaginal reconstructions performed on the Gynecologic Oncology Service at Duke University Medical Center. Flap-specific complications were compared between the two techniques. From 1988 to 2003, 14 VRAM and 18 TRAM flap neovaginal reconstructions were performed on 32 women during the course of 22 (68%) total pelvic exenterations, 8 (25%) partial exenterations, and 2 (6%) radical vulvovaginectomies. Twenty-eight (88%) patients had been previously treated with radiation therapy or concurrent chemoradiation. Associated procedures included continent urinary conduit in 21 (66%), rectosigmoid reanastomosis in 8 (25%), and intraoperative or postoperative sidewall radiation therapy in 7 (22%) of patients. Overall median survival was 14 months (range: 2-week postoperative death to 65 months), with two (6%) acute postoperative mortalities. Fifteen flap-specific complications occurred in 12 (38%) patients, with no significant differences in flap type. Abdominal wound complications included four (12%) superficial wound separations, while one (3%) patient had a fascial dehiscence associated with complex fistulas that contributed to her death, but no patient developed incisional hernia. One patient each developed > 50% flap loss after TRAM and < 50% flap loss after VRAM flap, respectively. Four (12%) patients developed vaginal stricture or stenosis, two (6%) required percutaneous drainage of pelvic abscess or hematoma, and two (6%) developed rectovaginal fistula. Univariate analysis revealed a trend for increasing flap loss with body mass index > 35 (P = 0.056, Fisher exact two-tailed test), but there were no significant associations with other patient characteristics or flap-specific complications. Thirteen (62%) of 21 patients who survived >12 months reported coitus. Both VRAM and TRAM are reliable techniques for neovaginal reconstructions after radical pelvic surgery and have a similar distribution of flap-specific complications involving the donor and recipient sites.

Cost-effectiveness of combination thromboembolism prophylaxis in gynecologic oncology surgery.

OBJECTIVE: To compare the cost-effectiveness of external pneumatic compression devices with and without the addition of low-molecular-weight heparin for the prevention of deep vein thrombosis in high-risk surgical patients with gynecologic cancer. METHODS: A Markov decision analytic model was used to estimate the costs and outcomes associated with the prophylactic use of external pneumatic compression with and without low-molecular-weight heparin in patients undergoing gynecologic surgery. We estimated cost per fatal pulmonary embolus prevented, cost per deep vein thrombus prevented, and cost per life-year saved. Probability estimates for various outcomes and efficacies were obtained from the literature, using data specific for gynecologic surgery patients when available. RESULTS: In the base case scenario, cost-effectiveness estimates for combination prophylaxis varied from 10,091 dollars per life-year saved for a 35-year-old patient with IB cervix cancer patient to 50,181 dollars for a 65-year-old patient with stage IIIC ovarian cancer, costs within the 50,000-65,000 dollars per life-year saved threshold considered to be cost-effective. Combination prophylaxis appeared to be cost-effective in gynecologic oncology patients as long as the risk of perioperative thromboembolism using this method of prevention was less than or equal to 4%. Sensitivity analysis indicated that variation of the marginal cost of low-molecular-weight heparin and the marginal effectiveness to extremes did not change the conclusions of the statistical model. CONCLUSION: The use of combination therapy external pneumatic compression is estimated to be cost-effective for high-risk gynecologic oncology patients undergoing surgery. Clinical trials to determine the efficacy of perioperative combination therapy in gynecologic surgery are justified.

Oral topotecan as single-agent second-line chemotherapy in patients with advanced ovarian cancer.

PURPOSE: To evaluate oral topotecan as single-agent, second-line therapy in patients with ovarian cancer previously treated with a platinum-based regimen. PATIENTS AND METHODS: Patients (N = 116) received oral topotecan 2.3 mg/m2 daily for 5 days every 21 days. Eligibility criteria included histologic diagnosis of International Federation of Gynecology and Obstetrics stage III or IV epithelial ovarian cancer, bidimensionally measurable disease, prior platinum-containing chemotherapy, age > or = 18 years, performance status < or = 2, and life expectancy > or = 12 weeks. RESULTS: Overall response rate was 21.6% (25 of 116 patients). Median duration of response was 25.0 weeks; median time to response was 8.4 weeks. Median time to progression was 14.1 weeks; median survival was 62.2 weeks. Grade 4 neutropenia was experienced by 50.4% of patients in 13.4% of courses administered. Grade 4 thrombocytopenia was experienced by 22.1% of patients in 5.1% of courses. Grade 3 or 4 anemia was experienced by 29.2% of patients in 8.5% of courses. Most frequent nonhematologic toxicities were predominantly (> 90%) grade 1 or 2 and included nausea, alopecia, diarrhea, and vomiting. CONCLUSION: Second-line oral topotecan administered at 2.3 mg/m2 for 5 days every 21 days demonstrated activity in patients with progressive or recurrent ovarian cancer after first-line platinum-based chemotherapy. This activity was comparable to that seen in previous studies with intravenous topotecan. Grade 4 neutropenia was less frequent with oral topotecan than previously reported for intravenous topotecan. Oral topotecan is an active, tolerable, and convenient formulation of an established agent for the second-line treatment of advanced epithelial ovarian cancer and may also facilitate exploring prolonged treatment schedules.

