Biomedical subjects

A Kramar

Publications and source records attributed to A Kramar.

At least 19 recordsLinked to original sources

PubMed2006

Measuring agreement for ordered ratings in 3 x 3 tables.

OBJECTIVES: When two raters consider a qualitative variable ordered according to three categories, the qualitative agreement is commonly assessed with a symmetrically weighted kappa statistic. However, these statistics can present paradoxes, since they may be insensitive to variations of either complete agreements or disagreements. METHODS: Agreement may be summarized by the relative amounts of complete agreements, partial and maximal disagreements beyond chance. Fixing the marginal totals and the trace, we computed symmetrically weighted kappa statistics and we developed a new statistic for qualitative agreements. Data sets from the literature were used to illustrate the methods. RESULTS: We show that agreement may be better assessed with the unweighted kappa index, kappa(c), and a new statistic zeta, which assesses the excess of maximal disagreements with respect to the partial ones, and does not depend on a particular weighting system. When zeta is equal to zero, maximal and partial disagreements beyond chance are equal. With its estimated large sample variance, we compared the values of two contingency tables. CONCLUSIONS: The (kappa(c), zeta) pair is sensitive to variations in agreements and/or disagreements and enables locating the difference between two qualitative agreements. The qualitative agreement is better with increasing values of kappa(c) and zeta.

Data Interpretation, Statistical↗

PubMed2005

A randomised trial of high-dose chemotherapy in the salvage treatment of patients failing first-line platinum chemotherapy for advanced germ cell tumours.

BACKGROUND: Incomplete remission or relapse from first-line chemotherapy has poor prognosis in male germ cell tumour patients. This phase III randomised trial compares conventional salvage to high-dose-intensification chemotherapy. PATIENTS AND METHODS: Between February 1994 and September 2001, 280 patients from 43 institutions in 11 countries, were randomly assigned to receive either four cycles of cisplatin, ifosfamide and etoposide (or vinblastine) (arm A), or three such cycles followed by high-dose carboplatin, etoposide and cyclophosphamide (CarboPEC) with haematopoietic stem cell support (arm B). RESULTS: Similar complete and partial response rates were observed in both treatment arms (56%; 95% CI 50% to 62%). There were 3% and 7% toxic deaths in arms A and B, respectively. No significant improvements with CarboPEC were observed in either 3-year event-free survival (35% versus 42%, P=0.16) or overall survival (53%; 95% CI 46% to 59%). Complete responders with CarboPEC had a significant improvement in disease-free survival (55% versus 75% at 3 years, P <0.04). CONCLUSIONS: The single cycle of high-dose salvage chemotherapy after three cycles of standard dose chemotherapy had no effect on treatment outcomes. These results suggest that data from uncontrolled studies should not be used to justify routine use of a toxic and expensive treatment without confirmation in a randomised trial.

Adolescent↗

PubMed2005

Two-part statistics with paired data.

In epidemiology, we often study data from a mixed distribution, i.e. with a clump of observations at zero and positive continuous data. Lachenbruch developed statistics for this kind of data for independent samples. These tests are the sum of one test for equality of proportions of zero values and one conditional test for the continuous distribution. This paper concerns the adaptation of these tests to paired samples. Like Lachenbruch, we developed two statistics, which tend to a two-degree-of-freedom chi2 distribution. These two-part statistics are the sum of McNemar's test for testing the equality of proportions of zero values, and the Wilcoxon signed-rank test or the paired Student's test for testing the equality of the distribution of positive values. We studied the behaviour of these tests for various proportions of zeros, and mean values of the continuous distribution. All tests are efficient when the smaller proportion of zero values corresponds to the population with the larger mean. In all other situations, the two-part statistics are superior to the others. These methods are applied to a matched case-control study of lower limb venous insufficiency.

Adult↗

PubMed2004

Concomitant use of tamoxifen with radiotherapy enhances subcutaneous breast fibrosis in hypersensitive patients.

