Tangential Film Verification for Lung Volume Involvement in Breast Cancer Radiation Treatment: East Coast Malaysia Experience

Post mastectomy or lumpectomy irradiation of the chest wall or breast is common practice to minimize the local recurrences. Chest wall irradiation is a complicated technical procedure as the pathological target volume involves the normal structures like lung, heart, and head of humerus, esophagus and trachea known as organ at risk. The aim of this study was to verify the cases of the conventional tangential field technique among the breast cancer patients from year 2006 to 2011. In this study, the previous data of breast cancer patients treated with radiation from 2006 to 2011 were evaluated. Conventional 2D planning was done by taking body contour of the patient. Tangential verification films were taken in patients where excess of lung volume was suspected. The data was analyzed to verify the real lung volume irradiated. From a total 112 patients underwent tangential verification films during that period, 33% of patients underwent breast conservative surgery (BCS) while the rest underwent mastectomy. The depth of the field from the skin to 90% isodose ranges from 2.0 to 8.0 cm. However, 15 (13.4%) out 112 patients needed a replanning. As a conclusion, from 112 cases, the numbers of re-plan cases for year 2006 to 2011 were only 13 (11.61%) which is less than 15%. This result can be used by the centre who no dot have the facilities for simulation to verify the depth dose in 2D planning

Modified Harrington Procedure for Acetabular Insuficiency Due to Metastatic Malignant Disease

Extensive peri-acetabular osteolysis caused by malignant disease process is a major surgical challenge as conventional hip arthroplasty is not adequate. We describe a modified use of the Harrington procedure for acetabular insufficiency secondary to metastatic disease in twelve patients. The procedures include application of multiple threaded pins to bridge the acetabular columns, anti-protrusio cage and cemented acetabular cup. Eleven patients were able to walk pain free and achieved a mean Musculoskeletal Tumour Society Functional Score of 80 (range, 68 to 86)

Evaluation of organ at risk (OAR) doses based on 2D treatment planning in intracavitary brachytherapy of cervical cancer

Conventional two-dimensional (2D) treatment planning of intracavitary brachytherapy is still a common practice at the radiotherapy center. The purpose of this study was to evaluate the organ at risk (OAR) doses estimated based on International Commission on Radiation Units and Measurements (ICRU) reference-point in patients with cervical cancer treated with high-dose-rate (HDR) intracavitary brachytherapy (ICBT). Between January 2010 and April 2014, 21 cervical cancer patients were treated with 42 fractions of brachytherapy using tandem and ovoids and underwent post-implant two-dimensional (2D) radiograph scans. HDR brachytherapy was delivered to a dose of 18 Gy in two fractions. Using the Oncentra brachytherapy treatment planning system (BTPS) software version 4.1 (Nucletron, Netherlands), the bladder and rectum points were retrospectively reconstructed based on 42 orthogonal radiographs datasets. The ICRU bladder and rectum point doses were recorded. As for results, the mean percentage dose of rectum and bladder for selected patients treated with intracavitary brachytherapy treatment (ICBT) were 47.27 and 75.59%, respectively. Combinations of ovoid’s size, length of tandem and anatomy variation between each patient were factors that affected the dose to the OAR. Therefore, the ICRU reference points can still be used with the 2D brachytherapy treatment planning in evaluating the OAR doses