novel phantom design for brachytherapy quality assurance

Background: One major challenge in brachytherapy is to verify the accuracy of dose distributions calculated by the treatment planning system. In this project, a new phantom design has been introduced for quality assurance of dose distributions in gynocological [GYN] brachytherapy implants using EBT GafChromic film. Materials and Methods: This phantom has been designed and fabricated from 90 slabs of 18×16×0.2 cm[3] Perspex to accommodate a tandem and ovoids assembly, which is normally used for GYN brachytherapy treatment. In addition, this phantom design is allowing the use EBT GafChromic films for dosimetric verification of GYN implants with Cs-137 Selectron LDR system. With this assembly, GafChromic films were exposed using a plan designed to deliver 2.5 Gy dose to point "A" in Manchester system for tandem and ovoids configurations and to deliver 1.5 Gy of dose to 0.5 cm distance from the lateral surface of ovoids for using ovoid-pair. The measured dose distributions with GafChromic films were compared with the TPS isodose lines both numerically and spatially. For a quantitative analysis of the results, the measured doses values at several points of interest were evaluated with the treatment planning data and values obtained following the TG-43 dose calculation formalism. Results: The results of these investigations have indicated that the new phantom design enables us to measure differences of greater than +/-6% for LDR brachytherapy GYN treatments. Conclusion: The new phantom design could be utilized for the QA procedure of the brachytherapy remote after loading systems to confirm the accuracy of dose distribution in GYN implants

[Association between folate intake and breast cancer risk among Tehrani women: a case-control study]

Dietary folate deficiency may contribute to tumorogenesis in many sorts of malignancies. By considering the increasing incidence rate of breast cancer in Iran, this study was conducted to investigate the association between dietary folate intake and breast cancer risk. In this case-control study, 177 patients with breast cancer and 169 control subjects with no family history of malignancy were recruited from hospitals affiliated to Shahid-Beheshti University of Medical Sciences, Tehran. Standard questionnaires were used to collect data on demographic characteristics, physical activity, and food frequency consumption for the previous year. Total daily energy and folate intakes were estimated using the Nutritionist IV software. No statistically significant correlation was observed between daily dietary intake of folate and breast cancer risk in the sample population. However, the results showed a significant inverse association between daily intake of dietary folate and risk of breast cancer in postmenopausal women [OR=0.17; 95%CI: 0.035-0.88]. Increases in the strata of daily folate intakes were associated with decreasing trends of ORs in postmenopausal breast cancer risk [P[for trend] =0.036], where the OR of folate intake at the 2[nd] tertile was 0.26 [95%CI: 0.05-1.22] and at the 3[rd] tertile was 0.17 [95%CI: 0.035-0.88]. Based on the findings, folate intake was not correlated with breast cancer risk in the total sample population, whereas higher intakes of folate was inversely associated with postmenopausal breast cancer risk

Epidermal growth factor receptor gene in prostate cancer after radical prostatectomy

The aim of this study was to evaluate over expression of epidermal growth factor receptor [EGFR] gene in localized prostate cancers and determine its relation with clinical and pathological factors affecting the progression of the disease. In the tissue samples of the patients with prostate cancer undergoing radical prostatectomy, EGFR expression was evaluated by immunohistochemistry technique. Those with scores 2 and 3 were considered to be positive for the expression. The relation between gene expression and grade was evaluated by chi-square test. Of 100 tissue samples evaluated, 80 and 20 had Gleason score [GS] < 7 and >/= 7, respectively. Also, 68 and 32 had PSA level 10, respectively. A total of 59 samples were positive for EGFR expression, of whom, 46 had GS < 7 and 13 had GS > 7 [P-value = 0.39]. Forty patients had PSA < 10 and 19 had PSA > 10 [P-value = 0.5]. Fifty-nine percent of the patients with localized prostate cancer undergoing radical prostatectomy were EGFR positive. No significant relation was found between EGFR and grading [GS] or PSA

Changes in thyroid functional tests in breast Cancer patients under Tamoxifen therapy

Tamoxifen, a synthetic anti-estrogen agent, is administered as an adjuvant treatment in breast cancer. Since various studies have indicated that Tamoxifen can change some hormones and bound globolines, controversial results have been achieved using this medicine on Thyroid Functional Tests [TFT]. The present study was conducted to investigate the effects of Tamoxifen on TFT in women with breast cancer referred to oncology clinic in Imam Hossein hospital between 2001 and 2002. A quasi-experimental clinical trial study was performed on 23 women with breast cancer in a single blind basis [with no control group]. Patients were under Tamoxifen 20 mg P.O. daily and their serum TSH, free T4 and three Iodothyronine [T3] were assessed before treatment with Tamoxifen and after 3 months. Paired T test was used for statistical analysis. There was a significant difference in T3 before and after the treatment with Tamoxifen [p = 0.02], whereas no significant differences were seen in TSH [p = 0.095] and FT4 [p = 0.13]. This study showed that treatment with Tamoxifen in women suffering from breast cancer results in an increase in serum T3 but has no effect on serum TSH and FT4, therefore women under treatment with Tamoxifen remain euthyroid

Stage I seminoma recurrences in patients admitted to radiotherapy clinic of Shohada hospital between 1991 and 2002

Currently, cancers are among the important and main problems of health system in Iran and around the world. In young men under 20 to 35 years of age, malignant masses of testis are the most common tumours. The main pathologic feature of these masses is germ cell tumour and about half of them are seminoma. Since seminoma is very prevalent in the forth decade, being affected with this tumour leads to losing many years of healthy life. In a cross sectional study, investigating 139 records of patients with testis tumour revealed 61 patients with stage-1 seminoma. Thirty three patients underwent para-aortic and unilateral pelvic irradiation [54%] while 28 patients only underwent para-aortic irradiation [46%]. The administered radiotherapy dosage varied between 25-40 Gy Mean age of the patients was 37.8 of whom the youngest was 15 and the oldest was 64 years of age. Only one recurrent patient was seen in this cohort who was in para-aortic group. There was no significant difference in recurrence rate between the two radiotherapy methods. [p= 0.7]. Considering fewer complications of para-aortic irradiation and the insignificant difference in the recurrence rate between the two methods of radiotherapy, para-aortic method could be more appropriate and acceptable in the treatment of testicular cancer

5 year survival of breast cancer in Shohada-e- Tajrish and Jorjani Hospitals

Breast cancer is the most common cancer and the second most common cancer of cancer death in Iranian women after gastric carcinoma; although it is the second most common cancer in the western women after lung cancer. Its survival depends on multiple factors, which are very important to identify in order to understand natural history of the disease in Iran. In the present study, 154 patients with T1-T2-T3-NO-N1-MO breast cancer participated between March 1996 and March 1998 after surgery followed by adjuvant chemotherapy and/or radiation therapy and/or tamoxifen and were followed up for at least 5 years. Different factors might be effective on survival evaluation. Data was analyzed by SPSS, using chi-square and Kaplan Mayer method for survival analysis. 5 year survival was 76.5%.It decreased by lymph node involvement [72.9% versus 88.9%, p=0.034] and increased in estrogen receptor positive tumors [84.3% versus 62.5,p=0.024]. Left breast cancer patients survived more than right ones [87.5% versus 76.5%, p=0.004]. Tumor size, type of pathology, age, type of surgery [breast conservative surgery or mastectomy] progestrone receptors, HER-2 proto- oncogene and type of chemotherapy had no effect on survival. There is high survival by adjuvant therapy in Iran when breast cancers is detected at an early stage without lymph node involvement and receive appropriate therapy. The other factors should be studied more by future researches