Concomitant use of adjuvant tamoxifen (TAM) and radiation therapy (RT) is not widely accepted. We aim to assess whether this treatment is associated with an increased risk of developing subcutaneous fibrosis after conservative or radical surgery in breast cancer patients. We analysed 147 women with breast cancer treated with adjuvant RT, and who were included in the KFS 00539-9-1997/SKL 00778-2-1999 prospective study aimed at evaluating the predictive value of CD4 and CD8 T-lymphocyte apoptosis for the development of radiation-induced late effects. TAM (20 mg day(-1)) with concomitant RT was prescribed in 90 hormone receptor-positive patients. There was a statistically significant difference in terms of complication-relapse-free survival (CRFS) rates at 3 years, 48% (95% CI 37.2-57.6%) vs 66% (95% CI 49.9-78.6%) and complication-free survival (CFS) rates at 2 years, 51% (95% CI 40-61%) vs 80% (95% CI 67-89%) in the TAM and no-TAM groups, respectively. In each of these groups, the CRFS rates were significantly lower for patients with low levels of CD8 radiation-induced apoptosis, 20% (95% CI 10-31.9%), 66% (95% CI 51.1-77.6%), and 79% (95% CI 55-90.9%) for CD8 </=16, 16-24, and >24%, respectively. Similar results were observed for the CFS rates. The concomitant use of TAM with RT is significantly associated with an increased incidence of grade 2 or greater subcutaneous fibrosis; therefore, caution is needed for radiosensitive patients.

Adult↗

PubMed2004

Five-year change in statistical designs of phase II trials published in leading cancer journals.

This study compares the evolution in statistical design reporting for phase II cancer clinical trials published in the six following leading journals: American Journal of Clinical Oncology, Annals of Oncology, British Journal of Cancer, Cancer, European Journal of Cancer and Journal of Clinical Oncology. Only articles where tumour response was considered as the primary endpoint were selected. A total of 393 phase II trials published in 1995 (n=185) and 2000 (n=208) were reviewed. Neither sample size nor design parameters were specified in 157 (85%) and 113 (46%) papers in 1995 and 2000, respectively. 28 (15%) and 95 (46%) papers included at least some information on the statistical designs used: Gehan (4.3% and 3.3%), Fleming (2.2% and 4.3%), and Simon (2.7% and 11.0%). Ad hoc, non-referenced methods were used in 5.9% and 27.3% articles in 1995 and 2000, respectively. Although there is an increase in the mention of at least some statistical design parameters in phase II cancer clinical trials over a 5-year period in these selected cancer journals, the use of referenced methods is still short or often inadequate.

Clinical Trials, Phase II as Topic↗

PubMed2003

Potentiation of ionising radiation by targeting tumour necrosis factor alpha using a bispecific antibody in human pancreatic cancer.

The aim of this study was to treat carcinoembryonic antigen (CEA)-expressing pancreatic carcinoma cells with tumour necrosis factor alpha (TNFalpha) and simultaneous radiation therapy (RT), using a bispecific antibody (BAb) anti-TNFalpha/anti-CEA. TNFalpha used alone produced a dose-dependent inhibition of the clonogenic capacity of the cultured cells. Flow cytometry analysis of cell cycle progression confirmed the accumulation of cells in G(1) phase after exposure to TNFalpha. When TNFalpha was added 12 h before RT, the surviving fraction at 2 Gy was 60% lower than that obtained with irradiation alone (0.29 vs 0.73, respectively, P<0.00001). In combination treatment, cell cycle analysis demonstrated that TNFalpha reduced the number of cells in radiation-induced G(2) arrest, blocked irreversibly the cells in G(1) phase, and showed an additive decrease of the number of cells in S phase. In mice, RT as a single agent slowed tumour progression as compared with the control group (P<0.00001). BAb+TNFalpha+RT combination enhanced the delay for the tumour to reach 1500 mm(3) as compared with RT alone or with RT+TNFalpha (P=0.0011). Median delays were 90, 93, and 142 days for RT alone, RT+TNFalpha, and RT+BAb+TNFalpha groups, respectively. These results suggest that TNFalpha in combination with BAb and RT may be beneficial for the treatment of pancreatic cancer in locally advanced or adjuvant settings.