Resistance to xenobiotic-induced autoimmunity maps to chromosome 1.

Although evidence indicates that environmental factors play a major role in precipitating systemic autoimmunity in genetically susceptible individuals, little is known about the mechanisms involved. Certain heavy metals, such as mercury, are potent environmental immunostimulants that produce a number of immunopathologic sequelae, including lymphoproliferation, hypergammaglobulinemia, and overt systemic autoimmunity. Predisposition to such metal-induced immunopathology has been shown to be influenced by both MHC and non-MHC genes, as well as susceptibility to spontaneous lupus, in mice and other experimental animals. Among the various mouse strains examined to date, the DBA/2 appears to uniquely lack susceptibility to mercury-induced autoimmunity (HgIA), despite expressing a susceptible H-2 haplotype (H-2d). To define the genetic basis for this trait, two genome-wide scans were conducted using F2 intercrosses of the DBA/2 strain with either the SJL or NZB strains, both of which are highly susceptible to HgIA. A single major quantitative trait locus on chromosome 1, designated Hmr1, was shown to be common to both crosses and encompassed a region containing several lupus susceptibility loci. Hmr1 was linked to glomerular immune complex deposits and not autoantibody production, suggesting that DBA/2 resistance to HgIA may primarily involve the later stages of disease pathogenesis. Identification and characterization of susceptibility/resistance genes and mechanisms relevant to the immunopathogenesis of mercury-induced autoimmunity should provide important insights into the pathogenesis of autoimmunity and may reveal novel targets for intervention.

Neonatal pulmonary hypertension--urea-cycle intermediates, nitric oxide production, and carbamoyl-phosphate synthetase function.

BACKGROUND: Endogenous production of nitric oxide is vital for the decrease in pulmonary vascular resistance that normally occurs after birth. The precursor of nitric oxide is arginine, a urea-cycle intermediate. We hypothesized that low concentrations of arginine would correlate with the presence of persistent pulmonary hypertension in newborns and that the supply of this precursor would be affected by a functional polymorphism (the substitution of asparagine for threonine at position 1405 [T1405N]) in carbamoyl-phosphate synthetase, which controls the rate-limiting step of the urea cycle. METHODS: Plasma concentrations of amino acids and genotypes of the carbamoyl-phosphate synthetase variants were determined in 65 near-term neonates with respiratory distress. Plasma nitric oxide metabolites were measured in a subgroup of 10 patients. The results in infants with pulmonary hypertension, as assessed by echocardiography, were compared with those in infants without pulmonary hypertension. The frequencies of the carbamoyl-phosphate synthetase genotypes in the study population were assessed for Hardy-Weinberg equilibrium. RESULTS: As compared with infants without pulmonary hypertension, infants with pulmonary hypertension had lower mean (+/-SD) plasma concentrations of arginine (20.2+/-8.8 vs. 39.8+/-17.0 micromol per liter, P<0.001) and nitric oxide metabolites (18.8+/-12.7 vs. 47.2+/-11.2 micromol per liter, P=0.05). As compared with the general population, the infants in the study had a significantly skewed distribution of the genotypes for the carbamoyl-phosphate synthetase variants at position 1405 (P<0.005). None of the infants with pulmonary hypertension were homozygous for the T1405N polymorphism. CONCLUSIONS: Infants with persistent pulmonary hypertension have low plasma concentrations of arginine and nitric oxide metabolites. The simultaneous presence of diminished concentrations of precursors and breakdown products suggests that inadequate production of nitric oxide is involved in the pathogenesis of neonatal pulmonary hypertension. Our preliminary observations suggest that the genetically predetermined capacity of the urea cycle--in particular, the efficiency of carbamoyl-phosphate synthetase--may contribute to the availability of precursors for nitric oxide synthesis.

