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Dive into the research topics where Onivaldo Cervantes is active.

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Featured researches published by Onivaldo Cervantes.


American Journal of Surgery | 1998

Results of a prospective trial on elective modified radical classical versus supraomohyoid neck dissection in the management of oral squamous carcinoma

Ricardo R. Brentani; Luiz Paulo Kowalski; José F. Soares; Humberto Torloni; Raimunda N. Pereira; Mauro K. Ikeda; Roberto P. Andrade; José Magrin; Roberto E.V. Miguel; Carlos R. Santos; Leda M.B. Saba; Joao V. Salvajoli; Maria P. Curado; José C. Oliveira; Paula O. Montandon; Márcio M. Machado; Giovana F. Denofrio; Waldyr C. Quinta; Rene B. Alvarez; Rita C.G. Alencar; Alberto Rosseti Ferraz; Lenine Garcia Brandão; Claudio Roberto Cernea; Luiz Roberto Medina dos Santos; Virgilius Araujo Filho; Avelino Antonangelo Filho; Joao L.F. Silva; Romualdo Della-Molle; Carlos V. Feriancic; Paulo Campos Carneiro

BACKGROUND Elective treatment of the neck in oral squamous cell carcinoma has changed over the last 20 years. The main object of this report is to present the results of a multi-institutional prospective study designed to compare standard treatment with modified radical classical neck dissection (MRND) to supraomohyoid neck dissection (SOH) in the management of the clinically negative neck in oral cancer patients. PATIENTS AND METHODS A total of 148 patients were included in the trial. All patients had previously untreated T2 to T4 N0 squamous cell carcinoma of the oral tongue (62 cases), floor of the mouth (49 cases), inferior gingiva (12 cases), or retromolar trigone (25 cases). Tumor stages were T2, 91; T3, 27; and T4, 30. There were no significant imbalances between groups. RESULTS The false-negative rate was 28%, and most positive nodes were sited at level II and III. Complications were seen in 41% of MRND patients and in 25% of SOH patients (P = 0.043). Median total duration of hospitalization was 9 days in MRND patients and 7 days in the SOH group. To date, 19 and 16 patients presented with local and neck recurrences, respectively. The 60-month actuarial survival rates were 63% in the MRND group and 67% in the SOH group (P = 0.7150). CONCLUSIONS This study demonstrates that the recurrence and survival rates were similar in both groups. SOH neck dissection can be recommended as standard elective treatment for patients with T2-T4 oral squamous cell carcinomas.


Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 1999

End results of a prospective trial on elective lateral neck dissection vs type III modified radical neck dissection in the management of supraglottic and transglottic carcinomas

Ricardo R. Brentani; Luiz Paulo Kowalski; José F. Soares; Humberto Torloni; Raimunda N. Pereira; Mauro Kasuo Ikeda; Roberto Paulo de Andrade; José Magrin; Roberto Elias Vilella Miguel; Carlos Roberto dos Santos; Leda Maria Buazar Saba; João Victor Salvajoli; Maria Paula Curado; José Carlos de Oliveira; Paula O. Montandon; Márcio M. Machado; Giovana F. Denofrio; Waldyr de Castro Quinta; Rene B. Alvarez; Rita C.G. Alencar; Benedito Valdecir de Oliveira; Gil Ramos; Lysandro S. Antunes; Jozias de Andrade Sobrinho; Abrão Rapoport; Marcos Brasilino de Carvalho; Antonio Sérgio Fava; José Francisco de Góis Filho; José Francisco Salles Chagas; Jossi Ledo Kanda

Either modified type III radical neck dissection (MRND) or lateral neck dissections (LNDs) are considered valid treatments for patients with laryngeal carcinoma with clinically negative neck findings (N0). The object of this prospective study was to compare complications, neck recurrences, and survival results of elective MRND and LND on the management of laryngeal cancer patients.


Journal of Voice | 2002

Noise-to-Harmonics Ratio as an Acoustic Measure of Voice Disorders in Boys ☆

Geraldo Pereira Jotz; Onivaldo Cervantes; Márcio Abrahão; Flávio A. P Settanni; Elisabete Carrara-de Angelis

This prospective study assessed the efficacy of computerized noise-to-harmonics ratio (NHR) to quantify perceptual and endoscopic findings of dysphonia and/or structural lesion of the vocal fold. Fifty Brazilian boys without vocal complaints were submitted to computerized, perceptual, and endoscopic examination. Thirty boys were dysphonic--3 were classified into the grade category, 5 into breathiness, 9 into roughness, and 15 into grade/breathiness. Vocal fold lesions were observed in 25 boys (17 nodules and 8 cysts). The Mann-Whitney U test revealed that NHR was significantly higher in boys with a structural lesion (p = 0.007) and in boys with dysphonia (p < 0.0001). However, according to a logistic regression model, only the occurrence of dysphonia was explained by NHR; the risk for having dysphonia increased approximately twice (odds ratio = 1.92, 95% confidence interval = 1.3-2.9) with each increase of 0.01 in NHR. Our results suggest that noise is a useful quantitative index to confirm a perceptual diagnosis of dysphonia and to evaluate quantitative changes in a dysphonic voice over time. However, we believe that computerized analysis should be used as a complement, rather than a substitute, for perceptual evaluation. Further studies with a larger sample are required to investigate the relationship between noise and lesions of the vocal folds.