Adenocarcinoma↗

PubMed2003

Statistical optimisation of diclofenac sustained release pellets coated with polymethacrylic films.

The objective of the present study was to evaluate three formulation parameters for the application of polymethacrylic films from aqueous dispersions in order to obtain multiparticulate sustained release of diclofenac sodium. Film coating of pellet cores was performed in a laboratory fluid bed apparatus. The chosen independent variables, i.e. the concentration of plasticizer (triethyl citrate), methacrylate polymers ratio (Eudragit RS:Eudragit RL) and the quantity of coating dispersion were optimised with a three-factor, three-level Box-Behnken design. The chosen dependent variables were cumulative percentage values of diclofenac dissolved in 3, 4 and 6 h. Based on the experimental design, different diclofenac release profiles were obtained. Response surface plots were used to relate the dependent and the independent variables. The optimisation procedure generated an optimum of 40% release in 3 h. The levels of plasticizer concentration, quantity of coating dispersion and polymer to polymer ratio (Eudragit RS:Eudragit RL) were 25% w/w, 400 g and 3/1, respectively. The optimised formulation prepared according to computer-determined levels provided a release profile, which was close to the predicted values. We also studied thermal and surface characteristics of the polymethacrylic films to understand the influence of plasticizer concentration on the drug release from the pellets.

Diclofenac↗

PubMed2003

Radiation-induced skin fibrosis after treatment of breast cancer: profilometric analysis.

BACKGROUND/AIM: Treatment of breast cancer involves an association of conservative surgery and radiotherapy. This implies various cutaneous complications, well known for their clinical and histological aspects. Little data are available concerning modifications of the cutaneous microrelief after radiotherapy. We have done a profilometric analysis of the skin of breast cancer patients treated with surgery and radiotherapy. The results obtained on the irradiated breast have been compared with the ones of the controlateral normal breast. METHODS: Twenty women, 43-55 year old were enrolled in the study 6-16 months after the end of a treatment associating conservative surgery and radiotherapy for breast cancer. Imprints using a silicone rubber material were performed over symmetrical areas of the treated breast and the controlateral one. All measures were performed over the upper-medial quadrant of each breast. The imprints are then blindly analysed using an image analyser. The following parameters were measured: RA (average roughness of the skin), RZ (average of the furrows depth), RS (residual length), Rn (number of furrows) and AR (space between the furrows). RESULTS: The comparison of the imprints shows important modifications of the microrelief after irradiation. We observe a slight increase of the skin roughness (RA: 26, 39 +/- 2, 58 versus 21, 84 +/- 1, 59), a significantly increase of the furrows depth (RZ: 121, 66 +/- 10, 46 versus 101, 26 +/- 6, 99) along with an increase of the residual length (RS: 580, 60 +/- 60, 60 versus 450, 46 +/- 48, 43). The number of furrows has not significantly decreased but the space between the furrows has increased on the irradiated breast. CONCLUSION: This study shows a breakdown effect of irradiation on the skin in correlation with the fibrosis inducing by ionising radiation. The imprints modifications are clearly different from those usually observed in the ageing process. Our results can be a basis for studying the effects of treatments on cutaneous complications linked to the radiation-induced fibrosis.

Adult↗

PubMed2003

An open phase I study assessing the feasibility of the triple combination: oxaliplatin plus irinotecan plus leucovorin/ 5-fluorouracil every 2 weeks in patients with advanced solid tumors.