Phase III trial of standard-dose intravenous cisplatin plus paclitaxel versus moderately high-dose carboplatin followed by intravenous paclitaxel and intraperitoneal cisplatin in small-volume stage III ovarian carcinoma: an intergroup study of the Gynecologic Oncology Group, Southwestern Oncology Group, and Eastern Cooperative Oncology Group.

PURPOSE: To compare the progression-free and overall survival in small-volume residual ovarian cancer after treatment with intravenous (IV) cisplatin and paclitaxel or an experimental regimen of IV carboplatin followed by IV paclitaxel and intraperitoneal cisplatin. PATIENTS AND METHODS: Patients were randomized to receive either IV paclitaxel 135 mg/m(2) over 24 hours followed by IV cisplatin 75 mg/m(2) every 3 weeks for six courses or IV carboplatin (area under curve 9) every 28 days for two courses, then IV paclitaxel 135 mg/m(2) over 24 hours followed by intraperitoneal (IP) cisplatin 100 mg/m(2) every 3 weeks for six courses. RESULTS: Of the 523 patients who entered this trial, 462 were determined to be assessable, with prognostic factors well balanced between the treatments. Neutropenia, thrombocytopenia, and gastrointestinal and metabolic toxicities were greater in the experimental arm. As a result, 18% of the patients received < or = two courses of IP therapy. Progression-free survival was superior for patients randomized to the experimental treatment arm (median, 28 v 22 months; relative risk, 0.78; log-rank P =.01, one-tail). There was a borderline improvement in overall survival associated with this regimen (median, 63 v 52 months; relative risk, 0.81; P =.05, one-tail). CONCLUSION: An experimental regimen including moderately high-dose IV carboplatin followed by IP paclitaxel and IV cisplatin yielded a significant improvement in progression-free survival when compared with a standard regimen of IV cisplatin and paclitaxel. Because the improvement in overall survival was of borderline statistical significance and toxicity was greater, the experimental arm is not recommended for routine use. However, the results provide direction for further clinical investigation in small-volume ovarian cancer.

Xenobiotic acceleration of idiopathic systemic autoimmunity in lupus-prone bxsb mice.

The diverse genetic backgrounds of lupus-prone murine models, which produce both quantitative and qualitative differences in disease expression, may be a valuable resource for studying the influence of environmental exposure on autoimmune disease in sensitive populations. We tested this premise by exposing autoimmune-prone BXSB and the nonautoimmune C57BL/6 mice to the heavy metal mercury. Although both strains express a nonsusceptible H-2 haplotype, exposure to mercury accelerated systemic autoimmunity in both male and female BXSB mice, whereas the C57BL/6 mice were resistant. The subclasses of antichromatin antibodies elicited in BXSB mice by mercury exposure were more consistent with the predominant Th1-type response of idiopathic disease than with the Th2-type response found in mercury-induced autoimmunity (HgIA). The appearance and magnitude of both humoral and cellular features of systemic autoimmunity correlated with the mercury dose. Furthermore, environmentally relevant tissue levels of mercury were associated with exacerbated systemic autoimmunity. These studies demonstrate that xenobiotic exposure can accelerate spontaneous systemic autoimmunity, and they support the possibility that low-level xenobiotic exposure enhances susceptibility to systemic autoimmunity in genetically susceptible individuals.

Pneumatic compression versus low molecular weight heparin in gynecologic oncology surgery: a randomized trial.

OBJECTIVE: To compare the efficacy and treatment-related complications of low molecular weight heparin and external pneumatic compression in the prevention of venous thromboembolism of postoperative gynecologic oncology patients. METHODS: A total of 211 patients over age 40 years, undergoing a major operative procedure for gynecologic malignancy, were randomized to receive perioperative thromboembolism prophylaxis with either low molecular weight heparin (n = 105) or external pneumatic compression (n = 106). Demographic data and clinical outcome were recorded for each patient. All patients underwent bilateral Doppler ultrasound of the lower extremities on postoperative days 3-5 to evaluate for the presence of occult deep vein thrombosis. A follow-up interview 30 days after surgery sought to detect patients who developed deep vein thrombosis or pulmonary embolism after hospital discharge. RESULTS: Venous thrombosis was diagnosed in two patients receiving low molecular weight heparin and in one patient receiving external pneumatic compression. The frequency of bleeding complications, measured by the number of required perioperative transfusions, and estimated intraoperative blood loss was similar between the two groups. CONCLUSION: Low molecular weight heparin and external pneumatic compression are similarly effective in the postoperative prophylaxis of thromboembolism. The use of low molecular weight heparin is not associated with an increased risk of bleeding complications when compared with external pneumatic compression. We believe that both modalities are reasonable choices for prophylaxis in this high-risk group of patients.

