Biomedical subjects

D Pontvert

Publications and source records attributed to D Pontvert.

34 records · Page 2Linked to original sources

PubMed1990

Impact of cervical disease and its definitive radiotherapeutic management on survival: experience in 2013 patients with squamous cell carcinomas of the oropharynx and pharyngolarynx.

Two thousand thirteen patients with squamous cell carcinoma of oropharynx and pharyngolarynx were reviewed with regard to neck disease presentation and disease-free survival after radical radiotherapy. All patients were staged according to both the AJCC 1976 and the UICC 1978 classifications. Causes of failure, disease-free survival, and complication rates were assessed. Sixty percent had a clinically positive neck. The 3-year disease-free survival rates were 58%, 44%, 38%, and 25% for AJCC N0, N1, N2, and N3 cases, respectively. Corresponding UICC figures were 58%, 46%, 26%, and 29%. Analyzed parameters were nodal stage, size, site and fixity, and location of primary. Complications attributed to neck disease did not exceed 3%. A critical appraisal of the nodal staging systems is derived from these sets of data.

Carcinoma, Squamous Cell↗

PubMed1989

Conventional megavoltage radiotherapy in the management of malignant epithelial tumours of the parotid gland.

This is an evaluation of definitive conventional megavoltage radiotherapy in a consecutive series of 35 patients presenting malignant epithelial tumours of the parotid gland. In this series, the 5-year actuarial locoregional control rate was 41% with a 5-year crude survival rate of 36%. The results are analyzed according to tumour presentation and tumour doses. Six of 15 patients with tumours larger than 6 cm have had a lasting locoregional control. During the same period 43 other patients received radiotherapy as a post-operative modality. Results obtained in this group confirm the previously published data. While recent studies tend to demonstrate the specific efficacy of high LET radiation in the management of locally advanced salivary gland tumours, radical conventional radiotherapy can still be employed with a curative intent when neutron facilities are not available.

Adult↗

PubMed1989

A multivariate primary tumour control analysis in 465 patients treated by radical radiotherapy for cancer of the tonsillar region: clinical and treatment parameters as prognostic factors.

Out of a consecutive series of 698 cases of squamous cell carcinomas of the tonsillar region treated by radical megavoltage radiotherapy, a determinate group of 465 cases remained eligible for a multivariate analysis of the pretreatment features of the disease and treatment-related parameters predictive of lasting control of the disease at the primary site. T-stage and initial site within the tonsillar region, were the significant pretreatment factors. Tumours arising from the glossopalatine sulcus which are characterized by involvement of the tongue, do significantly worse than those arising from other sites within the tonsillar region: i.e. the tonsil itself, posterior pillar and to a lesser extent the anterior pillar. As regards treatment-related parameters in the 465 cases which received tumour doses of at least 55 Gy, only the length of overall treatment time was found to be predictive. Combining both pretreatment and treatment variables, T-stage (p less than 0.0001), overall treatment time (p less than 0.0001) were by decreasing order of significance the predicting factors, followed by initial site (p = 0.006). When present, tumour extension to the anatomical structures anterior to the tonsillar region was also found to be significant (p = 0.05). Based on these factors, a multivariate model was constructed and tested by estimating the product-limit survival of the various categories of patients. Four groups are individualized with 3 years local control rates ranging from 90 to 21%. The predictive accuracy of the model was assessed by log-rank test significance levels. The model may help to select patients for whom conventional radical radiotherapy is inadequate, and combined modality or altered fractionation regimes should be tried particularly for advanced tumours of the glossopalatine sulcus, and any case with significant invasion of the oral cavity.

Carcinoma, Squamous Cell↗

PubMed1989

Induction chemotherapy in advanced head and neck cancer. Preliminary results of a randomized study.