Brazilian Journal of Medical and Biological Research | 2005

Changes in clinical and laboratory findings at the time of diagnosis of primary hyperparathyroidism in a University Hospital in São Paulo from 1985 to 2002

Monique Nakayama Ohe; Rodrigo Oliveira Santos; Elizabete Ribeiro Barros; A. Lage; Ilda Shizue Kunii; Márcio Abrahão; Onivaldo Cervantes; Omar M. Hauache; Marise Lazaretti-Castro; José Gilberto H. Vieira

In contrast to most developed countries, most patients with primary hyperparathyroidism in Brazil are still symptomatic at diagnosis. However, we have been observing a change in this pattern, especially in the last few years. We evaluated 104 patients, 77 females and 27 males aged 11-79 years (mean: 54.4 years), diagnosed between 1985 and 2002 at a University Hospital. Diagnosis was made on the basis of clinical findings and of high total and/or ionized calcium levels, high or inappropriate levels of intact parathyroid hormone and of surgical findings in 80 patients. Patients were divided into three groups, i.e., patients diagnosed from 1985 to 1989, patients diagnosed from 1990 to 1994, and patients diagnosed from 1995 to 2002. The number of new cases diagnosed/year increased from 1.8/year in the first group to 6.0/year in the second group and 8.1/year in the third group. The first group comprised 9 patients (mean serum calcium +/- SD, 13.6 +/- 1.6 mg/dl), 8 of them (88.8%) defined as symptomatic. The second group comprised 30 patients (mean calcium +/- SD, 12.2 +/- 1.63 mg/dl), 22 of them defined as symptomatic (73.3%). The third group contained 65 patients (mean calcium 11.7 +/- 1.1 mg/dl), 34 of them symptomatic (52.3%). Patients from the first group tended to be younger (mean +/- SD, 43.0 +/- 15 vs 55.1 +/- 14.4 and 55.7 +/- 17.3 years, respectively) and their mean serum calcium was significantly higher (P < 0.05). All of symptomatic patients independent of group had higher serum calcium levels (12.4 +/- 1.53 mg/dl, N = 64) than asymptomatic patients (11.4 +/- 1.0 mg/dl, N = 40). Our data showed an increase in the percentage of asymptomatic patients over the years in the number of primary hyperparathyroidism cases diagnosed. This finding may be due to an increased availability of diagnostic methods and/or to an increased awareness about the disease.


Sao Paulo Medical Journal | 2004

Head and neck hemangiopericytoma in a child: case report

Jomar Rezende Carvalho; Leonardo Haddad; Fernando Danelon Leonhardt; Marcilio Ferreira Marques Filho; Rodrigo Oliveira Santos; Onivaldo Cervantes; Márcio Abrahão

CONTEXT Hemangiopericytoma is a relatively rare tumor, first described in 1942, with approximately 300 cases described in the literature to date. In most cases, it affects the trunk and lower extremities. The head and neck incidence is less than 20%, mostly in adults. We describe a case of malignant head and neck hemangiopericytoma in a child. TYPE OF STUDY Case report. CASE REPORT A twelve-year-old male patient noted the presence of a firm painless right-side retroauricular lymph node of 1 cm in diameter, which at first remained unchanged for six months, but subsequently enlarged progressively. He denied having had previous trauma at that site. In November 2000, he presented nasal obstruction and voluminous epistaxis that required hospitalization and blood transfusion. During dental treatment one month later, a cranial x-ray revealed bone alterations. A subsequent computed tomography scan showed an extensive lesion of soft tissue density that had invaded the maxillary fossa, eroding the skull base and middle and nasal fossa. The child was then referred to our service, where biopsy was performed, giving a diagnosis of hemangiopericytoma. Shortly afterwards, magnetic resonance imaging revealed that this lesion had undergone significant growth, while maintaining the same invasion pattern. The patient was submitted to conservative surgery in April 2001, with only partial resection of the tumor because of its extent. Histopathological examination of the specimen confirmed the presence of malignant hemangiopericytoma. Following the surgery, the patient presented fast regrowth of the lesion, with partial response to chemotherapy and radiotherapy.


