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Dosimetric comparison of treatment of left breast cancer using two different dose schedules Dosimetric comparison of treatment of left breast cancer using two different dose schedules
Arezoo Kazemzadeh, Iraj Abedi, Alireza Amouheidari, Atefeh Shirvany,
Volume 78, Issue 9 (12-2020)
Abstract
Background: To date, different kinds of treatment methods have been proposed for radiotherapy of cancer patients. Choosing the kind of treatment method affects the quality of the patient's treatment. This study aims to investigate the effect of the number of radiation treatment sessions on the dose received by the patient and the distribution of tumor dose and dose received by organs at risk in breast cancer radiation therapy. These results help us to select the appropriate treatment schedules for the treatment of left breast patients.
Methods: This prospective cross-sectional study was performed on the treatment plans of 35 patients with left breast cancer who referred to Isfahan Milad Hospital between July 2019 and April 2020. They were candidates for left breast radiation therapy. Also, these patients had no history of surgery or chemotherapy, and no supraclavicular or axillary lymph nodes were involved. Patients were treated with a conventional fraction regimen (CF) or hypofractionated (HF) treatment schedule. Different dosimetry parameters for the target and organ at risks such as conformity index, homogeneity index and mean dose were obtained from the dose-volume histogram plot. Finally, the results of both plans were compared with each other.
Results: The data obtained from this study indicate a decrease in the average dose of all organs in the hypo fractionated regimens compared to conventional plans. The differences between two plans were statistically significant for tumor, lung, and skin (P=0.0). Moreover, the maximum dose for the skin was also reduced when hypofractionated regimens were used. However, the values of the homogeneity index and conformity index of tumor in the two methods did not show a significant difference (P were 0.99 and 0.86, respectively).
Conclusion: In general, the results of the current study indicate that the hypofractionated regimen leads to a reduction in dosimetric factors compared to conventional fraction plans. It seems that this method can be used as an alternative treatment plan for breast cancer radiation therapy due to the reduced duration of the treatment period.
 
Bartholin gland cancer in a young woman: a case report
Ali Taghizadeh, Leila Pourali , Amirhosein Jafarian , Farokh Seilanian Toosi , Ghazal Ghasemi, Marjaneh Farazestanian, Mitra Enzebati,
Volume 79, Issue 11 (2-2022)
Abstract
                                                                        
 
 
 
 
 
 
 
Background: With 6,020 new cases and 1,150 deaths annually in the United States, vulvar cancer is uncommon, resulting in age-adjusted incidence rates of 2.8 and 1.7 per 100,000 in white and black women, respectively. Vulvar cancer represents about 4% to 6% of malignancies of the female genital tract and 0.6% of all cancers in women. Vulvar cancer predominantly affects postmenopausal women, and it is the most common anogenital cancer in women with more than 70 years of age. HPV infection is associated with a significant number of vulvar cancers. Bartholin Gland carcinoma is a rare form of vulvar malignancy that accounts for less than 5% of all vulvar cancers and 0.001% of all genital cancers. The aim of this study was to report a rare case of Bartholin's cancer in a young patient.
Case Report: The patient was a 37-year-old woman p2l2 (history of two pregnancy and two delivery) who had complains of severe pain in perineal area and was referred to the gynecology emergency clinic, Ghaem Hospital, Mashhad University of Medical Sciences, Mashhad, Iran, in June 2020. In past medical history she had no previous history of medical illnesses or surgical interventions. She had swelling and pain in perineal area since one year ago. Bartholin Gland abscess was diagnosed and she received some oral antibiotics, but did not improve. On the last examination under anesthesia, a firm mass of about 3 cm was palpated in the third distal part of posterior vagina which was at the site of Bartholin Gland and was necrotic. The pathologic report of the mass biopsy confirmed the diagnosis of squamous cell carcinoma. The patient was underwent chemo radiation therapy. At a follow up visit about 5 month later she was cured completely and there was not any symptom of recurrence or metastasis.
Conclusion: In dealing with any patient with diagnosis of Bartholin Gland abscess, in the case of resistance to medical treatment, further evaluation and biopsy of the mass should be considered to rule out Bartholin's gland cancer.
 

