‘Inverted Y’ field radiotherapy planning with multi-leaf collimator: A single isocentric technique using multiple fields

The purpose of our study is to describe a planning technique using multi-leaf collimator and asymmetric fields for irradiating an ‘inverted Y’ shaped geometry in a patient with testicular seminoma. The entire target area covering the para-aortic, pelvic, and inguinal nodal regions was split into three fields. Single isocenter half-beam block technique was employed. The fields were planned with antero-posterior and postero-anterior portals with a differential weightage. The dose was prescribed at the respective reference points of the fields. A uniform dose distribution for the entire portal was achieved without any under- or over-dosing at the field junctions.

Morbidity Patterns in Oncology Patients at FMRI, Gurgaon:A Hospital Based Study at a New Tertiary Care Institute

Objective: This study aims to analyze the patterns of morbidity amongst cancer patients attending a tertiary care hospital.Materials and Methods: Data were collected from various departments dealing in cancer care. Patient’s data were categorized according to diagnosis and place of residence.Results: A total of 1490 new cancer patients were registered. Out of these 1140 were Indians from 22 different states {males= 609 (53.4%) and females= 531 (46.6%)} and remaining 350 patients were from 27 different countries {males= 223 (63.7%) and females=127 (36.3%)}. The five most common cancer site groups amongst all males (n=832) were digestive organs (18.6%) followed by lymphoid, hematopoietic and related tissue (16.8%);  respiratory intrathoracic organs (14.1%); then eye, brain and other parts of central nervous system (11.4%) and lip, oral cavity and  pharynx (9.5%)  and in all females (n=658) the most common cancer site were breast (31.5%) followed by  genital organs (17.3%); digestive organs (11.2%); lymphoid, hematopoietic and related tissue (9.3%) and eye, brain and other parts of nervous system (9.0%).Conclusions:  The present study highlights the pattern of cancer among patients in a corporate tertiary health care institute. There is therefore an inherent bias, the leading sites of malignancies amongst Indian males and females varied from that in the Western population; this could be attributed to various cultural, environmental factors, life style, genetic factors etc. in different regions of India and different nations of the world.

Validation of an integrated patient positioning system: Exactrac and iViewGT on Synergy Platform

Purpose: Evaluation of the newly integrated system for its validation and designing a quality assurance frame work to assess its geometrical, radiological and mechanical accuracy.Methods: Isocentric accuracy of two independent imaging modalities, kV based ExacTrac and MV based iViewGT was evaluated using Winston-Lutz test. A pelvic humanoid phantom was used for the radiological end-to-end test for its clinical utilization. Image quality for the systems was evaluated using Las Vegas Phantom and ETR-1 plate. The kV system was also assessed for kVp accuracy, kVp - dose linearity, mAs-dose linearity and timer linearity and its accuracy. The system was tested for total filtration and output consistency. Tests for uniformity and noise measurement of kVp accuracy and its reproducibility, linearity test between applied kVp and the x-ray dose, linearity Test between applied mAs and the x-ray dose were also done. Results: Winston-Lutz test gave the isocentric deviation of 0.058 ± 0.015 mm with the average lateral deviation as 0.028 ± 0.021 mm, average longitudinal deviation as 0.032 ± 0.015 mm and average vertical deviation as 0.030 ± 0.016 mm. With the phantom test, the minimum measured displacement of Exactrac positioning was 0.2 ± 0.3 mm, 0.0 ± 0.2 mm and 0.1 ± 0.3 mm in longitudinal, lateral and vertical directions respectively. In image quality test, visible smallest visible hole size seen by both Exactrac and EPID imaging system was 5 mm and can resolve 1.5 lp/mm or better. The image uniformity was found to be 132.9 ± 3.06 pixels for MV images and 139 ± 4.41 pixels for kV images with the associated noise of ≤1% both for 120 kV-20 mAs and 4 MV beam energy of ExacTrac and iViewGT respectively. The uniformity and noise test, measured pixel intensity values for various points on MV and kV images separately were found to agree within ± 1% with respect to the central axis pixel value. The kVp accuracy and its reproducibility were tested for kV imager only. The deviation of kVp was found to be than ± 1% and its precision was seen to be even lesser than ± 0.1%. Linearity test between applied kVp and the x-ray dose and applied mAs and x-ray dose were tested only for the ExacTrac. Both the coefficient of linearity for kVp as well as mAs was found to be < 0.1. Conclusion: It is feasible to install ExacTrac imaging system with an Elekta linear accelerator. Both the imaging systems were found to be compatible in terms of image quality test and isocentric accuracy and can be used for the patient imaging in the same Linear accelerator.-----------------------------Cite this article as: Jassal K, Munshi A, Sarkar B, Paul S, Sharma A, Mohanti BK, Ganesh T, Chougule A, Sachdev K. Validation of an integrated patient positioning system: Exactrac and iViewGT on Synergy Platform. Int J Cancer Ther Oncol 2014; 2(2):020212. DOI: 10.14319/ijcto.0202.1