Protein N-arginine methylation in subcellular fractions of lymphoblastoid cells.

Arginine methylation in RNA-binding proteins containing arginine- and glycine-rich RGG motifs is catalyzed by specific protein arginine N-methyltransferase in cells. We previously showed that lymphoblastoid cells grown in the presence of an indirect methyltransferase inhibitor, adenosine dialdehyde (AdOx), accumulated high level of hypomethylated protein substrates for the endogenous protein methyltransferases or recombinant yeast arginine methyltransferase [Li, C. et al. (1998) Arch. Biochem. Biophys. 351, 53-59]. In this study we fractionated the lymphoblastoid cells to locate the methyltransferases and the substrates in cells. Different sets of hypomethylated methyl-accepting polypeptides with wide range of molecular masses were present in cytosolic, ribosomal, and nucleus fractions. The methylated amino acid residues of the methyl-accepting proteins in these fractions were determined. In all three fractions, dimethylarginine was the most abundant methylated amino acid. The protein-arginine methyltransferase activities in the three fractions were analyzed using recombinant fibrillarin (a nucleolar RGG protein) as the methyl-accepting substrate. Fibrillarin methylation was strongest in the presence of the cytosolic fraction, followed by the ribosomal and then the nucleus fractions. The results demonstrated that protein-arginine methyltransferases as well as their methyl-accepting substrates were widely distributed in different subcellular fractions of lymphoblastoid cells.

Proteolytic cleavage of a self-antigen following xenobiotic-induced cell death produces a fragment with novel immunogenic properties.

The heavy metal mercury elicits a genetically restricted autoantibody response in mice that targets the nucleolar autoantigen fibrillarin. HgCl2-induced cell death of macrophages resulted in the proteolytic cleavage of fibrillarin. A prominent feature of mercury-induced cell death was the generation of a 19-kDa fragment of fibrillarin that was not found following apoptotic or nonapoptotic cell death induced by stimuli other than mercury. Proteolysis of fibrillarin lacking cysteines, and therefore unable to bind mercury, also produced the 19-kDa fragment, suggesting that a mercury-fibrillarin interaction was not necessary for the unique cleavage pattern of this self-Ag. In contrast to immunization with full-length fibrillarin, the 19-kDa fragment produced anti-fibrillarin Abs with some of the properties of the HgCl2-induced anti-fibrillarin response. We propose that cell death following exposure to an autoimmunity-inducing xenobiotic can lead to the generation of novel protein fragments that may serve as sources of antigenic determinants for self-reactive T lymphocytes.

The outcome of stage I-II clinically and surgically staged papillary serous and clear cell endometrial cancers when compared with endometrioid carcinoma.

PURPOSE: The aim of this study was to compare survival and recurrence in clinical and surgical stage I-II papillary serous (PS), clear cell (CC), and endometrioid (EM) cancers of the endometrium and examine the prognostic utility of myometrial invasion. METHODS: Clinical, surgicopathologic, and survival data were retrospectively collected on 574 clinical stage I-II endometrial cancer patients, including 53 PS and 18 CC (based on postoperative histology), undergoing hysterectomy at Duke University Medical Center between 1967 and 1990. All staging material was available and reexamined prior to this analysis, and FIGO surgical staging was retrospectively assigned. Prognostic variables examined included age, stage, grade, myometrial invasion, lymph-vascular space invasion (LVSI), and histology. PS and CC histologic subtypes were compared as both common category and discrete categories versus EM, EM grade 1 (EM1), EM grade 2 (EM2), and EM grade 3 (EM3). Statistical analyses were performed using chi(2), Fisher's exact, and Wilcoxon rank sum tests, Cox regression analysis, and Kaplan-Meier survival analysis. RESULTS: PS tumors accounted for 9%, CC for 3%, and EM for 88% of cases. Recurrences were more frequent among PS (38%) and CC (22%) compared with EM (9%) (P < 0.001 and 0.08, respectively), and PS recurred more frequently than EM3 alone (20%) (P = 0.06). Among PS, CC, and EM3 patients with recurrences there were no statistical differences in the proportion that received preoperative or postoperative radiotherapy or chemotherapy. Prognostic factors for shorter survival included age >=60, surgical stage III+IV, presence of LVSI, histology (PS, CC, or EM3), and >=50% myometrial invasion. The estimated 5-year survival of PS+CC patients with <2 mm myometrial invasion is 0.56 compared to 0.93 for EM patients (P < 0. 001). PS + CC tumors confined to the endometrium had a 5-year survival of 0.60 compared to 0.98 and 1.00 for EM and EM3, respectively. The 5-year survival for surgically staged IA patients (0.57) was not different from stages IB and IC combined (0.53) (P = 0.72). The 5-year survival for surgical stage I + II PS + CC patients (0.56) was comparable to that for clinical stage I + II PS + CC patients (0.46) and remained significantly smaller than that for EM patients (0.86) (P < 0.001). CONCLUSION: Recurrences are more frequent among PS and CC tumors compared with EM and among PS compared with EM3. When controlled for surgical stage I-II tumors, 5-year survival for PS + CC patients remains comparable to that of clinical stage I-II patients and below that of EM. Prognostic factors for survival in PS and CC patients include age, stage, and LVSI. PS, CC, and EM3 subtypes together are predictors of poor survival. Thorough extended surgical staging is indicated in PS and CC tumors, and prospective trials of aggressive adjuvant therapies for surgical stage I-II tumors are needed to improve outcome in PS and CC patients.

