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Squamous cell carcinoma of the external ear is rare and the combination of external beam radiotherapy and brachytherapy has been beneficial for tumors in this location due to the advantage of organ preservation and thereby cosmesis. The incorporation of brachytherapy allows the delivery of doses large enough for the eradication of tumor and the advantage of rapid dose fall off due to brachytherapy minimizes the radiation damage to the nearby organs at risk. Herein we report a case of elderly male with early stage squamous cell carcinoma of external ear treated with a combination of external beam radiation with brachytherapy. An eighty nine year old male reported to our hospital with the complaints of left sided ear ache the presence of some mass in the left external ear. A diagnostic Contrast enhanced Computed Tomography (CECT) scan of head and neck showed a 1.6*1.5*1.4 cm mass lesion (maximum diameter) involving anterior cartilaginous part of left external auditory canal and preauricular soft tissue,thereby staged as T2N0,stage II. Patient was planned for External Beam Radiotherapy (EBRT) using 3D CRT(Conformal Radiotherapy) technique by 6 MV photon beam to a dose of 50 Gy in 25 fractions (2 Gy/#) and following this,a gap of seven days was given and after that four fractions of HDR brachytherapy using Iridium 192 of 3 Gy/# keeping a gap of six hours between two fractions on a single day,Two flexible plastic tubes were used for radiation delivery. The size of the catheter used for radiation delivery was 6 French. Planning CT scan was taken and target volume defined as PTV and a dose of 3 Gy per fraction to a total of 4 fractions was prescribed to the target volume. The spike of intravenous site was used for fixing the plastic tube in the mould. The tumor responded ver well to radiotherapy. Brachytherapy is an effective modality to boost high risk areas without significant damage to the surrounding area. External Beam Radiotherapy in case of early stage carcinoma external auditory canal combined with brachytherapy boost can be considered as a better modality with less severe side effects and better cosmesis. [ABSTRACT FROM AUTHOR]

Background: Evaluation of a HDR- interstitial brachytherapy plan is a challenging job. Owing to the complexities and diversity of the normalization and optimization techniques involved, a simple objective assessment of these plans is required. This can improve the radiation dose coverage of the tumour with decreased organ toxicity.Aim: To study and document the various dose volume indices and parameters required to evaluate a HDR interstitial brachytherapy plan by Volume normalization and graphical optimization using MUPIT (Martinez Universal Perineal Interstitial Template) in patients of carcinoma cervix.Settings and Design: Single arm, retrospective study.Methods and Materials: 35 patients of carcinoma cervix who received EBRT and HDR brachytherapy using MUPIT, were selected. The dose prescribed was 4 Gray/Fraction in four fractions (16Gy/4) treated twice daily, at least 6 hours apart. CTV and OARs were delineated on the axial CT image set. Volume normalization and graphical optimization was done for planning. Coverage Index (CI), Dose homogeneity index (DHI), Overdose index (OI), Dose non-uniformity ratio (DNR), Conformity Index (COIN) and dose volume parameters i.e. D2cc, D1cc, D0.1cc of rectum and bladder were evaluated.Statistical Analysis: SPSS version 16 was used.Results and Conclusion: CI was 0.95 ± 1.84 which means 95% of the target received 100% of the prescribed dose. The mean COIN was 0.841 ± 0.06 and DHI was 0.502 ± 0.11. D2cc rectum and bladder was 3.40 ± 0.56 and 2.95 ± 0.62 respectively which was within the tolerance limit of this organs. There should be an optimum balance between these indices for improving the quality of the implant and to yield maximum clinical benefit out of it, keeping the dose to the OARs in limit. Dose optimization should be carefully monitered and an institutional protocol should be devised for the acceptability criteria of these plans. [ABSTRACT FROM AUTHOR]