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R Valdagni

Publications and source records attributed to R Valdagni.

At least 19 recordsLinked to original sources
PubMed2004

Fitting late rectal bleeding data using different NTCP models: results from an Italian multi-centric study (AIROPROS0101).

BACKGROUND AND PURPOSE: Recent investigations demonstrated a significant correlation between rectal dose-volume patterns and late rectal toxicity. The reduction of the DVH to a value expressing the probability of complication would be suitable. To fit different normal tissue complication probability (NTCP) models to clinical outcome on late rectal bleeding after external beam radiotherapy (RT) for prostate cancer. PATIENTS AND METHODS: Rectal dose-volume histograms of the rectum (DVH) and clinical records of 547 prostate cancer patients (pts) pooled from five institutions previously collected and analyzed were considered. All patients were treated in supine position with 3 or 4-field techniques: 123 patients received an ICRU dose between 64 and 70 Gy, 255 patients between 70 and 74 Gy and 169 patients between 74 and 79.2 Gy; 457/547 patients were treated with conformal RT and 203/547 underwent radical prostatectomy before RT. Minimum follow-up was 18 months. Patients were considered as bleeders if showing grade 2/3 late bleeding (slightly modified RTOG/EORTC scoring system) within 18 months after the end of RT. Four NTCP models were considered: (a) the Lyman model with DVH reduced to the equivalent uniform dose (LEUD, coincident with the classical Lyman-Kutcher-Burman, LKB, model), (b) logistic with DVH reduced to EUD (LOGEUD), (c) Poisson coupled to EUD reduction scheme and (d) relative seriality (RS). The parameters for the different models were fit to the patient data using a maximum likelihood analysis. The 68% confidence intervals (CI) of each parameter were also derived. RESULTS: Forty six out of five hundred and forty seven patients experienced grade 2/3 late bleeding: 38/46 developed rectal bleeding within 18 months and were then considered as bleeders The risk of rectal bleeding can be well calculated with a 'smooth' function of EUD (with a seriality parameter n equal to 0.23 (CI 0.05), best fit result). Using LEUD the relationship between EUD and NTCP can be described with a TD50 of 81.9 Gy (CI 1.8 Gy) and a steepness parameter m of 0.19 (CI 0.01); when using LOGEUD, TD50 is 82.2 Gy and k is 7.85. Best fit parameters for RS are s=0.49, gamma=1.69, TD50=83.1 Gy. Qualitative as well as quantitative comparisons (chi-squared statistics, P=0.005) show that the models fit the observed complication rates very well. The results found in the overall population were substantially confirmed in the subgroup of radically treated patients (LEUD: n=0.24 m=0.14 TD50=75.8 Gy). If considering just the grade 3 bleeders (n=9) the best fit is found in correspondence of a n-value around 0.06, suggesting that for severe bleeding the rectum is more serial. CONCLUSIONS: Different NTCP models fit quite accurately the considered clinical data. The results are consistent with a rectum 'less serial' than previously reported investigations when considering grade 2 bleeding while a more serial behaviour was found for severe bleeding. EUD may be considered as a robust and simple parameter correlated with the risk of late rectal bleeding.

Combined Modality Therapy↗
PubMed1999

Patterns of radiotherapy for early breast cancer in Northern Italy compared with European and national standards.

PURPOSE: To assess the current practice of early breast cancer (EBC) post-operative irradiation in Northern Italy and to evaluate its conformance with European standards and recently defined national guidelines. MATERIALS AND METHODS: Fifty Radiotherapy departments in Northern Italy received a questionnaire assessing parameters on pre-treatment evaluation of patients, on preparation, prescription and execution phases of irradiation (XRT), on surgery-XRT-chemotherapy integration and on follow-up. The analysis of collected information was compared with both the 1991 EORTC-EUSOMA guidelines and the 1997 AIRO (Italian Association for Radiation Oncology) minimal requirements on EBC post-operative irradiation. RESULTS: Thirty-nine out of 50 (78%) departments answered the questionnaire. All treat T1-T2 tumours, after tumourectomy or, mostly, quadrantectomy. The mean interval between surgery and XRT is 45 +/- 14 days. Chemotherapy is delivered concurrently in 70% of departments, CTV is represented by residual mammary gland in 100% of cases, while 38% and 52% of departments occasionally treat internal mammary and axillary or supra-clavicular nodes, respectively. Total dose delivered to the whole breast is 46-50 Gy in 98% (1.8-2 Gy/fraction). The tumour bed is boosted in 79% of cases. An immobilization device is used in 28% of cases CTV is clinically localized in 62% of patients. Tangential fields are simulated in 85% of centres, with film storage in 78% of cases. Co-60 units are used in 58% and/or 4-6 MV X-rays in 70% of centres, mostly utilizing beam modifiers. Computerized treatment planning is performed in 95% of cases. Fifty-five percent of departments prescribe the dose at the ICRU point. Portal films are routinely taken in 50% of cases. Boost irradiation is mainly performed using external XRT. Lastly, acute and late side effects and cosmesis are respectively evaluated in 100%, 98% and 90% of centres. CONCLUSIONS: Results on current practice in Northern Italy generally show a good conformance with European standards. However, some variables related to treatment prescription, simulation and treatment planning need to be standardized. This set of information was largely utilized by the AIRO to define national guidelines adapted to the Italian resources and situation.

