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T Conroy

Publications and source records attributed to T Conroy.

67 records · Page 4Linked to original sources

[Immediate hematological toxicity during combination chemotherapy-radiotherapy of Hodgkin's disease].

The hematologic immediate toxicity during radiotherapy for Hodgkin's disease was studied from a series of 72 patients with stage IIB or III who received 3 courses or more of chemotherapy before radiotherapy. The toxicity in the group of 36 of them who received total nodal irradiation (TNI) was the most important. Sixteen of the 28 TNI had irradiation interrupted, 12 of them began with inverted Y type. The blood cells count at the beginning of the treatment was crucial; only 16% of the patients had interruption of irradiation when the blood cells count was normal; on the other side, 63% had interruption when the blood cells count was abnormal (P less than 0.05). Toxicity was due to the daily destruction of the dividing bone marrow stem cells located in the irradiated area, from the first day of treatment; there was a progressive decrease in the pool of these stem cells within a late resaturation. The absence of resaturation of this pool after initial chemotherapy and after the first part of irradiation explained the immediate and durable toxicity; in the same way, inverted Y irradiation destroyed a great part of active bone marrow (40%) and the pool of remaining stem cells with high mitotic index would be located in areas irradiated subsequently. So, waiting for the absolute normalisation of blood cells count before beginning irradiation and start irradiation by mantle field (rather than inverted Y) seem to be the 2 measures able to reduce the number of interruptions of irradiation due to hematotoxicity.

Adolescent↗

[Natural history and development of bone metastasis. Apropos of 429 cases].

The records of 429 patients seen at the Centre Alexis-Vautrin in 1979 and 1980 with bony metastases were retrospectively reviewed to assess their natural history and survival. Breast was the location of primary lesion in 140 patients (32.6%), lung in 95 patients (22.1%) and prostate in 33 patients (7.7%). The primary tumor was of unknown origin in 42 cases (10.9%). The median survival from time of diagnosis was 5 months. Two and 5-year survival rates were 17.5 and 5.1% respectively. According to the nature of the primary tumor, 2 and 5-year survival periods for bony metastases were 36.4 and 7.9% in breast cancer, 33.3 and 15.2% in prostatic cancer, 4.3 and 2.1% in metastases of unknown origin, 2.1 and 0% in pulmonary carcinoma. Multivariate analysis revealed four factors to be of prognostic significance for survival: the nature of the primary tumor, the absence of local relapse, the disease-free interval and the absence of metastases in other sites. Patients with hormone-sensitive lesions or slowly-growing tumors had a better prognosis.

Adolescent↗

[Pseudolinitis plastica of breast origin].

The most common type of gastric metastases secondary to carcinoma of the breast is the one showing a linitis plastica appearance. The roentgenologic aspect when performing an upper gastrointestinal examination with barium contrast is typical and allows the differential diagnosis with the primitive linitis. The linitis plastica type of metastatic breast carcinoma results from transmural infiltration of the stomach wall with initial deposit of tumor cells in the submucosal or subserosal regions. CT provide valuable information concerning the metastatic spread.

Adenocarcinoma, Scirrhous↗

[Acquired hypogammaglobulinemia and malabsorption with villous atrophy sensitive to a gluten-free diet].

The observation of a 21 year-old man with primary common variable hypogammaglobulinemia and total villous atrophy is reported. Gluten withdrawal induced considerable improvement in malabsorption and mucosal damage. However, protein-losing enteropathy, nodular lymphoid hyperplasia and immunoglobulin deficiency were persistent. To our knowledge, improvement on gluten-free diet has been reported until now in 18 previous cases. This report illustrates the links between immunodeficiency and malabsorption, which are discussed.

Adult↗

The spatial distribution of fixed mutations within genes coding for proteins.

