991 resultados para SKIN ALLOGRAFT SURVIVAL


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We have cloned and characterized for the first time an allograft inflammatory factor 1 (Sn-AIF-1) from the Antarctic sea urchin. We report the cloning of Sn-AIF-1 cDNA and the characterization of its expression in coelomocytes after a bacterial challenge. The cDNA Sn-AIF-1 has a size of 608 bp and encodes a polypeptide of 151 aa. The deduced amino acid sequence has a putative size of 17.430 Da, an isoelectric point of 4.92, and shows 2 elongation factor handlike motifs that normally bind calcium ions. BLAST analysis revealed close matches with other known AIF-1. The deduced amino acid sequence of Sn-AIF-1 showed high homology with AIF-1 in vertebrates such as fish, mice, and humans; and in the case of invertebrates, the major degree of identity (55%) was with a predicted sequence of the purple sea urchin AIF-1, and 52% corresponded to a sponge. Expression of Sn-AIF-1 mRNA was analyzed by qPCR. Sn-AIF-1 mRNA expression was measured from coelomocytes after a bacterial challenge using RT-PCR and revealed that the gene was upregulated after 24 h. Sn-AIF-1 could participate in the inflammatory response, particularly in the activation of coelomocytes and their survival.

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Human leukocyte antigen-G (FILA-G) plays a well-recognized role in the modulation of the immune response, and HLA-G expression has been associated with increased graft survival and decreased rejection episodes. To investigate the role of the HLA-G 3' untranslated region (3'UTR) in renal transplantation, we evaluated several polymorphic sites (14-bp Del/Ins +3003T/C, +3010C/G, +3027C/A, +3035C/T, +3142G/C, and +3187A/G) in patients exhibiting or not exhibiting rejection episodes. A total of 104 patients (15 with acute and 48 with chronic rejection, and 41 with no rejection) and 142 healthy individuals were studied. HLA-G 3'UTR was typed by direct sequencing. The +3035C-C genotype was more frequent in patients exhibiting chronic rejection compared with healthy controls, and the +3035C-T genotype was less frequent in chronic rejection compared with patients without rejection (acute plus chronic) or compared with healthy controls. The +3187G-A genotype, in which the A allele is associated with increased mRNA degradation, showed increased frequency in the rejection group (acute plus chronic) when compared with healthy controls. The 14 base pair Deletion/Insertion genotype was marginally increased in patients with acute rejection. This is the first study to show associations among numerous polymorphic sites in the HLA-G 3'UTR in kidney allotransplantation, which may contribute to the understanding of HLA-G post-transcriptional mechanisms. (C) 2012 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

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Abstract Background Squamous cell carcinoma (SCC) of the skin of the trunk and extremities may present lymph node metastasis with difficult disease control and poor survival. The purpose of this study was to identify risk factors for lymph node metastasis and outcome. Patients/Methods Retrospective review of 57 patients with locally advanced SCC of the trunk and extremities was performed and several clinical variables including age, gender, ethnicity, previously injured skin (burns, scars, ulcers and others), patient origin (rural or urban), anatomic site and treatment were studied. Results Fifteen patients presented with previous skin lesions. Thirty-six were classified as T3 tumors and 21 as T4; 46 were N0, and 11, N1. Eleven N0 patients presented lymph node metastasis during follow up. Univariate analysis identified previous skin lesions (ulcers and scars) as risk factor for lymph node metastasis (p = 0.047). Better survival was demonstrated for T3 (p = 0.018) classification. N0 patients who presented lymph node metastasis during follow up (submitted to lymphadenectomy) had similar survival to patients without lymph node recurrence (p = 0.219). Conclusion Local advanced tumors are at risk of lymph node metastasis. Increased risk is associated to previous lesions at tumor site. T4 classification have worse prognosis. Lymph node recurrences in N0 patients, once treated, did not affect survival. For these patients, we propose close follow up and prompt treatment of lymph node metastasis. These results do not support indication for elective lymphadenectomy or sentinel node mapping. Further prospective studies must address this issue.