BACKGROUND: The aim of this study was to determine the maximum-tolerated dose (MTD) and the recommended dose of irinotecan and oxaliplatin with a fixed 5-fluorouracil (5-FU)/leucovorin (LV) regimen in patients with metastatic solid tumors. PATIENTS AND METHODS: The trial was designed to evaluate escalating doses of oxaliplatin and irinotecan, starting at 60 mg/m2 and 90 mg/m2, respectively, given at day 1 with the full-dose LV5FU2 regimen, given on days 1 and 2 as follows: folinic acid 200 mg/m2 followed by 5-FU 400 mg/m2 bolus and 600 mg/m2 22 h continuous infusion, every 2 weeks. The second cohort of patients was treated at the recommended dose for oxaliplatin and irinotecan with the simplified LV5FU regimen: on day 1, a 2-h infusion of folinic acid (400 mg/m2), followed by a 10-min intravenous bolus of 5-FU (400 mg/m2), followed by a continuous infusion of 5-FU (2400 mg/m2) over 46 h. RESULTS: Thirty-four patients were treated at the following dose levels (oxaliplatin/irinotecan mg/m2): 60/90, 60/120, 85/120, 85/150, 85/180, 85/200 and 85/220 and seven patients were treated at the recommended dose with the simplified LV5FU scheme. The MTD was reached at dose level 85/220 mg/m2 but the recommended dose chosen for the second step was 85/180 mg/m2 to keep a better compliance with the biweekly schedule. Main grade 3/4 toxicities per patient included the following: neutropenia in 78% (febrile episodes in 12%), diarrhea in 27%, nausea/vomiting in 24% and peripheral neuropathy in 37% (Lévi's scale). Antitumor activity was observed at almost all dose levels. Most objective responses were observed in digestive malignancies, since 10 out of 11 were obtained in five colorectal cancers, two pancreatic cancers, two cholangiocarcinoma and one gastric cancer. CONCLUSION: The recommended dose for the triple association is 85/180 mg/m2 of oxaliplatin and irinotecan, respectively, with LV5FU2 or simplified LV5FU. The antitumor activity in gastrointestinal malignancies should be evaluated in phase II studies in different tumor types.

Adult↗

PubMed2002

High-dose, single-agent irinotecan as first-line therapy in the treatment of metastatic colorectal cancer.

PURPOSE: The efficacy and safety of single-agent, high-dose irinotecan (CPT-11, Campto) 500 mg/m(2) every 3 weeks were investigated as first-line treatment for advanced colorectal cancer (CRC). PATIENTS AND METHODS: Patients were enrolled into the study to receive a first cycle of therapy with irinotecan at a dose of 350 mg/m(2) every 3 weeks, which could be escalated to 500 mg/m(2) for the second and subsequent cycles depending on toxicity. Efficacy, safety and pharmacokinetics were determined in the intent to treat (ITT) population and the high-dose population (i.e. patients who had received at least three cycles of irinotecan, the second and third at 500 mg/m(2)). RESULTS: Of 49 patients enrolled into the study (ITT population), 31 (63%) received at least three cycles of treatment with cycles 2 and 3 at an irinotecan dose of 500 mg/m(2) (the high-dose population). The response rates (RR) for the ITT and high-dose populations were 24.5% and 35.5%, respectively. The main grade 3/4 toxicities per cycle in the ITT and high-dose populations were neutropenia 22% and 17%, febrile neutropenia 5% and 3%, and diarrhoea 12% and 7%, respectively. The pharmacokinetics of irinotecan and its metabolite SN-38 were investigated in 31 patients in cycle 1 and 22 patients in cycle 2. Irinotecan clearance and SN-38 exposure were not sufficiently correlated with toxicity in cycle 1 to identify patients for dose increase in subsequent cycles. The exposure to irinotecan and SN-38 increased in proportion to dose from 350 to 500 mg/m(2). CONCLUSION: These results suggest that high-dose irinotecan can be safely administered as first-line monotherapy to approximately two-thirds of patients who present with advanced CRC following a selective first cycle.

Adenocarcinoma↗

PubMed2001

mROC: a computer program for combining tumour markers in predicting disease states.

