Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_30_библиотеки_им_акад_М_И_Перельмана

The decision needs to be made in a multidisci­plinary clinical team. Para-nasal sinus malignan­cies are rare aggressive tumors. Radiotherapy is an integral part of management either as single modality or in combination. There is wide range of histo-pathological entities in this subtype with varying radiation sensitivity. Local failure is the major pattern of relapse. Lymph nodal involve­ment is less frequent in nasal and para-nasal sinus malignancies although in cases of nasopharyngeal cancers it is present in up-to 90 % of the cases. Advent of advanced technologies in the form of IMRT and particle therapy substantially improved the clinical outcome. Conformal treatment pro­vides high rates of local control with decreased toxicities. Margin positivity & extra-capsular spread in Lymph nodes are the indication for che­motherapy. Chronic rhinosinusitis negatively affects quality of life (QoL) by disturbing the physical, social, and emotional well-being of patients. It also reduces economic productivity and can increase the risk of depression and sleep dysfunction. EuroQol 5D, Rhinosinusitis out­come measures (RSOM), McGill Pain Questionnaire, Short Form-36 Health Survey and Short Form-12 Health Survey Rhinosinusitis Disability Index, Chronic Sinusitis Survey Score, Sinonasal Outcome Test-20, -16, and -22 are the scoring systems used to assess the quality of life.

Radiation can be delivered by external beam radiotherapy, brachytherapy, or a combination of both. In a study by Allen etal. [1], 32 patients with nasal cavity tumors were treated by a median EBRT dose of radiation of 65Gy. At a median follow-up of 11years, 5-year locoregional control

Surgery followed by postoperative radiation ther­apy (PORT) is the mainstay of treatment in advanced paranasal sinus tumors. Other indica­tions of PORT include high tumor grade or high­risk histology, perineural invasion, lymphovascular space invasion, positive lymph nodes, margin positivity, and inadequate resec­tion or tumor spillage. Radical radiotherapy with chemotherapy is used inlocally advanced T3, T4 tumors especially in ethmoid sinus tumors where extensive surgery may lead to structural and functional decit. Patients who are not t for sur­gery due to medical comorbidities are also candi­dates for radiotherapy. In cases of borderline resectable tumors with anterior soft tissue or skin inltration, minimal preorbital invasion or ptery­gopalatine invasion preoperative radiation is indi­cated [3, 4].

Meticulous radiotherapy planning is very crucial to achieve higher control rates. MRI of the naso­pharynx and neck is an important diagnostic investigation and is very useful for radiation planning as clivus and nerves are best seen on MRI.Figure10.2 shows the various steps of radi- ation therapy workow from preplanning to delivery of radiation. Target volume delineation involves contouring of tumor volumes and organs at risk. Gross tumor volume (GTV) consists of the entire visible gross tumor clinically or radio­logically. Clinical target volume (CTV) encom­passes GTV, postoperative bed in cases of postoperative cases, regions of positive margin, and regions with nodal extracapsular extension and regions at higher risk of micrometastasis. A 3–5mm margin is given to CTV to account for inter- and intrafraction set-up errors to create a planning target volume (PTV) [6, 7].

tumor volume along with a 50–60Gy to the areas of micrometastasis. In cases of pre-op RT where debulking is the primary aim, an RT dose of 50Gy/25# is given. There are different fraction­ation schedules for palliative RT ranging from 8Gy in a single fraction to 30Gy in 10 fractions. 20Gy over 5 fractions is one of the commonly followed palliative dose fractionations.