Objective: Tumours originating from jugular bulb, carotid bifurcation, Vagus nerve are collectively called Paragangliomas. They are slow growing, essentially benign tumours, but can be detrimental if untreated. There is limited evidence on the effectiveness of fractionated radiotherapy in the management ofs Glomus jugulare tumours. The aim of this study is to determine the efficacy of Linear accelerator based fractionated external beam radiotherapy on unilateral inoperable Glomus jugulare paragangliomas. Method: This is a retrospective analysis of all the 12 cases of inoperable, unilateral Glomus jugulare tumours treated during the period 2011-2016 at a tertiary cancer centre in Kenya. Minimum follow up duration was 3 years. Patient characteristics, disease staging, immediate complications and therapeutic efficacy were analysed from the case files. Results: The 12 patients diagnosed with inoperable Glomus jugulare tumours reported in this period were treated with external beam radiotherapy to a tumour dose of 54 Gy in 30 fractions over a period of 6 weeks using IMRT technique in 6 MV Linear accelerator. 2/3rd of the patients were females in 5th and 6th decade of life. Onset of first symptom to initiation of treatment was found to be 1.7 years. Headache, earache, and tinnitus were the main complaints. No major side effects were recorded during therapy. Mean length of the tumour in its maximum dimension at the time of diagnosis was 4.5 cm. At the end of one-year post therapy, a mean reduction of 6.5 mm in the tumour length was observed, (Range: 0 - 15 mm). Tumour size remained static for a year and thereafter a slow growth pattern of 1mm per year was observed. Conclusion: Fractionated external beam radiotherapy is an effective and non-invasive treatment for advanced, inoperable Glomus jugulare paragangliomas. Clinical stability through tumour control was observed. Though newer radiation techniques like Cyberknife, Proton therapy offer better tumour control, conventional external beam radiotherapy is an effective tool in disease containment in resource limited countries.
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