Search Results Heading

MBRLSearchResults

mbrl.module.common.modules.added.book.to.shelf
Title added to your shelf!
View what I already have on My Shelf.
Oops! Something went wrong.
Oops! Something went wrong.
While trying to add the title to your shelf something went wrong :( Kindly try again later!
Are you sure you want to remove the book from the shelf?
Oops! Something went wrong.
Oops! Something went wrong.
While trying to remove the title from your shelf something went wrong :( Kindly try again later!
    Done
    Filters
    Reset
  • Discipline
      Discipline
      Clear All
      Discipline
  • Is Peer Reviewed
      Is Peer Reviewed
      Clear All
      Is Peer Reviewed
  • Item Type
      Item Type
      Clear All
      Item Type
  • Subject
      Subject
      Clear All
      Subject
  • Year
      Year
      Clear All
      From:
      -
      To:
  • More Filters
      More Filters
      Clear All
      More Filters
      Source
    • Language
531 result(s) for "Intraoperative radiation therapy"
Sort by:
Intraoperative radiation therapy for colon and rectal cancers: a clinical review
Although there have been significant advances in the adjuvant therapy of colorectal cancer, results for patients have historically been poor when complete resection is unlikely or not possible. Similarly, locally recurrent colorectal cancer patients often experience significant tumor related morbidity and disease control and long term survival have historically been poor with standard therapies. Intraoperative radiation therapy (IORT) has been proposed as a possible tool for dose escalation in patients with locally advanced colorectal cancer. For patients with locally advanced primary or recurrent colon cancer, the absence of prospective controlled trials limits the ability to draw definitive conclusions in completely resected patients. In subtotally resected patients, the available evidence is consistent with marked improvements in disease control and survival compared to historical controls. For patients with locally advanced primary or recurrent rectal cancer, a relatively large body of evidence suggests improved disease control and survival, especially in subtotally resected patients, with the addition of IORT to moderate dose external beam radiation (EBRT) and chemotherapy. The most important prognostic factor in nearly all series is the completeness of surgical resection. Many previously irradiated patients may be carefully re-treated with radiation and IORT in addition to chemotherapy resulting in long term survival in more than 25% of patients. Peripheral nerve is dose limiting for IORT and patients receiving 15 Gy or more are at higher risk. IORT is a useful tool when dose escalation beyond EBRT tolerance limits is required for acceptable local control in patients with locally advanced primary or recurrent colorectal cancer. Previously irradiated patients should not be excluded from treatment consideration.
Intraoperative radiation therapy induces immune response activity after pancreatic surgery
Background Pancreatic cancer has highly aggressive features, such as local recurrence that leads to significantly high morbidity and mortality and recurrence after successful tumour resection. Intraoperative radiation therapy (IORT), which delivers targeted radiation to a tumour bed, is known to reduce local recurrence by directly killing tumour cells and modifying the tumour microenvironment. Methods Among 30 patients diagnosed with pancreatic cancer, 17 patients received IORT immediately after surgical resection. We investigated changes in the immune response induced by IORT by analysing the peritoneal fluid (PF) and blood of patients with and without IORT treatment after pancreatic cancer surgery. Further, we treated three pancreatic cell lines with PF to observe proliferation and activity changes. Results Levels of cytokines involved in the PI3K/SMAD pathway were increased in the PF of IORT-treated patients. Moreover, IORT-treated PF inhibited the growth, migration, and invasiveness of pancreatic cancer cells. Changes in lymphocyte populations in the blood of IORT-treated patients indicated an increased immune response. Conclusions Based on the characterisation and quantification of immune cells in the blood and cytokine levels in the PF, we conclude that IORT induced an anti-tumour effect by activating the immune response, which may prevent pancreatic cancer recurrence. Clinical trial registration NCT03273374 .
Biological effects of intraoperative radiation therapy: histopathological changes and immunomodulation in breast cancer patients
Intraoperative radiation therapy (IORT) delivers a single accelerated radiation dose to the breast tumor bed during breast-conserving surgery (BCS). The synergistic biologic effects of simultaneous surgery and radiation remain unclear. This study explores the cellular and molecular changes induced by IORT in the tumor microenvironment and its impact on the immune response modulation. Patients with hormone receptor (HR)-positive/HER2-negative, ductal carcinoma (DCIS), or early-stage invasive breast carcinoma undergoing BCS with margin re-excision were included. Histopathological evaluation and RNA-sequencing in the re-excision tissue were compared between patients with IORT (n=11) vs. non-IORT (n=11). Squamous metaplasia with atypia was exclusively identified in IORT specimens (63.6%, =0.004), mimicking DCIS. We then identified 1,662 differentially expressed genes (875 upregulated and 787 downregulated) between IORT and non-IORT samples. Gene ontology analyses showed that IORT was associated with the enrichment of several immune response pathways, such as inflammatory response, granulocyte activation, and T-cell activation ( <0.001). When only considering normal tissue from both cohorts, IORT was associated with intrinsic apoptotic signaling, response to gamma radiation, and positive regulation of programmed cell death ( <0.001). Using the xCell algorithm, we inferred a higher abundance of γδ T-cells, dendritic cells, and monocytes in the IORT samples. IORT induces histological changes, including squamous metaplasia with atypia, and elicits molecular alterations associated with immune response and intrinsic apoptotic pathways. The increased abundance of immune-related components in breast tissue exposed to IORT suggests a potential shift towards active immunogenicity, particularly immune-desert tumors like HR-positive/HER2-negative breast cancer.
