Home About us Contact
|
Home About us Contact | ||
|
|
||
Multivariate Cox Model (multivariate + cox_model)
Selected AbstractsPrediction of survival in patients with head and neck cancerHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 9 2001Robert Jan Baatenburg de Jong PhD Abstract Background In patients with head and neck squamous cell carcinoma (HNSCC) the estimated prognosis is usually based on the TNM classification. The relative weight of the three contributing parameters is often not completely clear. Moreover, the impact of other important clinical variables such as age, gender, prior malignancies, etc is very difficult to substantiate in daily clinical practice. The Cox-regression model allows us to estimate the effect of different variables simultaneously. The purpose of this study was to design a model for application in new HNSCC patients. In our historical data-base of patients with HNSCC, patient, treatment, and follow-up data are stored by trained oncological data managers. With these hospital-based data, we developed a statistical model for risk assessment and prediction of overall survival. This model serves in clinical decision making and appropriate counseling of patients with HNSCC. Patients and Methods All patients with HNSCC of the oral cavity, the pharynx, and the larynx diagnosed in our hospital between 1981 and 1998 were included. In these 1396 patients, the prognostic value of site of the primary tumor, age at diagnosis, gender, T-, N-, and M-stage, and prior malignancies were studied univariately by Kaplan-Meier curves and the log-rank test. The Cox-regression model was used to investigate the effect of these variables simultaneously on overall survival and to develop a prediction model for individual patients. Results In the univariate analyses, all variables except gender contributed significantly to overall survival. Their contribution remained significant in the multivariate Cox model. Based on the relative risks and the baseline survival curve, the expected survival for a new HNSCC patient can be calculated. Conclusions It is possible to predict survival probabilities in a new patient with HNSCC based on historical results from a data-set analyzed with the Cox-regression model. The model is supplied with hospital-based data. Our model can be extended by other prognostic factors such as co-morbidity, histological data, molecular biology markers, etc. The results of the Cox-regression may be used in patient counseling, clinical decision making, and quality maintenance. © 2001 John Wiley & Sons, Inc. Head Neck 23: 718,724, 2001. [source] Pleural fluid findings as prognostic factors for malignant pleural mesotheliomaJOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 5 2008Tanseli Efeoglu Gonlugur Abstract The aim of this study was to determine the prognostic value of pleural fluid glucose, lactate dehydrogenase (LDH), albumin, total protein, and total leukocyte levels in patients with malignant pleural mesothelioma. We retrospectively analyzed 71 consecutive patients (33 men and 38 women) who were referred to the department of chest diseases in a university hospital. Pleural fluid glucose levels, the ratio of pleural fluid to serum LDH>1.0, and total leukocyte count were significant predictors for the survival in univariate analysis. However, none of these variables emerged as statistically significant from the multivariate Cox model. In conclusion, our results showed that there is an inverse correlation between the intensity of inflammation and survival. J. Clin. Lab. Anal. 22:334,336, 2008. © 2008 Wiley-Liss, Inc. [source] Prognostic factors for patients with cirrhosis and kidney dysfunction in the era of MELD: results of a prospective studyLIVER INTERNATIONAL, Issue 7 2006Michael Schepke Abstract: Background/Aim: Hepatorenal syndrome (HRS) is associated with a poor prognosis. The incidence and prognostic impact of kidney dysfunction due to other causes in cirrhotic patients are less well known. The current study prospectively evaluated the incidence and the prognostic relevance of different etiologies of kidney failure in cirrhotic patients. Methods: Eighty-eight consecutive patients with cirrhosis and serum creatinine ,1.5 mg/dl were enrolled. The etiologies of kidney dysfunction were analyzed, and prognostic factors including Model for End-Stage Liver Disease (MELD) score were evaluated in a multivariate Cox model. Results: HRS was present in 35 (40%) patients (15 HRS 1, 20 HRS 2), followed by renal parenchymal disease (23%), drug-induced kidney dysfunction (19%) and prerenal failure due to bleeding or infections (15%). HRS patients had a significantly higher MELD score and shorter survival. In addition to the MELD score, only HRS 1 was independently predictive for survival. HRS 2 patients had a similar outcome as patients with non-HRS kidney dysfunction. Conclusions: In patients with cirrhosis and renal failure, hepatorenal syndrome is associated with a worse prognosis than kidney dysfunction due to other conditions but only HRS type 1 has independent prognostic relevance in addition to the MELD score in these patients. [source] Recovery Factors Affecting Utilization of Small Pediatric Donor KidneysAMERICAN JOURNAL OF TRANSPLANTATION, Issue 1 2009L. K. Kayler Kidneys from small pediatric donors are underutilized. Using data from the Scientific Registry of Transplant Recipients for donors <21 kg in which at least one organ was recovered