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Non-seminomatous testicular cancer clinical stage I: prediction of outcome by histopathological parameters. A multivariate analysis.

The clinical course of 186 orchiectomized patients with testicular non-seminoma clinical stage I (CSI) was reviewed together with a reevaluation of the haematoxylin-eosin-stained histological sections of the primary tumour. Treatment (1970-1980) was as follows: abdominal radiotherapy (group 1): 132 patients; observation only (group 2): 23 patients; retroperitoneal lymph node dissection (group 3): 31 patients. Failure of the management (diagnostic error/relapse after treatment) was defined as demonstration of retroperitoneal lymph node metastases (group 3) or relapse during follow-up (group 2 and 3). Ten of the 31 primarily operated patients had retroperitoneal lymph node metastases. (These patients received 3-4 cycles adjuvant cisplatin based on chemotherapy.) Forty-six patients relapsed after a median time of 6 months (range: 2-113). The 10-year cancer-related survival rates for group 1 and 2 were 85 and 73%, respectively. No cancer-related death occurred in group 3 within the first 5 years. In a univariate analysis the following parameters were significantly (p less than 0.05) correlated with management failure: vascular invasion (blood, lymphatic), the presence of syncytiotrophoblasts, the demonstration of the histological subtype MTU. In a multivariate analysis both lymphatic and blood vessel invasion significantly predicted management failure. In 80% of the non-seminoma patients with CSI and both lymphatic and blood vessels invasion in the primary tumour failure of the primary management must be expected. In the multivariate analysis the demonstration of MTU was a predictive factor only if no differentiation was made between lymphatic and blood vessel invasion. The presence or absence of endodermal sinus tumour was not correlated with the failure rate in non-seminoma CSI. Based on easily assessable histopathological parameters of the primary tumour (small vessel invasion in particular) it is possible to define subgroups of patients with non-seminoma CSI who have a high or a low risk of relapse or who are likely to have microscopic retroperitoneal lymph node metastases. Such a differentiation should have therapeutic consequences.

Humans

Radical surgery (R2 resection) for gastric cancer. A multivariate analysis.

BACKGROUND: Extended lymphadenectomy remains controversial in the Western world. Its evaluation and the identification of high-risk patients after surgery are important tasks. METHODS: A retrospective prognostic study of 318 patients treated for potential cure of gastric cancer was performed. All patients underwent extended lymphadenectomy. Clinical histopathologic and surgical factors were examined for their influence on survival by univariate and multivariate analysis. RESULTS: Postoperative mortality was 4.4% (14 of 318), and the 5-year adjusted survival rate was 57.8%. Multivariate analysis using the Cox model identified seven factors as having independent influence on survival. Detrimental factors were male gender, age over 65 years, high pN category, increasing number of lymph nodes invaded by metastases, total gastric resection, splenectomy, and increasing number of perioperatively required blood units. CONCLUSION: Extended lymphadenectomy was possible without sacrificing low postoperative mortality rates. The importance of certain prognostic factors, in particular lymph node status, could be confirmed.

Aged

Prognostic value of CEA and ferritin assay in breast cancer: a multivariate analysis.

The prognostic significance of preoperative serum carcinoembryonic antigen (CEA) and ferritin levels was evaluated in 191 women operated for breast cancer. The influence of CEA, ferritin and another 11 clinical and pathological features on the disease-free survival was investigated in a multivariate analysis, using Cox's proportional hazard model. Axillary node status (P = 0.004), CEA level (P = 0.011), and the histological grade of the tumor (P = 0.029) emerged as independent prognostic factors. By contrast, no significant relationship was found between ferritin and disease-free survival. These three parameters were used to derive a prognostic index (I) for each patient. Multivariate analysis showed that its prognostic value was better than the value of any single factor (P less than 0.0001). The I score was used to divide patients into groups at different risk of recurrence: low, moderate and high (97.5%, 45% and 22.5% of recurrence-free patients at 3 years respectively). The data showed that the prognosis of patients with different combinations of node status and tumor grade was related to the level of CEA. Only women with very good (node-negative with well-differentiated tumors) or very bad prognosis (node-positive with four or more metastatic nodes and poorly differentiated tumors) had a disease-free survival independent of CEA values. These findings suggest that the preoperative measurement of CEA enhances the possibility of correctly predicting outcome and hence could be of assistance in the planning of adjuvant therapies.

