Prior Knowledge-Guided U-Net for Automatic CTV Segmentation in Postmastectomy Radiotherapy of Breast Cancer.

Purpose: This study aimed to design and evaluate a prior-knowledge-guided U-Net (PK-UNet) for automatic clinical target volume (CTV) segmentation in postmastectomy radiotherapy for breast cancer.

Methods And Materials: A total of 102 computed tomography (CT) scans from breast cancer patients who underwent postmastectomy were retrospectively collected. Of these, 80 scans were used for training with 5-fold cross-validation, and 22 scans for independent testing.

Theoretical models for supercritical fluid extraction.

For the proper design of supercritical fluid extraction processes, it is essential to have a sound knowledge of the mass transfer mechanism of the extraction process and the appropriate mathematical representation. In this paper, the advances and applications of kinetic models for describing supercritical fluid extraction from various solid matrices have been presented. The theoretical models overviewed here include the hot ball diffusion, broken and intact cell, shrinking core and some relatively simple models.

[Dosimetric comparison between helical tomotherapy and step-and-shoot intensity modulated radiation therapy for endometrial carcinoma].

Background And Objective: Helical tomotherapy (HT) has shown its dosimetric advantages in the radiotherapy for many cancers. To date, no published studies have performed a dosimetric evaluation of whole pelvic radiotherapy (WPRT) using HT for postoperative endometrial cancer. This study was to compare the dosimetric characteristics of HT and step-and-shoot intensity modulated radiation therapy (SaS-IMRT) for endometrial cancer patients undergoing postoperative WPRT, and to explore whether whole pelvic HT for postoperative endometrial cancer has the advantage of dosimetry.

Interstitial permanent implantation of 125I seeds as salvage therapy for re-recurrent rectal carcinoma.

Purpose: To assess the feasibility, efficacy, and morbidity of (125)I seeds interstitial permanent implant as salvage therapy for re-recurrent rectal cancer.

Methods And Materials: From September 2003 to October 2007, (125)I seeds implant procedures were performed under CT or ultrasound guidance for thirteen patients with locally re-recurrent rectal carcinoma. The minimal peripheral doses (MPD) of (125)I seeds implanted ranged from 120 to 160 Gy, with a median MPD of 140 Gy to total decay.