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Dive into the research topics where Antonio Cassio Assis Pellizzon is active.

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Featured researches published by Antonio Cassio Assis Pellizzon.


International Journal of Radiation Oncology Biology Physics | 2001

HIGH-DOSE-RATE BRACHYTHERAPY IN THE TREATMENT OF UTERINE CERVIX CANCER. ANALYSIS OF DOSE EFFECTIVENESS AND LATE COMPLICATIONS

Robson Ferrigno; Paulo Eduardo Ribeiro dos Santos Novaes; Antonio Cassio Assis Pellizzon; Maria Aparecida Conte Maia; Ricardo César Fogarolli; André Cavalcanti Gentil; João Victor Salvajoli

PURPOSE This retrospective analysis aims to report results of patients with cervix cancer treated by external beam radiotherapy (EBR) and high-dose-rate (HDR) brachytherapy. METHODS AND MATERIALS From September 1992 to December 1996, 138 patients with FIGO Stages II and III and mean age of 56 years were treated. Median EBR to the whole pelvis was 45 Gy in 25 fractions. Parametrial boost was performed in 93% of patients, with a median dose of 14.4 Gy. Brachytherapy with HDR was performed during EBR or following its completion with a dose of 24 Gy in four weekly fractions of 6 Gy to point A. Median overall treatment time was of 60 days. Patient age, tumor stage, and overall treatment time were variables analyzed for survival and local control. Cumulative biologic effective dose (BED) at rectal and bladder reference points were correlated with late complications in these organs and dose of EBR at parametrium was correlated with small bowel complications. RESULTS Median follow-up time was 38 months. Overall survival, disease-free survival, and local control at 5 years was 53.7%, 52.7%, and 62%, respectively. By multivariate and univariate analysis, overall treatment time up to 50 days was the only statistically significant adverse variable for overall survival (p = 0.003) and actuarial local control (p = 0.008). The 5-year actuarial incidence of rectal, bladder, and small bowel late complications was 16%, 11%, and 14%, respectively. Patients treated with cumulative BED at rectum points above 110 Gy(3) and at bladder point above 125 Gy(3) had a higher but not statistically significant 5-year actuarial rate of complications at these organs (18% vs. 12%, p = 0.49 and 17% vs. 9%, p = 0.20, respectively). Patients who received parametrial doses larger than 59 Gy had a higher 5-year actuarial rate of complications in the small bowel; however, this was not statistically significant (19% vs. 10%, p = 0.260). CONCLUSION This series suggests that 45 Gy to the whole pelvis combined with four fractions of 6 Gy to point A with HDR brachytherapy is an effective and safe fractionation schedule in the treatment of Stages II and III cervix cancer if realized up to 50 days. To decrease the small bowel complications, we decreased the superior border of the parametrial fields to the S2-S3 level and the total dose to 54 Gy.


Radiotherapy and Oncology | 2003

Results of high dose rate afterloading brachytherapy boost to conventional external beam radiation therapy for initial and locally advanced prostate cancer

Antonio Cassio Assis Pellizzon; W. Nadalin; João Vitor Salvajoli; Ricardo César Fogaroli; Paulo Eduardo Ribeiro dos Santos Novaes; Maria Aparecida Conte Maia; Robson Ferrigno