Radiation injury to the spinal cord in head and neck cancers: Does field arrangement have a role

Study Design: A study of eight cases of head and neck cancers, to see if the cord was getting a higher dose in the antero-posterior (A-P) fields, compared to the bilateral(B/L) fields. Objective: Radiation damage to the spinal cord is a critical issue for the radiation oncologists. This study was conducted to evaluate, if the dose to the spinal cord is higher by the antero-posterior (A-P) fields, compared to the bilateral(B/L) fields. Materials and Methods: Eight cases of head and neck cancer were taken in our study. Two beam arrangements were placed in the treatment planning system, the B/L and the A-P fields. The DVH's for the cord dose were recorded and compared in both plans, with a standard fraction size of 200cGy/fraction. Results: The mean dose to the spinal cord was 168.06cGy in A-P arrangement, while it was 133.75cGy in the B/L arrangement. Conclusion: A-P field arrangement in head and neck malignancies delivers a higher dose to the spinal cord. Therefore, we need to spare the cord at an earlier dose limit

Congenital peripheral primitive neuroectodermal tumor: A case treated successfully with multimodality treatment

Neonatal tumors comprise less than two percent of childhood malignancies. Most are solid tumors, most common histologies being teratoma and neuroblastoma. We encountered a child who was detected to have a right arm mass on antenatal sonogram, which was diagnosed to be a primitive neuroectodermal tumor involving the triceps on fine needle aspiration cytology performed in the post-natal period. The child was successfully treated with multimodality treatment consisting of surgery, chemotherapy and radiotherapy. We also discuss briefly the problems associated with therapy in neonatal period. A review of all cases reported to have congenital Ewing’s sarcoma family of tumors is presented. Novel therapies are needed to improve efficacy and decrease the devastating side effects of treatment in this age group

‘Inverted Y’ field radiotherapy planning with multi-leaf collimator: A single isocentric technique using multiple fields

The purpose of our study is to describe a planning technique using multi-leaf collimator and asymmetric fields for irradiating an ‘inverted Y’ shaped geometry in a patient with testicular seminoma. The entire target area covering the para-aortic, pelvic, and inguinal nodal regions was split into three fields. Single isocenter half-beam block technique was employed. The fields were planned with antero-posterior and postero-anterior portals with a differential weightage. The dose was prescribed at the respective reference points of the fields. A uniform dose distribution for the entire portal was achieved without any under- or over-dosing at the field junctions.  </p

A Study on Morbidity Patterns amongst Hospitalized Patients Attending a New Tertiary Care Institute, India