Intraoperative radiation therapy (IORT) in pancreatic cancer
Despite the important improvements made in the fields of surgery, chemotherapy and radiation therapy, pancreatic cancer remains one of the most lethal malignancies. Improved outcomes with novel chemotherapy regimes led again to increased attention on the role of localized radiotherapy, since local tumor progression causes significant morbidity and mortality in patients. Even after resection local failure rates are as high as 50–80%. The immediate proximity to critical structures (bone marrow, spinal cord, kidneys, liver, and intestine) limits the dose of radiation that can be administered to the tumor bed with conventional external beam radiation therapy (EBRT). The intraoperative radiotherapy (IORT) appears to be an ideal therapeutic strategy for this disease, having the advantage of enabling the delivery of high doses of radiation to areas that are at risk for microscopic disease, saving critical organs and reducing the possibility of inducing radiotoxicity. This technique allows a theoretical increase in the radiation therapeutic index to tumor compared to the adjacent organs at risk (OAR). The aim of this review is to update and comment on IORT in the multidisciplinary management of pancreatic cancer.
Changes in peripheral immune cells after intraoperative radiation therapy in low-risk breast cancer
A detailed understanding of the interactions and the best dose-fractionation scheme of radiation to maximize antitumor immunity have not been fully established. In this study, the effect on the host immune system of a single dose of 20 Gy through intraoperative radiation therapy (IORT) on the surgical bed in low-risk breast cancer patients undergoing conserving breast cancer has been assessed. Peripheral blood samples from 13 patients were collected preoperatively and at 48 h and 3 and 10 weeks after the administration of radiation. We performed a flow cytometry analysis for lymphocyte subpopulations, natural killer cells (NK), regulatory T cells (Treg) and myeloid-derived suppressor cells (MDSCs). We observed that the subpopulation of NK CD56+high CD16+ increased significantly at 3 weeks after IORT (0.30–0.42%, P < 0.001), while no changes were found in immunosuppressive profile, CD4+CD25+Foxp3+Helios+ Treg cells, granulocytic MDSCs (G-MDSCs) and monocytic MDSCs (Mo-MDSCs). A single dose of IORT may be an effective approach to improve antitumor immunity based on the increase in NK cells and the non-stimulation of immunosuppressive cells involved in immune escape. These findings support future combinations of IORT with immunotherapy, if they are confirmed in a large cohort of breast cancer patients.
First clinical application of image-guided intraoperative electron radiation therapy with real time intraoperative dose calculation in recurrent rectal cancer: technical procedure
Intraoperative radiation therapy (IORT) is a radiation technique applying a single fraction with a high dose during surgery. We report the first abdomino-pelvic application of an image-guided intraoperative electron radiation therapy with intraoperative real time dose calculation based on the individual intraoperative patient anatomy. A patient suffering from locoregionally recurrent rectal cancer after treatment with neoadjuvant re-chemoradiation was chosen for this approach. After surgical removal of the recurrence, an adequate IORT applicator was placed as usual. A novel mobile imaging device (ImagingRing, MedPhoton) was positioned around the patient covering the region to be treated with the IORT-applicator in place. It allowed the acquisition of three-dimensional intraoperative cone-beam computed tomography images suitable for dose calculation using an automated scaling (heuristic object and head scatter as well as hardening corrections) of Hounsfield units. After image acquisition confirmed the correct applicator position, the images were transferred to our treatment planning system for intraoperative dose calculation. Treatment could be accomplished using the calculated dose distribution. We herein describe the details of the procedure including necessary adjustments in the typically used IORT equipment and work flow. We further discuss the pros and cons of this new approach generally overcoming a decade long limitation of IORT procedures as well as future perspectives regarding IORT treatments.