Journal of Osteoporosis | 2012

Total Parathyroidectomy with Presternal Intramuscular Autotransplantation in Renal Patients: A Prospective Study of 66 Patients

Rodrigo Oliveira Santos; Monique Nakayama Ohe; Aluizio B. Carvalho; Murilo Catafesta das Neves; Ilda Shizue Kunii; Marise Lazaretti-Castro; Márcio Abrahão; Onivaldo Cervantes; J. G. H. Vieira

Surgical treatment of secondary (SHPT) and tertiary hyperparathyroidism (THPT) may involve various surgical approaches. The aim of this paper was to evaluate presternal intramuscular autotransplantation of parathyroid tissue as a surgical option in SHPT and THPT treatment. 66 patients with renal chronic disease underwent surgery from April 2000 to April 2005 at Universidade Federal São Paulo, Brazil. There were 38 SHPT patients (24 women/14 men), mean age of 39.yrs (range: 14–58), and 28 THPT patients (14 women/14 men), mean age of 43.4 yrs (range: 24–62). Postoperative average followup was 42.9 months (range: 12–96). Postoperative intact PTH increased throughout followup from 73.5 pg/mL to 133 pg/mL on average from 1st to the 5th year, respectively, in SHPT and from 54.9 pg/mL to 94.7 pg/mL on average from 1st to 5th year, respectively, in THPT group. Definitive hypoparathyroidism was observed in 4 (6.06%) patients and graft-dependent recurrence in 6 (9.09%). Presternal intramuscular autotransplantation of parathyroid tissue is a feasible and safe surgical option in SHPT and THPT treatment.


Brazilian Journal of Medical and Biological Research | 2007

Analysis of the diagnostic presentation profile, parathyroidectomy indication and bone mineral density follow-up of Brazilian patients with primary hyperparathyroidism

Ulisses Maia de Oliveira; Monique Nakayama Ohe; Rodrigo Oliveira Santos; Onivaldo Cervantes; Márcio Abrahão; Marise Lazaretti-Castro; José Gilberto H. Vieira; Omar M. Hauache

Primary hyperparathyroidism is an endocrine disorder with variable clinical expression, frequently presenting as asymptomatic hypercalcemia in Western countries but still predominantly as a symptomatic disease in developing countries. The objective of this retrospective study was to describe the diagnostic presentation profile, parathyroidectomy indication and post-surgical bone mineral density follow-up of patients with primary hyperparathyroidism seen at a university hospital. We found 115 patients (92 women, median age 56 years) with primary hyperparathyroidism diagnosed during the last 20 years. We defined symptomatic patients based on the presence of any classical symptom affecting bone, kidney or the neuromuscular system. Surgical criteria followed the guidelines of the National Institutes of Health regarding asymptomatic primary hyperparathyroidism. Symptomatic patients and patients meeting surgical criteria for parathyroidectomy were 66 and 93% of the sample, respectively. Median calcium and parathyroid hormone values were 11.9 mg/dL and 189 pg/mL, respectively. After surgical treatment, 97% of patients were cured, with increases in bone mineral density of 19.4% in the lumbar spine and 15.7% in the femoral neck 3 years after surgery. Greater bone mass increases were detected in pre-menopausal women, men, and in symptomatic and younger patients, both in the lumbar spine and femoral neck. Our results support the previous findings of a predominantly symptomatic disease with a presentation profile that could be mainly related to a delayed diagnosis. Nevertheless, genetic and racial backgrounds, and nutritional factors such as calcium and vitamin D deficiency may play a role in the clinical presentation of primary hyperparathyroidism of Brazilian patients.


Arquivos Brasileiros De Endocrinologia E Metabologia | 2006

Utilidade da medida de PTH intra-operatório no tratamento cirúrgico do hiperparatiroidismo primário e secundário: análise de 109 casos

Monique Nakayama Ohe; Rodrigo Oliveira Santos; Ilda Shizue Kunii; Márcio Abrahão; Onivaldo Cervantes; Aluizio B. Carvalho; Marise Lazaretti-Castro; José Gilberto H. Vieira

INTRODUCAO: A medida de PTH intra-operatorio (PTH-IO) foi inicialmente descrita em 1988, sendo potencialmente util na definicao de sucesso apos a paratiroidectomia. OBJETIVOS: Avaliar prospectivamente perfil de decaimento do PTH-IO e sua capacidade de prever sucesso cirurgico no hiperparatiroidismo primario (HPP) e secundario a insuficiencia renal (HPS). PACIENTES E METODOS: 109 pacientes operados entre 06/2000 e 12/2004, sendo 33 HPP, 76 HPS (52 em dialise, 24 transplantados renais). PTH-IO: metodo imunometrico rapido (Elecsys-PTH/Immunoassay-Roche); tempo para resultado: 10 minutos. Coletas de sangue periferico nos tempos basal, 10 e 20 minutos pos-paratiroidectomia. RESULTADOS: HPP: queda media de PTH de 79,2% aos 10 minutos. HPS: queda media de PTH de 85,8% e 87,6% aos 10 minutos nos pacientes dialise e transplantados respectivamente. A cirurgia foi bem sucedida em todos, exceto em 2 pacientes (1 HPP, 1 HPS). Em ambos nao houve queda PTH-IO, sendo constatado adenoma duplo no HPP e paratiroide ectopica no HPS. CONCLUSAO: Medida PTH-IO fornece resultados confiaveis em tempo rapido, sendo capaz de discriminar persistencia da doenca se mantidos niveis elevados.