From March 1983 to June 1986, 100 patients with locally advanced squamous cell carcinoma of the head and neck were randomized to receive either two courses of chemotherapy prior to local therapy (group A), or local therapy alone (group B). Local treatment consisted of primary radiotherapy in all patients. When a poor response was observed after 55 Gy, surgery was performed. The chemotherapy regimen was a combination of cisplatinum, bleomycin, vindesine, and mitomycin C. The response rate to induction chemotherapy (group A) was 50% for the primary tumor (CR: 10% and PR: 40%). At the end of radiotherapy, the overall tumor response rates in the two groups A and B, were 77% and 79% respectively. Complete disappearance of the primary tumor occurred more often than that of the lymph node metastases. The response rate to induction chemotherapy for lymph node metastases was 27.1% (CR: 9% and PR: 18.1%). An initial major response to chemotherapy predicted subsequent efficacy of irradiation on 90% of the cases, while a failure of chemotherapy had no predictive value in this respect. The survival rates in groups A and B were 66.5% vs. 65.1% at 1 year and 35% vs. 46.2% at 2 years. Local disease-free and disease-free intervals were similar in both groups. A Cox's multi-step regression analysis revealed two significant independant prognostic factors: size of primary tumor and nodal status. After adjustment for these factors, the chemotherapy did not seem to improve the effectiveness of the local treatment in terms of loco-regional control and survival.

Adult↗

PubMed1988

Results of irradiation in squamous cell carcinoma of the soft palate and uvula.

Out of a series of 235 patients presenting with tumours of the soft palate at the Institut Curie, between 1958 and 1980, 146 cases were analysed to evaluate the results of radical radiation therapy. Seventy patients (48%) had advanced T3-T4 disease and 40 patients (27%) had clinically involved metastatic nodes. All patients had a minimum follow-up of 5 years. In 103 cases, megavoltage X-ray therapy was employed. For 43 patients, presenting with small or moderately advanced tumours, a combination of megavoltage and intra-oral orthovoltage X-rays was used. The local control rate at 3 years was 92% for T1, 70% for T2, 58% for T3 and 49% for T4 lesions. Nodal failure was seen in 19 patients. In 9 of these, it was not associated with failure at the primary site, 7 out of 9 occurring marginally or outside the treatment portals. Complications were observed in 16 patients, 7 requiring surgery. The crude 3 and 5 year survival rate was 52 and 40%, respectively, and the disease-free survival 59 and 53%.

Carcinoma, Squamous Cell↗

PubMed1988

Primary radiotherapy of squamous cell carcinoma of the oropharynx and pharyngolarynx: tentative multivariate modelling system to predict the radiocurability of neck nodes.

In a series of 1251 cases of squamous cell carcinomas of oropharynx and pharyngolarynx with clinically positive neck and treated primarily by radiation therapy a determinate group of 798 cases remained eligible for a multivariate analysis of the prognostic factors related to the regional outcome. Node size (p less than 0.0001), node fixity (p = 0.016) and T stage (p = 0.02) were the significant pretreatment factors independently predictive of neck node control. when regarding the treatment modalities in this determinate group of patients who received tumor doses of at least 55 Gy, only the treatment duration was found to be predictive (p = 0.002). Based on these factors, a multivariate model was constructed and tested by estimating the product-limit survival of the various groups of patients. The predictive accuracy of the equation was assessed by the log-rank test significance levels. The model may help to select, in many clinical situations, the appropriate approach of the management of metastatic neck disease, either by definitive radiation therapy or by combined modalities.

Analysis of Variance↗

PubMed1987

Impact of neck node radioresponsiveness on the regional control probability in patients with oropharynx and pharyngolarynx cancers managed by definitive radiotherapy.

We reviewed a series of 1,666 patients with squamous cell carcinoma of the oropharynx and pharyngolarynx treated with definitive radiation therapy to determine whether or not radioresponsiveness of the metastatic neck nodes is a reliable indicator of their radiocurability. In a determined group of 708 patients with clinically positive neck nodes, only one third of the adenopathies (247/759) completely regressed at the completion of the treatment. At 6 months, only ten percent of the nodes remained palpable. Lymph node clearance rates and halving diameter times were tumor size-dependent. Node clearance rate was also influenced by the site of the primary lesion. The impact of various parameters, both intrinsic and extrinsic to the tumor behavior, is discussed. Neck control probability was significantly higher for complete responders. In this group, the ultimate node control was as good for adenopathies larger than 6 cm as for the smaller ones. Tumor control probability directly related to clearance rate following radiotherapy. Finally, therapeutic implications are derived for nodal dose adjustments and optimal applicability of radiosurgical combinations.

Carcinoma, Squamous Cell↗

PubMed1987

[Carcinomas of the nasopharynx in adults].

