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P Van Houtte

Publications and source records attributed to P Van Houtte.

At least 19 recordsLinked to original sources
PubMed1995

Computer-assisted morphonuclear characterization of radiotherapy-induced effects in MXT mouse mammary adenocarcinomas surviving earlier radiotherapy.

PURPOSE: To present the effects of different radiotherapeutic treatments on the morphonuclear characteristics and growth of the MXT mouse mammary adenocarcinoma. METHODS AND MATERIALS: We collected MXT tumor cells by means of fine-needle aspirations during various radiotherapeutic treatments and analyzed the morphological aspects of the cell nuclei by means of the digital cell image analysis of Feulgen-stained nuclei. In addition, we studied the morphonuclear aspects of cells from MXT tumors that had been radioresistant cell enriched. These radioresistant cell-enriched tumors involved MXT tumors that had survived one or two previous radiotherapies. The radiotherapy-induced effects on the morphonuclear characteristics were monitored by means of both monovariate (one-way variance) and multivariate (principal components and step-wise linear discriminant) analyses. RESULTS: The monovariate analyses showed that radiotherapy significantly influenced the values of the parameters relating to nuclear size (nuclear area--NA), the frequency of small dense chromatin clumps (short run length emphasis--SRL) in the nuclei, and the overall chromatin condensation level (local mean--LM). The global effect corresponded to a decrease in the overall chromatin condensation level in the radioresistant cell-enriched MXT tumors. This decrease occurred concomitantly with an increase in the frequency of the small dense chromatin clumps in the nuclei and a decrease in the nuclear area. The multivariate analyses showed that it was possible to quantitate the proportion of "radiosensitive-like" and "radioresistant-like" cell nuclei in the various MXT tumor types under study. CONCLUSIONS: The development of certain morphonuclear parameters, that is, the NA, the SRL, and the LM, could be proposed to predict the response of human tumors to radiotherapy as, indeed, could the quantitation of the proportion of radioresistant cells.

Adenocarcinoma↗
PubMed1994

Toxicity of combined radiation and chemotherapy in non-small cell lung cancer.

The present paper reviews the different acute and late effects due to radiation and chemotherapy on the different organs lying within the chest (lung, esophagus, spinal cord, heart and skin) using available experimental and clinical data. Some specific issues are stressed, such as the problem of time interval between drug and radiation, the latency period for late effects, and the necessity to use an actuarial method to evaluate the real risk of late effects.

Actuarial Analysis↗
PubMed1994

International survey of radiotherapy practice for radical treatment of non-small cell lung cancer.

This postal survey was designed to assess the possible agreement or differences in staging, selection criteria and radiation volumes for a curative treatment of non-small cell lung cancer. The questionnaire was sent to 263 radiotherapists from 38 different countries; 114 responses (43%) were received. In this sample, some geographical differences, mainly for staging procedures (the use of brain CT scan or bone scan) and selection criteria (the role of positive mediastinal lymph nodes), were seen. There was a good agreement between radiotherapists in the choice of treatment volumes in the five different clinical scenarios. The clinical and radiobiological findings of the last decade have discredited the routine use of split course or hypofractionation schedules. Further studies are needed to improve the technical basis of thoracic radiotherapy.

Carcinoma, Non-Small-Cell Lung↗
PubMed1994

[Non small-cell bronchial cancers: toxicity of the association radiotherapy-chemotherapy. Review of the literature].

Radiation therapy is the elective treatment of inoperable non small cell lung cancer, but is potentially curative only for a few of them: failures result from distant metastases and/or from progressive local disease. During the last years, following the progress in chemotherapy, combining radiation and drugs is becoming a more common approach. Nevertheless, one of the main concerns remains the potential interference between both modalities leading to an increased toxicity, which may outweigh all potential benefit. Several organs can be a target for acute or late toxicity: lung (pneumonitis and fibrosis), esophagus (acute esophagitis, stenosis), heart (pericarditis, impaired ventricular functions, heart failure, coronary stenosis), spinal cord (transient myelopathy, radiation myelitis), skin (moist desquamation, fibrosis, telangiectasia). The current published trials combining drug and radiation appear to be a rather safe approach especially when avoiding concomitant treatment. However, several points remain unsolved: the optimal combination scheme, the real risk of late damage observation including the second cancer occurrence risk. This risk is uneasy to evaluate due to the long latency period. The way of describing the late damage is crucial, seeking for a more precise system of evaluating, recording and reporting late effects, taking into account objective damage as well as the patient's symptoms. Therefore, combining drug and radiation should preferentially be performed within prospective studies, with precise evaluation procedures.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1993

Postoperative radiotherapy after pneumonectomy: impact of modern treatment facilities.

