Objective assessment of trismus in oral and oropharyngeal cancer patients treated with intensity-modulated radiation therapy (IMRT).

PURPOSE: The aim of this study was to estimate the prevalence of trismus in oral and oropharyngeal cancer patients (OOPC) treated with intensity-modulated radiation therapy (IMRT) and to identify the role of risk factors in patients who developed trismus. MATERIALS AND METHODS: A retrospective cohort study of OOPC treated with IMRT in our institution from 2009 to 2014 was performed. Patients eligible for this study had pre-RT and post-RT maximal inter-incisal opening (MIO) measurements at 6-48 months post-RT, treated with high-dose radiation (≥60 Gy) and pre-RT MIO ≥36 mm. A descriptive analysis to identify the incidence of trismus, with trismus stated as MIO ≤35 mm at or after 6 months post-RT measurement was performed. The role of risk factors such as age, gender, tumor site, tumor size (T), tumor stage, pre-RT MIO measurements and radiation dose to the tumor were assessed using Fisher exact test and the radiation doses to the ipsilateral muscles of mastication in patients who developed trismus were assessed by matching with control (non-trismus) patients using Wilcoxon Signed Rank test. RESULTS: The study consisted of 54 patients with a median age of 55 years and 81% were males. The median follow-up time was 10 months. The prevalence of trismus was 14.8%. Patients with pre-RT MIO measurements ≤40 mm were at risk of developing trismus (P < 0.001). In trismus patients, the average mean radiation dose to the masseter and medial pterygoid muscles was numerically higher but not significantly different (P = 0.08; P = 0.22, respectively) to matched control patients. Age, gender, radiation dose to the tumor, tumor site, size (T) and stage were also found to be not significant. CONCLUSION: Pre-RT MIO measurement was a significant risk factor for the development of trismus. However, this is a non-modifiable factor. Limiting radiation dose to the muscles of mastication could prevent this complication.

Primary Ewing Family of Tumors of the Jaw Has a Better Prognosis Compared to Tumors of Extragnathic Sites.

PURPOSE: Primary Ewing sarcoma of the jaw is rare. The aim of this study was to describe new cases of primary Ewing sarcoma of the jaw and investigate reported prognostic factors of Ewing sarcoma in this series and treatment outcome. MATERIALS AND METHODS: Six patients with primary Ewing sarcoma of the jaw were treated at the Memorial Sloan Kettering Cancer Center (MSKCC) from 1992 through 2013. Clinical data, pathology reports, treatment prescribed, treatment regimens, outcome, and follow-up information were reviewed. RESULTS: Five of 6 patients were female and 5 cases were in the mandible. No patient presented with metastatic disease at diagnosis. All cases were positive for CD99, and 3 patients with genetic confirmation were positive for EWS-FLI1 fusion or EWSR1 gene rearrangement. All patients received induction multiagent chemotherapy and surgical resection and 2 patients received adjuvant radiotherapy. Total (grade IV) or nearly total (grade III) tumor necrosis in 3 of 5 patients (60%) assessed for histologic response to chemotherapy indicated intense sensitivity. All patients were alive and free of disease, with no history of local recurrence, at a median follow-up period of 6.5 years. CONCLUSION: Patients with primary Ewing sarcoma of the jaw have a good prognosis and metastasis is an uncommon occurrence at initial presentation.