Specically, in patients with head and neck cancer, radiotherapy can be employed in all subsets and clinical stages. In initial tumors, it is used as a single therapeutic modality, with results similar to those obtained with surgery. It may also be used as an adjuvant treatment to surgery in patients who present with predictors that indi­cate a high risk for locoregional recurrence (lymph node involvement, positive mar­gins, locally advanced disease with adjacent extension, etc.). In addition, in recent years there has been increasing interest in the use of radiotherapy in combination with chemotherapy in organ preservation protocols, without detrimental effects on survival and providing organ preservation. Finally, radiotherapy can be used alone or in combination with chemotherapy in patients with unresectable or nonsurgical tumors due to comorbidities, and also has an important role as palliative treatment in the relief of local pain, bleeding, and/or imminent obstruction of the airway.

With the emergence of three-dimensional (3D) techniques and imaging acquisi­tion using computed tomography (CT) scans and magnetic resonance, as well as positron emission tomography (PET)CT, it was possible to specically delineate the areas of interest to be treated, as well as adjacent healthy organs (salivary glands, medulla, spinal cord, healthy segments of the oral cavity, nontumoral larynx, swal­lowing musculature, among others) in order to report and constrain the dosage delivered to each of these volumes. This technique is called conformational radio- therapy and, with it, a better conformation of the treatment dose begins to occur. However, only with the advent of important radiotherapy accessories, such as the multileaf collimator and specic software, it has been possible to modulate the intensity of the treatment beam and, consequently, to intensify the dose designated for the tumor volume and to perform differentiated escalating dosages between tumor regions and potential healthy volumes, consequently increasing the protec­tion of healthy tissues. This technique is called intensity-modulated radiotherapy (IMRT). Improvements in this technique have been made possible by rotational arcs, meaning that the radiation beam is delivered by a rotating arc performed by the head device and concurrent uency energy, that allows beam modulation and results in a complex delivery system wich can provide IMRT dinamically, with the rotation of the entire device. This approach also allows to decrease the total time in active beam, so it’s good for departmental expedience and improves device wear. This technique is called radiotherapy with dynamic arc modulation, or a modulated dynamic arc. It is important to note that regardless of the technique used (conven­tional, conformational, IMRT, or dynamic arc), radiotherapy offers good rates of local control and survival. What will actually vary will be the frequency and inten­sity of early and late side effects of treatment [4–8].

tomy before starting radiotherapy, leaving the tumor lesion intact;

from surgery at other tumor sites (thyroid, pharynx, or trachea) and who have

clinical, radiological, and/or pathological predictors that indicate a high risk of

locoregional recurrence, with consequent indication of adjuvant radiotherapy;

(examples are total glossectomy or tongue brachytherapy), with a need for tra-

Eventually, patients with laryngeal and/or hypopharyngeal tumors present with sig­nicant airway involvement, requiring a tracheostomy prior to radiotherapy. In addi­tion, laryngeal edema induced by radiotherapy may reduce the already compromised airway and could precipitate a surgical intervention with emergency tracheostomy. In this context, pretreatment tracheostomy has been associated with lower overall survival

among patients undergoing surgery for transglottic tumors [13]. Such evidence also exists for patients treated with radiotherapy, since several studies have clearly dem­onstrated the prognostic importance of tracheostomy as a predictor of worse local control, worse disease-free survival, and worse overall survival in patients who are irradiated [14–16]. A prospective study conducted at INCA included 49 patients with locally advanced laryngeal tumors treated with radiochemotherapy. Of the 49 patients recruited, 12 patients (24.5%) underwent tracheostomy prior to initiation, and these patients had worse progression-free survival (hazard ratio [HR] 2.83, 95% con­dence interval [CI] 1.61–4.89, p < 0.001), worse median survival (12 versus 56months, HR 2.37, 95% CI 1.43–3.93, p<0.001) and worse overall survival at 3years (6% versus 61%, p=0.001) than patients without tracheostomy [17].

Another study conducted by the Toronto Sunnybrook Regional Cancer Center [19], with 270 patients, demonstrated that patients without tracheostomy had 74% 2-year disease-free survival, while tracheostomized patients had a 2-year disease- free survival rate of 41%. Although more evident in glottic tumors (78% versus 32%), this difference was also found in supraglottic tumors (64% versus 47%). Regarding local control, there was also a difference: it was achieved in 94% and 81% of patients with glottic and supraglottic tumors without tracheostomy, respectively, and in 69% and 80% of those with glottic and supraglottic tumors with tracheostomy, respectively. A fundamental counterpoint to be made, however, is that the clearly worse results obtained in such patients leads to the misperception that radiochemotherapy is unlikely to be able to preserve the larynx in a patient with compromised airways. This has motivated some centers to even consider pretreatment tracheostomy as a formal indi­cation for primary laryngectomy. The Canadian series published by the Toronto Sunnybrook Regional Cancer Center demysties this issue. In this study, preservation of the larynx was feasible in more than 40% of patients treated with radiotherapy who underwent pretreatment tracheostomy, without compromising the cause-specic sur­vival. The authors of the aforementioned study also emphasized that the need for tra­cheostomy should not be ruled out or considered a formal contraindication to conservative treatment with radiochemotherapy, but it makes a realistic and judicious assessment of the success of laryngeal preservation therapy mandatory and funda­mental in these patients with unfavorable clinical presentation [19].