Radiotherapy in parotid carcinoma – literature review
- Lalova, V. Parvanova, K. Popov, I. Gergov, D. Katsarov, B. Krastev
This paper review the indications of postoperative radiotherapy of the cancer of parotid gland and the anatomical and histological factors determining the results. The variety of histological subtypes, the degree of malignancy, the presence of lymphovascular (LVI) or perineural (PNI) invasion, combined with the TN stage, make it difficult to determine the radiotherapy indications and its contribution to local control, distant metastasis and overall survival. Surgical treatment is a standard method for localized carcinomas but in 5 to 40% оf patients found local recurrence to 5 years after surgery, mostly around the facial nerve, the R1 resection line or around the metastatic lymph nodes (N +) with extracapsule involvement – high risk group. The degree of malignancy – G3 correlates in 50% of the patients with lymph node involvemеnt, as well as the presence of adenoid cyst, mucoepidermoid, epidermoid or undifferentiated carcinomas. DM was observed in 20% of patients with an average survival of 43 to 73 months. The rule of practice for prescribing adjuvant treatment for tumors > 4 cm, ie. T3–T4 carcinomas. The relative risk for local recurrence after operation or postoperative radiotherapy is 9.7 to 2.3. In high-risk patients adjuvant radiotherapy has a statistically significant contribution to overall survival, whereas in patients with moderate risk tumors <4 cm, the influence of histological factors, G3, LVI, PNI, in conjunction with the TN-stage is studied.
Key words: CARCINOMA OF THE PAROTID GLAND. RADIOTHERAPY