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Biomedical subjects

S Benhamou

Publications and source records attributed to S Benhamou.

At least 73 records · Page 4Linked to original sources
PubMed1995

Local relapse and contralateral tumor rates in patients with breast cancer treated with conservative surgery and radiotherapy (Institut Gustave Roussy 1970-1982). IGR Breast Cancer Group.

BACKGROUND: Breast conservation is now established treatment for patients with small breast cancers. The authors reviewed a large series of patients with long term follow-up who underwent conservative treatment. Clinical and pathologic factors were analyzed to identify patients at an increased risk of relapse in the breast (local relapse) or development of a contralateral tumor. METHODS: Seven hundred fifty-seven patients with unilateral invasive breast cancer (T0-2, N0-1, M0) were treated conservatively (wide local excision and radiotherapy) at the Institut Gustave-Roussy between 1970 and 1982. The median follow-up was 9 years. The risk of local relapse or development of a contralateral tumor (as first event) was studied by univariate analysis for the main clinical, pathologic, and treatment factors. Those found to be significant were entered into a Cox proportional regression analysis. RESULTS: Fifty-one patients relapsed in the treated breast (actuarial local relapse rates at 5 and 10 years were 5% and 8%, respectively) and 34 in the contralateral breast (actuarial contralateral tumor rates at 5 and 10 years were 3% and 6%, respectively). Multivariate analysis of the risk factors for local relapse showed that only age younger than 40 years (P < 0.02) or inadequate surgical excisioin (P < 0.02) were significant. No particular risk factors for contralateral tumor development were identified. CONCLUSIONS: Overall, for most patients, the risk of local relapse or of developing a contralateral tumor was low. A small number of young patients with inadequately excised tumors are at higher risk of local relapse, need more meticulous surgery, and may merit higher dose radiotherapy.

Actuarial Analysis↗
PubMed1995

Characteristics of UV-induced mutation spectra in human XP-D/ERCC2 gene-mutated xeroderma pigmentosum and trichothiodystrophy cells.

To study the relationships between mutagenesis and carcinogenesis, we compared the mutations and their frequency induced by ultraviolet irradiation at 254 nm (UV-C) in XP-D (GM-08207B/XP6BE), TTD/XP-D (TTD1VI-LAS-KMT11) and wild-type (MRC-5V1) human cells. XP-D and TTD/XP-D cells, mutated in the same XP-D/ERCC2 gene, are deficient in nucleotide excision repair. Whereas XP-D patients develop early skin tumors, TTD patients do not exhibit abnormal levels of cancers. After verification of UV hypersensitivity and DNA repair defect of the immortalized cell lines XP-D and TTD compared with a wild-type cell line, UV-induced mutagenesis was studied with a new shuttle vector pR2, carrying the target lacZ' gene. The UV-mutation frequencies in XP-D and TTD cells were similar and significantly increased compared with normal cells. Sequence analysis of 312 independent mutant plasmids revealed that more rearrangements were induced in TTD cells (16%) than in XP-D (5%) and normal cells (1%), while XP-D cells exhibited a twofold higher rate of tandem mutations compared with TTD and normal cells. In the three cell lines, a predominance of G:C to A:T transitions was found, especially in chiefly on the cytosine at 5'-TC-3' sites. The types of UV-induced point mutations in TTD cells were, however, more similar to those in normal cells than those found in XP-D cells. XP-D mutations were preferentially located in 5'-TCPur-3' sites, while mutations in normal and TTD cells were mostly at 5'-TCC-3' sites. Analysis of mutation spectra revealed differences in the location of the mutational hotspots between the three lines. Although the mutation frequency of the UV-irradiated pR2 vector is much higher in TTD and XP-D cells than in normal cells, the mutation spectrum is closer between TTD and normal cells as compared with XP-D cells. These dissimilarities could contribute to an explanation of some of the differences between the two syndromes.

Amino Acid Sequence↗
PubMed1995

Prophylactic cranial irradiation for patients with small-cell lung cancer in complete remission.