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Pancreatic islet transplantation represents a fascinating procedure that, at the moment, can be considered as alternative to standard insulin treatment or pancreas transplantation only for selected categories of patients with type 1 diabetes mellitus. Among the factors responsible for leading to poor islet engraftment, hypoxia plays an important role. Mesenchymal stem cells (MSCs) were recently used in animal models of islet transplantation not only to reduce allograft rejection, but also to promote revascularization. Currently adipose tissue represents a novel and good source of MSCs. Moreover, the capability of adipose-derived stem cells (ASCs) to improve islet graft revascularization was recently reported after hybrid transplantation in mice. Within this context, we have previously shown that hyaluronan esters of butyric and retinoic acids can significantly enhance the rescuing potential of human MSCs. Here we evaluated whether ex vivo preconditioning of human ASCs (hASCs) with a mixture of hyaluronic (HA), butyric (BU), and retinoic (RA) acids may result in optimization of graft revascularization after islet/stem cell intrahepatic cotransplantation in syngeneic diabetic rats. We demonstrated that hASCs exposed to the mixture of molecules are able to increase the secretion of vascular endothelial growth factor (VEGF), as well as the transcription of angiogenic genes, including VEGF, KDR (kinase insert domain receptor), and hepatocyte growth factor (HGF). Rats transplanted with islets cocultured with preconditioned hASCs exhibited a better glycemic control than rats transplanted with an equal volume of islets and control hASCs. Cotransplantation with preconditioned hASCs was also associated with enhanced islet revascularization in vivo, as highlighted by graft morphological analysis. The observed increase in islet graft revascularization and function suggests that our method of stem cell preconditioning may represent a novel strategy to remarkably improve the efficacy of islets-hMSCs cotransplantation.

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Non-melanoma skin cancers (NMSCs) are the most common malignancies after solid organ transplantation. Their incidence increases with time after transplantation. Calcineurin-inhibitors (CNIs) and azathioprine are known as skin neoplasia-initiating and -enhancing immunosuppressants. In contrast, increasing clinical experience suggests a relevant antiproliferative effect of mammalian target of rapamycin inhibitors, also named proliferation signal inhibitors (PSIs). We report the case of a cardiac allograft recipient with an impressive and consolidated reduction of recurrent NMSC, observed after conversion from CNI-therapy to a PSI-based protocol.

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Survivin is a member of the inhibitor of apoptosis (IAP) protein family acting at the intersection between proliferation and cell survival. This protein exhibits low or undetectable expression in most adult tissues but is increased in the majority of cancers. Suggested to be one of the most cancer-specific proteins identified to date, survivin acts as a signalling node in tumour maintenance and, after first promising results, is now attracting increasing attention as a target in anti-cancer therapy. In the skin, survivin has been implicated in a number of pathological conditions such as psoriasis and tumours of melanocytic and epithelial origin. Its expression can correlate with tumour severity, metastasis and decreased patient survival and has been inversely correlated with the sensitivity to cytotoxic agents used in anti-cancer therapy. Survivin may also be of importance for normal epidermal homeostasis possibly supporting self-renewal of epidermal stem cells. In this review, the authors summarize and discuss current data of survivin in skin biology and provide a comprehensive compilation of survivin expression in skin pathologies with focus on future therapeutical use.