Adult

Factors determining the occurrence of late potentials on the signal-averaged electrocardiogram after a first myocardial infarction: a multivariate analysis.

To determine the natural history of late potentials on the signal-averaged electrocardiogram (ECG), multivariate analysis was performed in 167 patients (138 men, 29 women) with a first anterior or inferior acute myocardial infarction. Seventy-four patients received thrombolytic therapy; the remaining 93 patients were treated conventionally. All patients underwent coronary angiography, left ventricular ejection fraction determination and signal-averaged ECG recording. Eight variables thought to be correlated with the presence of late potentials were studied; that is, age, infarct location, number of diseased coronary vessels, left ventricular ejection fraction, infarct-related coronary artery patency, treatment received, delay between admission and signal-averaged recording and delay between admission and coronary angiography. Statistical analysis showed that two independent factors (coronary artery occlusion and impaired left ventricular ejection fraction) were highly correlated with the incidence of late potentials. The occurrence of late potentials was multiplied by 5 in case of an occluded infarct-related vessel and by 1.75 each time the left ventricular ejection fraction value decreased by 0.10. This study suggests that coronary artery patency is the most important factor that decrease the rate of late potentials after a first acute myocardial infarction and it occurs independently of infarct location and left ventricular function.

Coronary Angiography

Subjective multivariable analysis bu computer for evaluation of coronary artery bypass.

Subjective multivariable analysis by computer was utilized to evaluate the results in a series of 659 patients undergoing coronary artery saphenous vein bypass surgery. A video terminal gave access to a remote computer. The postoperative subjective response was evaluated by questionnaires sent to patients at 6- to 12-month intervals, and was augmented by treadmill testing and postoperative coronary arteriography. Operative risk and subjective response are related only to the degree of ventricular function lost prior to surgery. Long-term results were best in patients in whom complete revascularization was possible. Current operative risk is less than 1%; a five-year survival rate of 90% to 95% is predicted. More than 90% of patients were asymptomatic or "greatly improved." Postoperative treadmill tests were negative in 88% of patients in these groups. In patients who were only "slightly improved" or "not improved," repeat catherization showed a graft patency rate of 84%, suggesting that recurrent symptoms were related to the extent of preoperative disease or to the progression of disease in nongrafted vessels, rather than to graft occlusion.

Computers

Treatment of oesophageal perforation: a multivariate analysis.

Perforation of the oesophagus was retrospectively analysed in 59 patients. Cause and extent of perforation, localization, quality of the oesophageal wall and therapeutic modes were subjected to univariate analysis. The perforations of the intrathoracic oesophagus (39) were also subjected to multivariate analysis. Perforation of the cervical oesophagus is seldom lethal and can be adequately treated conservatively in the majority of cases. Perforations of the intrathoracic oesophagus can be divided into two groups, with or without simultaneous perforation of the parietal pleura. The optimal treatment for the group with pleural perforation seems to be resection of the oesophagus and secondary reconstruction, although primary closure is indicated in selected early cases. Perforations of the intrathoracic oesophagus confined to the mediastinum can be adequately treated conservatively in most patients. Perforation of the intra-abdominal oesophagus should be treated like any other intra-abdominal visceral perforation, by closure or diversion, even if this results in resection of the oesophagus.

Adolescent

The Swedish Childhood Diabetes Study--a multivariate analysis of risk determinants for diabetes in different age groups.

In a nationwide incident case-referent study stepwise univariate analysis has revealed several risk determinants for childhood diabetes mellitus. In a multivariate analysis we have determined the set of risk determinants that would independently predict childhood Type 1 (insulin-dependent) diabetes. Possible interactions between the risk determinants and differences in risk profiles with different ages at onset were also examined. Reported familial insulin-treated and non-insulin-treated diabetes were significant risk factors in all age groups, as was also a low frequency of milk intake. The frequency of infections and a high intake of foods rich in nitrosamine tended to interact (OR 11.8, p = 0.053) indicating a synergistic effect. A Cox regression analysis revealed that stressful life events during the last year was the only variable that tended to affect the age at onset (p = 0.055). This indicated that psychological stress may rather precipitate than induce Type 1 diabetes. A short breast-feeding duration (OR = 3.81), and an increased body height (OR = 3.82) contributed significantly to the predictive model in only the youngest age group (0-4 years). An increased frequency of infections in the year preceding onset (OR = 2.15) and no vaccination against measles (OR = 3.33) contributed significantly to the model only in the age group 5-9 years. Various nutrients had different impacts on the risk of developing Type 1 diabetes in different age groups. It is concluded that in the genetically susceptible child, risk factors which are associated with eating habits, frequency of infections, vaccination status, growth pattern and severe psychological stress affect the risk of developing diabetes independently of each other.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors

Multivariate analysis of operative mortality and late outcome after coronary bypass surgery.