BACKGROUND: Prophylactic cranial irradiation in patients with small-cell lung cancer decreases the overall rate of brain metastases without an effect on overall survival. It has been suggested that this treatment may increase neuropsychological syndromes and brain abnormalities indicated by computed tomography scans. However, other retrospective data suggested a beneficial effect on overall survival for patients in complete remission. PURPOSE: Our purpose was to evaluate the effects of prophylactic cranial irradiation on brain metastasis, overall survival, and late-occurring toxic effects in patients with small-cell lung cancer in complete remission. METHODS: We conducted a prospective study of 300 patients who had small-cell lung cancer that was in complete remission. The patients were randomly assigned to receive either prophylactic cranial irradiation delivering 24 Gy in eight fractions during 12 days (treatment group) or no prophylactic cranial irradiation (control group). A neuropsychological examination and a computed tomography scan of the brain were performed at the time of random assignment and repeatedly assessed at 6, 18, 30, and 48 months. Patterns of failure were analyzed according to total event rates and also according to an isolated first site of relapse, using a competing-risk approach. RESULTS: Two hundred ninety-four patients who did not have brain metastases at the time of random assignment were analyzed. The 2-year cumulative rate of brain metastasis as an isolated first site of relapse was 45% in the control group and 19% in the treatment group (P < 10(-6)). The total 2-year rate of brain metastasis was 67% and 40%, respectively (relative risk = 0.35; P < 10(-13)). The 2-year overall survival rate was 21.5% in the control group and 29% in the treatment group (relative risk = 0.83; P = .14). There were no significant differences between the two groups in terms of neuropsychological function or abnormalities indicated by computed tomography brain scans. CONCLUSIONS: Prophylactic cranial irradiation given to patients with small-cell lung cancer in complete remission decreases the risk of brain metastasis threefold without a significant increase in complications. A possible beneficial effect on overall survival should be tested with a higher statistical power. IMPLICATIONS: The results of the trial favor, at present, the indication of prophylactic cranial irradiation for patients who are in complete remission. A longer follow-up and confirmatory trials are needed to fully assess late-occurring toxic effects. The possible effect on overall survival needs to be evaluated with a larger number of patients in complete remission, and a meta-analysis of similar trials is recommended.

Aged↗
PubMed1995

[Susceptibility to bronchial cancer: an example of genetic-environmental interaction].

Tobacco is responsible for 80 to 90% lung cancer cases in industrialized countries. However, genetic factors are likely to be involved in lung cancer susceptibility. Some degree of familial aggregation of lung cancer is evidenced in most family studies. On the other hand, many tobacco carcinogens are metabolised by enzymes of the P450 cytochrome family. Two enzymes of cytochrome P450, CYP1A1 and CYP1A2, are inducible by tobacco carcinogens, and animal studies evidenced a genetic polymorphism of CYP1A1 associated with tumour occurrence after administration of a polycyclic aromatic hydrocarbon. In humans, an association between lung cancer and some P450 polymorphisms (CYP1A1, CYP2D6, CYP2E1) was suggested but the results of epidemiologic studies are discordant and difficult to interpret. In addition, there is a polymorphism of glutathione S-transferase isoenzyme (GSTM1) involved in carcinogen elimination; an association between this polymorphism and lung cancer has also been reported. Further studies on combined effects of these polymorphisms should allow an identification of sub-groups of individuals at high risk of lung cancer.

Aged↗
PubMed1994

Differential effects of tar content, type of tobacco and use of a filter on lung cancer risk in male cigarette smokers.

