Highs and Lows of Spatially Fractionated Radiation Therapy: Dosimetry and Clinical Outcomes.

Objectives: Spatially fractionated radiation therapy (SFRT) intentionally delivers a heterogeneous dose distribution characterized by alternating regions of high and low doses throughout a tumor. This modality may enhance response to subsequent whole tumor radiation in bulky and radioresistant lesions that are historically less responsive to conventional radiation doses alone. The current study presents a single institution experience with modern era SFRT using predominantly a volumetric modulated arc therapy (VMAT) lattice technique.

Increased Occurrence of Malignancy Before and after Chemoradiation for Anal Squamous Cell Carcinoma: A Multi-Institutional Analysis.

Background: Anal squamous cell carcinoma (ASCC) is a rare cancer with increased occurrence of multiple cancers before and after the ASCC diagnosis. However, there is limited data on this aspect. This multi-institutional analysis aimed to define the occurrence of malignancies before and after ASCC, time trends, impact on survival, and identify prognostic factors.

A Prospective Pilot Study of Pencil Beam Scanning Proton Radiation Therapy as a Component of Trimodality Therapy for Esophageal Cancer.

Purpose: To evaluate the safety and efficacy of pencil beam scanning (PBS) proton radiation therapy (RT) in trimodality therapy for esophageal cancer.

Methods And Materials: This prospective pilot study was planned to accrue 30 patients with locally advanced esophageal or gastroesophageal junction carcinoma medically suitable for chemoradiation therapy (CRT) followed by esophagectomy. PBS proton RT consisted of 25 fractions, 50 Gy to tumor + 1 cm and 45 Gy to a 3.

Myxofibrosarcoma: Outcomes, Prognostic Factors, and Role of Neoadjuvant Radiation Therapy.

Purpose: Myxofibrosarcoma (MFS) is a subtype of soft tissue sarcoma with a highly infiltrative growth pattern that leads to a higher risk of inadvertent positive surgical margins and local relapse. Poorly defined tumor margins also pose a challenge for radiation therapy (RT) planning, in terms of treatment volumes and administration of pre- versus postoperative RT. This study aims to evaluate local control and patterns of recurrence in patients with MFS treated with neoadjuvant RT followed by definitive surgical excision.

Automated target placement for VMAT lattice radiation therapy: enhancing efficiency and consistency.

. An algorithm was developed for automated positioning of lattice points within volumetric modulated arc lattice radiation therapy (VMAT LRT) planning. These points are strategically placed within the gross tumor volume (GTV) to receive high doses, adhering to specific separation rules from adjacent organs at risk (OARs).

Prospective Correlation of Magnetic Resonance Tumor Regression Grade With Pathologic Outcomes in Total Neoadjuvant Therapy for Rectal Adenocarcinoma.

Purpose: Total neoadjuvant therapy (TNT) is a newly established standard treatment for rectal adenocarcinoma. Current methods to communicate magnitudes of regression during TNT are subjective and imprecise. Magnetic resonance tumor regression grade (MR-TRG) is an existing, but rarely used, regression grading system.

Clinical aspects of spatially fractionated radiation therapy treatments.

Purpose: To provide clinical guidance for centers wishing to implement photon spatially fractionated radiation therapy (SFRT) treatments using either a brass grid or volumetric modulated arc therapy (VMAT) lattice approach.

Methods: We describe in detail processes which have been developed over the course of a 3-year period during which our institution treated over 240 SFRT cases. The importance of patient selection, along with aspects of simulation, treatment planning, quality assurance, and treatment delivery are discussed.

Comparing Oncologic Outcomes and Toxicity for Combined Modality Therapy vs. Carbon-Ion Radiotherapy for Previously Irradiated Locally Recurrent Rectal Cancer.

No standard treatment paradigm exists for previously irradiated locally recurrent rectal cancer (PILRRC). Carbon-ion radiotherapy (CIRT) may improve oncologic outcomes and reduce toxicity compared with combined modality therapy (CMT). Eighty-five patients treated at Institution A with CIRT alone (70.

Dosimetric comparison between proton beam therapy, intensity modulated radiation therapy, and 3D conformal therapy for soft tissue extremity sarcoma.

Purpose/objectives: Proton beam therapy (PBT) may provide a dosimetric advantage in sparing soft tissue and bone for selected patients with extremity soft sarcoma (eSTS). We compared PBT with photons plans generated using intensity-modulated radiotherapy (IMRT) and three-dimensional conformal radiotherapy (3D-CRT).

Materials/methods: Seventeen patients previously treated with pencil beam scanning PBT were included in this study.

Association of Radiotherapy Duration With Clinical Outcomes in Patients With Esophageal Cancer Treated in NRG Oncology Trials: A Secondary Analysis of NRG Oncology Randomized Clinical Trials.

Importance: For many types of epithelial malignant neoplasms that are treated with definitive radiotherapy (RT), treatment prolongation and interruptions have an adverse effect on outcomes.

Objective: To analyze the association between RT duration and outcomes in patients with esophageal cancer who were treated with definitive chemoradiotherapy (CRT).

