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Introduction: In radiotherapy treatment of head and neck (H&N) cancers, more complex quality assurance checks and patient-specific dosimetry are required to ensure accuracy in modern technology. In this paper, a new cost-effective human tissue equivalent H&N phantom was designed to serve as an economical and adaptable tool for assessment and assurance of precise radiotherapy dose delivery. Material and Methods: The phantom was designed using locally available paraffin wax and tissueequivalent materials. Computed tomography (CT) images of the phantom were acquired using a conventional CT simulator and were registered with the images of a real patient having approximately similar physical dimensions. The geometric and attenuation properties of the structures in the phantom were studied and compared to the structures of the real patient. Results: Hounsfield unit (HU) values of different structures of the phantom were compared to the values obtained from the CT images of a real patient and were found to be in good agreement. HU values obtained for the right, and left eye, brain, larynx, and bone shell were 7(±10) HU, 6(±9), 30(±14) HU, -984(±6) HU and 873(±214) HU in phantom. Structures simulated in phantom agreed well on comparison regarding both their design and radiation properties with respect to real patient human tissues. Gamma analysis was performed for the axial dose plane at plan isocenter for both the calculated dose distribution in H&N phantom and the patient agrees for 98.79% passing rate for 3%/3mm criteria. Conclusion: The designed phantom depicts human anatomy and meets the requirements of tissue equivalence. The result shows that phantom has proved to be a cost-effective and valuable tool for accurate verification of dose distributions in regions of clinical and dosimetric interests. [ABSTRACT FROM AUTHOR]

Introduction: Urinary bladder cancer is a major cause of morbidity and mortality worldwide. As per the data from the US cancer registry, it was diagnosed in nearly 71,000 patients and led to 14000 deaths in 2013. The Indian data in this regard are lacking with few case reports and epidemiological data only. The paucity of treatment data in this regard led us to undertake this prospective study at our radiation oncology canter. Carcinoma urinary bladder is a heterogeneous disease with variable natural history. Male preponderance and association with cigarette smoking appears to be the foremost in natural history of the disease. Our data analyzed the management of muscle-invasive medically and surgically inoperable carcinoma urinary bladder in a resource constraint setting at a tertiary care center by bladder preservation protocol (BPP). Materials and Methods: This prospective study was aimed to evaluate the treatment outcome in surgically inoperable muscle-invasive carcinoma urinary bladder in a resource constraint setting at a tertiary care center by BPP. All patients were treated with telecobalt 60 machine up to a dose of 60--66 Gy along with concurrent chemotherapy. Interim assessment was done at 40 Gy. Results: A total of nine patients were taken up for treatment with BPP. All patients were evaluated with standard evaluation protocol. All patients were followed up till any event occurred and till 6 years. Out of nine patients treated, six patients are still alive without any progression of disease and are disease free with standard evaluation on follow-up. Two patients died during the 1st year of follow-up. One patient progressed with lung and abdominal metastases 5 months after the completion of treatment and one patient was lost to follow-up. Conclusion: BPP using trimodality therapy is a suitable alternative to radical cystectomy in medically and surgically inoperable carcinoma urinary bladder. These patients should be highly compliant for regular follow-up, and acute and long-term toxicity should be evaluated in detail at each visit. BPP gives a ray of hope in such settings and should be done with caution. In our study, we treated all these patients in our resource constraint settings with good results and high survival rates. Our integrated team of radiation oncologists, medical oncologists, and urologists closely followed up these patients in order to optimize outcomes. [ABSTRACT FROM AUTHOR]