Quantifying the impact of SpaceOAR hydrogel on inter-fractional rectal and bladder dose during 0.35 T MR-guided prostate adaptive radiotherapy.

Purpose: To investigate the impact of rectal spacing on inter-fractional rectal and bladder dose and the need for adaptive planning in prostate cancer patients undergoing SBRT with a 0.35 T MRI-Linac.

Materials And Methods: We evaluated and compared SBRT plans from prostate cancer patients with and without rectal spacer who underwent treatment on a 0.

Deep learning-based synthetic CT generation for MR-only radiotherapy of prostate cancer patients with 0.35T MRI linear accelerator.

Purpose: To develop a deep learning model to generate synthetic CT for MR-only radiotherapy of prostate cancer patients treated with 0.35 T MRI linear accelerator.

Materials And Methods: A U-NET convolutional neural network was developed to translate 0.

Prospective Randomized Trial of Prone Accelerated Intensity Modulated Breast Radiation Therapy With a Daily Versus Weekly Boost to the Tumor Bed.

Purpose: To report the results of a prospective randomized trial comparing a daily versus weekly boost to the tumor cavity during the course of accelerated radiation to the breast with patients in the prone position.

Methods And Materials: From 2009 to 2012, 400 patients with stage 0 to II breast cancer who had undergone segmental mastectomy participated in an institutional review board-approved trial testing prone breast radiation therapy to 40.5 Gy in 15 fractions 5 d/wk to the whole breast, after randomization to a concomitant daily boost to the tumor bed of 0.

Breast, chest wall, and nodal irradiation with prone set-up: Results of a hypofractionated trial with a median follow-up of 35 months.

Purpose: To test clinical feasibility, safety, and toxicity of prone hypofractionated breast, chest wall, and nodal radiation therapy.

Methods And Materials: Following either segmental or total mastectomy with axillary node dissection, patients were treated in an institutional review board-approved prospective trial of prone radiation therapy to the breast, chest wall, and supraclavicular and level III axillary lymph nodes. A dose of 40.

Use of a Flexible Inflatable Multi-Channel Applicator for Vaginal Brachytherapy in the Management of Gynecologic Cancer.

Introduction: Evaluate use of novel multi-channel applicator (MC) Capri™ to improve vaginal disease coverage achievable by single-channel applicator (SC) and comparable to Syed plan simulation.

Materials And Methods: Twenty-eight plans were evaluated from four patients with primary or recurrent gynecologic cancer in the vagina. Each received whole pelvis radiation, followed by three weekly treatments using HDR brachytherapy with a 13-channel MC.

Prone breast intensity modulated radiation therapy: 5-year results.

Purpose: To report the 5-year results of a technique of prone breast radiation therapy delivered by a regimen of accelerated intensity modulated radiation therapy with a concurrent boost to the tumor bed.

Methods And Materials: Between 2003 and 2006, 404 patients with stage I-II breast cancer were prospectively enrolled into 2 consecutive protocols, institutional trials 03-30 and 05-181, that used the same regimen of 40.5 Gy/15 fractions delivered to the index breast over 3 weeks, with a concomitant daily boost to the tumor bed of 0.

Comparison of Acute and Late Toxicity of Two Regimens of 3- and 5-Week Concomitant Boost Prone IMRT to Standard 6-Week Breast Radiotherapy.

Purpose: Limited information is available comparing toxicity of accelerated radiotherapy (RT) to that of standard fractionation RT for early stage breast cancer. We report early and late toxicities of two prone regimens of accelerated intensity-modulated radiation therapy (IMRT) with a concomitant boost (CB) to the tumor bed delivered over 3 or 5 weeks as compared to standard 6 week RT with a sequential electron boost.

Methods: From 2/2003 to 12/2007, 169 consecutive patients with Stage I-II breast cancer were offered the choice to undergo prone RT with either: a 6-week standard RT regimen of 46 Gy/23 fractions (fx) to the whole breast (WB), followed by a14 Gy sequential boost (SB) to the tumor bed (6wSB), a 5-week regimen of 50 Gy to WB with an IMRT CB of 6.

Breast radiotherapy in the prone position primarily reduces the maximum out-of-field measured dose to the ipsilateral lung.

Purpose: To quantify the potential advantages of prone position breast radiotherapy in terms of the radiation exposure to out-of-field organs, particularly, the breast or the lung. Several dosimetric studies have been reported, based on commercial treatment planning software (TPS). These TPS approaches are not, however, adequate for characterizing out-of-field doses.

Prone accelerated partial breast irradiation after breast-conserving surgery: compliance to the dosimetry requirements of RTOG-0413.

Purpose: The dosimetric results from our institution's trials of prone accelerated partial breast irradiation are compared with the dosimetric requirements of RTOG-0413.

Methods And Materials: Trial 1 and Trial 2 are 2 consecutive trials of prone-accelerated partial breast irradiation. Eligible for both trials were stage I breast cancer patients with negative margins after breast-conserving surgery.

Prone accelerated partial breast irradiation after breast-conserving surgery: five-year results of 100 patients.

Purpose: To report the 5-year results of a prospective trial of three-dimensional conformal external beam radiotherapy (3D-CRT) to deliver accelerated partial breast irradiation in the prone position.

Methods And Materials: Postmenopausal patients with Stage I breast cancer with nonpalpable tumors <2 cm, negative margins and negative nodes, positive hormone receptors, and no extensive intraductal component were eligible. The trial was offered only after eligible patients had refused to undergo standard whole-breast radiotherapy.