PURPOSE: The present study was undertaken to see how modern treatment facilities, computed tomography (CT)-based treatment planning and linear accelerator, have modified the results of postoperative irradiation after a pneumonectomy for lung cancer. METHODS AND MATERIALS: Between 1970-1985, 103 patients were treated in our department after a pneumonectomy: 50 patients with a T1T2N0 tumor and 53 patients with a T3, N1 or N2 tumor. Three groups were considered: 27 patients had only surgical resection, 51 patients were irradiated postoperatively with a Co60 source, and 25 patients were treated using those modern facilities. RESULTS: The 5-year survival varies from 4% to 31% according to the tumor extent but also to the radiation technique. Patients treated with a Co60 source had a dismal 5-year survival rate (8%) whereas patients treated with the modern facilities had a 5-year survival rate of 30% similar to the 31% of the control surgical group including less advanced tumors. CONCLUSION: Linear accelerator and computed tomography-based treatment planning improved the accuracy of postoperative thoracic irradiation and allow to deliver high doses to the mediastinum even after a pneumonectomy.

Combined Modality Therapy↗
PubMed1993

In vitro characterization of radiotherapy-induced morphonuclear modifications on chemosensitive as opposed to chemoresistant neoplastic cells.

PURPOSE: We describe by means of digital cell image analysis the influence of X-ray radiation on three in vitro cultured cell lines for which we set up chemosensitive and chemoresistant variants. METHODS AND MATERIALS: The three cell lines correspond to the MXT mouse mammary and the T24 and J82 neoplastic human bladder cells. The digital cell image analysis was carried out by computing morphometric (nuclear size), densitometric (proportion of cells in the G2 cell cycle phase), and textural features (chromatin pattern characteristics) on Feulgen-stained nuclei. RESULTS: The results show that such digital cell image analyses make it possible to monitor radiotherapy-induced effects on these morphonuclear characteristics accurately. X-ray radiotherapy induces a dose-dependent increase in the proportion of cells in the G2 phase of the cell cycle along with a decrease in the overall chromatin condensation level. These two concomitant phenomena lead to a marked radiotherapy-induced increase in nuclear size. We also observed that radiotherapy-induced effects at the morphonuclear level are not only highly specific to the cell type analyzed, that is MXT mouse mammary or J82 or T24 human bladder carcinoma cells, but also to the fact that the cells are either chemosensitive or chemoresistant. CONCLUSION: The digital cell image analyses of Feulgen-stained nuclei is helpful in monitoring the irradiation-induced morphonuclear modifications.

Animals↗
PubMed1993

[Adjuvant treatments in resectable cancer of the rectum: preoperative radiotherapy, postoperative radiation- and chemotherapy or nothing?].

In addition to curative surgical resection, which remains the treatment of choice in rectal cancer, are there any other effective adjuvant treatments capable of increasing the life expectancy of patients by decreasing the frequency of local recurrences and distant metastases? Analysis of the results and clinical arguments in favour of adjuvant treatments demonstrates the efficacy of preoperative radiotherapy which decreases the pelvic recurrence rate in patients with T2T3T4NxM0 tumours. Postoperative administration of a combination of radiotherapy and chemotherapy (5-FU, methyl CCNU) also improved the survival rate and disease-free interval in patients operated for rectal cancer. However, the adverse effects and toxicity of this adjuvant treatment limit its routine administration. Lastly, the efficacy of postoperative radiotherapy and postoperative chemotherapy, administered separately, has not been clearly demonstrated to date.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1993

Ovarian dysgerminoma: a therapeutic challenge.

Dysgerminoma remains a rare but quite interesting tumor. Over the last 40 years, the prognosis has markedly improved with a 5 year survival increasing from around 30% to more than 80%. Precise diagnosis and adequate staging are mandatory to define the best treatment approach aiming to cure the woman, while preserving her quality of life (ovarian function and fertility).

Adolescent↗
PubMed1993

Testis tumors.

Explore the source record for details and available documents.

Adolescent↗
PubMed1993

Postoperative irradiation for thyroid cancer.

The place of external irradiation for thyroid cancers remains controversial. Between 1974 and 1989, 94 patients with a differentiated thyroid cancer were seen in our department for additional treatment (radioiodine with or without external radiation) after a surgical resection. 56 patients were treated with radioiodine alone and 38 patients had an additional course of external radiation. Survival was identical for the two groups but the local relapse rates were 21% and 3% respectively. So, in this retrospective study, the addition of external radiation appears to improve the local control especially in the case of an incomplete surgical resection or extracapsular tumor extension. This benefit was achieved without severe radiation-induced late effects.