Breast Neoplasms↗
PubMed1997

Hyperfractionated radiation in combination with local hyperthermia in the treatment of advanced squamous cell carcinoma of the head and neck: a phase I-II study.

Twenty-seven patients with cervical metastases from squamous cell head and neck tumours were treated with hyperfractionated XRT (total dose 69.60-76.80 Gy, 1.2 Gy b.i.d. five times a week) combined with a total of two to six sessions of superficial external HT. Acute local toxicity was mild; as major acute side effects, only one ulceration was recorded. No severe late side effects were observed. Late toxicity was similar to that observed in our previous studies with the combination of heat and radiation. Nodal complete response was observed in 77% of patients, partial response was observed in 15% of patients and no change was observed in 8% of patients. Five-year actuarial nodal control was 64.5 +/- 19% and 5-year actuarial survival was 24 +/- 10%. The treatment of nodal metastases from head and neck tumours with the combination of HT and hyperfractionated XRT is feasible with an acceptable acute and late toxicity profile.

Adult↗
PubMed1997

Clinical target volume localization using conventional methods (anatomy and palpation) and ultrasonography in early breast cancer post-operative external irradiation.

PURPOSE: To evaluate the accuracy of three methods, anatomy (A), palpation (P) and ultrasounds (US) in localizing the clinical target volume (CTV) in patients (pts) with early breast cancer (EBC) undergoing breast external irradiation as part of conservation therapy. MATERIAL AND METHODS: One hundred consecutive pts with EBC (T(is) 1%, T1 78%, T2 21%, N- 68%, N+ 32%), treated with conservation surgery and breast irradiation with opposed tangential portals, were prospectively analyzed. Anatomically, palpatory or ultrasound defined field borders for CTV localizations were determined in the same position thanks to the utilization of a vacuum-formed cellulose acetate immobilization cast, removed during CTV definitions. RESULTS: P and US CTV localizations have been found to coincide on the four margins (superior, inferior, medial, lateral) in only 1/100 pts, while no pt showed identical A and US CTV localizations. Only 31/397 (8%) field measurements with A, and 98/395 (25%) with P corresponded to US border definition. If mean and median values of each field border were considered, the CTV was generally overestimated with P appearing more accurate than A in a gross definition of the target (P < 0.01). However, a geographical miss of at least one field border of CTV occurred in 55% of pts with A and in 36% of pts with P. The most critical margin to be defined with conventional methods was the superior one: an underestimation of the cranial border of CTV with A was observed in 51% and with P in 22% of pts (22% and 8%, respectively, when an underestimation by more than 1.5 cm was considered). When pre-menopausal and peri/post-menopausal groups of pts were separately analyzed, conventional methods were highly inaccurate to define the superior border in younger pts, in which a geographical miss was noted with A in 62% and with P in 35% of cases (P < 0.05). When an underestimation of more than 1.5 cm was evaluated, these values were reduced to 33% and 12%, respectively (P = 0.02). Also, in the subgroup of pre-menopausal patients the CTV defined by palpatory reference lines appeared to be more accurate than A-method (P < 0.01). CONCLUSIONS: Conventional methods frequently appear inadequate to localize residual mammary gland in EBC post-operative external irradiation. This analysis evidentiates the inaccuracy of empirical CTV definition, and suggests that palpation or anatomical reference borders should be critically used and that state of art imaging methods should be included in treatment planning, particularly in pre-menopausal pts. If economical or individual variables have to be taken into account, palpation might be considered in post-menopausal women.