Receiver operating characteristic (ROC) curves are limited when several diagnostic tests are available, mainly due to the problems of multiplicity and inter-relationships between the different tests. The program presented in this paper uses the generalised ROC criteria, as well as its confidence interval, obtained from the non-central F distribution, as a possible solution to this problem. This criterion corresponds to the best linear combination of the test for which the area under the ROC curve is maximal. Quantified marker values are assumed to follow a multivariate normal distribution but not necessarily with equal variances for two populations. Other options include Box-Cox variable transformations, QQ-plots, interactive graphics associated with changes in sensitivity and specificity as a function of the cut-off. We provide an example to illustrate the usefulness of data transformation and of how linear combination of markers can significantly improve discriminative power. This finding highlights potential difficulties with methods that reject individual markers based on univariate analyses.

Biomarkers, Tumor↗

PubMed2001

[A comparison of serum Cyfra 21-1 and SCC AG in the diagnosis of squamous cell esophageal carcinoma].

Cyfra 21-1 is a useful marker in lung cancer. The only tumor marker used at the present time in oesophageal squamous cell carcinoma (OSCC) is SCC (squamous cell carcinoma). In this study we evaluated the pre-treatment sensitivity and specificity of these two markers in this setting. Cyfra 21-1 and SCC were determined by radio-immunoassay on 76 patients having OSCC. Staging was done according to the UICC 1978 classification based on endoscopy, baryum enema and CT scan. The sensitivity of Cyfra 21-1 is better at the 1.5 ng/ml level (54%) than at the usual reported level of 3.6 ng/ml (26%). The best level for sensitivity of SCC is 1.5 ng/ml. At these levels, sensitivity of Cyfra 21-1 and SCC for advanced stages (T3 or M1) are respectively 72% and 50%. The specificity of Cyfra 21-1 and SCC for stages T1 or T2 are respectively 53% and 73%. The combination of these two markers increase sensitivity at 64% for all stages and at 89% for advanced stages (T3 or M1) and is a significant prognostic factor for survival. This study confirms the value of Cyfra 21-1 in OSCC at the normal level of 1.5 ng/ml. The combination with SC improves the results. We now need to evaluate the role of these two markers in the follow up of oesophageal carcinoma.

Aged↗

PubMed2000

Methodological issues associated with tumor marker development. Biostatistical aspects.

The search for markers as potential prognostic factors for different stages of disease is becoming a major task in clinical research. Enormous amounts of information on the effectiveness of tumor markers are being published, and many of these results are conflicting and thus adding confusion to the area. In this paper we discuss the problem of multiplicity that we believe is one of the major statistical reasons for the conflicting results. We further review the ROC curve and the area under it as a popular statistical tool for evaluating the ability of a marker to distinguish between two populations. Finally we provide an extension to the ROC analysis when several markers are available.

Journal Article↗

PubMed2000

Relating genotype and phenotype in breast cancer: an analysis of the prognostic significance of amplification at eight different genes or loci and of p53 mutations.

Breast cancer heterogeneity can be related directly to its variability at the genetic level. Thus, tumor genotyping could be a valuable approach to define breast tumor subtypes. It has been shown that it is possible to delineate subgroups of breast tumors according to specific sets of DNA amplifications. The aim of the present work was to study the prognostic significance of these DNA amplifications. We studied DNA amplification at eight genes or loci (AIB1, CCND1, EMS1, ERBB2, FGFR1, MDM2, MYC, and RMC20C001) as well as p53 mutations in a series of 640 breast cancer patients who had not received presurgical therapy and analyzed the correlations with survival DNA amplification was assessed by Southern blotting and was scored positive when exceeding three to five copies. Mutations in the p53 gene were searched by four-color fluorescent single. strand conformational polymorphism, using an automated sequencer. Of the nine genetic alterations tested, four (CCND1, EMS1, FGFR1, and p53 mutations) showed a significant association with reduced disease-free (DFS) and/or overall survival (OVS) in the unselected set of patients by univariate test. Correlations for p53 were found only when selecting mutations in exons 5 or 7. Analysis of node-negative and -positive subgroups of patients showed that MDM2 amplification and p53 mutations bore prognostic significance in node-negative patients, whereas amplification of CCND1, EMS1, and FGFR1 correlated with poor outcome in node-positive patients. Multivariate analysis on an unselected set of patients retained significance for the amplification of EMS1, FGFR1, and MDM2 with DFS, of CCND1 with OVS, and of RMC20C001 with both DFS and OVS. Interestingly, stratified analysis according to nodal status confirmed results obtained in the univariate tests: significance of MDM2 amplification and p53 mutations in node-negative and that of CCND1, EMS1, and FGFR1 in node-positive patients. We also observed an association between the number of genetic alterations observed in a tumor and poor prognosis. Patients with two or more amplified loci had a worsened outcome. Strongly correlating coamplifications such as CCND1 and FGFR1, as well as ERBB2 and MYC, were associated with a significant reduction of patient survival, thus indicating cooperative effects. Our data support the idea that genetic alterations in breast cancer are not only helpful for phenotyping purposes, but can also represent powerful prognostic indicators in the clinical practice.

