Comparison of photon versus electron for tumor bed boost radiotherapy post-breast conserving surgery.

INTRODUCTION: The standard treatment (photon or electron) for tumor bed boost in breast cancer has not yet been clearly established. The aim of this work was to compare photon vs. electron for tumor bed boost radiotherapy post breast-conserving surgery and whole-breast irradiation concerning different dosimetric parameters. METHODS: This study included 51 patients who underwent conservative surgery and adjuvant radiotherapy. Of these, 28 patients had right-sided and 23 patients had a left-sided tumors. All patients in this study were treated with photon and then re-planned with electron plans. RESULTS: Both techniques electron and photon plans provided acceptable results while there was a better performance of the latter in terms of target coverage with statistical significance (p < 0.05). The global and maximum dose was significantly higher with electron compared to photon. Homogeneity index (HI) and conformity index (CI) and conformity number (CN) were better in photon plans, especially in deep-seated tumors. The quality of electron plans differed between patients according to depth, irregular shapes, and location of the tumor bed boost. The results of organs at risk (OARs) for ipsilateral lung and heart showed that photon plans were better than electron plans (p < 0.05), especially at a low dose (V2Gy and V1Gy) for ipsilateral lung. For contralateral breast, both photon and electron had nearly comparable results, where the dose delivered to the contralateral breast for both techniques was close to zero. Interestingly, the number of monitor units (MU) was reduced in electron compared to photon by 15.94% (p < 0.001). CONCLUSIONS: This study recommends the use of photon in treatment of tumor bed boost in conservative breast cancer and then electron as a second line when the former is not available.

The Pattern of Causes of Pneumoperitoneum-induced Peritonitis: Results of an Empirical Study.

Pneumoperitoneum refers to presence of free air within the peritoneal cavity, "Pneumoperitoneum induced Peritonitis" is synonymous of surgical pneumoperitoneum, as the leak of air and visceral contents contaminates the peritoneal cavity, producing peritonitis which mandates surgery. This entire pneumoperitoneum may result from inflammatory conditions, traumatic injury, neoplasia, anastomotic leak and vascular causes. The objectives of this study is to determine the incidence of Pneumoperitoneum-induced Peritonitis (surgical pneumoperitoneum) in emergency exploratory laparotomies, to identify the common anatomical sites of perforations and to review the pathological etiology of these cases. Review of 450 cases of emergency exploratory laparotomy cases performed in King Abdulaziz University Hospital from January 2011 to December 2015, among them 131 cases with radiologically documented pneumoperitoneum were selected to be involved in the study of surgical pneumoperitoneum, the anatomical site of perforation and the exact underlying pathology were documented. 29% of exploratory laparotomy cases were found to have pneumoperitoneum, mainly in the in the gastroduodenal region, inflammatory conditions as peptic ulcer disease or diverticulitis were the underlying cause of most of perforations. Pneumoperitoneum frequently indicates bowel injury or disease, hence it is called surgical pneumoperitoneum, Perforations are commonly found in gastro-duodenal area, the inflammatory conditions are responsible for the vast majority of cases, however presence of air with intact bowel, is called Non-Surgical or spontaneous Pneumoperitoneum, which has to be approached conservatively.