Dose to craniofacial region through portal imaging of pediatric brain tumors.

The purpose of this study was to determine dose to the planning target volume (PTV) and organs at risk (OARs) from portal imaging (PI) of the craniofacial region in pediatric brain tumor patients treated with intensity-modulated radiation therapy (IMRT). Twenty pediatric brain tumor patients were retrospectively studied. Each received portal imaging of treatment fields and orthogonal setup fields in the craniofacial region.

TGFβ1 inhibition increases the radiosensitivity of breast cancer cells in vitro and promotes tumor control by radiation in vivo.

Purpose: To determine whether inhibition of TGFβ signaling prior to irradiation sensitizes human and murine cancer cells in vitro and in vivo.

Experimental Design: TGFβ-mediated growth and Smad phosphorylation of MCF7, Hs578T, MDA-MB-231, and T47D human breast cancer cell lines were examined and correlated with clonogenic survival following graded radiation doses with and without pretreatment with LY364947, a small molecule inhibitor of the TGFβ type I receptor kinase. The DNA damage response was assessed in irradiated MDA-MB-231 cells pretreated with LY364947 in vitro and LY2109761, a pharmacokinetically stable inhibitor of TGFβ signaling, in vivo.

Prone hypofractionated whole-breast radiotherapy without a boost to the tumor bed: comparable toxicity of IMRT versus a 3D conformal technique.

Purpose: We report a comparison of the dosimetry and toxicity of three-dimensional conformal radiotherapy (3D-CRT) vs. intensity-modulated radiotherapy (IMRT) among patients treated in the prone position with the same fractionation and target of the hypofractionation arm of the Canadian/Whelan trial.

Methods And Materials: An institutional review board-approved protocol identified a consecutive series of early-stage breast cancer patients treated according to the Canadian hypofractionation regimen but in the prone position.

Prospective study of cone-beam computed tomography image-guided radiotherapy for prone accelerated partial breast irradiation.

Purpose: To report setup variations during prone accelerated partial breast irradiation (APBI).

Methods: New York University (NYU) 07-582 is an institutional review board-approved protocol of cone-beam computed tomography (CBCT) to deliver image-guided ABPI in the prone position. Eligible are postmenopausal women with pT1 breast cancer excised with negative margins and no nodal involvement.

The role of a prone setup in breast radiation therapy.

Most patients undergoing breast conservation therapy receive radiotherapy in the supine position. Historically, prone breast irradiation has been advocated for women with large pendulous breasts in order to decrease acute and late toxicities. With the advent of CT planning, the prone technique has become both feasible and reproducible.

Decreasing temporal lobe dose with five-field intensity-modulated radiotherapy for treatment of pituitary macroadenomas.

Purpose: To compare temporal lobe dose delivered by three pituitary macroadenoma irradiation techniques: three-field three-dimensional conformal radiotherapy (3D-CRT), three-field intensity-modulated radiotherapy (3F IMRT), and a proposed novel alternative of five-field IMRT (5F IMRT).

Methods And Materials: Computed tomography-based external beam radiotherapy planning was performed for 15 pituitary macroadenoma patients treated at New York University between 2002 and 2007 using: 3D-CRT (two lateral, one midline superior anterior oblique [SAO] beams), 3F IMRT (same beam angles), and 5F IMRT (same beam angles with additional right SAO and left SAO beams). Prescription dose was 45 Gy.

Interfraction and intrafraction setup variability for prone breast radiation therapy.

Purpose: To report the interfraction and intrafraction setup variation for prone breast radiotherapy and to determine an appropriate clinical tumor volume (CTV) to planning target volume (PTV)_ margin to account for motion and positional uncertainties.

Methods And Materials: Ten consecutive patients were prospectively enrolled in a protocol of accelerated, hypofractionated prone breast irradiation. Portal images were acquired using an electronic portal imaging device in cine mode.

Fractionated but not single-dose radiotherapy induces an immune-mediated abscopal effect when combined with anti-CTLA-4 antibody.

Purpose: This study tested the hypothesis that the type of dose fractionation regimen determines the ability of radiotherapy to synergize with anti-CTLA-4 antibody.

Experimental Design: TSA mouse breast carcinoma cells were injected s.c.

Characterization of the transmission of the Elekta Stereotactic Body Frame (ESBF) and accounting for it during treatment planning.

The purpose of this study was to measure the transmission of the Elekta Stereotactic Body Frame (ESBF) and treatment table, to calculate the transmission of the frame in the Eclipse Treatment Planning System (TPS) using analytical anisotropic algorithm (AAA), and to demonstrate a simple method of accounting for this transmission in treatment planning. A solid water body phantom was imaged inside the ESBF and planned with multiple 3D-CRT fields using AAA using both 6-MV and 16-MV energies. In the first set of plans, the frame and table were included in the "Body" contour and, therefore, used in the dose calculations.

Coverage of axillary lymph nodes in supine vs. prone breast radiotherapy.

Purpose: To compare the dosimetry of target and normal tissue when tangents with the breast tissue were applied in a subset of breast cancer patients who had undergone computed tomography (CT) planning both supine and prone.

Methods And Materials: The CT images of 20 patients who had undergone simulation in supine and prone positions were used for planning. The axillary lymph node regions (level I-III), breast tissue, tumor bed, heart, and bilateral lungs were manually contoured.