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AIM: To study prospectively patients after heart transplantation with respect to quality of life, mortality, morbidity, and clinical parameters before and up to 10 years after the operation. METHODS: Sixty patients (47.9 +/- 10.9 years, 57 men, 3 women) were transplanted at the University of Vienna Hospital, Department for Heart and Thorax Surgery and were included in this study. They were assessed when set on the waiting list, then exactly one, 5 and 10 years after the transplantation. The variables evaluated included physical and emotional complaints, well-being, mortality and morbidity. In the sample of patients who survived 10 years (n = 23), morbidity (infections, malignancies, graft arteriosclerosis, and rejection episodes) as well as quality of life were evaluated. RESULTS: Actuarial survival rates were 83.3, 66.7, 48.3% at 1, 5, and 10 years after transplantation, respectively. During the first year, infections were the most important reasons for premature death. As a cause of mortality, malignancies were found between years 1 and 5, and graft arteriosclerosis between years 5 and 10. Physical complaints diminished significantly after the operation, but grew significantly during the period from 5 to 10 years (p < 0.001). However, trembling (p < 0.05) and paraesthesies (p < 0.01) diminished continuously. Emotional complaints such as depression and dysphoria (both p < 0.05) increased until the tenth year after their nadir at year 1. In long-time survivors, 3 malignancies (lung, skin, thyroidea) were diagnosed 6 to 9 years postoperatively. Three patients (13%) had signs of graft arteriosclerosis at year 10; 9 (40%) patients suffered from rejection episodes during the course of 10 years. There were no serious rejection episodes deserving immediate therapy. Quality of life at 10 years is good in these patients. CONCLUSIONS: Heart transplantation is a successful therapy for patients with terminal heart disease. Long-term survivors feel well after 10 years and report a good quality of life.

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We investigated the feasibility in rats of enhancing skin-flap prefabrication with subdermal injections of adenovirus-encoding vascular endothelial growth factor (Ad-VEGF). The left saphenous vascular pedicle was used as a source for vascular induction. A peninsular abdominal flap (8 x 8 cm) was elevated as distally based, keeping the epigastric vessels intact on both sides. After the vascular pedicle was tacked underneath the abdominal flap, 34 rats were randomly divided into three groups according to treatment protocol. The implantation site around the pedicle was injected with Ad-VEGF in group I (n = 10), with adenovirus-encoding green fluorescent protein (Ad-GFP) in control group I (n = 14), and with saline in control group II (n = 10). All injections were given subdermally at four points around the implanted vessel by an individual blinded to the treatment protocol. The peninsular flap was sutured in its place, and 4 weeks later, an abdominal island flap based solely on the implanted vessels was elevated. The prefabricated island flap was sutured back, and flap viability was evaluated on day 7. Skin specimens were stained with hematoxylin and eosin for histological evaluation. In two rats from each group, microangiography was performed to visualize the vascularity of the prefabricated flaps. There was a significant increase in survival of prefabricated flaps in the Ad-VEGF group compared to the control groups: Ad-VEGF, 88.9 +/- 6.1% vs. Ad-GFP, 65.6 +/- 9.4% (P < 0.05) and saline, 56.0 +/- 3.4% (P < 0.05). Sections from four prefabricated flaps treated with Ad-GFP revealed multiple sites of shiny deposits of green fluorescent protein around the area of local administration 1 day and 3 weeks after gene therapy. Histological examination done under high-power magnification (x400) with a light microscope revealed increased vascularity and mild inflammation surrounding the implanted vessel in all groups. However, we were unable to demonstrate any significant quantitative difference with respect to vascularity and inflammatory infiltrates in prefabricated flaps treated with Ad-VEGF compared with controls. Microangiographic studies showed increased vascularity around the implanted pedicle, which was similar in all groups. However, vascularization was distributed in a larger area in the prefabricated flaps treated with Ad-VEGF. In this study, the authors demonstrated that adenovirus-mediated VEGF gene therapy increased the survival of prefabricated flaps, suggesting that it may allow prefabrication of larger flaps and have the potential to reduce the time required for flap maturation.