A multivariate discriminant analysis was made to find out the variables that could offer the greatest amount of predictive power on the long term results after myocardial revascularization. A total of 202 consecutive patients who underwent CABG operation in 1981 were reviewed 5 years later. Most of the patients (76.5%) had 3-vessel disease, previous AMI (70.2%), hypertriglyceridemia (61.7%), positive family history of CAD (68.0%) elevated blood cholesterol level (48.1%), hypertension (41.9%) or were smokers (61.9%). In 48.1% of the cases IMA was used for revascularization and in the rest saphenous vein graft alone. The 5-year survival of the entire group was 87%. The late mortality was related to 3 independent variables in multivariate analysis: 1) positive family history of CAD (p less than 0.05), 2) preoperative ejection fraction less than 0.30 (p less than 0.01) and 3) revascularization without IMA (p less than 0.02). The vast majority of patients (70%) had a better NYHA class 5 years postoperatively (the 95% confidence interval was 65-77%). These patients had experienced an average improvement of 2.0 NYHA categories. Eight per cent of patients had an unaltered and 5% a worse NYHA class than preoperatively. When the patients were grouped into those having a better NYHA class and into those who had an unchanged or worse NYHA class or who had died from CAD the only variable which was associated with poorer outcome appeared to be positive family history of CAD (p less than 0.01). It can be concluded that hereditary factors, utilization of internal mammary artery in revascularization and preoperative ejection fraction are the major predictors of late outcome after CABG.

Coronary Artery Bypass

Value of flow cytometric determination of ploidy as a guide to prognosis in operable rectal cancer: a multivariate analysis.

The DNA content of 203 cases of rectal cancer, with at least 15 years follow-up, was analysed by flow cytometry. One hundred and twenty-nine (64%) were DNA aneuploid and corrected survivals were significantly influenced by ploidy distribution (p less than 0.01). The DNA content and details of stage and grade were subjected to multivariate analysis using the Cox regression model. Ploidy was entered into models including Dukes' stage alone, tumour differentiation alone, Dukes' stage and differentiation in combination and a more comprehensive range of discrete stage- and grade-related parameters. All four models demonstrated its independent contribution to survival. However, its contribution was very small (5%, 18%, 5%, 4% respectively). These findings illustrate that results based on new technological developments should not be viewed in isolation, but their values must be assessed in combination with traditionally available data by means of multivariate analysis.

Adenocarcinoma

Transitional cell carcinoma of the urethra in men following cystectomy for bladder cancer: multivariate analysis for risk factors.

Multicentric development of transitional cell carcinoma in the urinary tract is well recognized. Of 169 male patients who underwent cystectomy for bladder cancer 18 (10.6%) demonstrated urethral cancer (all within 5 years after cystectomy). The risk factors involved in transitional cell carcinoma in regard to the occurrence of urethral cancer after cystectomy were examined by multivariate analysis. Characteristic patterns of bladder cancer in the cystectomy specimens were expressed by the grade, stage, number, size, location and gross pattern of the tumors. Significant risk factors in bladder cancer relating to the development of cancer in the retained urethra were papillary cancer, multiple cancers, and tumors in the bladder neck, prostatic urethra and prostatic gland. Among 19 patients with concomitant carcinoma in situ and/or multiple papillary tumors in the bladder who underwent simultaneous prophylactic urethrectomy with cystectomy in the same observed period 17 (89%) had no lesion in the resected urethra. The results of the multivariate analysis will be useful to avoid unnecessary prophylactic urethrectomy at cystectomy. However, further analysis and consideration of possible mechanisms of the secondary urethral cancer will be necessary to explain the discrepancy posed in the latter study involving 19 patients.

Adult

Prognosis of dilated cardiomyopathy: from a retrospective to a prospective study employing multivariate analysis.

