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R Ragona

Publications and source records attributed to R Ragona.

At least 19 recordsLinked to original sources

CT-MRI image fusion for delineation of volumes in three-dimensional conformal radiation therapy in the treatment of localized prostate cancer.

The objective of this study was to assess the utility of CT-MRI image fusion software and compare both prostate volume and localization with CT and MRI studies. We evaluated the differences in clinical volumes in patients undergoing three-dimensional conformal radiation therapy for localized prostate cancer. After several tests performed to ensure the quality of image fusion software, eight patients suffering from prostate adenocarcinoma were submitted to CT and MRI studies in the treatment position within an immobilization device before the start of radiotherapy. The clinical target volume (CTV) (prostate plus seminal vesicles) was delineated on CT and MRI studies and image fusion was obtained from the superimposition of anatomical fiducial markers. A comparison of dose-volume histograms relative to CTV, rectum, bladder and femoral heads was performed for both studies. Image fusion showed a mean overestimation of CTV of 34% with CT compared with MRI. Along the anterior-posterior and superior-inferior direction, CTV was a mean 5 mm larger with CT study compared with MRI. The dose-volume histograms resulting from CT and MRI comparison showed that it is possible to spare a mean 10% of rectal volume and approximately 5% of bladder and femoral heads, respectively. This study confirmed an overestimation of CTV with CT images compared with MRI. Because this finding only allows a minimal sparing of organs at risk, considering the organ motion during each radiotherapy session and the excellent outcomes of prostate cancer treatment with CT based target identification, we are still reluctant to reduce the CTV to that identified by MRI.

Adenocarcinoma↗

[Complications of tracheostomy in critically ill patients: comparison of dilation and surgical techniques].

The tracheotomy, one of the oldest surgical procedures, has in recent years been the focus of particular attention given the undoubted, and not always justified, increase in indications, and by the introduction of dilatational tracheotomy techniques, particularly in critically patients. The present work compares the standard surgical tracheotomy with the more recent percutaneous techniques (Ciaglia dilatational tracheotomy and Fantoni translaryngeal tracheotomy). In particular, the relationship between the technique adopted, timing and complications were analyzed for 215 tracheotomies performed at different Intensive Care Units at our Hospital between 1993 and 1998 (106 performed using the standard surgical technique, 51 with the Ciaglia technique and 58 with the Fantoni technique). The pre-operative oro-tracheal intubation time ranged between 4-54 days (17 tracheotomies performed before oro-tracheal intubation). The results of this study showed that percutaneous techniques present fewer early post-operative complications (severe bleeding, erosive stomitis, dislocation of the cannula) and above all fewer sequelae in time (tracheal stenosis, tracheomalacia). The surgical procedures are shorter and nursing is limited to a few days which certainly results in a savings in health care resources. After decannulation, the esthetic result in patients that underwent the dilatational tracheotomy can be considered excellent. Among the disadvantages one must recall the possible dislocation of the cannula immediately after surgery: forced reinsertion of the cannula exposes the patient to the risk of creating a dangerous false route. The results obtained are statistically significant and in line with those found in the literature. The conclusion is drawn that, when performed by skilled surgeons and aided by endoscopy, the percutaneous tracheotomy techniques are the method of choice for patients in critical areas.

Adolescent↗

Phase II randomized trial comparing vinorelbine versus vinorelbine plus cisplatin in patients with recurrent salivary gland malignancies.

BACKGROUND: Some previous studies have shown that vinorelbine (VNB) is active in recurrent salivary gland tumors. METHODS: Between April 1993 and April 1997, 36 patients in a Phase II randomized trial received either cisplatin, 80 mg/m(2), on Day 1 plus VNB, 25 mg/m(2), on Days 1 and 8 (every 3 weeks) (for a minimum of 3 cycles (Arm A [16 patients]), or VNB, 30 mg/m(2)/week, (for a minimum of 9 wks) (Arm B [20 patients]). There were 23 males and 13 females with a median age of 59 years (range, 20-74 years) and a median Eastern Cooperative Oncology Group performance status of 1 (range, 0-2). Four patients had been treated with prior surgery (S) or radiotherapy (RT), 27 patients had been treated with S plus RT, and 5 patients had been treated with S plus RT plus mitoxantrone. Eighteen patients had major salivary gland tumors, and 18 patients had minor salivary gland tumors; 9 patients had adenocarcinoma, 22 patients had adenoid cystic carcinoma, 1 patient had a malignant mixed carcinoma, 3 patients had undifferentiated carcinoma, and 1 patient had a mucoepidermoid carcinoma. The site of recurrence was local in 16 patients, local plus metastatic in 5 patients, and metastatic only in 15 patients. These characteristics were well balanced between the 2 arms. RESULTS: In Arms A and B a complete response (CR) was noted in 3 patients (19%) and no patients, respectively; a partial response (PR) was noted in 4 patients (25%) and 4 patients (20%), respectively; no change was noted in 6 patients (37.5%) and 9 patients (45%), respectively; and progressive disease was noted in 3 patients (19%) and 7 patients (35%), respectively. The median duration of the CR was 15+ months (range, 6-27+ months) and for PR the median duration was 7.5 months (range, 3-11+ months) and 6 months (range, 3-9 months) in Arms A and B, respectively. Number of patients surviving > 12 months was 6 versus 1 in Arms A and B, respectively (P < 0.05). Grade 2-3 nausea and emesis was statistically higher (P < 0.001) in Arm A; there was no significant difference with regard to other side-effects between the two treatment arms. CONCLUSIONS: VNB is a drug with moderate activity in salivary gland malignancies. The combination of cisplatin plus VNB was found to be more active than VNB alone, with a good number of CRs and long-term survivors reported in the current study.

