Ninety-degree angled collimator: a dosimetric study related to dynamic intensity-modulated radiotherapy in patients with endometrial carcinoma.

BACKGROUND: Our purpose was to ensure that the dose constraints of the organs at risk (OARs) were not exceeded while increasing the prescription dose to the planning target volume (PTV) from 45 to 50.4 Gray (Gy) with the dynamic intensity-modulated radiotherapy (IMRT) technique. While trying for this purpose, a new dynamic IMRT technique named 90° angled collimated dynamic IMRT (A-IMRT) planning was developed by us. METHODS: This study was based on the computed tomography data sets of 20 patients with postoperatively diagnosed International Federation of Gynecology and Obstetrics stage 2 endometrial carcinoma. For each patient, conventional dynamic IMRT (C-IMRT, collimator angle of 0° at all gantry angles), A-IMRT (collimator angle of 90° at gantry angles of 110°, 180°, 215°, and 285°), and volumetric modulated arc therapy (VMAT) were planned. Planning techniques were compared with parameters used to evaluate PTV and OARs via dose-volume-histogram analysis using the paired two-tailed Wilcoxon's signed-rank test; p < 0.05 was considered indicative of statistical significance. RESULTS: All plans achieved adequate dose coverage for PTV. Although the technique with the lowest mean conformality index was A-IMRT (0.76 ± 0.05) compared to both C-IMRT (0.79 ± 0.04, p = 0.000) and VMAT (0.83 ± 0.03, p = 0.000), it protected the OARs especially the bladder (V45 = 32.84 ± 2.03 vs. 44.21 ± 6.67, p = 0.000), rectum (V30 = 56.18 ± 2.05 vs. 73.80 ± 4.75, p = 0.000) and both femoral heads (V30 for right = 12.19 ± 1.34 vs. 21.42 ± 4.03, p = 0.000 and V30 for left = 12.58 ± 1.48 vs. 21.35 ± 4.16, p = 0.000) better than C-IMRT. While the dose constraints of the bladder, rectum and bilateral femoral heads were not exceeded in any patient with A-IMRT or VMAT, they were exceeded in 19 (95%), 20 (100%) and 20 (100%) patients with C-IMRT, respectively. CONCLUSIONS: OARs are better protected when external beam radiotherapy is applied to the pelvis at a dose of 50.4 Gy by turning the collimator angle to 90° at some gantry angles with the dynamic IMRT technique in the absence of VMAT.

Male Breast Cancer: 20 Years Experience of a Tertiary Hospital from the Middle Black Sea Region of Turkey.

BACKGROUND: Male breast cancer is a rare neoplasm, and its treatments are based on those of female breast cancer. This study aimed to analyze 20 years of male breast cancer clinical characteristics and treatment results from the Middle Black Sea Region of Turkey. MATERIALS AND METHODS: A retrospective analysis of 16 male breast cancer patients treated in our tertiary hospital between 1994 and 2014 was performed. Epidemiologic data, tumor characteristics, and treatments were recorded and compared with 466 female breast cancer ((premenopausal; n=230)+(postmenopausal n=236)) patients. The 5-year disease-free and overall survival rates were calculated. RESULTS: Male breast cancer constituted 0.1% of all malignant neoplasms in both sexes, 0.2% of all malignant neoplasms in males, and 0.7% of all breast cancers. The mean patient age in this study was 59.8±9.5 (39-74) years. The mean time between first symptom and diagnosis was 32.4±5.3 (3-60) months. Histology revealed infiltrative ductal carcinoma in 81.3% of patients. The most common detected molecular subtype was luminal A, in 12 (75%) patients. Estrogen receptor rate (93.8%) in male breast cancer patients was significantly higher than that in female breast cancer (70.8% in all females, p=0.003; 68.2% in postmenopausal females, p=0.002) patients. Most of the tumors (56.3%) were grade 2. Tumor stage was T4 in 50% of males. The majority (56.3%) of the patients were stage III at diagnosis. Surgery, chemotherapy, radiotherapy and endocrine-therapy were applied to 62.5%, 62.5%, 81.2% and 73.3%, respectively. Loco-regional failure did not occur in any of the cases. All recurrences were metastastic. The 5-year disease-free and overall survival rates in male breast cancer patients were 58% and 68%, respectively. CONCLUSIONS: Tumors found in male breast cancer patients were similar in size to tumors found in females, but they advanced to T4 stage more rapidly because of the lack of breast parenchymal tissues. The rate of estrogen receptor expression tended to be higher in male breast cancer patients than in female breast cancer patients. Metastasis is the most important problem in initially non-metastatic male breast cancer patients.