Breast Neoplasms↗

PubMed2000

Pro-gastrin-releasing peptide, neuron specific enolase and chromogranin A as serum markers of small cell lung cancer.

BACKGROUND: Small cell lung cancer (SCLC) yields neuroendocrine properties. Pro-gastrin-releasing peptide (ProGRP), neuron specific enolase (NSE) and chromogranin A (CGA) are therefore putative serum markers in this disease. AIM: To assess any difference in the sensitivity-specificity relationship between these neuroendocrine markers regarding various control populations and disease extent. METHOD: A total of 146 patients were prospectively assessed clinically and biologically. Serum marker titrations were performed using commercial immunoradiometric assays (NSE, CGA) or ELISA (ProGRP). Areas under receiver operating characteristic curves (AUC-ROC) were calculated in order to assess the sensitivity-specificity relationship of each marker and to compare marker accuracy. Maximum Youden indices were used to determine marker thresholds able to produce the best overall diagnostic information. RESULTS: Assessing the sensitivity in the SCLC population and the specificity in benign lung disease, ProGRP demonstrated the best sensitivity relationship in as much as its AUC-ROC was significantly greater than the ones calculated using NSE and CGA (respective values, 0.95, 0.89, 0.70; two-tailed Z-test <0.05). The ProGRP threshold value, which offered the best sensitivity-specificity relationship was 53 pg/ml corresponding to a 0.80 sensitivity and a 0.96 specificity. In addition, when specificity was assessed in NSCLC and again the sensitivity in the whole SCLC population, ProGRP continued to demonstrate a greater AUC-ROC in comparison with other markers. Using the 53 pg/ml threshold the specificity of this marker was excellent with no false positives in NSCLC. On the other hand, none of the markers were able to discriminate limited from extensive SCLC as suggested by the fact that AUC-ROC, constructed when sensitivity was defined as a positive test in extensive disease and specificity as a true negative test in limited disease, did not reach the upper left octant (AUC 0.65, 0.71 and 0.63 for ProGRP, NSE and CGA, respectively). CONCLUSION: ProGRP yields the best sensitivity-specificity feature in SCLC, a result deserving further studies designed to evaluate the clinical applicability of this marker.

Adult↗

PubMed2000

Immunocytochemical assessment of sigma-1 receptor and human sterol isomerase in breast cancer and their relationship with a series of prognostic factors.

The purpose of this study was to immunocytochemically investigate two new markers, the sigma-1 receptor and the human sterol isomerase (hSI), in comparison with a series of clinicopathological and immunocytochemical prognostic factors in a trial including 95 patients with operable primary breast cancers. Our results showed no statistically significant relationship between these two markers and the age of the patients, their menopausal status, the tumour size and its histological grade, the nodal status and the expression of the Ki-67 proliferative marker. However, we evidenced a close correlation between the sigma-1 receptor expression and the hormonal receptor positivity (P = 0.008), essentially due to a link with the progesterone receptor status (P = 0.01). By contrast there was an inverse relationship between hSI expression and the oestrogen receptor and/or progesterone receptor positivity (P = 0.098). A significant relationship was shown between both the sigma-1 receptor, hSI expressions and Bcl2 expression, with P= 0.017 and 0.035 respectively. We also assessed whether the expression of the sigma-1 receptor or hSI might be linked with disease-free survival (DFS) and found that the presence of hSI and the absence of sigma-1 receptor expression were associated with a poorer disease-free survival (P= 0.007). Altogether these results suggest that in primary breast carcinomas in association with the evaluation of the steroid receptor status, the sigma-1 receptor and hSI may be interesting new markers useful to identify those patients who might be able to benefit from an adjuvant therapy.