PURPOSE To evaluate the impact on biochemical control (bNED), acute and late gastro-intestinal (GI) and urological (GU) morbidity of initial and locally advanced prostate cancer treated with fractionated transrectal ultrasound-guided (TRUS) high dose rate after loading brachytherapy (HDR-B) as a boost to conventional external beam radiation therapy (EBRT). PATIENTS AND METHODS From March 1997 to February 2000 a total of 119 patients with any of the following characteristics were eligible for study entry: biopsy proven adenocarcinoma Gleason scored (GS), initial prostatic specific antigen (PSA) level dosage 1992 AJCC clinical stage T3a or less, and prostatic volume <60 cc. All patients had prior to HDR-B a course of EBRT 6 MV photons to a median dose of 45 Gy, in 1.8 Gy fractions, to the prostate and seminal vesicles only. HDR-B treatment planning and dosimetric calculations were generated with the Nucletron Planning System. Patients were grouped into two groups, according to their risk for biochemical failure: low-risk group without (LR) or with neoadjuvant total androgen deprivation (AD) prior to EBRT (LR+AD) and high-risk group without (HR) or with neoadjuvant AD (HR+AD), for bNED and dose-escalation protocol. LR encompassed patients who presented GS<6, T1 or T2a and or initial PSA<10 ng/ml, who were treated with 16 Gy (4 Gy fractions, b.i.d.) HDR-B. The remaining patients were grouped into HR or HR+AD and received 20 Gy (5 Gy fractions, b.i.d.) HDR-B. The planning was optimized using the standard geometric optimization. Biological effective doses (BED) for tumor control and late responding tissue were calculated using a alpha/beta ratio of 1.5 and 3 Gy, respectively. They were matched with bNED, acute and late gastrointestinal (GI) and urological (GU) morbidity, according to the RTOG/EORTC scoring criteria. RESULTS Median age of patients was 68 years (range 47-83), with a median follow-up of 41 months (range 18-48). The crude and actuarial biochemical controls (bNED) in 48 months for all patients were 69.5 and 75.3%, respectively. When grouped into LR, LR+AD, HR and HR+AD the actuarial bNED were 78.2, 76, 76 and 72.3% (P=0.89), respectively. Acute GU and GI morbidity G1-2 were seen in 18.5% (20/108) and 10.2% (11/108) of patients with spontaneous regression. Late GI and GU morbidity G1-2 were seen in 12% (13/108) and 4.6 (5/108) of patients, with no need of intervention. No acute or late G3-4 GU or GI morbidity was seen. CONCLUSIONS There are many advantages in HDR-B, but the most important ones are the capability of on-line dosimetry, quality control and the procedure being very conformal. There is a low incidence of GU and GI acute and late morbidity with acceptable bNED when treating initial and locally advanced prostate cancer with HDR-B as a boost to EBRT, but we still need to wait for results of phase III open trials that analyze HDR-B and conformal therapy.


Oral Oncology | 2011

EVALUATION OF LOW-LEVEL LASER THERAPY IN THE PREVENTION AND TREATMENT OF RADIATION-INDUCED MUCOSITIS: A DOUBLE-BLIND RANDOMIZED STUDY IN HEAD AND NECK CANCER PATIENTS

P.A.G. Carvalho; G.C. Jaguar; Antonio Cassio Assis Pellizzon; J.D. Prado; R.N. Lopes; Fabio Abreu Alves

The purpose of this prospective study was to determine the effect of the low-level laser in the prevention and treatment of mucositis in head and neck cancer patients. A total of 70 patients with malignant neoplasms in the oral cavity or oropharynx were evaluated. The patients were randomized into two low-level laser therapy groups: Group 1 (660nm/15mW/3.8J/cm(2)/spot size 4mm(2)) or Group 2 (660nm/5mW/1.3J/cm(2)/spot size 4mm(2)) starting on the first day of radiotherapy. Oral mucositis was assessed daily and weekly using the NCI and WHO scales. Oral pain was scored daily with a visual analogue scale before laser application. The patients in Group 1 had a mean time of 13.5days (range 6-26days) to present mucositis grade II, while the patients in Group 2 had a mean time of 9.8days (range 4-14days) (both WHO and NCI p=0.005). In addition, Group 2 also presented a higher mucositis grade than Group 1 with significant differences found in weeks 2 (p=0.019), 3 (p=0.005) and 4 (p=0.003) for WHO scale and weeks 2 (p=0.009) and 4 (p=0.013) for NCI scale. The patients in Group 1 reported lower pain levels (p=0.004). Low-level laser therapy during radiotherapy was found to be effective in controlling the intensity of mucositis and pain.