Adult↗

Survival in patients with recurrent squamous cell head and neck carcinoma treated with bio-chemotherapy.

BACKGROUND: We have shown that rIL-2 administration in recurrent head and neck cancers induces a tumor-specific T-lymphocyte reactivity and tumor regression; in a pilot study we have shown a safe and effective administration of rIL2 after cisplatin + 5-fluorouracil. Long-term results are not known. METHODS: Thirty patients with recurrent-persistent head and neck cancer were treated with cisplatin (100 mg-m(2)) d.1,5-fluorouracil (1 gr-m(2)-d c.i. 96 h), and SQ rIL-2 (4.5 M IU day 8 to 12 and 15 to 19) every 3 weeks. RESULTS: The overall response rate was 53.3% (95% CI; 34.4-72.3%): 26.6% complete response (CR) (8 patients) and 26.6% partial response (PR) (8 patients); 6 patients had SD (20%), 8 had PD (26.6%). The median follow-up was 36 months (range, 28-44). The median CR duration is 16.2 months (8.5-39+); the median survival duration of this group has not been reached. The median PR duration was 7.2 months (3-10); the median survival was 13.3 months (10-26). The median overall survival was 14 months. CONCLUSIONS: The most impressive finding is the very long survival of CRs patients. This outcome has been reported in other cancer patients with a CR after IL-2 therapy.

Adult↗

[Characterization of a diode system for in vivo dosimetry with electron beams].

PURPOSE: Current quality assurance regulation stresses the basic role of in vivo dosimetry. Our study evaluates the usefulness and reliability of semiconductor diodes in determining the electron absorbed dose. MATERIAL AND METHODS: P-type EDE semiconductor detectors were irradiated with electron beams of different energies produced by a CGR Saturn Therac 20. The diode and ionization chamber response were compared, and effect of energy value, collimator opening, source skin distance and gantry angle on diode response was studied. RESULTS: Measurements show a maximum increment of about 20% in diode response increasing the beam energy (6-20 MeV). The response also increases with: collimator opening, reaching 5% with field sizes larger than 10x10 cm2 (with the exception of 20 MeV energy); SSD increase (with a maximum of 8% for 20 MeV); transversal gantry incidence, compared with the diode longitudinal axis; it does not affect the response in the interval of +/- 45 degrees. Absorbed dose attenuation at dmax, due to the presence of diode on the axis of the beam as a function of electron energy was also determined : the maximum attenuation value is 15% in 6 MeV electron beams. A dose calculation algorithm, taking into account diode response dependence was outlined. In vivo dosimetry was performed in 92 fields for 80 patients, with an agreement of +/-4 % (1 SD) between prescribed and measured dose. DISCUSSION AND CONCLUSIONS: It is possible to use the EDE semiconductor detectors on a quality control program of dose delivery for electron beam therapy, but particular attention should be paid to the beam incidence angle and diode dose attenuation.

Electrons↗

Adjuvant radiotherapy influences the survival of patients with squamous carcinoma of the head and neck who have poor prognoses.

