No abstract

Radiation therapy is an important treatment modality for abdominal or pelvic cancer, but there is a common and serious complication such as radiation-induced enteritis. Probiotics is reported to have positive effects against radiation-induced enteropathy. In this study, morphological changes of bowel mucosa were analyzed in rats to presume the effect of probiotics on radiation-induced enteritis and its correlation with radiation dose. A total of 48 adult male Sprague-Dawley rats were randomly assigned to two groups and received a solution containing 1.0×108 colony-forming units of Lactiobacillus acidophilus or water once daily for 10 days. Each of two groups was divided into three subgroups and abdomino-pelvic area of each subgroup was irradiated with 10, 15, and 20 Gy, respectively on the seventh day of feeding the solutions. All rats were sacrificed 3 days after irradiation and the mucosal thickness and villus height of jejunum, ileum and colon were measured. The morphological parameters of the small intestine represented significant differences between two solution groups irradiated 10 or 15 Gy, except for villus height of jejunum in 15 Gy-subgroup (P=0.065). There was no significant morphometric difference between two groups irradiated with 20 Gy of radiation. Probiotics appear to be effective for the morphological shortening of small intestinal mucosa damaged by radiation less than or equal to 15 Gy.Graphical Abstract

PurposeThe objective of this study was to investigate the influence of radiotherapy on the cosmetic outcome after immediate breast reconstruction using an absorbable mesh in breast cancer.MethodsFrom July 2008 to July 2009, 35 breast cancer patients who received immediate breast reconstruction with absorbable mesh insertion at the time of breast conserving surgery followed by radiotherapy were retrospectively studied.ResultsIn 91% of cases there was an excellent or good cosmetic outcome before the initiation of radiotherapy, and in 8.6% the outcome was fair at this point. However, 6 months after surgery and irradiation, the rate of excellent to good cosmetic outcomes had decreased to 60% and fair outcomes had increased to 25.7%. Contrary to the decreased rate of good cosmetic outcomes from 65.7% to 42.9% at 1 year after operation, the rate of fair to poor outcomes considerably increased from 8.6% to 57.1%. The significant factors affecting cosmetic outcomes were pathology, specimen volume, and the estimated percentage of breast volume excised (EPBVE). Chemotherapy affected the cosmetic outcome at borderline significance level. Age, breast volume tumor site, insertion of drain, radiation dose, and time elapsed between surgery and radiotherapy were not significantly associated with the cosmetic outcome.ConclusionApplying an absorbable mesh for the immediate reconstruction of the breast should be carefully considered in patients with an EPBVE of over 30% who are scheduled to be irradiated.

PurposeThis study was performed to evaluate the change in the lumpectomy cavity volumes before and after whole breast radiation therapy (WBRT) and to identify factors associated with the change of volume.Materials and MethodsFrom September 2009 to April 2010, the computed tomography (CT) simulation data from 70 patients obtained before and after WBRT was evaluated. The lumpectomy cavity volumes were contoured based on surgical clips, seroma, and postoperative changes. Significant differences in the data from pre-WBRT CT and post-WBRT CT were assessed. Multiple variables were examined for correlation with volume reduction in the lumpectomy cavity.ResultsThe mean and median volume reduction in the lumpectomy cavity after WBRT were 17.6 cm3 and 16.1 cm3, respectively with the statistical significance (p < 0.001). The volume reduction in the lumpectomy cavity was inversely correlated with time from surgery to radiation therapy (R = 0.390). The presence of seroma was significantly associated with a volumetric change in the lumpectomy cavity after WBRT (p = 0.011).ConclusionThe volume of lumpectomy cavity reduced significantly after WBRT. As the time from surgery to the start of WBRT increased, the volume reduction in the lumpectomy cavity during WBRT decreased. A strong correlation was observed between the presence of seroma and the reduced volume. To ensure appropriate coverage and to limit normal tissue exposure during boost irradiation in patients who has seroma at the time of starting WBRT, repeating CT simulation at boost planning is suggested.

This study investigated the therapeutic effects of combined local irradiation and anti-HER2/neu antibody in a mixed tumor mouse model comprised of a nonmetastatic neu-positive tumor and a metastatic neu-negative tumor. While local irradiation alone could control the primary tumor in a dose-dependent manner, it did not improve mouse survival. Combined treatment comprised of local irradiation and anti-neu antibody of tumor-bearing BALB/c mice significantly improved mouse survival (P < 0.5), even though the tumor growth was similar to that of the irradiated-alone group. The combined treatment significantly reduced metastatic tumor masses in the lung and increased immune cell infiltration in primary tumor tissues. However, immune deficient nude mice with tumors did not exhibit prolonged survival in response to the combined treatment. Collectively, these results show that combined local irradiation and anti-neu antibody can elicit an immune-mediated abscopal effect to extend survival. Although the mechanism for abscopal effects induced by the combined treatment of radiation and anti-HER2/neu antibody was not elucidated, to our knowledge this is the first published study to describe the abscopal effect induced by the combination of local irradiation and the anti-HER2/neu antibody.