Adult↗

PubMed2000

Clinical significance and prognostic value of CA72-4 compared with CEA and CA19-9 in patients with gastric cancer.

Carcinoembryonic antigen (CEA) and CA 19-9 are both widely used in the follow up of patients with gastrointestinal cancer. More recently another tumor marker, named CA 72-4 has been identified and characterized using two different monoclonal antibodies B72.3 and CC49. Several reports evaluated CA 72-4 as a serum tumor marker for gastric cancer and compared its clinical utility with that of CEA or CA 19-9; few reports concerned its prognostic value. In the present study, CA 72-4 is evaluated and compared with CEA and CA 19-9 in various populations of patients with gastric cancer and benign disease; for 52 patients with gastric adenocarcinoma and 57 patients without neoplastic disease CEA, CA 19-9 and CA 72-4 were evaluated before treatment. Sensitivity of the tumor markers CA 72-4, CA 19-9 and CEA at the recommended cut-off level in all 52 patients were 58%, 50% the sensitivity increased to 75%. of these markers, for non metastatic patients, multivariate analyses indicated that none of the markers were significant, when adjusted for gender and age (which were indicators of poor prognosis); patients with abnormal values of CA72-4 tended to have shorter survival than patients with normal values (p<0.07). In the metastatic population, only high values of CA19-9 (p<0.02) and gender (women) p<0.03) were indicators of poor prognosis in univariate analysis; multivariate analysis revealed that both CA72-4 (p=0.034) and CA19-9 p=0.009), adjusted for gender were independent prognostic factors. However, CA72-4 lost significance (p=0.41) when adjusted for CA19-9 and gender, indicating that CA19-9 provides more prognostic information than CA72-4. When limited to the metastatic male population with normal values of CA 19-9 and CEA, CA 72-4 pretherapeutic positive levels were associated with a worse prognosis (p<0.005). In conclusion, this study suggests that the addition of CA 72-4 to CEA and/or CA 19-9 could improve sensitivity in gastric cancer. The prognostic role of this marker is not yet clearly demonstrated but its usefulness in the monitoring of gastric cancer should be taken into account.

Adenocarcinoma↗

PubMed1999

Continual reassessment methods in phase I trials of the combination of two drugs in oncology.

Most phase I trials in oncology use standard methods for treating successive groups of patients with increasing doses in order to determine the maximum tolerated dose (MTD). These methods have been criticized because they treat many patients at suboptimal dose levels, and do not provide an accurate estimation of the best dose level. Continual reassessment methods for the study of toxicity in single agent phase I trials have recently been advocated since they present many advantages over traditional methods. Although the advantages of these methods are recognized by most clinical investigators, their use is not widespread and their advantages have not yet been universally accepted. A maximum likelihood continual reassessment method was conducted retrospectively and compared to the originally planned standard method in a two drug combination phase I trial in order to study its applicability in this setting. Calculations from the binomial distributions and simulations were used for identifying the MTD, for the proportion of patients treated at the MTD or at one dose level just below, and for the proportion of patients treated at doses above the MTD. If the new method had been applied in this study, the MTD would have been reached much earlier, since, most of the time, higher dose levels were recommended. This result shows the feasibility of the new method in a two-drug setting and its use should be encouraged since fewer patients are treated at suboptimal dose levels or at dose levels above the MTD.

Antineoplastic Agents, Phytogenic↗