BMC Cancer | 2007

Whole brain radiotherapy for brain metastases from breast cancer: estimation of survival using two stratification systems

Gustavo Arruda Viani; Marcus S Castilho; João Victor Salvajoli; Antonio Cassio Assis Pellizzon; Paulo Eduardo Ribeiro dos Santos Novaes; Flavio S Guimarães; Maria A Conte; Ricardo César Fogaroli

BackgroundBrain metastases (BM) are the most common form of intracranial cancer. The incidence of BM seems to have increased over the past decade. Recursive partitioning analysis (RPA) of data from three Radiation Therapy Oncology Group (RTOG) trials (1200 patients) has allowed three prognostic groups to be identified. More recently a simplified stratification system that uses the evaluation of three main prognostics factors for radiosurgery in BM was developed.MethodsTo analyze the overall survival rate (OS), prognostic factors affecting outcomes and to estimate the potential improvement in OS for patients with BM from breast cancer, stratified by RPA class and brain metastases score (BS-BM). From January 1996 to December 2004, 174 medical records of patients with diagnosis of BM from breast cancer, who received WBRT were analyzed. The surgery followed by WBRT was used in 15.5% of patients and 84.5% of others patients were submitted at WBRT alone; 108 patients (62.1%) received the fractionation schedule of 30 Gy in 10 fractions. Solitary BM was present in 37.9 % of patients. The prognostic factors evaluated for OS were: age, Karnofsky Performance Status (KPS), number of lesions, localization of lesions, neurosurgery, chemotherapy, absence extracranial disease, RPA class, BS-BM and radiation doses and fractionation.ResultsThe OS in 1, 2 and 3 years was 33.4 %, 16.7%, and 8.8 %, respectively. The RPA class analysis showed strong relation with OS (p < 0.0001). The median survival time by RPA class in months was: class I 11.7, class II 6.2 and class III 3.0. The significant prognostic factors associated with better OS were: higher KPS (p < 0.0001), neurosurgery (P < 0.0001), single metastases (p = 0.003), BS-BM (p < 0.0001), control primary tumor (p = 0.002) and absence of extracranial metastases (p = 0.001). In multivariate analysis, the factors associated positively with OS were: neurosurgery (p < 0.0001), absence of extracranial metastases (p <0.0001) and RPA class I (p < 0.0001).ConclusionOur data suggests that patients with BM from breast cancer classified as RPA class I may be effectively treated with local resection followed by WBRT, mainly in those patients with single BM, higher KPS and cranial extra disease controlled. RPA class was shown to be the most reliable indicators of survival.


Radiation Oncology | 2006

Salvage for cervical recurrences of head and neck cancer with dissection and interstitial high dose rate brachytherapy

Antonio Cassio Assis Pellizzon; João Victor Salvajoli; Luiz Paulo Kowalski; André Lopes Carvalho

Salvage therapy in head and neck cancer (HNC) is a controversy issue and the literature is scarce regarding the use of interstitial high-dose rate brachytherapy (I-HDR) in HNC. We evaluated the long-term results of a treatment policy combining salvage surgery and I-HDR for cervical recurrences of HNC. Charts of 21 patients treated from 1994 to 2004 were reviewed. The crude local control rate for all patients was 52.4%. The 5- and 8-years overall (OS) and local relapse-free survival (LRFS) rates were 50%, 42.9%, 42.5% and 28.6%, respectively. The only predictive factor associated to LFRS and OS was negative margin status (p = 0.0007 and p = 0.0002). We conclude that complete surgery is mandatory for long term control and the doses given by brachytherapy are not high enough to compensate for microscopic residual disease after surgery.