BACKGROUND: To date, the effect of tar exposure, the use of a filter and the type of tobacco (light or dark) on the risk of lung cancer have not been studied together. METHODS: Data from a case-control study on lung cancer were used to evaluate the specific effects of these three parameters. Cases of lung cancer and controls were interviewed in hospitals in France from 1976 to 1980. The past tar content of cigarettes distributed by the French Tobacco Monopoly was obtained. The results presented concern an exclusively male population of lifelong smokers of French cigarettes and lifelong smokers of light imported cigarettes. The population comprised 1114 cases of histologically confirmed lung cancer and 1466 hospitalized controls. RESULTS: An increase in risk was found among smokers of both dark and light cigarettes (relative risk [RR] = 2.6, 95% confidence interval [CI]:1.1-6.5) and among lifelong smokers of dark cigarettes (RR = 1.7, 95% Cl: 0.9-3.2) compared to lifelong smokers of light cigarettes. Similarly, the risk of lung cancer was higher among smokers of both non-filter and filter cigarettes (RR = 1.6, 95% Cl: 0.9-2.7) and among lifelong smokers of non-filter cigarettes (RR = 1.6, 95% Cl: 0.9-2.8) than among lifelong smokers of filter cigarettes. A borderline significant increase in risk was observed for smokers of French cigarettes compared to smokers of light imported cigarettes (RR = 2.6, 95% Cl: 0.9-7.7). No significant difference in the risk of lung cancer was observed among smokers of French cigarettes according to the proportion of years of smoking high tar cigarettes. CONCLUSION: This study tends to demonstrate a separate effect of type of tobacco, use of a filter and tar content in addition to the usual characteristics of cigarette smoking on lung cancer risk.

Case-Control Studies↗
PubMed1994

Occupational risk factors for renal cell carcinoma: a case-control study.

A case-control study of 196 histologically proved cases of renal cell carcinoma and 347 controls matched for age at interview, sex, hospital, and interviewer was conducted in France between 1987 and 1991. A complete occupational history was recorded for each patient and occupations were coded blindly according to the International Standard Classification of Occupations. In women, none of the risks were significant. Among men, after adjustment for the educational level, cigarette smoking, and Quetelet index before diagnosis, significantly increased matched odds ratios (ORs) were found for sales workers (OR = 2.1, 95% confidence interval (95% CI) 1.2-4.0), managers (OR = 3.3, 95% CI 1.2-8.9), and textile workers and tailors (OR = 6.2, 95% CI 1.1-33.7). For this last occupational group, an increase in risk was found with an increased duration of exposure.

Carcinoma, Renal Cell↗
PubMed1993

Risk factors for renal-cell carcinoma in a French case-control study.

A hospital-based case-control study of renal-cell carcinoma was conducted in France from 1987 to 1991. A total of 196 histologically confirmed cases (138 males and 58 females) and 347 controls (235 males and 112 females), matched for sex, age at interview, hospital and interviewer, were included. The risk of renal-cell carcinoma was not apparently increased with number of cigarettes per day, duration of smoking or early age at first cigarette smoking in males. No significant trend was found in the risks with increasing Quetelet index (QI) at the age of 20 in males. On the contrary, the risks increased significantly with an increasing QI prior to diagnosis. In females, the trends in risks were significant both for the relative weight at the age of 20 and prior to diagnosis. The consumption of regular or decaffeinated coffee, tea or alcoholic beverages was not associated with renal-cell carcinoma, in males or in females.

Adult↗
PubMed1993

[Cancers related to tobacco smoking].

Tobacco smoking is the major cause of lung cancer. Cigarette smokers have a risk of lung cancer 10 to 15 times greater than nonsmokers. Tobacco and alcohol are the main risk factors for cancers of oral cavity, larynx, pharynx and oesophagus (cancers of the upper respiratory and upper digestive tract) and the effects of tobacco and alcohol are multiplicative. For these cancers, the risk associated with tobacco was about 2 to 4 among people who drink little or no alcohol. Risks of lung cancer and of cancers of the upper respiratory and upper digestive tract increase with an increasing number of cigarettes smoked per day and duration of smoking. Tobacco is also a risk factor for bladder cancer. Cigarette smoking is a possible contributory factor in the development of kidney, pancreatic and cervical cancers. Among males, lung cancer mortality increased regularly over time and today, lung cancer is the leading cause of death and illness from cancer. Substantial reductions in the number of deaths from tobacco-related cancers could be achieved if a large proportion of smokers stopped smoking.