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The introduction of cyclosporine A (CyA) into the immunosuppressive therapy has significantly improved the results of heart transplantation (HTX). Its nephrotoxicity and hepatotoxicity, however, often limit the perioperative and postoperative use of this drug. The purpose of this retrospective study was to evaluate the effect of early postoperative CyA blood levels on the incidence of early as well as late cardiac rejection and patients' survival. Between October 1985 and June 1991, HTX was performed in 311 patients. Standard immunosuppression consisted of azathioprine (1-2 mg/kg), prednisolone (0.5 to 0.1 mg/kg) and CyA. Rabbit-antithymocyte-globulin (RATG - 1.5 mg/kg) was administered for the first 4 days postoperatively. Moderate rejection was treated with 3 x 500 mg methylprednisolone, severe rejection with RATG (1.5 mg/kg three times a day). Patients were excluded from this study because of a positive cross-matching, early death unrelated to rejection or alternate forms of immunosuppression (n = 111). Follow-up was complete in 200 patients (mean age 44 +/- 11; 18 female, 182 male; 204,233 patient days) with a total of 5380 biopsies. The cohort was divided into group I (no CyA for day 0 to 2; n = 108) and group II (CyA during day 0 to 2; n = 92) according to the onset of CyA therapy. In 101 patients (group A) the mean CyA blood level was less than 150 ng/ml from day 0 to 14 and in 99 patients more than 150 ng/ml (group B).(ABSTRACT TRUNCATED AT 250 WORDS)

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BACKGROUND: Renal resistance index, a predictor of kidney allograft function and patient survival, seems to depend on renal and peripheral vascular compliance and resistance. Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of nitric oxide synthase and therefore influences vascular resistance. STUDY DESIGN: We investigated the relationship between renal resistance index, ADMA, and risk factors for cardiovascular diseases and kidney function in a cross-sectional study. SETTING ; PARTICIPANTS: 200 stable renal allograft recipients (133 men and 67 women with a mean age of 52.8 years). PREDICTORS: Serum ADMA concentration, pulse pressure, estimated glomerular filtration rate and recipient age. OUTCOME: Renal resistance index. MEASUREMENTS: Renal resistance index measured by color-coded duplex ultrasound, serum ADMA concentration measured by liquid chromatography-tandem mass spectrometry, estimated glomerular filtration rate (Nankivell equation), arterial stiffness measured by digital volume pulse, Framingham and other cardiovascular risk factors, and evaluation of concomitant antihypertensive and immunosuppressive medication. RESULTS: Mean serum ADMA concentration was 0.72 +/- 0.21 (+/-SD) micromol/L and mean renal resistance index was 0.71 +/- 0.07. Multiple stepwise regression analysis showed that recipient age (P < 0.001), pulse pressure (P < 0.001), diabetes (P < 0.01) and ADMA concentration (P < 0.01) were independently associated with resistance index. ADMA concentrations were correlated with estimated glomerular filtration rate (P < 0.01). LIMITATIONS: The cross-sectional nature of this study precludes cause-effect conclusions. CONCLUSIONS: In addition to established cardiovascular risk factors, ADMA appears to be a relevant determinant of renal resistance index and allograft function and deserves consideration in prospective outcome trials in renal transplantation.

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Canine transmissible venereal tumor (CTVT) is a parasitic cancer clone that has propagated for thousands of years via sexual transfer of malignant cells. Little is understood about the mechanisms that converted an ancient tumor into the world's oldest known continuously propagating somatic cell lineage. We created the largest existing catalog of canine genome-wide variation and compared it against two CTVT genome sequences, thereby separating alleles derived from the founder's genome from somatic drivers of clonal transmissibility. We show that CTVT has undergone continuous adaptation to its transmissible allograft niche, with overlapping mutations at every step of immunosurveillance, particularly self-antigen presentation and apoptosis. We also identified chronologically early somatic mutations in oncogenesis- and immune-related genes that may represent key initiators of clonal transmissibility. Thus, we provide the first insights into the specific genomic aberrations that underlie CTVT's dogged perseverance in canids around the world.

