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.

In order to solve some security issues in Wireless Sensor Networks (WSNs), node to node authentication method based on digital watermarking technique for verification of relative nodes is proposed. In the proposed method, some algorithms with low computational for generation, embedding and detection of security ID are designed. The collected data packets by the nodes are marked using security ID. In the proposed method, header is used to mark the packets. Since the nature of the sensor networks is cooperative, using the head of the packets is proposed for authentication. Also using the marked head can prevent from sending and receiving fake data in the other nodes. Simulations have been performed in environments with imposing unrealistic data and having a probability from 1% to 10%. Comparing the proposed method with other methods shows that the proposed method in term of security, reducing traffic and increasing network lifetime is more effective.

Background: Neoadjuvant chemotherapy (NAC) is increasingly used to treat patients with breast cancer, but the reliability of sentinel lymph node biopsy (SLNB) following chemotherapy is in doubt. In this meta‑ analysis, we aimed to evaluate studies that examine the results of SLNB after NAC to assess identification rate (IR) and false‑ negative rate (FNR). Materials and Methods: Systemic searches were performed in the PubMed, ISI Web of Sciences, Scopus, and Cochrane databases from January 1, 2000, to November 30, 2016, for studies of SLNB after NAC for breast cancer and followed by axillary lymph node (LN) dissection in two subgroups: initially node negative and node positive converted to node negative. Two reviewers independently review quality of included studies. A random‑ effects model was used to pool IR and FNR with 95% confidence intervals (CI), and heterogeneity among studies was assessed by I2 and Q‑ test. Results: A total of 23 studies with 1521 patients in the initially node‑ negative subgroup and 13 studies with 1088 patients in the node‑ positive converted to node‑ negative subgroup, were included in this meta-analysis with IR and FNR of 94% (95% CI: 92– 96) and 7% (95% CI: 5– 9) in the initially node‑ negative subgroup and 89% (95% CI: 85– 94) and 13% (95% CI: 7– 18) in the node‑ positive converted to node‑ negative subgroup, respectively. Conclusion: Our meta‑ analysis showed acceptable IR and FNR in initially node‑ negative group and it seems feasible in these patients, but these parameters did not reach to predefined value in node‑ positive converted to node‑ negative group, and thus, it is not recommended in these patients.

Background: Sentinel lymph node biopsy is used as an accurate staging procedure to detect early breast cancer. Several studies have documented that sentinel lymph node biopsy can accurately determine the status of axillary nodes. Sentinel node biopsy offers the advantage of accurately staging the axilla and eliminating the need for a full axillary dissection for patients who have a negative sentinel node. The aim of this study is to determine the predictors of non-sentinel lymph node metastasis by sentinel node biopsy.Methods: In this study, all patients (n=88) who underwent sentinel node biopsy for invasive breast cancer from June 2005 to June 2010 in Shahid Faghihi Hospital, Shiraz, Iran were enrolled. We reviewed the medical files of patients and their tumor characteristics. Statistical analysis was performed to determine whether any of these characteristics alone could accurately predict the remaining non-sentinel node status.SPSS statistical package was used.Results: The mean age of the patients was 46.1 years. Tumor size was 2.73 cm. Of the 88 patients who underwent complete axillary node dissection, 34 had metastases in the non-sentinel nodes, with a mean of 4 positive non-sentinel nodes in each patient.Statistically, neither the patient's age nor the clinicopathological features of the tumor were significantly associated with non-sentinel node metastases (all: P>0.05).Conclusion: Our study shows that neither the primary tumor characteristics nor the size of metastasis in the sentinel lymph node can predict the status of non-sentinel nodes.However, further investigation is necessary. Complete axillary node dissection should remain the most appropriate management for patients with positive sentinel lymph nodes.