Efficiency of apparent diffusion coefficients in differentiation of colorectal tumor recurrences and posttherapeutical soft-tissue changes.

OBJECTIVE: To evaluate effectiveness of apparent diffusion coefficient (ADC) values measured by diffusion-weighted magnetic resonance imaging (DW-MRI) in differentiation of colorectal tumor recurrences and posttherapeutical soft tissue changes. METHODS: For this prospective study, 30 patients (22 males, 8 females; age range 30-81 years; mean age 61±12 years) who underwent surgery for colorectal tumors and had a mass detected by computed tomography (CT) and/or MRI during follow-up examinations were divided into 2 groups [17 patients (Group 1) with recurrence and 13 patients (Group 2) with benign fibrosis/granulation tissue]. Final diagnoses were based on histopathological examination in 14 patients and clinical follow-up at least 6 months in the remaining 16. In the latter, the diagnosis of recurrence was made in cases in which the lesion was larger on follow-up CT and MRI; recurrence was ruled out in cases of stable or shrinking lesions without any increase in tumor markers. DW-MRI was performed in the axial plane, for two different b values (b=0 and 800 s/mm(2)). The mean apparent diffusion coefficient (ADC) values were measured by manual delineation of regions of interest on ADC maps. RESULTS: The median ADC values were 1.07 × 10(-3)mm/s(2) (min: 0.82, max: 2.05) and 1.91 × 10(-3)mm/s(2) (min: 1.51, max: 2.22) in Groups 1 and 2, respectively. A statistically significant difference was detected between the two groups (P<0.001). When the threshold value used to determine whether the lesions recurred was 1.48 × 10(-3)mm/s(2) based on ROC analysis, the sensitivity was 82% and the specificity was 100%. There were three patients with a false-negative diagnosis, and the primary histopathological diagnosis of all was mucinous adenocarcinoma. CONCLUSIONS: Because recurrences in mucinous adenocarcinomas have high ADC values, they may show overlap with benign lesions. In the detection of the local recurrence of colorectal neoplasms, with the exception of mucinous adenocarcinomas, ADC measurements are reliable imaging techniques.

Prognostic significance of concomitant radiotherapy in newly diagnosed glioblastoma multiforme: a multivariate analysis of 116 patients.

BACKGROUND AND OBJECTIVES: Currently, radiotherapy with concomitant and adjuvant temozolomide has become the standard treatment for glioblastoma. The purpose of this study was to report our experience with radiation plus concomitant temozolomide in 116 patients with glioblastoma multiforme (GBM) and examine the value of different prognostic factors. DESIGN AND SETTING: Retrospective analysis of 116 patients with newly diagnosed GBM, who were treated at our department between January 1994 and March 2009. PATIENTS AND METHODS: Age, gender, Karnofsky performance scale (KPS) score, a preoperative history of seizures, extent of surgery, total radiotherapy dose, and use of concomitant and adjuvant temozolomide were evaluated in uni- and multivariate analyses. Survival was determined using the Kaplan-Meier method, and differences were compared using the log rank test. Cox regression analysis was conducted to identify the independent prognostic factors. RESULTS: The median overall survival time was 9 months, and the 1- and 2-year survival rates were 41.9% and 9.6%, respectively. The univariate analysis revealed that age, KPS score, presence of seizures, radiation doses, and use of concomitant and adjuvant temozolomide were significant prognostic factors. The multivariate analysis confirmed that the age, KPS score, presence of seizures, radiation doses, and use of concomitant and adjuvant temozolomide were independent, significant prognostic factors. CONCLUSIONS: The results of our analyses demonstrate that radiation with concomitant and adjuvant temozolomide yields encouraging outcomes in patients with GBM, validating the results published in research papers. In addition, age, KPS score, presence of seizures, and radiation doses were identified as prognostic factors.