From 1959 through 1980, 139 MO adult patients (greater than 15 Y.) presenting with nasopharyngeal cancer were treated by definitive radiotherapy: 103 (74%) undifferentiated carcinomas and 36 (26%) squamous cell carcinomas. Chemotherapy was prescribed only in case of failure of treatment. Case distribution is the following according to UICC classification: stages I and II: 12%, stage III: 16%, stage IV: 72%. Survival rate is respectively 70%, 45%, 20%. The overall 3 and 5 year survival rate is 46% and 30%. Almost 80% of the failures occur by the end of the second year. Local control is 95% for T1-T2, 73% for T3 and around 50% for T4 cases. Isolated node failure occurs in 2% and distant metastases in 30%.

Adolescent↗

PubMed1986

[Radiologic surveillance of irradiated glomal tumors].

A favorable clinical result was obtained in 10 patients with jugular glomal tumors treated by external radiotherapy (approximately 50 Gy), alone or combined with surgical treatment, and preceded in some cases by embolization. Radiologic review examinations showed complete stability of lesions without bone reconstruction phenomena, in spite of a decrease in tympanic mass and regression of functional symptoms.

Adult↗

PubMed1986

[Treatment of epitheliomas of the parotid. Apropos of 93 cases treated at the Curie Institute].

From 1955 through 1982, a series of 93 cases of parotid gland carcinoma were treated at the Institut Curie: 55 primarily and 28 for recurrent tumors. Treatment modalities included surgery alone (n : 14), surgery followed by radiotherapy (n : 43), and radiotherapy alone (n : 36). The most advanced cases were mostly in the latter group. With a mean follow-up of 13 years, the actuarial loco-regional control is 67% (62/93) and the median survival 10 years. Ultimate loco-regional control was achieved in 86% of cases managed by surgery alone, 88% of cases managed by surgery and radiotherapy and 33% of cases managed by radiotherapy. In the latter group, control rate was 42% (8/19) in those primarily treated by radiotherapy. Prognosis was related to histology. Twenty patients (22%) presented distant metastasis. The potential advantages of neutron irradiation for parotid neoplasms is discussed.

Adolescent↗

PubMed1985

[Glomus jugulare tumors. Possibilities of radiotherapy].

From 1964 to 1981, twelve patients with glomus jugulare tumors involving bony lesions of base of skull were treated by high energy radiation. Ten patients presented cranial nerve pairs paralysis. Conventionally fractionated doses of 45 to 60 Gy were applied, and 11 of the 12 patients were alive and clinically stable after follow up for between 3 and 20 years. One patient died of an intercurrent infection after 16 years. Strict irradiation technique is essential to avoid principally neurologic complications. Favorable results after radiotherapy were obtained in extensive tympano-jugular forms.

Adult↗

PubMedDate not supplied

[Conformal radiotherapy: principles and classification].

'Conformal radiotherapy' is the name fixed by usage and given to a new form of radiotherapy resulting from the technological improvements observed during, the last ten years. While this terminology is now widely used, no precise definition can be found in the literature. Conformal radiotherapy refers to an approach in which the dose distribution is more closely 'conformed' or adapted to the actual shape of the target volume. However, the achievement of a consensus on a more specific definition is hampered by various difficulties, namely in characterizing the degree of 'conformality'. We have therefore suggested a classification scheme be established on the basis of the tools and the procedures actually used for all steps of the process, i.e., from prescription to treatment completion. Our classification consists of four levels: schematically, at level 0, there is no conformation (rectangular fields); at level 1, a simple conformation takes place, on the basis of conventional 2D imaging; at level 2, a 3D reconstruction of the structures is used for a more accurate conformation; and level 3 includes research and advanced dynamic techniques. We have used our personal experience, contacts with colleagues and data from the literature to analyze all the steps of the planning process, and to define the tools and procedures relevant to a given level. The corresponding tables have been discussed and approved at the European level within the Dynarad concerted action. It is proposed that the term 'conformal radiotherapy' be restricted to procedures where all steps are at least at level 2.

Accreditation↗

PubMedDate not supplied

[Conformal radiotherapy of prostatic cancer: a general review].