The treatment of carcinoma of the head and neck in recent years has improved significantly, chiefly thanks to progress in surgery and radiotherapy. Despite these advances, the survival statistics reported in the literature show no appreciable evidence of radical improvement. The aims of this study were to evaluate the impact on survival achieved with the combination of surgical and postoperative radiotherapy in patients with advanced head and neck carcinomas and to identify the prognostic value of several host- and tumor-related factors that can influence the results of combined treatment. We retrospectively reviewed the medical records of 394 patients with stage III and IV carcinoma of the head and neck, of whom 170 (43%) underwent surgery alone and 224 (57%) received combined surgery and postoperative radiotherapy. The 394 patients were stratified for a set of variables including the patient's condition, the characteristics of the tumor, and the modality of treatment. Univariate analysis revealed that coexistent medical diseases, the size and site of the primary lesion, the stage of the tumor, and certain pathologic features had a negative impact on survival. Multivariate analysis showed that the removal of lymph nodes and postoperative radiotherapy can have a positive influence and can improve the prognosis. We compared the survival rates of the patients treated with surgery alone with those of the patients who underwent combined treatment, and we observed that the two survival curves were comparable, even if there was a bias because the combined treatment group consisted of patients with negative prognostic factors. The meaning of these results, compared with data from the literature, has been discussed.

Adult↗

Carcinoma of the larynx in the elderly: analysis of potentially significant prognostic variables.

The incidence reported for carcinomas of the head and neck currently peaks between the sixth and seventh decades of life. In this retrospective study we were interested in learning whether age is a potentially significant prognostic factor for survival. We considered a set of variables in a series of 134 patients, divided into two groups; between 65 and 70 years of age, and older than 70. Stage I-II tumors were present in 44 patients, while locally advanced lesions (stages III-IV) were present in 90. Statistical analysis of survival was performed using the actuarial survival rates according to Kaplan-Meier; significance was evaluated using the log-rank test. Multivariate analysis was performed according to the Cox logistic regression model to determine the prognostic significance of any of the variables. Univariate analysis was performed on a series of variables regarding the patient, tumor and treatment. In the younger group, age appeared to be a favorable prognostic factor. Tumor size had a significant effect on disease-free survival, both globally and between the two groups (p < 0.05). Lymph node status substantially influenced the five-year survival rate (p = 0.001). Tumor invasion of the lymph nodes led to a difference between the two groups. Survival was lower in the younger than in the older group. There was a significant difference (p < 0.01) in survival between patients who had undergone surgery (75%) and those who received radiotherapy alone (33%). Multivariate analysis of these variables showed that disease stage, and treatment of lymph nodes were both significant (p = 0.0016 and p = 0.0002, respectively). Survival rates for the so-called "young elderly" (65-70 years) are generally higher than that for those aged 70 and over. Following accurate and comprehensive assessment by the anesthesiologist and the internist, and appropriate adjustment of the patient's nutritional and metabolic status, combined radical surgery and radiotherapy can and must be performed. Minimal palliative interventions, in the belief that tumor growth is biologically less aggressive in the elderly patient, should be avoided.

Aged↗

Treatment of malignant neoplasms of the parotid gland.

In this study we evaluated the effects of surgical and radiotherapy treatment on local control in 126 patients with malignant tumors of the parotid gland. The most frequently observed malignant tumors were high-grade tumors (68%). Surgical treatment was performed in 81 patients (83.5%). Total conservative parotidectomy was the most frequent procedure (74%), and radiotherapy was performed in 81 patients (83.5%). The global survival rate was approximately 54% at 5 years, whereas disease-free survival was 47% at 5 years. No statistically significant difference in survival rate was found between conservative (52% at 5 years) and radical treatment of the seventh cranial nerve (43% at 5 years). The incidence of recurrent cancer was 25.7% (25 of 97), of which 88% developed during the first 2 years. We report some of the clinical and histologic factors that can influence the prognosis of the disease.

Adolescent↗

[Multi-center study of recurrent nasal sinus polyposis: prognostic factors and possibility of prophylaxis].

Today, surgery is the treatment of choice for nasal sinus polyposis. Nevertheless, although meticulous surgery does "per se" reduce the percentage of recurrences, there are cases where even the most painstaking removal of the entire pathology cannot prevent recurrence. Therefore recurrences do not appear linked to the type of surgery; rather onset appears linked to intrinsic, only partially recognizable factors responsible for the primary and secondary polypogenesis. In order to identify negative prognostic factors which might be implicated in recurrences, the present study extrapolated the data from forms on 181 patients who had undergone surgery for nasal sinus polyposis and subjected it to multivariance analysis. These patients were recruited during the course of a multicenter study with the participation of 12 ENT Centers in Piemont and Liguria. The recurrence rate was 13%. In analyzing unfavorable factors prognosticating recurrence, thirteen parameters were examined. Nine of these (age, sex, severe deviation of the septum causing restriction, severe turbinate hypertrophy, surgery or repeat surgery for recurrence, type of macro-micro endoscopic surgery, allergy to seasonal inhalants, allergy to perennial inhalants, mixed allergies) did not prove to have any significance in recurrences. The presence of bilateral involvement of the sinus system presented a negative trend as regards recurrences while involvement of more than one subsite (anterior ethmoid, posterior ethmoid, maxillary sinus, sphenoid), ASA and NSAID intolerance and abundant eosinophilic infiltration in the mucous chorion proved statistically significant (p < 0.05 for all three parameters) for recurrence. Post-operative topic prophylactic treatment with steroids (beclomethasone) or anti-H1 drugs (azelastin, HCl) did not appear to affect the onset of recurrence although it did have a positive effect on subjective symptoms.