Adult↗
PubMed1997

Ten-year results of treatment of ductal carcinoma in situ (DCIS) of the breast with conservative surgery and radiotherapy.

The optimal treatment of ductal carcinoma in situ (DCIS) of the breast has not yet been established. The effectiveness of adjuvant postoperative radiotherapy after conservative surgery is debated. Few data are available in Italy on the combined treatment. A collaborative multi-institutional study on this issue in 10 radiation oncology departments of the north-east of Italy was conducted. One hundred and thirty nine women with DCIS of the breast were treated between 1980 and 1990. Age ranged between 28 and 88 years (median 50 years). Surgical procedures were: quadrantectomy in 108, lumpectomy in 22 and wide excision in 9 cases. The axilla was surgically staged in 97 cases: all the patients were node-negative. Radiation therapy was delivered with 60Co units (78%) or 6 MV linear accelerators (22%) for a median total dose to the entire breast of 50 Gy (mean 49.48 Gy; range 45-60 Gy). The tumour bed was boosted in 109 cases (78%) at a dose of 4-30 Gy (median 10 Gy) for a minimum tumour dose of 58 Gy. Median follow-up was 81 months. Thirteen local recurrences were recorded, 7 intraductal and 6 invasive. All recurrent patients had a salvage mastectomy and are alive and free of disease. Actuarial overall, cause-specific and recurrence-free survival at 10 years are of 93%, 100% and 86%, respectively. The results of this retrospective multicentric study substantiate the favourable data reported in the literature and confirm the efficacy of the breast-conserving treatment of DCIS employing conservative surgery and adjuvant radiation therapy.

Adult↗
PubMed1996

[Hyperthermia and palliative radiotherapy for sarcoma].

The current treatment of bone and soft tissue sarcomas consists of a multimodality approach based on the combination of surgery, radiotherapy and, more rarely, chemotherapy. Since local recurrence is an important cause of failure and morbidity, new treatment modalities such as hyperthermia, have been proposed to try to overcome this problem. July, 1982, to June, 1993, twelve patients (15 lesions) with recurrent or locally advanced sarcoma, were treated at the Department of Radiation Oncology, S. Chiara Hospital-Trento (Italy) with irradiation and hyperthermia. Radiation therapy was delivered with different techniques using palliative or radical doses (24-70 Gy) and different fractionation schedules. Local microwave hyperthermia was given in 2-9 sessions (mean 4.7). Eight (53.3%) complete responses and 4 (26.6%) partial responses were observed. Three lesions recurred at 11, 13, and 30 months; 5-year actuarial local control was 25.4 +/- 13.4%. Actuarial 5-year overall survival was 49.5 +/- 16.4%. Toxicity was mild: two superficial necroses, spontaneously healed after few months, were observed; local pain during hyperthermic treatment was recorded in 15% of sessions. Lesion volume and total radiation dose appeared to be correlated with the response. In our experience, the combination of radiotherapy and hyperthermia seems to be a valuable therapeutic approach in the treatment of locally advanced or recurrent sarcomas.

Actuarial Analysis↗
PubMed1996

[Clinical and methodological aspects of quality assurance in external radiotherapy: optimization of radiotherapy in early cancer of the breast].

Since 1988, a specific physical and clinical quality assurance program for external whole breast irradiation has been activated in our department. Three areas of clinical investigation and related audit loops are analyzed to show our policy to improve the quality of patient care. Quality control procedures deal with (a) the evaluation of the adequacy of conventional methods of clinical target volume (CTV) localization, (b) the evaluation of the adequacy of the conventional method of determining the planning target volume (PTV) and (c) the systematic and objective assessment of acute and late side-effects. Corrective actions to maintain or meet the standards are also reported. The localization of residual mammary gland using conventional methods (anatomy and/or palpation) was compared in 100 patients with US localization: conventional methods were often inadequate and thus the use of US in PTV determination is necessary. Portal film analysis helped reduce ideal margins from 20 mm to 11 mm. The amount of irradiated ispilateral lung, retrospectively calculated in 88 consecutive patients, appeared adequate to the chosen reference standard. The systematic study of late skin reactions had shown in some patients telangectasia regions outside the boost area: since 1991, a corrective action, decreasing the thickness of the customized immobilization cast inside the treatment area, from 2 mm to 0.2 mm, has been adopted. These examples show that the routine application of quality assurance procedures can help optimize radiation treatment.

Breast Neoplasms↗
PubMed1995

Hyperthermia and radiation therapy for inoperable or recurrent parotid carcinoma. A phase I/II study.