To determine the prognostic factors of dilated cardiomyopathy (DCM), a retrospective long-term investigation of 111 patients seen between 1967 and 1983 was carried out. Fifty-four deaths were divided into 3 subgroups: (1): sudden death (n = 6); (2): sudden death on the basis of heart failure (n = 17); (3): refractory heart failure death (n = 31). Multivariate analysis was employed to ascertain the prognostic score, which was constructed from the grading of the New York Heart Association functional classification, the cardiothoracic ratio, electrocardiographic findings and cardiac function. Individual variables were indicated on the first (I) and second (II) principal component axes. The mean center points for the death modes were as follows: (1): I = -0.4, II = +0.8, (2): I = +0.7, II = +1.1, (3): I = +1.4, II = -0.8. Surviving cases (n = 57) showed I = -0.6, II = +0.1. Forty-one cases examined during 1984-1985 were analyzed to evaluate the prognostic efficacy of this score. Fourteen of 17 cases (82%) located in the refractory heart failure death group died within one year after determination of the prognosis, showing thereby that the prognostic determination by multivariate analysis is effective.

Adult

[Utility of multivariate analysis in evaluating the results of health examination on the basis of intra-individual variations].

Utility of multivariate analysis in evaluating the values of laboratory tests on the basis of intra-individual variations (IV) was studied. Periodic health examination on workers has many clinical laboratory tests and these values are generally evaluated in comparison with "normal ranges." Recently it has been ascertained that the individual normal ranges were narrower than the populational normal ranges. Although the values of an individual should be estimated with normal ranges of the individual, it is almost impossible to determine the normal ranges from only one or two health examinations conducted per annum at the place of work. The author in his study could easily determine IV with a method using Mahalanobis' distance on a basis of populational normal range. In this method, if many values of a person in the tests vary in several years, the distance becomes larger, and if a value in a test falls outside the normal limit, it also becomes larger. This method makes it possible to detect not only an "abnormal" value out of the normal range but also a large value out of IV. To examine the practical validity of the method, the data of 24 employees (males, 45 to 65 years old) from 3 periodic health examinations and those of 20 persons (males, 48 to 71 years old) from 3 to 6 medical checkups were analyzed with regard to 11 items. It was found that 33 out of 44 persons were abnormal in one or more items and that 10 abnormal persons had large IV. They would be missed in the judgement with the use of only "normal ranges." As the distances were computed by a portable computer with a basic program, the method can be easily used in a small place of work. It is considered that this new method is effective and valuable not only as the screening procedure but also in the evaluation of IV.

Aged

Biochemical markers in multiple myeloma: a multivariate analysis.

The analysis of individual biochemical and clinical variables in 121 patients with multiple myeloma showed that serum beta 2-microglobulin (S-beta 2m) had the most significant relation to survival. Other variables such as serum thymidine kinase (S-TK), serum lactate dehydrogenase (S-LDH), S-creatinine, haemoglobin (Hb), ESR, S-albumin, age and clinical stage were also significant. No such relationship was found with M-component, presence of light chains in urine, type of secreted immunoglobulin or S-calcium. The exclusion of clinical stage in the first multivariate analysis resulted in a model consisting of S-beta 2m, age and S-TK, none of the other variables gave additional information. When in the second multivariate analysis the basic variables involved in staging procedure were excluded and clinical stage included, stage III, but not stage II, was found to give additional information to the model described above. Individual analysis of the variables showed that Hb had the most significant relation to effect of initial therapy. Other significant variables were S-TK, S-beta 2m and age. When using the multivariate approach, Hb alone was found to contain all the relevant information.

Adult

Multivariate analysis of antibiograms for typing Pseudomonas aeruginosa.

A method for typing Pseudomonas aeruginosa using antibiotic susceptibility patterns is presented, which allows recognition of clusters of the same strain among clinical isolates from different patients, thus indicating whether cross infection has occurred. An index of similarity (the euclidean or the oblique distance), which includes all the differences of disk zone sizes among isolates, is computed and then elaborated by a clustering algorithm that successively groups all the isolates in larger clusters. The results of clustering are presented as dendrograms, whose terminal branches are pruned down to a level below which differences are casual; isolates that still appear on a common branch are considered identical. The reliability of this technique for detecting nosocomial cross infections was assessed by comparing its results with that of serotyping and pyocin typing. Only 2 of 31 (6.4%) clusters detected by multivariate analysis were not confirmed, while 4 of 33 (12.1%) clusters were recognized by serotyping and pyocin typing, but not by multivariate analysis. In at least two instances the differences in susceptibility patterns were due to cytoplasmic R factors. The routine use of antibiogram data for typing purposes should be considered an essential part of nosocomial infection control.