Anti-Inflammatory Agents↗

[Evaluation of various phonatory parameters in laryngectomized patients: comparison of esophageal and tracheo-esophageal prosthesis phonation].

Today there is increased need for an objective comparison between the various post-total laryngectomy phonatory rehabilitation techniques. This survey involves 20 patients who, after total laryngectomy, underwent rehabilitation using the esophageal voice (n = 10) or through the application of a secondary tracheal-esophageal prosthesis (n = 10). The multivariate analysis indicated that the only phonatory parameter which differed significantly between the two types of voice was the maximum phonation time (MPT) (p < 0.01). The MPT was markedly longer in patients with the tracheal-esophageal prosthesis. In patients with prosthesis, the Mann-Whitney test highlighted better figures for the following parameters: MPT (p = 0.0003), GP (maximum number of words that can be read in one breath) (p = 0.009), maximum intensity level (MIL) (p = 0.019), Shimmer (p = 0.008) and noise-to harmonics ratio (NHR) (p = 0.049). Furthermore, the Spearman test proved there is a relationship between MIL and GP, and between Pitch and Shimmer. Therefore, the tracheal-esophageal prosthesis seems to offer better phonatory energy and phonatory duration for every breath. However, these methods of objective inquiry need to be further developed so that comparison-among the different authors and among the different rehabilitation methods-can be made easier than it is now.

Aged↗

[Therapeutic strategies for the treatment of parotid gland malignancies].

Parotid gland neoplasms include a quite heterogeneous group of histotypes with markedly different biological characteristics and evolution, thus requiring different forms of treatment. The present study evaluated the effects surgery and radiotherapy have on local disease control, survival rates and onset of locoregional recurrences. 126 malignant parotid tumors were examined (59 males, 67 females; age range 11 to 88 years; mean age 62 years) with a minimum of 1 year follow-up. The most malignant tumors were those most frequently seen in this case study (68%). Surgery was performed in 81 subjects (83.5%). Conservative total parotidectomy was the procedure most frequently performed (60/81, 74%). The overall 5-year survival rate was around 54% while 47% were "disease-free" patients at 5 years. When the subjects were broken down into 2 groups according to the degree of malignancy (high or low), the survival curve for disease-free subjects showed some differences (respectively 52% and 42%). The choice of treatment for the primary T significantly affect survival. Radiotherapy alone proved much less satisfactory than surgery (p < 0.01). The 5-year survival rate following a combination of surgery and subsequent radiotherapy was 52%, while it was 47% for those treated by surgery alone. An examination of the type of surgery performed revealed a difference in survival between those treated with preservation of the VII cranial nerve (52% at 5 years) and the more radical surgery (43% at 5 years) although this difference was not statistically significant. The incidence of recurrence was 25.7% (25 cases out of 97), of which 88% arose within the first 2 years. In conclusion, it has been seen that malignant parotid gland neoplasms are highly aggressive and the treatment of choice appears to be surgery plus radiotherapy whenever the clinical-biological features of the neoplasm warrant it. The surgical approach to the facial nerve should be as conservative as possible, reserving utmost radicality for the most advanced cases compromising the adjacent structures.

Adolescent↗

Hormonally induced modulation in the phosphate metabolites of breast cancer: analysis of in vivo 31P MRS signals with a modified prony method.

A modified Prony method (MPM) was applied to analyze the main signals present in spatially resolved 31P NMR spectra of MCF7 breast tumors implanted in nude mice. First, the method was tested on synthetic data to establish its limits of reliability. Its performance with respect to peak identification and quantification of signal intensities was then exploited on data from three implanted tumors during hormonal manipulation with estrogen and the antiestrogenic drug tamoxifen. The phosphomonoester peak was resolved into phosphocholine (PC) and phosphoethanolamine (PE). Treatment with tamoxifen led to a significant reduction in the PE to PE+PC peak amplitude ratio in the tumors under consideration. MPM analysis also revealed the presence of two different inorganic phosphate pools: a larger acidic pool and a smaller alkaline pool during estrogen-induced growth and the reverse during tumor regression.