Brazilian Journal of Medical and Biological Research | 2003

Usefulness of a rapid immunometric assay for intraoperative parathyroid hormone measurements

Monique Nakayama Ohe; Rodrigo Oliveira Santos; Ilda Shizue Kunii; Aluizio B. Carvalho; Márcio Abrahão; Onivaldo Cervantes; Marise Lazaretti-Castro; José Gilberto H. Vieira

Intraoperative parathyroid hormone (IO-PTH) measurements have been proposed to improve operative success rates in primary, secondary and tertiary hyperparathyroidism (PHP, SHP and THP). Thirty-one patients requiring parathyroidectomy were evaluated retrospectively from June 2000 to January 2002. Sixteen had PHP, 7 SHP and 8 THP. Serum samples were taken at times 0 (before resection), 10, 20 and 30 min after resection of each abnormal parathyroid gland. Samples from 28 patients were frozen at -70 C for subsequent tests, whereas samples from three patients were tested while surgery was being performed. IO-PTH was measured using the Elecsys immunochemiluminometric assay (Roche, Mannheim, Germany). The time necessary to perform the assay was 9 min. All samples had a second measurement taken by a conventional immunofluorimetric method. We considered as cured patients who presented normocalcemia in PHP and THP, and normal levels of PTH in SHP one month after surgery and who remained in this condition throughout the follow-up of 1 to 20 months. When rapid PTH assay was compared with a routine immunofluorimetric assay, excellent correlation was observed (r = 0.959, P < 0.0001). IO-PTH measurement showed a rapid average decline of 78.8% in PTH 10 min after adenoma resection in PHP and all patients were cured. SHP patients had an average IO-PTH decrease of 89% 30 min after total parathyroidectomy and cure was observed in 85.7%. THP showed an average IO-PTH decrease of 91.9%, and cure was obtained in 87.5% of patients. IO-PTH can be a useful tool that might improve the rate of successful treatment of PHP, SHP and THP.


Arquivos Brasileiros De Endocrinologia E Metabologia | 2012

Parathyroid hormone: an early predictor of symptomatic hypocalcemia after total thyroidectomy

Felipe Augusto Brasileiro Vanderlei; José Gilberto H. Vieira; Flávio C. Hojaij; Onivaldo Cervantes; Ilda S. Kunii; Monique Nakayama Ohe; Rodrigo Oliveira Santos; Márcio Abrahão

OBJECTIVE The purpose of this study was to evaluate if the measurement of peri-operative parathyroid hormone (PTH) is able to identify patients with increased risk of developing symptoms of hypocalcemia. SUBJECTS AND METHODS Forty patients who underwent total thyroidectomy were studied prospectively. Ionized serum calcium and PTH were measured after induction of anesthesia, one hour (PTH1) and one day after surgery (PTH24). Patients were evaluated for symptoms of hypocalcemia and treated with calcium and vitamin D supplementation as necessary. RESULTS Symptomatic hypocalcemia developed in 16 patients. Symptomatic patients had significant lower PTH1 and greater drops in PTH levels. The selection of 12.1 ng/L as PTH1 level cutoff level divided patients with and without symptoms with 93.7% sensitivity and 91.6% specificity. The selection of 73.5% as the cutoff value for PTH decrease resulted in 91.6% sensitivity and 87.5% specificity. CONCLUSION PTH1 levels and the drop in PTH levels are reliable predictors of developing symptomatic hypocalcemia after total thyroidectomy.

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Márcio Abrahão

Federal University of São Paulo

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Rodrigo Oliveira Santos

Federal University of São Paulo

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Fernando Danelon Leonhardt

Federal University of São Paulo

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Geraldo Pereira Jotz

Universidade Luterana do Brasil

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José Gilberto H. Vieira

Federal University of São Paulo

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Leonardo Haddad

Federal University of São Paulo

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Marise Lazaretti-Castro

Federal University of São Paulo

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Monique Nakayama Ohe

Federal University of São Paulo

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Laurindo Moacir Sassi

Federal University of Paraná

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Murilo Catafesta das Neves

Federal University of São Paulo

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