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Cutaneous malignant melanoma (CMM) is the cancer of the melanocytes, the cells that produce the pigment melanin, and is an aggressive skin cancer that is most prevalent in the white population. Although most cases of malignant melanoma are white, black and other non-white populations also develop this disease. However, the etiologic factors involved in the development of melanoma in these lower-risk populations are not well known. Generally, survival rates of malignant melanoma have been found to be lower in blacks than for whites with similar stage of disease at diagnosis. ^ This study presents an analysis of the differences in survival between black and white cases with malignant melanoma of the skin as the only or first primary cancer, found in the National Cancer Institute Surveillance, Epidemiology and End Results (SEER) cancer registry from 1973 to 1997. A total of 54,193 cases of CMM were diagnosed in black and white patients between 1973 and 1997. Black patients tended to be older, with a mean age of 64.46 years, compared to 53.14 years for white patients. Eighty-nine percent of patients were diagnosed with CMM as the only cancer. (Abstract shortened by UMI.)^

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Signal transducer and activator of transcription 3 (Stat3) is a signaling molecule that transduces signal from cell surface receptors, itself translocates into the nucleus, binds to consensus promoter sequences and activates gene transcription. Here, we showed that Stat3 is constitutively activated in both premalignant tumors (papillomas) and squamous cell carcinomas of mouse skin that is induced by topical treatment with an initiator 7,12-dimethylbenz[a]anthracene (DMBA) followed by a tumor promoter 12-O-tetradecanoyl-phorbol-13-acetate (TPA). Additional data demonstrated that epidermal growth factor signaling contributes to the activation of Stat3 in this model. Using mice where Stat3 function is abrogated in keratinocytes via the Cre-LoxP system (K5Cre.Stat3 flox/flox), we demonstrated that Stat3 is required for de novo carcinogenesis since Stat3 deficiency leads to a complete abrogation of skin tumor development induced by DMBA and TPA. We subsequently showed that Stat3 plays a role in both the initiation and promotion stages of carcinogenesis. During initiation, Stat3 functions as an anti-apoptotic molecule for maintaining the survival of DNA-damaged keratinocyte stem cells. During promotion, Stat3 functions as a critical regulator for G1 to S phase cell cycle progression to confer selective clonal expansion of initiated cells into papillomas. On the other hand, using transgenic mice over-expressing a constitutively dimerized form of Stat3 (Stat3C) in keratinocytes (K5.Stat3C), we revealed a role for Stat3 in tumor progression. After treatment with DMBA and TPA, K5.Stat3C transgenic mice developed skin tumors with a shorter latency when 100% bypassed the premalignant stage and became carcinoma in situ. Histological and immunohistochemical analysis revealed these tumors as highly vascularized and poorly differentiated. More strikingly, these tumors exhibited invasion into surrounding mesenchymal tissue, some of which metastasized into lung. The tumor-mesenchymal front was characterized by partial loss of E-cadherin and elevation of vimentin, markers characterizing epithelial-mesenchymal transition. On the other hand, inhibition of Stat3 via a decoy oligonucleotide led to a significant reduction of tumor size in approximately 50% of all papillomas tested. In conclusion, we demonstrated that Stat3 plays a critical in all three stages (initiation, promotion and progression) of skin carcinogenesis, and it may potentially become a good target for cancer prevention and anti-cancer therapy. ^