Animals↗

[Prognostic factors in the treatment of carcinoma of the cervix uteri in IB-IIA stage. Retrospective study].

January, 1977, to December, 1990, 311 patients with stage IB-IIA cervix carcinoma were treated at the Radiotherapy Department of the University of Turin. The distribution by stage was: 232 T1b (74.6%) and 79 T2a (25.4%). One hundred and eighty-nine patients (77% T1b-23% T2a) underwent preoperative radiotherapy, 63 patients (58% T1b-42% T2a) radiotherapy alone and 59 (85% T1b-15% T2a) postoperative radiotherapy. The first group of patients was treated according to three treatment protocols, based on different surgical procedures. During the median follow-up period of 86 months (82.6% of the patients underwent a minimum 3-year follow-up), 55 locoregional relapses (17%) and 21 extrapelvic metastases (7%) were observed. The 5-year NED survival rate and local control was 80%. The prognostic factors which significantly influenced survival in the univariate analysis, were: disease stage (p < .01), age (p < .05), the period between first symptom and therapy (p = .01), treatment protocols (radiotherapy combined with surgery versus radiation therapy alone: p < .05), residual disease after brachytherapy (p < .01), nodal status (p < .00001). In the radiotherapy alone group, the total dose influence on survival was not statistically significant (p = .12). In our series, histology and surgical procedures did not seem to influence prognosis. In the multivariate analysis, treatment protocol, age and residual disease after brachytherapy did not influence the prognosis, whereas the total dose of radiotherapy, pain (as first symptom) and Wertheim-Meigs surgery approach are prognostic factors. Severe late-effects were 17: 13 in the radiotherapy plus surgery protocol and 4 in the radiotherapy alone protocol. The incidence of major complications seems to correlate with surgical impact.

Adult↗

[Identification of clinical, biological and prognostic factors in recurring squamous cell carcinoma of the head and neck].

Many studies have been performed to determine some prognostic factors for malignant head and neck tumors. Defining the clinical and biological features would enable one to predict the progression of the disease and plan treatment. The aim of the present study has been to identify what host and neoplasm characteristics provide prognostic indication of possible recurrences. A group of 380 patients with squamous cell carcinoma of the head and neck was studied. The neoplasm was located in the following sites: 257 larynx-hypopharynx, 69 oropharynx, 54 oral cavity. At the present time 309 of these subjects are still alive and disease free while 71 have had recurrences. Analyses were performed on various variables regarding the patient, neoplasm and histology. Multivariante analysis of these prognostic factors was performed using the PLR-BMDP program. The time of recurrence in the primary tumor site and at the lymph node level was evaluated using the Kaplan-Meier method. Of the 28 variables analyzed 16 had no effect on the probability of recurrence. Two variables reduced the risk of recurrence: age over 61 years (p < 0.05) and primarily intra and peritumoral lymphocyte infiltration (p = 0.06). Of the data regarding the patient, age lower than 61 years and presence of associated internal pathologies (i.e. bronchial pneumonia and hepatitis) appeared to significantly facilitate the appearance of recurrence. The characteristics of the neoplasm which appear to effect recurrences are: tumor site (hypopharynx), presence of lymph node metastases, morphological elements of tissue spread (vascular invasion, plasmocyte infiltration), capsular breakdown, positive margins and post-operative infection. In conclusion, it can be asserted that technical development of multifactorial analysis has made it possible to identify important prognostic factors and quantify their impact on the evolution of a neoplasm.

Adult↗

Multiexponential T2 relaxation in Fricke agarose gels: implications for NMR dosimetry.

NMR relaxation times T1 and T2 of agarose and Fricke agarose gels have been measured in the range 17-51 MHz. The analysis of the spin echo curves indicates a multiexponential behaviour, characterized by three components, at all the examined frequencies. The relative T2 values, ranging from a few to a hundred milliseconds, can be attributed to different species of water molecules present in the gel. Two of these components are characterized by relaxation rates R2a and R2b, more sensitive than R1 to gamma irradiation, the sensitivity S being S(R1) = 0.066 s-1 Gy-1, S(R2a) = 0.088 s-1 Gy-1, S(R2b) = 0.17 s-1 Gy-1. The three T2 values decrease as a function of frequency, but no gain in dose sensitivity is obtained by changing the working frequency in the examined range. The relaxivity of agarose gels containing ferrous or ferric ions has also been measured and found to be different from those of the corresponding solutions in the absence of agarose. Thus it was possible to estimate the irradiation yield from three independent parameters, R1, R2a and R2b. No effect of the dose rate or of the source energy has been observed for any of these parameters.

Biophysical Phenomena↗