Radiation Oncology | 2008

High-dose-rate brachytherapy for soft tissue sarcoma in children: a single institution experience

Gustavo Arruda Viani; Paulo Eduardo Ribeiro dos Santos Novaes; Alexandre A Jacinto; Celia B Antonelli; Antonio Cassio Assis Pellizzon; Elisa Y Saito; João Victor Salvajoli

PurposeTo report our experience treating soft tissue sarcoma (STS) with high dose rate brachytherapy alone (HBRT) or in combination with external beam radiotherapy (EBRT) in pediatric patients.Methods and materialsEighteen patients, median age 11 years (range 2 – 16 years) with grade 2–3 STS were treated with HBRT using Ir-192 in a interstitial (n = 14) or intracavitary implant (n = 4). Eight patients were treated with HBRT alone; the remaining 10 were treated with a combination of HBRT and EBRT.ResultsAfter a median follow-up of 79.5 months (range 12 – 159), 14 patients were alive and without evidence of disease (5-year overall survival rate 84.5%). There were no local or regional failures in the group treated with HBRT alone. One patient developed distant metastases at 14 months and expired after 17 months. In the combined HBRT and EBRT group, there was 1 local failure (22 months), and 3 patients developed pulmonary metastatic disease 18, 38 and 48 months after diagnosis and no these patients were alive at the time of this report. The overall local control to HBRT alone and HBRT plus EBRT were 100 and 90%, respectively. The acute affects most common were local erythema and wound dehiscence in 6 (33%) and 4 (22%) patients.Late effects were observed in 3 patients (16.5%).ConclusionExcellent local control with tolerable side effects have been observed in a small group of paediatric patients with STS treated by HBRT alone or in combination with EBRT.


Otolaryngology-Head and Neck Surgery | 2005

Treatment results on advanced neck metastasis (N3) from head and neck squamous carcinoma

André Lopes Carvalho; Luiz Paulo Kowalski; Ivan Marcelo Gonçalves Agra; Everton Pontes; Olímpio D. Campos; Antonio Cassio Assis Pellizzon

OBJECTIVE : To analyze the long-term results of patients with N3 neck metastasis from squamous carcinoma of the head and neck. STUDY DESIGN : This study is based on the analysis of a retrospective cohort of 224 previously untreated patients with squamous cell carcinoma of the head and neck and lymph node metastasis sized greater than 6 cm (N3) who were evaluated from 1981 to 1996. RESULTS : Fifty-four patients (24.1%) underwent neck dissection, 137 underwent radiotherapy alone (61.2%), and 33 received only supportive care (14.7%). Control of the neck metastasis was achieved in 46 cases among the treated ones (24.1%), varying from 51.9% for the patients who underwent surgery to 13.1% for radiotherapy alone (P >0.001). Exclusive distant metastasis occurred in 37.0% of the cases who had control of the neck disease. The 3-year overall survival rates were 17.9% for patients who underwent surgery and 7.0% for radiotherapy alone (P = 0.003). The multivariate analysis showed as independent predictive factors the treatment approach (P >0.001) and tumor site (P = 0.016). CONCLUSIONS : This study confirms the poor prognosis of patients with N3 neck disease, mainly when treated by radiotherapy alone. A radical neck dissection associated with adjuvant radiotherapy is indicated whenever feasible. Because of the high rate of distant metastasis, protocols including adjuvant chemotherapy should be investigated.


American Journal of Clinical Oncology | 2009

High dose rate and external beam radiotherapy in locally advanced prostate cancer.

Gustavo Arruda Viani; Antonio Cassio Assis Pellizzon; Flavio S Guimarães; Alexandre A Jacinto; Paulo Eduardo Ribeiro dos Santos Novaes; João Vitor Salvajoli

Purpose:To report the outcomes and toxicity of high dose rate brachytherapy as a boost for localized prostate cancer. Materials and Methods:Between 1997 and 2000, the medical records of 131 patients with prostate adenocarcinoma who were treated with external beam radiation therapy and high dose rate brachytherapy, were retrospectively analyzed. Furthermore, 55% of the patients received neoadjuvant/concurrent or adjuvant androgen deprivation therapy. Patients were stratified into 2 groups. Group 1 included 65 patients with Gleason score 7, pretreatment prostate specific antigen (PSA) between 10 and 20 ng/mL, and clinical stage T2b. Group 2 included 66 patients with Gleason score between 8 and 10, PSA greater than 20 ng/mL, and clinical stage greater than T2b. Results:At a median follow-up of 62.8 months, the 5-year biochemical control (BC) rate, as defined by the American Society for Therapeutic Radiology and Oncology Phoenix Consensus panel statement, was 81% and overall survival was 91%. BC in Groups 1 and 2 were 87% and 71%, respectively. On univariate analysis risk group, pretreatment PSA and age were significant predictors of BC. However, on multivariate analysis only pretreatment PSA was significant. Using the Radiation therapist oncology group criteria, there were 2 (1.5%) cases of grade 3 acute urinary toxicity. Regarding late side effects (n = 5), 4% of patients had grade 3 genitourinary toxicity and no grade 4 complication was observed. Conclusions:External beam radiation therapy and high dose rate brachytherapy for prostate cancer resulted in excellent BC, and overall survival with minimal severe, acute, or late complications.