 

An evaluation of treatment volume coverage and dose delivered to vital organs in the management of low-grade brain gliomas using three-dimensional conformal radiotherapy (3DCRT) compared to intensity-modulated radiation therapy (IMRT)
Reza Ghalehtaki, Mahdieh Razmkhah, Ali Kazemian, Mostafa Farzin, Samaneh Salarvand, Kasra Kolahdouzan, Ehsan Saraee,
Volume 82, Issue 10 (1-2025)
Abstract
Background: Gliomas are the most common primary brain tumors in adults, with low-grade gliomas making up 15% of cases. These slow-growing tumors often occur in young adults. Radiotherapy is one of the treatment options. New radiotherapy techniques like IMRT may reduce complications by sparing normal tissue. The study aims to determine which tumors benefit most from IMRT based on tumor location and size.
Methods: Patients diagnosed with low-grade glioma who were referred for treatment at the Cancer Institute of Imam Khomeini Hospital between September 2017 and September 2020 were included in this study. All patients underwent CT simulation with a thermoplastic mask for immobilization. A diagnostic MRI (performed within two weeks prior) was fused with the planning CT to define the target volume (GTV/CTV), with contours verified by a neuroradiologist. A doctor outlines the treatment volume and critical organs for both 3D and IMRT techniques. Radiotherapy physics experts design treatment plans using both techniques, which are then approved by a radiation oncologist. The treatment volume coverage and doses to critical organs are compared between the two techniques.
Results: Among 25 patients, 14 patients (56%) with single-lobe involvement, 7 (28%) with two lobes, and 4 (16%) with multifocal disease. Right-side brain involvement was seen in 32%, with the frontal lobe most affected. IMRT significantly reduced the mean and maximum cochlear dose on the treatment side in all patients. It also lowered the mean chiasma dose in those with both lobes involved and reduced cochlear dose on the opposite side in frontal lobe cases. No significant difference was found between the techniques for patients with multiple lobe involvement.
Conclusion: According to our study on 25 patients with low-grade glioma, it was shown that there is no clear difference between the two techniques. Given the young age and long survival of LGG patients, IMRT may be preferred when hearing preservation is a priority. Further studies with larger cohorts are needed to confirm these findings.

Evaluation of the accuracy of MAGIC polymer gel dosimeter in measuring dose in small electron fields in radiotherapy
Soraya Ahmadian Mask , Abbas Haghparast,
Volume 82, Issue 10 (1-2025)
Abstract
Background: Recent advances in modern radiotherapy techniques such as Intensity-Modulated Radiation Therapy (IMRT) and Stereotactic Radiosurgery (SRS) have significantly increased the need for accurate and reliable dosimetry in radiation therapy. Accurate dose delivery is particularly critical in small electron fields, which are increasingly used in targeted treatments. However, these fields pose unique challenges due to factors such as electron disequilibrium, increased lateral scatter, and steep dose gradients. These physical characteristics can introduce significant uncertainties in dose distribution, thereby reducing the effectiveness and safety of the treatment if not properly accounted for. Traditional dosimeters often struggle to maintain accuracy under such conditions. The aim of this study was to evaluate the performance of MAGIC polymer gel as a three-dimensional (3D) dosimeter in small electron fields and to compare its dosimetric characteristics with standard dosimeters including diode, semiflex, and pinpoint.
Methods: This experimental and applied study was conducted at the Radiotherapy Department of Imam Reza Hospital, Kermanshah, Iran, over a one-year period from December 2022 to December 2023. Five electron field sizes (2×2, 2.5×2.5, 3×3, 4×4, and 5×5 cm²) were generated using an Elekta linear accelerator at two electron beam energies of 6 and 9 MeV. MAGIC polymer gel phantoms were irradiated accordingly and scanned with a 1.5 Tesla MRI system to obtain three-dimensional dose distributions. These were compared to measurements obtained from diode, semiflex, and pinpoint dosimeters.
Results: The depth dose curves of MAGIC gel exhibited greater agreement with diode measurements compared to those from semiflex and pinpoint detectors. As field size decreased and beam energy increased, discrepancies in absorbed dose readings between different dosimeters became more apparent. These results underscore the importance of selecting appropriate dosimetric tools for accurate dose evaluation in small-field electron beams.
Conclusion: MAGIC polymer gel demonstrated strong potential as a reliable 3D dosimeter for small electron field dosimetry, showing the highest compatibility with the diode dosimeter.

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