BACKGROUND: The treatment of advanced, inoperable, or recurrent parotid tumors represents a clinical challenge. The results obtained with conventional radiotherapy are disappointing. To improve the early response and local control of parotid tumors, local microwave hyperthermia was used in combination with ionizing radiation in a biinstitutional Phase I/II study. METHODS: From 1984 to 1991, 13 patients (20 lesions) with advanced (10 lesions) or recurrent (10 lesions) parotid tumors (15 primaries and the remaining 5 nodal metastases), were treated with 300-915 MHz of external hyperthermia after external irradiation. Heat was applied twice weekly at a minimum desired temperature of 42.0 degrees C for 30 minutes at steady state. Ionizing radiation was delivered using photon, electron, or mixed electron-photon beams; the prescribed total dose was 70 Gy and 30 Gy for untreated and previously treated lesions, respectively; the median computed total dose was 66 Gy for previously untreated patients (range, 56-70 Gy) and 30 Gy for previously irradiated patients (range, 28-32 Gy). RESULTS: Acute side effects were limited. Major acute toxicities included three patients (15%) with superficial necrosis, two of three who healed spontaneously in 4 and 6 months. Clinical response evaluated during the third month after the completion of therapy found that 16/20 patients (80%) had a complete response (CR), and 4 (20%) had a partial response. Four out of 16 patients who had CRs (20%) had a local recurrence, resulting in an actuarial local control at 5 years of 62.3 +/- 13.2%. CONCLUSIONS: The combined treatment of local microwave hyperthermia and ionizing radiation proved to be feasible and moderately toxic for patients with advanced, inoperable, or recurrent parotid tumors. Even if clinical result evaluation was not the study endpoint, early response, and 5-year local control rates were encouraging.

Adult↗
PubMed1994

The role of radiotherapy in the treatment of stage III non-small cell lung cancer: a survey of clinical practices in Lombardy, Italy, by the Airo*-Lombardia Cooperative Group.

AIMS AND BACKGROUND: The role of radiotherapy in the treatment of stage III non-small cell lung cancer is controversial. The aim of this survey was to investigate the use of this modality in current clinical practice in Lombardy, a highly industrialized region of northern Italy. METHODS: A questionnaire was sent to all 13 radiotherapy centers in Lombardy, covering statistical, clinical, technical and strategical aspects, and the responses were analyzed. RESULTS: A wide range of attitudes was observed among participating radiation oncologists; the percentage of cases treated with curative intent varied largely between centers (4-100%), as did the proportion of patients given to radiation only rather than combined modality treatment (5-100% vs 0-90%). CONCLUSIONS: An urgent need exists for better cooperation between all clinicians involved in lung cancer treatment, pursuing the goals of a more uniform clinical practice and a more aggressive clinical research attitude.

Carcinoma, Non-Small-Cell Lung↗
PubMed1994

Report of long-term follow-up in a randomized trial comparing radiation therapy and radiation therapy plus hyperthermia to metastatic lymph nodes in stage IV head and neck patients.

PURPOSE: The treatment of inoperable metastatic lymph nodes in patients with head and neck cancer represents a therapeutic challenge. Clinical results using conventional radiation therapy are disappointing; on the other hand, the evaluation of recent innovative radiotherapeutic methods is still pending. The end points of this analysis were focused on long-term local control, on its potential influence on survival, and on late toxicity of a previously reported randomized Phase III study comparing conventionally fractionated radical irradiation alone or combined with local hyperthermia in fixed and inoperable metastatic neck lymph nodes. METHODS AND MATERIALS: The medical records of 41 patients (44 nodes) with advanced locoregional Stage IV squamous cell cancer of the head and neck and randomized to treatment in the period 1985-1986 with irradiation alone (22/23 evaluable nodes) or combined with external hyperthermia (18/21 evaluable nodes), were re-evaluated. RESULTS: The statistically significant difference observed in "early" response (p = 0.0164) in favor of the combined treatment results in improved 5-year actuarial nodal control (p = 0.015). Clinical improvement noted in tumor control positively affects survival, leading to a statistically significant difference in survival at 5 years (p = 0.02). With respect to side effects, no clearly enhanced acute or late toxicity has been found; as severe late effects, two patients with bone necroses possibly related to the combined treatment have been observed. Thermal analysis failed to show a significant correlation between heating parameters and the end points of the study. CONCLUSION: This report with 5-year follow-up confirms the efficacy and the absence of severe toxicity of the combination of radical radiation and hyperthermia in the treatment of metastatic lymph nodes in Stage IV squamous cell carcinoma of the head and neck.