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Background. Colorectal cancer (CRC) is the third most commonly diagnosed cancer (excluding skin cancer) in both men and women in the United States, with an estimated 148,810 new cases and 49,960 deaths in 2008 (1). Racial/ethnic disparities have been reported across the CRC care continuum. Studies have documented racial/ethnic disparities in CRC screening (2-9), but only a few studies have looked at these differences in CRC screening over time (9-11). No studies have compared these trends in a population with CRC and without cancer. Additionally, although there is evidence suggesting that hospital factors (e.g. teaching hospital status and NCI designation) are associated with CRC survival (12-16), no studies have sought to explain the racial/ethnic differences in survival by looking at differences in socio-demographics, tumor characteristics, screening, co-morbidities, treatment, as well as hospital characteristics. ^ Objectives and Methods. The overall goals of this dissertation were to describe the patterns and trends of racial/ethnic disparities in CRC screening (i.e. fecal occult blood test (FOBT), sigmoidoscopy (SIG) and colonoscopy (COL)) and to determine if racial/ethnic disparities in CRC survival are explained by differences in socio-demographic, tumor characteristics, screening, co-morbidities, treatment, and hospital factors. These goals were accomplished in a two-paper format.^ In Paper 1, "Racial/Ethnic Disparities and Trends in Colorectal Cancer Screening in Medicare Beneficiaries with Colorectal Cancer and without Cancer in SEER Areas, 1992-2002", the study population consisted of 50,186 Medicare beneficiaries diagnosed with CRC from 1992 to 2002 and 62,917 Medicare beneficiaries without cancer during the same time period. Both cohorts were aged 67 to 89 years and resided in 16 Surveillance, Epidemiology and End Results (SEER) regions of the United States. Screening procedures between 6 months and 3 years prior to the date of diagnosis for CRC patients and prior to the index date for persons without cancer were identified in Medicare claims. The crude and age-gender-adjusted percentages and odds ratios of receiving FOBT, SIG, or COL were calculated. Multivariable logistic regression was used to assess race/ethnicity on the odds of receiving CRC screening over time.^ Paper 2, "Racial/Ethnic Disparities in Colorectal Cancer Survival: To what extent are racial/ethnic disparities in survival explained by racial differences in socio-demographics, screening, co-morbidities, treatment, tumor or hospital characteristics", included a cohort of 50,186 Medicare beneficiaries diagnosed with CRC from 1992 to 2002 and residing in 16 SEER regions of the United States which were identified in the SEER-Medicare linked database. Survival was estimated using the Kaplan-Meier method. Cox proportional hazard modeling was used to estimate hazard ratios (HR) of mortality and 95% confidence intervals (95% CI).^ Results. The screening analysis demonstrated racial/ethnic disparities in screening over time among the cohort without cancer. From 1992 to 1995, Blacks and Hispanics were less likely than Whites to receive FOBT (OR=0.75, 95% CI: 0.65-0.87; OR=0.50, 95% CI: 0.34-0.72, respectively) but their odds of screening increased from 2000 to 2002 (OR=0.79, 95% CI: 0.72-0.85; OR=0.67, 95% CI: 0.54-0.75, respectively). Blacks and Hispanics were less likely than Whites to receive SIG from 1992 to 1995 (OR=0.75, 95% CI: 0.57-0.98; OR=0.29, 95% CI: 0.12-0.71, respectively), but their odds of screening increased from 2000 to 2002 (OR=0.79, 95% CI: 0.68-0.93; OR=0.50, 95% CI: 0.35-0.72, respectively).^ The survival analysis showed that Blacks had worse CRC-specific survival than Whites (HR: 1.33, 95% CI: 1.23-1.44), but this was reduced for stages I-III disease after full adjustment for socio-demographic, tumor characteristics, screening, co-morbidities, treatment and hospital characteristics (aHR=1.24, 95% CI: 1.14-1.35). Socioeconomic status, tumor characteristics, treatment and co-morbidities contributed to the reduction in hazard ratios between Blacks and Whites with stage I-III disease. Asians had better survival than Whites before (HR: 0.73, 95% CI: 0.64-0.82) and after (aHR: 0.80, 95% CI: 0.70-0.92) adjusting for all predictors for stage I-III disease. For stage IV, both Asians and Hispanics had better survival than Whites, and after full adjustment, survival improved (aHR=0.73, 95% CI: 0.63-0.84; aHR=0.74, 95% CI: 0.61-0.92, respectively).^ Conclusion. Screening disparities remain between Blacks and Whites, and Hispanics and Whites, but have decreased in recent years. Future studies should explore other factors that may contribute to screening disparities, such as physician recommendations and language/cultural barriers in this and younger populations.^ There were substantial racial/ethnic differences in CRC survival among older Whites, Blacks, Asians and Hispanics. Co-morbidities, SES, tumor characteristics, treatment and other predictor variables contributed to, but did not fully explain the CRC survival differences between Blacks and Whites. Future research should examine the role of quality of care, particularly the benefit of treatment and post-treatment surveillance, in racial disparities in survival.^