Background: The pattern of morbidity reflects the burden of disease in a particular community. This pattern showsgeographic variations between communities and countries. The knowledge of the pattern of diseases in a given country is very important in evaluating its health care delivery system. Such knowledge is important for health planning and for improving the healthcare services in that particular nation. We set out to study the morbidity pattern in our medical wards. Materials and methods: This is a retrospective study that reviewed the causes of morbidity amongst admitted cases from January 2014 to December 2014. The data were obtained from the medical record section. Data were analyzed using software Statistical Package for Social Sciences (SPSS) version 16. Results: A total of 19,609 patients were admitted during the study period. Of these males were 10,556 (53.8%) and females were 9,053 (46.2%). Out of the total cases, 19203 patients (97.9%) were discharged or relieved as cured, 210 patients (1.1%) had expired. The sex ratio was 858 females to 1,000 males. Of the most common causes of morbidities/system involved (ICD.10) in males, chronic ischemic heart disease (4.7%) was the leading cause followed by live born infants (3.8%), hypertension (3.7%), lymphoid leukemia (2.7%) and malignant neoplasm of brain (2.1%). In females, malignant neoplasm of breast (6.2%) was the leading cause followed by delivery by caesarean section (4.9%), live born infants (3.8%), secondary malignant neoplasm of other and unspecified sites (3.1%) and hypertension (2.4%). Overall bed occupancy rate (BOR) for all patients was 66.8 percent. Conclusion: Morbidity in the medical wards reflects the emerging trend of mixed disease spectrum burden comprising communicable and non-communicable diseases. Public health education, raising the socio-economic status of our people and as well as improving the standards of our health care facilities and personnel can contribute towards bringing down morbidity and mortality rates from medical wards

Variations in superior thyroid artery: A selective angiographic study

Aim: To investigate variations in superior thyroid artery (STA) based on digital subtraction angiography (DSA). Materials and Methods: Twenty five angiography studies of 15 pts performed between June 2010 and December 2012 were retrospectively evaluated. These patients underwent DSA of the head and neck region as a part of their superselective neoadjuvant intra-arterial chemotherapy protocol for treatment of laryngeal and hypopharyngeal cancers. Depending upon the location of the tumor, unilateral or bilateral arteriograms of common carotid artery (CCA), external carotid artery (ECA), and STA were performed. Arteriograms were evaluated for the site of origin and branching pattern of STA. STA anatomy was ascribed to one of the three branching patterns. Results: A total of 25 angiograms were evaluated, including 14 right and 11 left. On the right side, STA was noted to arise from ECA in 10 (71.5%), bifurcation of CCA in 3 (21.5%), and CCA in 1 (7%) patient. Left STA was seen to arise from ECA in 8 (72.5%), bifurcation of CCA in 2 (18.5%), and internal carotid artery (ICA) in 1 (9%) patient. Type III branching pattern (non-bifurcation, non-trifurcation) was found to be the most frequent (52%). Infrahyoid branch was found to be the most consistent in terms of its origin from STA. Conclusions: Origin of STA is predictable, arising from ECA in more than 70% cases. Branching pattern of STA, following origin from ECA, is, however, highly variable. Knowledge concerning the origin and branching pattern of STA is essential in enhancing precision and decreasing morbidity related to the surgical and interventional radiological head and neck procedures

Malignant Peripheral Nerve Sheath Tumour of the Maxilla

A 38-year-old man was diagnosed with malignant peripheral nerve sheath tumour of the maxilla. He was treated with total maxillectomy. Histopathological examination of the resected specimen revealed a close resection margin. The tumour was of high grade with an MIB-1 labelling index of almost 60%. At six weeks following the surgery, he developed local tumour relapse. The patient succumbed to the disease at five months from the time of diagnosis. The present report underlines the locally aggressive nature of malignant peripheral nerve sheath tumour of the maxilla which necessitates an early therapeutic intervention. A complete resection with clear margins is the most important prognostic factor for malignant peripheral nerve sheath tumour in the head and neck region. Adjuvant radiotherapy may be considered to improve the local control. Future research may demarcate the role of targeted therapy for patients with malignant peripheral nerve sheath tumour