Dados do Resumo

Título

Dosimetric analysis on microvascularized flaps in patients submitted to head and neck cancer treatment by Intensity-Modulated Radiation Therapy (IMRT)

Introdução

Microsurgical reconstruction is the gold standard used for the reconstruction of large tissue losses in the head and neck region caused by trauma and mainly by neoplasms, which are mostly located in the oral cavity and oropharynx. The free flap technique allows the removal of a large part of vascularized tissue from the donor area, thus allowing reconstructions in more complex cases, with a success rate above 90%. The most commonly used flaps are: musculocutaneous thigh flap and ostemusculocutaneous fibula flap.

Objetivo

The present study evaluates the complications and tolerated doses of adjuvant RT using the IMRT technique in patients treated for oral cavity and oropharyngeal cancer who underwent surgery and underwent microsurgical reconstruction using microvascularized free flaps.

Métodos

The Chi-Square test was applied to detect differences between groups. To compare qualitative variables in relation to the distribution of quantitative variables, the Mann-Whitney non-parametric test was used, and also the Kruskal-Wallis non-parametric test, when appropriate. Logistic regression models were used to evaluate possible risk factors for the outcomes. The significance level adopted will be 5%. Statistical analyzes were performed using SPSS version 25 software.

Resultados

In this study of 72 patients, 41 (56.9%) belong to Group A, 17 (23.6%) belong to Group B and 14 (19.4%) belong to Group C. As complications we observed that 3 (12%)) presented plaque exposure, 5 (20%) fistula, 4 (16%) infection, 6 (24%) osteoradionecrosis, predominantly in Group A (4 (25%).

Conclusões

No statistically significant differences were found between the appearance of complications between irradiated and non-irradiated patients (p= 0.489), as well as the use of different types of flaps. Regarding dosimetry, radiotherapy has no impact on total dose (p= 0.237), maximum dose (p=0.291) and minimum dose (p= 0.132), were not associated with the appearance of complications. On the other hand, the average doses received by the flaps, showed a statistically significant trend to be associated (p=0.065) with the emergence of complications, indicating that for every 1Gy increase in the average dose, the chance of complications in the flap increases 0.68 times.

Palavras Chave

Intensity-Modulated Rdaiotherapy; reconstructive surgical procedures; Head and Neck Cancer