Design, Setting, And Participants: This study was an unplanned, post hoc secondary analysis of 3 prospective, multi-institutional phase 3 randomized clinical trials (Radiation Therapy Oncology Group [RTOG] 8501, RTOG 9405, and RTOG 0436) of the National Cancer Institute-sponsored NRG Oncology (formerly the National Surgical Adjuvant Breast and Bowel Project, RTOG, and Gynecologic Oncology Group).

Pragmatic, Prospective Comparative Effectiveness Trial of Carbon Ion Therapy, Surgery, and Proton Therapy for the Management of Pelvic Sarcomas (Soft Tissue/Bone) Involving the Bone: The PROSPER Study Rationale and Design.

Surgical treatment of pelvic sarcoma involving the bone is the standard of care but is associated with several sequelae and reduced functional quality of life (QOL). Treatment with photon and proton radiotherapy is associated with relapse. Carbon ion radiotherapy (CIRT) may reduce both relapse rates and treatment sequelae.

Risk stratification of postoperative cardiopulmonary toxicity after trimodality therapy for esophageal cancer.

Purpose/objective: Postoperative toxicity for esophageal cancer impacts patient quality of life and potentially overall survival (OS). We studied whether patient and toxicity parameters post-chemoradiation therapy predict for post-surgical cardiopulmonary total toxicity burden (CPTTB) and whether CPTTB was associated with short and long-term outcomes.

Materials/methods: Patients had biopsy-proven esophageal cancer treated with neoadjuvant chemoradiation and esophagectomy.

Multiagent Chemotherapy Followed by Stereotactic Body Radiotherapy Versus Conventional Radiotherapy for Resected Pancreas Cancer.

Background And Purpose: Chemotherapy followed by margin-negative resection (R0) is the treatment of choice for patients with localized pancreatic ductal adenocarcinoma (PDAC). Neoadjuvant multiagent chemotherapy (MAC) or MAC then radiotherapy (RT) may optimize surgical candidacy. The purpose of this study was to compare pathologic outcomes of MAC followed by conventionally fractionated radiotherapy (CRT) versus stereotactic body radiotherapy (SBRT) for patients with resected PDAC.

FDG-PET Predicts Neoadjuvant Therapy Response and Survival in Borderline Resectable/Locally Advanced Pancreatic Adenocarcinoma.

Background: Neoadjuvant therapy (NAT) is used in borderline resectable/locally advanced (BR/LA) pancreatic ductal adenocarcinoma (PDAC). Anatomic imaging (CT/MRI) poorly predicts response, and biochemical (CA 19-9) markers are not useful (nonsecretors/nonelevated) in many patients. Pathologic response highly predicts survival post-NAT, but is only known postoperatively.

Re-resection of Microscopically Positive Margins Found on Intraoperative Frozen Section Analysis Does Not Result in a Survival Benefit in Patients Undergoing Surgery and Intraoperative Radiation Therapy for Locally Recurrent Rectal Cancer.

Background: Intraoperative frozen-section analysis provides real-time margin resection status that can guide intraoperative decisions made by the surgeon and radiation oncologist. For patients with locally recurrent rectal cancer undergoing surgery and intraoperative radiation therapy, intraoperative re-resection of positive margins to achieve negative margins is common practice.

Objective: This study aimed to assess whether re-resection of positive margins found on intraoperative frozen-section analysis improves oncologic outcomes.

A Dosimetric Comparison of Lattice, Brass, and Proton Grid Therapy Treatment Plans.

Purpose: Our purpose was to dosimetrically compare volumetric modulated arc therapy (VMAT) lattice radiation therapy (LRT), brass, and proton grid therapy planning techniques and suggest potential clinical applications for each.

Methods And Materials: Four plans delivering 20 Gy in 1 fraction were created for each of 22 patients. Brass and proton grid plans used a single static field and the same beam angle.

N064A (Alliance): Phase II Study of Panitumumab, Chemotherapy, and External Beam Radiation in Patients with Locally Advanced Pancreatic Adenocarcinoma.

Background: This North Central Cancer Treatment Group (NCCTG) N064A (Alliance) phase II trial evaluated upfront chemoradiotherapy incorporating the EGFR inhibitor panitumumab, followed by gemcitabine and panitumumab for unresectable, non-metastatic pancreatic cancer.

Methods: The treatment consisted of fluoropyrimidine and panitumumab given concurrently with radiotherapy followed by gemcitabine and panitumumab for 3 cycles followed by maintenance panitumumab. The primary endpoint was the 12-month overall survival (OS) rate and secondary endpoints included confirmed response rate (RR), OS, progression-free survival (PFS), and adverse events.

Comparison of Oncologic Outcomes and Treatment-Related Toxicity of Carbon Ion Radiotherapy and En Bloc Resection for Sacral Chordoma.

Importance: Maximal resection is the preferred management for sacral chordomas but can be associated with unacceptable morbidity. Outcomes with radiotherapy are poor. Carbon ion radiotherapy (CIRT) is being explored as an alternative when surgery is not preferred.