Dados do Trabalho

Título

Incidence and predictive factors for Osteoradionecrosis lesions in patients with Head and Neck Cancer submitted to Intensity Modulated Radiation Therapy (IMRT)

Introdução

Osteoradionecrosis (ORN) of the jaws is a late, severe, and difficult to manage side effect in patients who underwent Radiotherapy (RT) in the head and neck region. Regarding its relationship with RT, it is primarily associated with the total dose delivered, technique and the target volume irradiated; and patient-related factors, such as the use of tobacco/alcohol, oral hygiene, tooth extractions, comorbidities, and possible systemic disorders. However, few studies have described these predictive factors that could act as potential predictors of further occurrence of ORN.

Objetivo

The present study aims to evaluate the incidence and to establish the potential predictive factors for the onset, development, and progression of ORN lesions in patients with head and neck cancer who underwent RT through the IMRT technique at the A.C. Camargo Cancer Center during 2006-2020.

Métodos

After an observational, descriptive, and retrospective analysis of electronic medical records, 1046 patients were found in initial research in our institutional database RECRUIT and a primary analysis of the data was performed based on the inclusion and exclusion criteria. Thus, 247 patients were retrieved, and two groups were composed: a) Patients submitted to IMRT technique with or not ORN lesions in the jawbones and b) Patients submitted to other RT techniques with or not ORN lesions. Demographic, clinical, and therapeutical data were collected, and regarding RT techniques, statistical association was established between them and ORN onset by Chi-Square test with p value lower than 0,05. The predictive factors associated were established by COX-regression in the multivariate analysis .

Resultados

Two-hundred and forty-seven patients were included and 143 patients (58,4%) for Group A and 102 (41,6%) belong to Group B. Most of them were men (73.3%) and 23.9%, female. Regarding the histological subtype for primary tumor, Squamous Cell Carcinoma (SCC) was the most frequent (87.6%) diagnosed, after Mucoepidermoid and Adenoid Cystic Carcinoma of salivary glands. On the other hand, surgery was performed in full patients (99%) , RT (100%) and Chemotherapy (CHT) in 142 patients (62.6%). For the surgical technique to manage primary tumor, marginal osteotomy was performed in 34 patients (50%) and segmental (50%) in other 34.Thus, IMRT was applied to 143 patients (58.4%), 3D conformal in 95 (38.8%) and 2D in 7 (2.9%). ORN lesions were diagnosed in 46 patients (18.6%) who undergone RT and it was observed in the mandible(84.4%), maxilla (11.1%) and both jawbones (2.2%). After Chi-square test, statistical association was established between RT technique used for primary tumor management and the onset of ORN as later side-effect of RT with a p value of 0.001.

Conclusões

The pathophysiology of ORN continues to be controversial and the potential predictive factors for its occurrence, development and progression are still unclear. Marginal mandibulectomy performed as primary surgical technique should be evaluated in order to clarify its role as potential risk factor of occurrence of this condition in patients that will undergo RT. The incidence of ORN lesions in our population was directly associated with RT technique used for primary tumor management, and IMRT showed lower cases when compared with other techniques.

Palavras-chave

Osteoradionecrosis; Intensity-Modulated Radiotherapy; Head and Neck Neoplasms

Financiador do resumo

This work was supported by the National Council for Scientific and Technological Development of Brazil (140071/2019-9). The author VBF and WEB-P were student fellows and supported with a scholarship provided by the National Council for Scientific and Technological Development of Brazil (CNPq). Regarding the ethical concerns, the number protocol was 5.120.349/ 3053/21 approved by our Institutional Committee from A.C. Camargo Cancer Center, Sao Paulo, Brazil.