Anti-Bacterial Agents

Multivariate analysis of factors affecting postoperative survival in malignant astrocytoma. Importance of DNA quantification.

Fifty-eight patients with supratentorial malignant astrocytoma were analyzed statistically to evaluate the factors most important for predicting postoperative survival. Clinical information such as age, sex, duration of preoperative symptom, Karnofsky score at admission and at discharge, location of tumor, amount of tumor removal, number of operations, and postoperative survival in months, together with data on radiation and chemotherapy were analyzed by chi square test, t-test, and multivariate analysis. Cytofluorometric DNA quantification using paraffin embedded specimens was also performed in 20 cases and these data were also evaluated. Multiple correlation coefficient, and therefore the total statistical accuracy, increased to 0.824 when data of DNA quantification, percentages of S phase cells and of polyploid cells, were included. Multivariate analysis revealed that 6 items were the major factors for predicting postoperative survival, i.e. the location of tumor, the Karnofsky score at discharge, the percentage of S phase cells, the number of operations, the percentage of polyploid cells, and the amount of tumor removed. Based on this analysis, the estimated survival time could be expressed as a formula.

Adolescent

An interactive multivariate analysis of FCM data.

The procedure and results of the interactive multivariate analysis of FCM data are described. Using principal-components analysis, cluster analysis, and interactive maneuvers, this procedure facilitates an effective data compression from a four-dimensional space into two-dimensional space, then allows cluster separation. The procedure is especially effective for separating clusters, which are degenerated in the usual scattergrams. Programs were mostly written in C language on MS-DOS and were tested on four-dimensional analysis of the blood cells, which resulted in a successful separation of the degenerated clusters.

Cell Separation

Congenital malformations and maternal occupation in Finland: multivariate analysis.

The Finnish Register of Congenital Malformations was used in a multivariate analysis to explore the associations between maternal occupation in industry and children born with central nervous system (CNS) or musculoskeletal or oral cleft malformations. Possible confounding factors were selected in preliminary screening of risk indicators for malformations. These factors included characteristics of the mother, the child, and the family; maternal illnesses; an maternal medication at the time of pregnancy. Tobacco smoking was a confounding factor for all type of malformations; number of children born to the mother, maternal age, malformations in the family, number of rooms occupied by the family, sex of the child, threatened abortion, and continuous medication of the mother during the first trimester confounded the association for certain type of malformations. After adjusting for confounding factors, maternal occupation in industrial trades significantly correlated with CNS, oral cleft, and musculoskeletal malformation in the offspring. Maternal occupation in industry and construction only was significantly associated with CNS malformations in the offspring but the associations with oral cleft and musculoskeletal malformations were not significant.

Adult

Multivariate analysis of factors influencing the results of restorative proctocolectomy.

Univariate and multivariate analysis has been used to assess the influence of 14 variables on the results of 65 consecutive ileoanal pouch procedures over 5 years. There were 9 failures requiring intubation, ileosomy or pouch excision. There was a significant association between failure and pelvic sepsis (p less than 0.05; n = 8), endoanal mucosectomy (p less than 0.05; n = 7), preservation of a long rectal cuff (p less than 0.05; n = 5) and lack of experience with the operation (p less than 0.05; n = 8). Of 49 patients with preoperative evidence of ulcerative colitis, 3 are now known to have Crohn's disease. The only factor having a significant adverse influence on complications was endoanal mucosectomy (p less than 0.01). Functional outcome was significantly impaired in patients who developed pelvic sepsis (p less than 0.001), a post-operative fistula (p less than 0.05) and who had an endoanal mucosectomy (p less than 0.05). Success with ileo-anal pouch reconstruction increases with experience. Avoidance of sepsis is associated with a lower failure rate, improved functional results and reduced hospital stay. Preliminary colectomy is also advised to exclude Crohn's disease if the diagnosis is in question.

Adult