Adult↗
PubMed1993

Long-term effects on the thyroid of irradiation for skin angiomas in childhood.

Thyroid morphological and functional tests were carried out on 396 patients who were recalled because their thyroid gland had been exposed during hemangioma irradiation in childhood 11-43 years before (median, 22 years). The irradiations have been classified into two categories based on their duration: short duration, from a few seconds to a few minutes (90S and X rays), and long duration, from 30 min to several hours (336Ra, 192Ir, and 32P). The risk of a thyroid nodule increased significantly with the total dose received by the thyroid; it was linked to the dose delivered in the short duration (excess relative risk per Gy = 10), but not to that delivered in the long duration. The risk of a simple diffuse goiter, which also increased with the dose received by the thyroid, did not depend on the duration of the irradiation. In conclusion, this study emphasizes the role of the dose rate in the risk of thyroid nodule, the detection of which does not appear to be improved by plasma thyroid marker determination.

Child↗
PubMed1992

A randomised 2 x 2 factorial design to evaluate different smoking cessation methods.

A study with a 2 x 2 factorial design was performed to evaluate the effectiveness of acupuncture, of nicotine gum and the effect of the association on smoking cessation. After a one-year follow-up period, the success rates were in the same order of magnitude for nicotine gum (active treatment: 10%, placebo: 8%) group and for acupuncture (active treatment: 8%, placebo: 10%) group.

Acupuncture Therapy↗
PubMed1992

[Influence of the distribution of the dose on carcinogenic effects of ionizing radiations of low lineal energy transfer on the thyroid tissue].

The frequency of thyroid nodules has been studied among 396 children irradiated for a hemangioma, from 1946 to 1973. 226Ra, 192Ir, 90Y, 32P, 90Sr, as well as X-rays had been used for treatments. The doses of radiation received by the thyroid of each child have been estimated retrospectively. The irradiations have been classified in two categories based on their duration: less than 30 min., and more than 30 min. The doses received with each of these two types of irradiation were summed for each patient. The risk of thyroid nodule increased as a function of the dose to thyroid only for the dose delivered with the short duration. This study emphases the importance of the role of the dose rate in the risk of radio-induced tumour.

Adolescent↗
PubMed1991

Long-term effects in skin and thyroid after radiotherapy for skin angiomas: a French retrospective cohort study.

To evaluate the long-term effects of skin angioma irradiation, a recall programme was established which included the systematic recalculation of the radiation dose to the skin and the thyroid. 22% of the 6229 patients contacted had a dermatological examination which revealed cutaneous dystrophy in 81% of the 1137 exposed angiomas and in 39% of the 208 unexposed angiomas. The risk of dystrophy (telangiectasia, hypopigmentation, superficial and subcutaneous atrophy) was 12.1 higher (P less than 0.0001) among patients who had received a surface skin dose above 30 Gy than among those who had received a dose of 10 Gy or less. The relative risk for each dystrophy component increased significantly (P less than 0.001) with surface skin dose. Furthermore, 14 basal cell carcinomas (BCC) were observed in 12 patients from the exposed group for all quantities of radiation, with a mean latency period of 22 years. No BCC was observed for a surface skin dose below 10 Gy. Thyroid testing was done on a subgroup of 431 patients whose thyroid gland had been particularly exposed during angioma irradiation. After recalculation, the dose delivered to the gland was below 1 Gy in 98% of patients. Only 13 thyroid nodules were discovered (1 hot and 12 cold). 1 patient with a cold nodule had a malignant thyroid tumour 21 years after irradiation. He belonged to the group of 7 patients who had received a thyroid dose above 1 Gy. Although no morphological abnormality was found in 98% of the tested patients, most (92%) had a thyroid iodine content below 15 mg (the standard French value), while a raised serum thyroglobulin level (greater than 30 ng/ml) was observed in 17%. This might confer a higher risk of subsequently developing thyroid nodules.