Portal Vein or Superior Mesenteric Vein Thrombosis with Dose-Escalated Radiation for Borderline or Locally Advanced Pancreatic Cancer
Purpose Portal vein and superior mesenteric vein thrombosis (PVT/SMVT) are potentially morbid complications of radiation dose–escalated local therapy for pancreatic cancer. We retrospectively reviewed records for patients treated with and without intraoperative radiation (IORT) to identify risk factors for PVT/SMVT. Methods Ninety-six patients with locally advanced or borderline resectable pancreatic adenocarcinoma received neoadjuvant therapy followed by surgical exploration from 2009 to 2014. Patients at risk for close or positive surgical margins received IORT boost to a biologically effective dose (BED10) > 100. Prognostic factors for PVT/SMVT were evaluated using competing risks regression. Results Median follow-up was 79 months for surviving patients. Fifty-six patients (58%) received IORT. Twenty-nine patients (30%) developed PVT/SMVT at a median time of 18 months. On univariate competing risks regression, operative blood loss and venous repair with a vascular interposition graft, but not IORT dose escalation or diabetes history, were significantly associated with PVT/SMVT. The development of thrombosis in the absence of recurrence was significantly associated with a longstanding diabetes history, post-neoadjuvant treatment CA19-9, and operative blood loss. All 4 patients who underwent both IORT and vascular repair with a graft developed PVT/SMVT. PVT/SMVT in the absence of recurrence is not associated with significantly worsened overall survival but led to frequent medical interventions. Conclusions Approximately 30% of patients who underwent neoadjuvant chemoradiation for PDAC developed PVT/SMVT a median of 18 months following surgery. This was significantly associated with venous reconstruction with vascular grafts, but not with escalating radiation dose. PVT/SMVT in the absence of recurrence was associated with significant morbidity.
Cerebellar liponeurocytoma: An updated follow-up of a case presenting histopathological and clinically aggressive features
Cerebellar liponeurocytoma is a rare tumor recently included by World Health Organization in the classification of brain tumors as a separate clinicopathological entity separate from medulloblastoma. However, because of the rarity of the tumor, the natural history of the tumor is still not yet been defined. We report a patient with cerebellar liponeurocytoma with unusual clinical and pathological aggressive features. This patient suggests the possible existence of different histological grades of liponeurocytoma and its possible progression to a malignant grade.
Low-Energy X-Ray Intraoperative Radiation Therapy (Lex-IORT) for Resected Brain Metastases: A Single-Institution Experience
Background: Resection followed by local radiation therapy (RT) is the standard of care for symptomatic brain metastases. However, the optimal technique, fractionation scheme and dose are still being debated. Lately, low-energy X-ray intraoperative RT (lex-IORT) has been of increasing interest. Method: Eighteen consecutive patients undergoing BM resection followed by immediate lex-IORT with 16–30 Gy applied to the spherical applicator were retrospectively analyzed. Demographic, RT-specific, radiographic and clinical data were reviewed to evaluate the effectiveness and safety of IORT for BM. Descriptive statistics and Kaplan–Meyer analysis were applied. Results: The mean follow-up time was 10.8 months (range, 0–39 months). The estimated local control (LC), distant brain control (DBC) and overall survival (OS) at 12 months post IORT were 92.9% (95%-CI 79.3–100%), 71.4% (95%-CI 50.2–92.6%) and 58.0% (95%-CI 34.1–81.9%), respectively. Two patients developed radiation necrosis (11.1%) and wound infection (CTCAE grade III); both had additional adjuvant treatment after IORT. For five patients (27.8%), the time to the start or continuation of systemic treatment was ≤15 days and hence shorter than wound healing and adjuvant RT would have required. Conclusion: In accordance with previous series, this study demonstrates the effectiveness and safety of IORT in the management of brain metastases despite the small cohort and the retrospective characteristic of this analysis.
Cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy and intraoperative radiation therapy in the management of gastric cancer: a 10-year single center experience
Background The rationale behind the use of HIPEC involves targeted elimination of microscopic peritoneal metastasis, a common route for GCa dissemination, thereby improving the overall survival and reducing recurrences. Moreover, the reasoning behind the use of IORT is enhanced loco-regional control and, therefore, reducing recurrence rates. Methods From February 2013 to June 2023, all GCa patients who underwent HIPEC plus IORT during surgery were included in this study. Median overall survival (OS) and disease-free (DFS) survival were used to evaluate the efficacy of this treatment strategy amongst GCa patients, along with the rate of occurrence and severity of post-operative complications associated with this treatment strategy. Results The median OS and DFS were 63 and 87 months, respectively. More than one-third of the patients in our cohort did not develop any post-operative complications. In patients who developed post-operative complications, the median number of post-operative complications was 1 (IQR 1–2). Most encountered complications were Clavien-Dindo (CD) grade II complications (33.33%) and no in-hospital mortality was observed. Conclusions This complex, multimodal treatment strategy results in a significantly prolonged OS and DFS when compared to other treatment strategies for gastric cancer patients, with no added morbidity or mortality.