Cost-effectiveness of deep venous thrombosis prophylaxis in gynecologic oncology surgery.

OBJECTIVE: To estimate the cost-effectiveness of preventive strategies for deep vein thrombosis (DVT) in patients undergoing surgery for gynecologic cancer. METHODS: A model was constructed to estimate the costs and outcomes associated with the use of external pneumatic compression, unfractionated heparin, and low molecular weight heparin in women with cervical, endometrial, and ovarian cancer. We estimated cost per DVT prevented, per fatal pulmonary embolus (PE) prevented, and per life-year saved. Probability estimates for various outcomes and efficacies were obtained from the literature, using data specific for gynecologic patients when available. RESULTS: Cost-effectiveness estimates ranged from $27 per life-year saved for a 55-year-old endometrial cancer patient to $5132 per life-year saved for a 65-year-old with ovarian cancer. Although low molecular weight heparin and unfractionated heparin were cost-effective compared with no prophylaxis, each was less effective than external pneumatic compression in the base case. The results of the analysis were sensitive to assumptions about the relative risk of DVT, the life expectancy of the patient, the costs of future treatment, and the relative effectiveness of the different strategies: If unfractionated heparin or low molecular weight heparin is at least 2-3% more effective than external pneumatic compression, then the incremental cost per life-year of either would be less than $50,000 compared with external pneumatic compression. CONCLUSION: Prophylaxis of DVT is cost-effective in terms of life-years gained even for patients with relatively short life expectancies, such as ovarian cancer patients. External pneumatic compression appears to be the most cost-effective strategy under our baseline assumptions, but further studies in gynecologic cancer are needed to validate our conclusions.

Lupus-prone mice as models to study xenobiotic-induced acceleration of systemic autoimmunity.

The linkage between xenobiotic exposures and autoimmune diseases remains to be clearly defined. However, recent studies have raised the possibility that both genetic and environmental factors act synergistically at several stages or checkpoints to influence disease pathogenesis in susceptible populations. These observations predict that individuals susceptible to spontaneous autoimmunity should be more susceptible following xenobiotic exposure by virtue of the presence of predisposing background genes. To test this possibility, mouse strains with differing genetic susceptibility to murine lupus were examined for acceleration of autoimmune features characteristic of spontaneous systemic autoimmune disease following exposure to the immunostimulatory metals nickel and mercury. Although NiCl(2) exposure did not exacerbate autoimmunity, HgCl(2) significantly accelerated systemic disease in a strain-dependent manner. Mercury-exposed (NZB X NZW)F1 mice had accelerated lymphoid hyperplasia, hypergammaglobulinemia, autoantibodies, and immune complex deposits. Mercury also exacerbated immunopathologic manifestations in MRL+/+ and MR -lpr mice. However, there was less disease acceleration in lpr mice compared with MRL+/+ mice, likely due to the fact that environmental factors are less critical for disease induction when there is strong genetic susceptibility. Non-major histocompatibility complex genes also contributed to mercury-exacerbated disease, as the nonautoimmune AKR mice, which are H-2 identical with the MRL, showed less immunopathology than either the MRL/lpr or MRL+/+ strains. This study demonstrates that genetic susceptibility to spontaneous systemic autoimmunity can be a predisposing factor for HgCl(2)-induced exacerbation of autoimmunity. Such genetic predisposition may have to be considered when assessing the immunotoxicity of xenobiotics. Additional comparative studies using autoimmune-prone and nonautoimmune mice strains with different genetic backgrounds will help determine the contribution that xenobiotic exposure makes in rendering sensitive populations susceptible to autoimmune diseases.