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Breast cancer is the most common non-skin cancer and the second leading cause of cancer-related death in women in the United States. Studies on ipsilateral breast tumor relapse (IBTR) status and disease-specific survival will help guide clinic treatment and predict patient prognosis.^ After breast conservation therapy, patients with breast cancer may experience breast tumor relapse. This relapse is classified into two distinct types: true local recurrence (TR) and new ipsilateral primary tumor (NP). However, the methods used to classify the relapse types are imperfect and are prone to misclassification. In addition, some observed survival data (e.g., time to relapse and time from relapse to death)are strongly correlated with relapse types. The first part of this dissertation presents a Bayesian approach to (1) modeling the potentially misclassified relapse status and the correlated survival information, (2) estimating the sensitivity and specificity of the diagnostic methods, and (3) quantify the covariate effects on event probabilities. A shared frailty was used to account for the within-subject correlation between survival times. The inference was conducted using a Bayesian framework via Markov Chain Monte Carlo simulation implemented in softwareWinBUGS. Simulation was used to validate the Bayesian method and assess its frequentist properties. The new model has two important innovations: (1) it utilizes the additional survival times correlated with the relapse status to improve the parameter estimation, and (2) it provides tools to address the correlation between the two diagnostic methods conditional to the true relapse types.^ Prediction of patients at highest risk for IBTR after local excision of ductal carcinoma in situ (DCIS) remains a clinical concern. The goals of the second part of this dissertation were to evaluate a published nomogram from Memorial Sloan-Kettering Cancer Center, to determine the risk of IBTR in patients with DCIS treated with local excision, and to determine whether there is a subset of patients at low risk of IBTR. Patients who had undergone local excision from 1990 through 2007 at MD Anderson Cancer Center with a final diagnosis of DCIS (n=794) were included in this part. Clinicopathologic factors and the performance of the Memorial Sloan-Kettering Cancer Center nomogram for prediction of IBTR were assessed for 734 patients with complete data. Nomogram for prediction of 5- and 10-year IBTR probabilities were found to demonstrate imperfect calibration and discrimination, with an area under the receiver operating characteristic curve of .63 and a concordance index of .63. In conclusion, predictive models for IBTR in DCIS patients treated with local excision are imperfect. Our current ability to accurately predict recurrence based on clinical parameters is limited.^ The American Joint Committee on Cancer (AJCC) staging of breast cancer is widely used to determine prognosis, yet survival within each AJCC stage shows wide variation and remains unpredictable. For the third part of this dissertation, biologic markers were hypothesized to be responsible for some of this variation, and the addition of biologic markers to current AJCC staging were examined for possibly provide improved prognostication. The initial cohort included patients treated with surgery as first intervention at MDACC from 1997 to 2006. Cox proportional hazards models were used to create prognostic scoring systems. AJCC pathologic staging parameters and biologic tumor markers were investigated to devise the scoring systems. Surveillance Epidemiology and End Results (SEER) data was used as the external cohort to validate the scoring systems. Binary indicators for pathologic stage (PS), estrogen receptor status (E), and tumor grade (G) were summed to create PS+EG scoring systems devised to predict 5-year patient outcomes. These scoring systems facilitated separation of the study population into more refined subgroups than the current AJCC staging system. The ability of the PS+EG score to stratify outcomes was confirmed in both internal and external validation cohorts. The current study proposes and validates a new staging system by incorporating tumor grade and ER status into current AJCC staging. We recommend that biologic markers be incorporating into revised versions of the AJCC staging system for patients receiving surgery as the first intervention.^ Chapter 1 focuses on developing a Bayesian method to solve misclassified relapse status and application to breast cancer data. Chapter 2 focuses on evaluation of a breast cancer nomogram for predicting risk of IBTR in patients with DCIS after local excision gives the statement of the problem in the clinical research. Chapter 3 focuses on validation of a novel staging system for disease-specific survival in patients with breast cancer treated with surgery as the first intervention. ^