from 1997 to 2007 (n = 3341), donor and recovery factors were evaluated by multivariate analysis for associations with (a) kidney nonrecovery and (b) transplantation of recovered kidneys. Results: The proportion of kidney recoveries were 55% during liver procurements and 40% during intestine procurements amongst donors <10 kg (p < 0.01) compared to 93% and 88%, respectively, for donors weighing 10,20 kg (p = 0.003). Intestine procurement was independently associated with an 81% greater likelihood of kidney nonrecovery (p < 0.0001) and a 48% lower likelihood of transplantation (p = 0.0004). A multivariate Cox model indicated that single kidney recipients had a 63% higher risk of graft failure compared with en bloc kidney recipients (p < 0.0001); however, concurrent intestine recovery was not a significant risk factor for graft loss. Intestine recovery from donors <21 kg of age is strongly associated with higher kidney nonrecovery and lower transplantation rates. Graft survival is worse with single kidney transplantation, but is not significantly affected by intestine recovery. Small pediatric donors procurement teams should strive to increase kidney recoveries overall and en bloc recoveries in particular. [source] COPS3 amplification and clinical outcome in osteosarcomaCANCER, Issue 9 2007Taiqiang Yan MD Abstract BACKGROUND. Amplification of several genes that map to a region of chromosome 17p11.2, including COPS3, was observed in high-grade osteosarcoma. These genes were also shown to be overexpressed and may be involved in osteosarcoma tumorigenesis. COPS3 encodes a subunit of the COP9 signalosome implicated in the ubiquitination and ultimately degradation of the P53 tumor suppressor. To determine the relation between COPS3 amplification, P53 mutation, and patient outcome in osteosarcoma, tumors from a large cohort of patients with high-grade osteosarcoma and long-term clinical follow-up were examined. METHODS. Quantitative real-time polymerase chain reaction (PCR) was performed to detect copy number changes for COPS3, as well as additional genes (NCOR1, TOM1L2, and PMP22) from the 17p11.2 amplicon, in 155 osteosarcomas from a prospective collection of tumors with corresponding clinical data. Univariate and multivariate analyses were performed to assess differences in survival between groups. RESULTS. Amplification of COPS3, detected in 31% of the osteosarcomas, was strongly associated with large tumor size (P = .0009), but was not associated with age at diagnosis, site, sex, and tumor necrosis. COPS3 amplification was significantly correlated with a shorter time to metastasis with an estimated hazard ratio (HR) of 1.61 (95% confidence interval [CI], 1.02,2.55) in univariate analysis (log-rank test, P = .042). However, in an a priori multivariate Cox model including the other clinical parameters, the HR for COPS3 amplification decreased to 1.32 (95% CI, 0.82,2.13, P = .25), mainly due to the strong correlation with tumor size. COPS3 amplification and P53 mutation frequently occurred in the same tumors, suggesting that these are not mutually exclusive events in osteosarcoma. Although not statistically significant, patients whose tumors exhibited both molecular alterations tended to be more likely to develop metastasis compared with patients with either COPS3 amplification or P53 mutation alone. CONCLUSIONS. COPS3 is the likely target of the 17p11.2 amplicon. COPS3 may function as an oncogene in osteosarcoma, and an increased copy number may lead to an unfavorable prognosis. Cancer 2007. © 2007 American Cancer Society. [source] Development of prognostic factors and survival in cutaneous melanoma over 25 yearsCANCER, Issue 3 2005An analysis of the Central Malignant Melanoma Registry of the German Dermatological Society Abstract BACKGROUND Recent studies revealed that incidence rates of cutaneous melanoma (CM) were leveling off predominantly among younger people and patterns suggested birth-cohort effects. The current study analyzed the development of prognostic factors and survival in incident CM over 25 years. METHODS All 45,483 patients with incident CM diagnosed between 1976 and 2000 recorded by the German Central Malignant Melanoma Registry were considered. Linear and logistic regression analyses were used to judge time trends. Trends of survival rates were tested with the multivariate Cox model. RESULTS Median tumor thickness decreased from 1.81 mm in 1976 to 0.53 mm in 2000 (P < 0.0001). The percentages of in situ and level II CM increased, respectively (P < 0.0001). The percentage of ulcerated CM decreased (P < 0.0001). The percentage of superficial spreading melanoma increased, whereas the percentage of nodular melanoma decreased (P < 0.0001). These time trends were all significant in the strata of gender, however, male patients presented in general with more advanced disease. Between 1976 and 2000, the average patient got older (P < 0.0001). The percentage of patients diagnosed with the primary tumor alone increased (P < 0.0001). Across the 25 years of observation, adjusted survival rates did not increase for females (P = 0.1561) but they increased for males (P < 0.0001). CONCLUSIONS The data demonstrated a strong trend towards prognostically more favorable CM most likely due to earlier diagnosis. Men and older people should be the focus of health promotion activities as they presented with more advanced disease. Cancer 2005. © 2005 American Cancer Society. [source] | ||||||||||