Carcinoma, Squamous Cell↗
PubMed1993

Cisplatin, hyperthermia, and radiation (trimodal therapy) in patients with locally advanced head and neck tumors: a phase I-II study.

PURPOSE: Hyperthermia is now being widely used to treat clinical malignancies especially combined with radiotherapy and more rarely with chemotherapy. The combination of heat, radiation, and chemotherapy (trimodality) can lead to potent interaction. The present Phase I-II study was conducted to evaluate the feasibility and acute toxicity of a combination of cisplatin, hyperthermia, and irradiation in the treatment of superficial cervical nodal metastases from head and neck cancer. METHODS AND MATERIALS: Eighteen patients with measurable neck metastases from previously untreated squamous cell head and neck tumors were entered into the trial. Therapy consisted of a conventional irradiation (total dose 70 Gy, 2 Gy five times a week) combined with a weekly administration of 20 mg/m2 iv of cisplatin and a total of two sessions of local external microwave hyperthermia (desired temperature of 42.5 degrees C for 30 min). RESULTS: Feasibility of the treatment was demonstrated. Acute local toxicity was mild; no thermal blisters or ulcerations were reported and only two patients experienced local pain during hyperthermia. Cutaneous toxicity appeared greater than in our previous studies with irradiation plus hyperthermia and irradiation plus cisplatin. Systemic toxicity was moderate with major toxic effects observed in three patients (World Health Organization (WHO) grade 3 anaemia). Even though it was not an aim of the study to evaluate the nodal response, we observed a complete response rate of 72.2% (95% confidence interval 51-93.4%), 16.6% of partial response and 11.1% of no change. CONCLUSION: The study confirms the feasibility of the combination of cisplatin, heat, and radiation with an acceptable toxicity profile. The trimodal therapy deserves further evaluation as a way to enhance the efficacy of irradiation in the treatment of nodal metastases from head and neck tumors.

Adult↗
PubMed1992

Radiation treatment of prostate bone metastases and the biological considerations.

This contribution on the biology and management of bone metastases from prostatic cancer is divided into three parts. The first details a study conducted at Stanford University on the prevention of bone metastases in the lumbar spine, in patients in whom the lumbar spine has been irradiated coincidental to the radiation treatment of the paraaortic lymph nodes. The incidence of metastases was significantly reduced in 71 patients in whom the apparently normal lumbar spine was irradiated, as compared to the incidence of metastases in 65 patients who received no lumbar irradiation. The implications of these observations on developing strategies for early, or preemptive, irradiation for bone metastases are discussed. In the second part, the optimum radiation dose and fractionation scheme for the palliation of overt bone metastases is addressed. Drawing largely from the work of Arcangeli et al., a total dose of 40-50 Gy*, fractionated at 2 Gy per day, seems to be the regimen of choice for enduring pain relief for most patients with prostatic metastases to bone. Finally, the recent utilization of strontium-89 in the palliation of advanced bone metastases is addressed. *The Gy is the current international unit of radiation. 1Gy = 100 Rad; 1cGy (centigray) = 1 Rad.

Bone Neoplasms↗
PubMed1992

Beam modifying devices in the treatment of early breast cancer: 3-D stepped compensating technique.

A 3-D compensating technique utilizing stepped brass filters to ensure an adequate dose distribution in the breast after conservative surgery is described. No compensation for lung inhomogeneity is applied. These compensators are part of a procedure which also involves the use of a rotatable half-beam block (HBB) and of an individualized immobilization cast. Results of patient dosimetry show a good agreement with dose prescription in the target volume (measured dose/prescribed dose = 100.9% +/- 1.8% at the reference point). Phantom dosimetry is discussed.

Breast Neoplasms↗
PubMed1992

[Comparison of acceptance tests of 5 linear electron accelerators for radiotherapy].

The acceptance tests of five electron linear accelerators have been analyzed to compare their completeness, the standards specified by the manufacturers and the measured deviations. Involved tests were relative to geometrical and mechanical parameters, photon and electron beam characteristics, dose monitoring systems, treatment table and safety systems. The comparison of acceptance tests has shown a significant nonuniformity, also due to the absence of a specific legislation; anyway, the measured deviations generally appeared to be within internationally recommended values.

Particle Accelerators↗