Adolescent↗
PubMed1989

Changes in patterns of cigarette smoking and lung cancer risk: results of a case-control study.

Data from a case-control study on lung cancer were used to evaluate how changes in cigarette habits, mainly smoking cessation, switch from non-filter to filter brands, from dark to light tobacco, or from handrolled to manufactured cigarettes, and reduction in daily consumption influence lung cancer risk. The results presented concern all males, exclusive cigarette smokers, involved in the study, i.e. 1,057 histologically confirmed lung cancer and 1,503 matched controls. The general decrease in lung cancer risk with the years since cessation was also found in each subgroup of cigarette exposure defined by duration of smoking, daily consumption and type of cigarettes smoked. Among smokers who had given up smoking from less than 10 years earlier, the lung cancer risks were two-fold higher for those who had stopped smoking for coughing or health reasons than for those who had stopped smoking for reasons other than health problems. A decrease in lung cancer risk, although not significant, was found in people who switched from non-filter brands to filter brands and from dark to light tobacco and in smokers who reduced their daily consumption of cigarettes by more than 25% as compared to smokers who had not changed habits.

Carcinoma↗
PubMed1988

Sister chromatid exchanges and chromosomal aberrations in lymphocytes of nurses handling cytostatic agents.

A cohort study of 29 nurses who constantly handled cytostatic drugs, and 29 controls matched according to sex and age, was carried out between 1983 and 1986. Cytogenetic damage was assessed by sister chromatid exchanges (SCE) and chromosomal aberrations. No significant increase in mean number of SCE was found for nurses (7.37) as compared to matched controls (7.00), whereas a significant excess of SCE (p less than 0.001) was observed for smokers (8.23) as compared to non-smokers (6.75). The number of SCE was studied in relation to the amount and nature of cytostatics handled as well as to the duration of exposure. A significant association (p less than 0.05) was found between individual mean number of SCE and the total number of drugs handled after adjustment for confounding factors. In contrast, the number of SCE was not significantly related to the nature of drugs handled or to the duration of exposure. With regard to chromosomal damage, no significant difference was observed between nurses and controls in gap, break, dicentric and translocation frequencies.

Antineoplastic Agents↗
PubMed1988

Cosmetic results following lumpectomy, axillary dissection and radiotherapy for small breast cancers.

Between 1970 and April 1982, 592 women with T(1), small T2, N0, N1, M0 breast cancer were managed by lumpectomy, axillary dissection and radiotherapy at the Institut Gustave-Roussy (IGR). The overall cosmetic result and the degree of asymmetry, fibrosis and telangiectasia of the treated breast were assessed by the radiation oncologist at each follow-up visit. The changes in these cosmetic parameters with time are shown. At 5 years the overall cosmetic result was excellent in 59%, good in 38% and fair or poor in 8%. A multivariate analysis was performed of the factors associated with a cosmetic defect. The most significant factors were tumour size, the presence of defect after surgery and the daily applied dose per fraction to the breast. Surgical and radiotherapy technique (especially alternate day fractionation) can significantly affect the cosmetic result obtained.

Axilla↗
PubMed1988

Occupational risk factors of lung cancer in a French case-control study.

A case-control study of 1625 histologically confirmed cases of lung cancer and 3091 controls matched for sex, age, hospital admission, and interviewer was conducted in France between 1976 and 1980. The results presented concern the effects of different occupations on the occurrence of lung cancer among 1334 male cases and 2409 matched controls. Occupations were coded blindly according to the International Standard Classification of Occupations. An excess risk of lung cancer was observed for the following occupations after adjustment for cigarette exposure: farmers (RR = 1.24, p less than 0.06), miners and quarrymen (RR = 2.14, p less than 0.02), plumbers and pipe fitters (RR = 1.80, p less than 0.04), motor vehicle drivers (RR = 1.42, p less than 0.01).

Agricultural Workers' Diseases↗