We have examined the extensive amino acid sequence data now available for five protein families - the alpha crystallin A chain, myoglobin, alpha and beta hemoglobin, and the cytochromes c - with the goal of estimating the true spatial distribution of base substitutions within genes that code for proteins. In every case the commonly used Poisson density failed to even approximate the experimental pattern of base substitution. For the 87 species of beta hemoglobin examined, for example, the probability that the observed results were from a Poisson process was the minuscule 10(-44). Analogous results were obtained for the other functional families. All the data were reasonably, but not perfectly, described by the negative binomial density. In particular, most of the data were described by one of the very simple limiting forms of this density, the geometric density. The implications of this for evolutionary inference are discussed. It is evident that most estimates of total base substitutions between genes are badly in need of revision.

Amino Acid Sequence↗

The estimation of genetic divergence.

We have independently repeated the computer simulations on which Nei and Tateno (1978) base their criticism of REH theory and have extended the analysis to include mRNAs as well as proteins. The simulation data confirm the correctness of the REH method. The high average value of the fixation intensity mu 2 found by Nei and Tateno is due to two factors: 1) they reported only the five replications in which mu 2 was high, excluding the forty-five replications containing the more representative data; and 2) the lack of information, inherent to protein sequence data, about fixed mutations at the third nucleotide position within codons, as the values are lower when the estimate is made from the mRNAs that code for the proteins. REH values calculated from protein or nucleic acid data on the basis of the equiprobability of genetic events underestimate, not overestimate, the total fixed mutations. In REH theory the experimental data determine the estimate T2 of the time average number of codons that have been free to fix mutations during a given period of divergence. In the method of Nei and Tateno it is assumed, despite evidence to the contrary, that every amino acid position may fix a mutation. Under the latter assumption, the measure X2 of genetic divergence suggested by Nei and Tateno is not tenable: values of X2 for a alpha hemoglobin divergences are less than the minimum number of fixed substitutions known to have occurred. Within the context of REH theory, a paradox, first posed by Zuckerkandl, with respect to the high rate of covarion turnover and the nature of general function sites in proteins is resolved.

Amino Acids↗

Evaluation of clinical efficacy of new medical treatments in advanced colorectal cancer. Results of a workshop organized by the EORTC GITCCG. European Organization for Research and Treatment of Cancer. Gastrointestinal Tract Cancer Cooperative Group.

During the last few years several factors have contributed to an increasing change in the medical treatment of advanced colorectal cancer. Among them are the more general acceptance of the impact of chemotherapy on quality of life and survival in first as well as in second-line treatment, the introduction of new drugs and the definition of novel endpoints which can roughly be defined as "patient benefit". For this reason the European Organization for Research and Treatment of Cancer (EORTC) Gastrointestinal Tract Cancer Cooperative Group (GITCCG) felt it was appropriate to organize a workshop with experts from different countries and national groups to discuss in depth several aspects concerning the treatment of patients with advanced colorectal cancer.

Clinical Trials as Topic↗

Clinical randomized study of 5FU monitoring versus standard dose in patients with head and neck cancer: preliminary results.

Prospective studies of dose adaptation of continuous 5FU infusion combined with cisplatin have shown that pharmacologically guided dosing was feasible in the treatment of head and neck carcinomas. Adaptative dosing results in reduced haematological toxicity, but few data are available for clinical response rate. Preliminary results (38 patients) of a randomized trial comparing standard dose of 5FU (20 patients) and monitoring of 5FU based on pharmacokinetic information (half-cycle area under the curve, 18 patients) indicate that haematological tolerance and complete response rate were improved. Severe (GIII-GIV) thrombocytopenia and neutropenia were significantly reduced during cycle 2 (0% versus 11.1% and 5.5% versus 27.7% respectively, p < 0.01) and cycle 3 (0% versus 27.7% and 6.6% versus 33.3% respectively, p < 0.001). The complete response rate was increased in the group with monitoring of 5FU doses (55.5% versus 40.0%, p < 0.001). These interesting results will be confirmed at the end of the trial, which is expected to include 126 patients.

Adult↗