Brachytherapy | 2013

Tumor control, eye preservation, and visual outcomes of ruthenium plaque brachytherapy for choroidal melanoma

Daniel Grossi Marconi; Douglas Guedes de Castro; Liêvin Matos Rebouças; Gabriel Oliveira Bernardes Gil; Ricardo César Fogaroli; Maria Aparecida Conte Maia; Maria Leticia Gobo Silva; Antonio Cassio Assis Pellizzon; Maria Marta Motono Chojniak

PURPOSE To evaluate outcomes in patients with posterior choroidal melanoma treated with ruthenium ((106)Ru) brachytherapy. METHODS AND MATERIALS A retrospective single institutional analysis of 83 of 94 consecutive patients who underwent (106)Ru brachytherapy was performed. Disease was mainly staged as small- and medium-sized nonmetastatic melanoma. The main parameters evaluated were tumor control (local control [LC] and progression-free survival [PFS]) and ocular preservation (enucleation-free survival [EFS]). Besides, functional evaluation was performed and complications were described. RESULTS The median follow-up was 39 (6-83) months. The median values of height and maximal basal diameter were 4.3 and 9.3mm, respectively. Median apical and basal doses were 100 and 307Gy, respectively. The actuarial 2-year LC, PFS, and EFS were 96.2%, 96.2%, and 95.5%, respectively. Actuarial 5-year LC, PFS, and EFS were 93.6%, 93.6%, and 84.1%, respectively. Preinsertion visual acuity (VA) maintenance was 34% (equal or better than before treatment). Approximately 56% of patients stayed with a minimum functional VA of 0.1 or more, from whom more than half stayed with 0.5 or more. Cataract was seen in 16% of treated eyes, and glaucoma was the rarest complication, with an incidence of 3%. CONCLUSIONS Small- and medium-sized choroidal melanomas can be adequately treated with (106)Ru brachytherapy, with high rates of tumor control and ocular preservation. Moreover, acceptable incidence of complications such as glaucoma and cataract are seen, and a reasonable part of patients stay with a minimum functional VA.


Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 2005

Interstitial high-dose-rate brachytherapy combined with cervical dissection on head and neck cancer

Antonio Cassio Assis Pellizzon; Paulo Eduardo Ribeiro dos Santos Novaes; Maria Aparecida Conte Maia; Robson Ferrigno; Ricardo César Fogarolli; João Vitor Salvajoli; Luiz Paulo Kowalski

The literature is scarce regarding the use of interstitial high‐dose‐rate brachytherapy (I‐HDR) as adjuvant treatment of the cervical region, and most reports are focused on primary tumors of the mobile tongue and oropharynx. We evaluated the outcome and morbidity related to an institutional treatment policy, using I‐HDR as the sole adjuvant treatment or in combination with external beam radiotherapy (EBRT) at the Departments of Radiation Oncology and Head and Neck Surgery, Hospital do Cancer, Sao Paulo, Brazil.

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João Victor Salvajoli

Federal University of São Paulo

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Robson Ferrigno

Pontifícia Universidade Católica de Campinas

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Luiz Paulo Kowalski

National Institute of Standards and Technology

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Gustavo Arruda Viani

Faculdade de Medicina de Marília

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André Lopes Carvalho

Johns Hopkins University School of Medicine

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Ademar Lopes

University of São Paulo

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