Tehran University Medical Journal

Background: In three-dimensional conformal radiation therapy (3D-CRT), contrast-enhanced CT (CECT) image is commonly used to assist radiation oncologists in diagnosing regions of interest, so that normal and target tissues can be better delineated. CECT causes the temporary increase in the CT number and the corresponding electron density (ρe). Administrated contrast agents (CA) during CT simulation and altering the ρe of structures can be effective on radiation calculations and dose-volume histograms (DVHs) in radiotherapy treatment planning. Therefore, present study was designed and performed to determine the influence of the administrated CA on DVHs.
Methods: Current study performed as a self-controlled clinical trial study with before/after method at Imam Reza Hospital, Kermanshah City, during the period from June 2015 till August 2016. Ten patients with pelvic cancer included in this study through simple sampling. Cases with prior reactions to CA, diabetes, renal diseases, and asthma were excluded. Two sets of CT-scans were taken for each patient in the same position and coordinates. Primary study sets contained pre-contrast images and secondary study sets were performed post-contrast. Both sets of CT images were transferred to the treatment planning system (ISOgray® software, Version 4.1.3.23 L, DOSIsoft®, Cachan, France). All treatment plans were generated on pre-contrast and subsequently copied to the post-contrast CT. Quantitative calculations were performed in treatment planning including the difference in ρe before and after CA administration.
Results: The prostate (1.27%), the bladder (0.62-0.79%) and the rectum (0.43-0.56%) showed the largest changes in average ρe increase. The results confirm the expected relationship of increasing attenuation, CT number, and ρe with increased tissue density due to the CA. However, the DVHs showed insignificant difference between pre-and post-contrast CTs for 18 MV photon beam.
Conclusion: The results showed statistical insignificant difference between with and without CA CTs treatment plan in pelvic field for targets and OARs. These results may serve as a reference to justify the use of CECT data sets for 3D-CRT planning of pelvic region cancers using DosiSoft ISOgray system.

Background: Melatonin is one of the drugs which are used in the treatment of sleep problems, including insomnia and sleep deprivation. The aim of the present study was to evaluate the melatonin effect on sleep quality in patients with cancer.
Methods: This quasi-experimental study was performed on cancer patients with trouble sleeping who were treated with melatonin (3 mg per day) for a month. Sleep quality according to the Pittsburgh sleep quality index (PSQI) questionnaire was evaluated before and after taking melatonin. This study was conducted in the Oncology Clinic of Imam Reza Hospital, Kermanshah City in Iran from August 2016 to February 2018.
Results: There was a significant difference between the sleep quality of patients with cancer before and after taking melatonin (P<0.05). In other words, before taking melatonin, sleep quality of none of the patients was not optimal but after taking melatonin, the sleep quality of 52% of patients was satisfactory. Also, there was a significant difference between the components of subjective sleep quality (P<0.001), sleep latency (P<0.001), sleep duration (P<0.001), sleep efficiency rate (P<0.001), sleep disturbances (P=0.001), and daytime dysfunction (P<0.001) of patients with cancer before and after taking melatonin. There was no significant difference between the components of subjective sleep quality, sleep latency, sleep duration, sleep efficiency rate, sleep disturbances, and daytime dysfunction of cancer patients with age, sex, kind of cancer, and kind of metastasis before and after taking melatonin (P˃0.05).
Conclusion: According to the mentioned findings, it seems that the administration of melatonin to enhance sleep quality in patients with cancer is effective.