Adolescent↗
PubMed1992

Monitoring of radiotherapy-induced morphonuclear modifications in the MXT mouse mammary carcinoma by means of digital cell image analysis.

The present work deals with the characterization of the morphological changes induced by ionizing radiation on MXT mouse mammary cancer cell nuclei. The monitoring of the radiotherapy-induced morphonuclear modifications was carried out by means of digital cell image analysis, which made it possible to compute morphometric (nuclear area), densitometric (nuclear DNA content) and textural (chromatin pattern characteristics) parameters assessed on Feulgen-stained nuclei. The biological material was obtained from serial fine needle-aspirations performed on control tumors and 2Gy and 8Gy irradiated tumors. Digital cell image analyses were assessed at the 7th, 18th, and 28th days-post irradiation. We showed that radiotherapy induced specific morphonuclear modifications that appeared in a dose-dependent and time-dependent manner. The 2Gy and 8Gy radiotherapy doses led to an increase in the mean nuclear area value, this feature being observed at both the 1st and the 4th week post-irradiation. The resultant effect on the chromatin pattern characteristics corresponded to a decrease in overall condensation level as compared to the control cell nuclei. Finally, the mean nuclear DNA content increased at the 1st week post-irradiation, but decreased at the 4th week post-irradiation as compared to the MXT control tumor. Computerized cell image analysis, therefore, appears to be a useful tool in helping to monitor the radiotherapy-induced effects that occur in neoplastic cell nuclei and which can be observed by means of optical microscopy.

Animals↗
PubMed1992

[Postoperative irradiation in pulmonary cancer?].

Postoperative radiation remains a controversial issue in the management of lung cancer. Despite a better local control, a major concern is always the possible late lung effects induced by high doses of radiation required to achieve this benefit. In our works, we have been able to show that with an adequate technique and the use of CT-scan for treatment planning, such high doses can safely be delivered. Furthermore, several prognostic factors were identified including the degree of mediastinal lymph node involvement.

Combined Modality Therapy↗
PubMed1992

[Breast-preserving treatment of breast cancer and peroperative curietherapy].

From May 1988 to December 1990, 35 patients benefitted from a breast-conserving treatment (tumor resection with at least 1 cm of free margin, axillary dissection and peroperative brachytherapy). The iridium sources were introduced 24 h later, delivering between 15 to 17.5 Gy. Three weeks later an additional course of external radiation delivered a dose of 50 Gy in 5 weeks to the whole breast. In this series, only very early breast lesions were included and no patient received additional chemotherapy. Due to the short period of observation, we only report on the acute side effects even if until now we have not seen any case of tumor relapse. We did not observe any major complications after this combined approach: only three patients developed a local infection requiring antibiotics. Esthetic evaluation is quite encouraging with all women showing good and excellent results from the physician's and patient's points of view. This approach seems to be quite interesting cosmetically as it allows to correct the breast shape while preserving an adequate position of the implant and so preserving a good oncological approach.

Adult↗
PubMed1991

Radiotherapy in squamous cell esophageal cancer.

As the classical surgical treatment of squamous cell esophageal carcinoma is associated with poor 5-year survival rates and high operative mortality, radiotherapy and chemotherapy are being used as adjuvant or alternative primary treatments. The authors present their view on several therapeutic approaches and describe their irradiation technique.

Carcinoma, Squamous Cell↗
PubMed1990

Psychosocial correlates of oestrogen and progesterone receptors in breast cancer.

Psychosocial correlates of hormone receptor status in primary breast cancers were investigated in 93 consecutive patients. Life event, coping style, and psychological adjustment self-report scales were completed. The 75 patients with receptor-positive (oestrogen and/or progesterone) tumours were better adjusted psychologically than the 18 patients with receptor-negative lesions. These findings may explain the relations that have been found between psychosocial variables and survival.

Adaptation, Psychological↗
PubMed1990

Breast conserving treatment for early cancers. Rationales, perspectives and techniques.

The paper reviews the rationale for breast conserving treatment for early cancers; the different studies are presented as well as the technical limitations and problems involved by surgery and radiotherapy. Nowadays, breast conserving treatment includes a limited resection of the tumor followed by a course of radiation. This treatment allows to preserve the breast and spares a mutilation to the woman. It requires an early diagnosis of the disease, stressing the need for a well-designed screening program.

Antineoplastic Combined Chemotherapy Protocols↗