Wireless sensor networks are attracting a great deal of research interest. One of the most interesting researches in these networks is localization of sensor nodes whose accurate is a strong requirement in many applications. In recent years, several techniques have been proposed for localization in wireless sensor networks. In this paper, we present a localization scheme using only one mobile anchor station with receiving signal strength indicator technique, which reduces average localization errors and execution time. The satisfactory simulation results and also comparison of localization errors and execution time between our scheme and similar previous schemes depicts the efficiency of proposed method against previous schemes.

Background: Sentinel lymph node biopsy is a technique used to identify the axillary node most likely to contain tumor cells that have metastasized from a primary carcinoma of the breast. This technique provides accurate staging with fewer complications than axillary dissection and may result in decreased costs. We designed the present study to determine the accuracy and success rate of a combined blue dye and radioactive tracer technique in sentinel node localization.Methods: This prospective study included 70 patients with early stage (tumor>5 cm; T1, T2) operable breast cancer and nonpalpable axillary lymphadenopathy seen between 2005 and 2009. Patients underwent sentinel lymph node localization using 4 mL of blue dye combined with radioactive colloid. After identification and removal of the sentinel node (s), the axilla was checked for any residual radioactivity. A sentinel node was defined as any node that was hot, hot and blue or only blue.Results: The sentinel node was identified in 66 patients with a detection rate of 94.2%, and a mean of 1.5 sentinel nodes were identified and harvested (range of 1-4). In 23 cases, the sentinel lymph node contained metastatic disease on pathological assessment.There was no pathological evidence of any metastases in the sentinel node in the remaining 43 patients. All sentinel lymph nodes were located in level I of the axillary region. In four patients, no sentinel lymph node was found, so axillary dissection was performed. The sensitivity of the procedure in predicting further axillary disease was 95.6% with a specificity of 97.6%.Conclusion: The present study describes the blue dye and radioisotope localization technique as successful in identifying the sentinel lymph node in early-stage breast cancer patients.

Background: Breast cancer has the highest incidence and mortality among female malignant tumors. Breast cancer with negative axillary lymph nodes has been diagnosed mainly at an early stage. Sentinel lymph node biopsy (SLNB) is a standard screening technique for patients with early-stage breast cancer and clinically negative lymph nodes. Lymphoscintigraphy (sentinel lymph node mapping) has been regularly used as the standard method for SLNB. Today, ultrasound-guided wire localization (USGWL) is a well-established technique with superior outcomes. Therefore, we attempted to determine whether preoperative UGWL and lymphoscintigraphy (blue dye and isotope injection) improve SLN detection and false-negative rate in breast cancer patients undergoing SLNB and identify clinical factors that may affect the diagnostic accuracy of axillary ultrasound (AUS). Methods: Between December 2018 and June 2019, 55 patients with clinical T1-3N0 breast cancer eligible for an SLNB at Imam Khomeini Hospital in Tehran were included in our study. Tumor characteristics and demographic data were collected by reviewing medical records and questionnaires prepared by our surgical team. The day before SLNB, all patients underwent ultrasound-guided wire localization of SLN. Lymphoscintigraphy was performed with an unfiltered 99mTc-labelled sulfur colloid peritumoral injection followed by methylene blue dye injection. The results were analyzed based on the permanent pathology report. Results: Among the 55 patients, 71. 8% of SLNs were detected by wire localization, while 57. 8% were found by methylene blue mapping and 59. 6% by gamma probe detection. Compared with wire localization and isotope injection, the methylene blue dye technique had a low sensitivity (72. 2%), while both wire localization and isotope injection reached 77. 8%. The sensitivity, specificity, and accuracy of UGWL were 77. 8%, 42. 1%, and 65. 4%, respectively. Otherwise, methylene blue dye and isotope injection accuracy was 47. 3% and 50. 1%, respectively. Furthermore, there was a significant relationship between BMI, tumor size, laterality, reactive ALN, and the accuracy of preoperative AUS. But there was no significant correlation between age, weight, height, tumor biopsy, tumor location, the time interval between methylene blue dye and isotope injection to surgery, and also the type of surgery to the accuracy of preoperative AUS. Conclusion: Preoperative UGWL can effectively identify SLNs compared to lymphoscintigraphy (blue dye and isotope injection) in early breast cancer patients undergoing SLNB.

Background: Pre-operative localization options in the axilla are limited. This study aimed to explore the utility of pre-operative localization of axillary lymph nodes using tattoo ink with multidisciplinary correlations. Methods: In this prospective, Institutional Review Board (IRB)-approved study, 19 lymph nodes in 17 patients underwent pre-operative localization with ultrasoundguided injection of Spot tattoo ink. The success rate of intraoperative identification of the tattooed node as well as the frequency in which the tattooed node was also a sentinel node were recorded. Radiologic, surgical and pathologic images were collected. Results: Tattoo ink localization was successful in 16/17 (94. 1%) of patients. Tattoo ink did not hinder pathologic evaluation in any cases but was taken up by additional adjacent nodes in 1/17 successful localizations (5. 9%). Successful sentinel lymph node biopsy (SLNB) occurred in 13 patients in whom 14 lymph nodes underwent pre-operative tattoo ink localization. Nine of the 14 (64. 2%) tattooed lymph nodes were also a sentinel node. Conclusion: In this study, pre-operative localization of axillary lymph nodes with tattoo ink was highly successful In patients undergoing SLNB, a significant number of the tattooed nodes were not sentinel nodes (35. 8%), suggesting the importance of targeted lymph node excision in addition to SLNB.

Background: The importance of dose in prostate radiotherapy is well known, and the dosimetric effects of radiotherapy in node-positive or node-negative patients with prostate cancer have become an important issue. Materials and Methods: Helical tomotherapy (TH) plans of 19 pelvic node-positive [THpn(+) plan] or node-negative [THpn(-) plan] patients with prostate cancer were retrospectively created in our clinic. In these plans, the beam angle was set to cover the planning target volume (PTV) of prostate cancer and minimize the dose to the organs at risk, including the bladder, rectum, femoral head, and bowel. Results: There were no differences in the conformity index, Dmax, Dmean, and homogeneity index of PTV between the THpn (+) and THpn (-) plans (p>0. 05). However, V95 in the THpn (+) plan was lower than that in the THpn (-) plan (p=0. 017). Moreover, Dmax, V75, V70, V65, V60, V50, V40, V30, and V20 for the rectum were not significantly different between the two plans (p>0. 05), whereas Dmean was significantly different (p=0. 025). Dmax, V70, V65, and V60 for the bladder were not significantly different between the two plans (p>0. 05), whereas V55, V50, V40, and V30 were significantly different (p<0. 05). Finally, Dmax and V50 for the femoral head and bowel were significantly different between the two plans (p<0. 05). Conclusion: The THpn (+)] and [THpn(-) plans achieved acceptable target dose coverage in prostate radiotherapy.