Recent progress in radiotherapeutic management of localized prostate cancer is reviewed. Clinical aspects--including dose-effect beyond 70 Gy, relative role of conformal radiation therapy techniques and of early hormonal treatment--are discussed as well as technical components--including patient immobilization, organ motion, prostate contouring, beam arrangement, 3-D treatment planning and portal imaging. The local control and biological relapse-free survival rates appear to be improved by high dose conformal radiotherapy from 20 to 30% for patients with intermediate and high risk of relapse. A benefit of overall survival is expected but not yet demonstrated. Late reactions, especially the rectal toxicity, remain moderate despite the dose escalation. However, conformal radiotherapy demands a high precision at all steps of the procedure.

Antineoplastic Agents, Hormonal↗

PubMedDate not supplied

[Radiotherapy using a combination of photons and protons for locally aggressive intracranial tumors. Preliminary results of protocol CPO 94-C1].

PURPOSE: From October 1993 through July 1998, 48 assessable adult patients with non-resectable aggressive intracranial tumors were treated by a combination of high dose photon + proton therapy at the Centre de Protonthérapie d'Orsay. PATIENTS AND METHODS: Grade 1 and 4 gliomas were excluded. Patients benefited from a 3D dose calculation based on high-definition CT and MRI, a stereotactic positioning using implanted fiducial markers and a thermoplastic mask. Mean tumor dose ranged between 63 and 67 Gy delivered in five weekly sessions of 1.8 Gy in most patients, according to the histological types (doses in Co Gy Equivalent, with a mean proton-RBE of 1.1). RESULTS: With a median 18-month follow-up (range: four-58 months), local control in tumors located in the envelopes and in the skull base was 97% (33/34), and in parenchymal tumors, 43% (6/14) only. Two patients (5%) presented with a clinically severe radiation-induced necrosis (temporal lobe and chiasm). CONCLUSION: In our experience, high-dose radiation combining photons and protons is a safe and highly efficient procedure in selected malignancies of the skull base and envelopes.

Adult↗

PubMedDate not supplied

[3D automatic expansion: clinical application].

The determination of the various volumes (GTV: gross target volume, CTV: clinical target volume, PTV: planned target volume) recommended by the ICRU 50 report is a critical step in conformal treatment planning, since treatment optimisation procedures and documentation rely on accurate dose-volume histograms. The shape and the size of the CTV vary with the computer algorithm, the patient image acquisition parameters, the definition of the GTV and the margins surrounding it. The automatic expansion programs included in commercially available treatment planning system require careful validation and control before and during their routine use by the clinicians. Significant differences have been observed between 2D- and 3D-based expansions, with a usual underestimation of the PTV by 2D algorithms.

Algorithms↗

PubMedDate not supplied

[Radiotherapy of stage T1-T2 M0 prostatic adenocarcinoma. Analysis of the carcinologic results of a multicenter study of 610 patients. Groupe Radiothérapie de la Commission de Coopération Médicale Intercentres (CCMI)].

PURPOSE: Retrospective analysis of the results of radiotherapy in localized prostatic adenocarcinoma. Complications were excluded. PATIENTS AND METHODS: Six-hundred-and-ten T1-T2 adenocarcinomas of the prostate were treated with continuous courses of external beam radiation therapy in 19 participating Institutes between January 1983 and January 1988. The mean follow-up was 10.4 years; the mean age of patients at the beginning of radiotherapy was 68.5 years. RESULTS: A 10-year, local control had been achieved in 86% of T1-T2 (81.4% for T2). The 5- and 10-year metastatic relapse rates were 25.3% and 30% (29% and 38.1% for T2), respectively. At 10 years, 62.4% of T1-T2 were recurrence-free; overall survival rate was 45.8% and cause-specific survival rate was 70.5%; 29.9% of T1-T2 patients were alive and disease-free. T category (TNM), pathologic grade, pelvic lymph node status, local tumor control, and obstructive ureteral symptoms were correlated with survival. The influence of pelvic nodes radiation, dose, overall treatment time, previous endocrine treatment, and transuretral resection was not significant for disease-free survival (alive and disease-free) and other endpoints. CONCLUSION: There was no difference between the French series (1975-1982 and 1983-1988). The results of the literature are comparable to ours. As far as prognostic factors are concerned, this report provides evidence that the explainable variables which influence survival depend on the tumor and patient status.

Adenocarcinoma↗