Search

The adequacy of setup margins for various sites in patients treated with helical tomotherapy was investigated. A total of 102 patients were investigated. The breakdown of the patients were as follows: Twenty-five patients each in brain, head and neck (H and N), and pelvis, while 12 patients in lung and 15 in craniospinal irradiation (CSI). Patients were immobilized on the institutional protocol. Altogether 2686 megavoltage computed tomography images were analyzed with 672, 747, 622, 333, and 312 fractions, respectively, from brain, H and N, pelvis, lung, and CSI. Overall systematic and random errors were calculated in three translational and three rotational directions. Setup margins were evaluated using van Herk formula. The calculated margins were compared with the margins in the clinical use for various directions and sites. We found that the clinical isotropic margin of 3 mm was adequate for brain patients. However, in the longitudinal direction it was found to be out of margin by 0.7 mm. In H and N, the calculated margins were well within the isotropic margin of 5 mm which is in clinical use. In pelvis, the calculated margin was within the limits, 8.3 mm versus 10 mm only in longitudinal direction, however, in vertical and lateral directions the calculated margins were out of clinical margins 11 mm versus 10 mm, and 8.7 mm versus 7.0, mm respectively. In lung, all the calculated margins were well within the margins used clinically. In CSI, the variation was found in the middle spine in the longitudinal direction. The clinical margins used in our hospital are adequate enough for sites H and N, lung, and brain, however, for CSI and pelvis the margins were found to be out of clinical margins.

Background: Patients with medical imaging performed and interpreted elsewhere often come to tertiary referral centers for further management. At our tertiary cancer hospital, external imaging studies of patients with head-and-neck cancer undergo formal second opinion reporting by subspecialty oncoradiologists. Objectives: We aimed to audit the second in-house review of outside scans by specialized head-and-neck radiologists to estimate the potential impact on patient management. Our secondary objective was to determine the direct impact of the second opinion by head-and-neck specialist radiologists on the change in diagnosis, stage, and management of patients. We also aimed to determine the indirect impact on the cost–benefit ratio and the time taken for decision making. Materials and Methods: This was a retrospective review of original and second opinion reports for consecutive patients that came with films/compact discs (CDs) and reports of computed tomography (CT), magnetic resonance imaging (MRI), or positron resonance imaging - computed tomography (PET-CT), initially performed and interpreted at another institution, and later, a second opinion review of imaging was done by the in-house subspecialty radiologists in head-and-neck onco-imaging between May 2016 and December 2017. The rates of discrepancy for staging and recommended management and the report accuracy were determined and compared to the gold standard: pathological staging. Results: Following the specialist in-house radiologist's second opinion review, the cancer stage changed in 28% (139/492) cases, and the management recommendation changed in 6.7% (67/492) of the patients with head-and-neck cancer. Compared to the histopathology results that were available for 93/492 (19%) cases, the second opinion interpretation was correct 87% of the time (81/93). The average time saved by the second radiology opinion was 8.6 days. Significant monetary savings amounting to ₹11,35,590 ($13,788.3) were achieved. Conclusion: A second opinion review of outside imaging in patients with head-and-neck cancer by expert in-house onco-radiologists results in a change in the stage of cancer and the management plan in a significant number of cases, saves time by expediting the work-up, and helps to avoid expenditure on repeat imaging.