Asal Rahimi

p16 Not a Prognostic Marker for Hypopharyngeal Squamous Cell Carcinoma

OBJECTIVE To investigate the prognostic significance of p16 in patients with hypopharyngeal squamous cell carcinoma (HPSCC) and to evaluate the relationship between p16 and human papillomavirus (HPV). Unlike in oropharyngeal SCC (OPSCC), the prognostic significance of p16 in HPSCC and its association with HPV is unclear. DESIGN Retrospective medical chart review. SETTING University tertiary referral center. PATIENTS A total of 27 patients with HPSCC treated with definitive radiation therapy between 2002 and 2011 whose tissue was available for immunohistochemical analysis. INTERVENTIONS Twenty-two patients were treated with chemoradiation, and 5 with radiation alone. All tumor biopsy specimens were analyzed for p16 and, when sufficient tissue was available, for HPV DNA. MAIN OUTCOME MEASURES Overall survival (OS), locoregional control (LRC), disease-free survival (DFS), and laryngoesophageal dysfunction-free survival (LEDFS) were analyzed according to p16 status. RESULTS Findings for p16 were positive in 9 tumors and negative in 18 tumors. Median follow-up was 29.3 months. There was no significant difference in OS, LRC, DFS, or LEDFS for patients with p16-positive vs p16-negative tumors. Only 1 of the 19 tumors tested for HPV was found to be HPV positive. When used as a test for HPV, p16 had a positive predictive value of 17%. CONCLUSIONS In contrast to OPSCC, p16 expression in patients with HPSCC had a low positive predictive value for HPV and did not predict improved OS, LRC, DFS, or LEDFS. Thus, for HPSCC, p16 is not a prognostic biomarker. Caution must be taken when extrapolating the prognostic significance of p16 in patients with OPSCC to patients with head and neck SCC of other subsites.

Carbon ion radiotherapy: A review of clinical experiences and preclinical research, with an emphasis on DNA damage/repair

Compared to conventional photon-based external beam radiation (PhXRT), carbon ion radiotherapy (CIRT) has superior dose distribution, higher linear energy transfer (LET), and a higher relative biological effectiveness (RBE). This enhanced RBE is driven by a unique DNA damage signature characterized by clustered lesions that overwhelm the DNA repair capacity of malignant cells. These physical and radiobiological characteristics imbue heavy ions with potent tumoricidal capacity, while having the potential for simultaneously maximally sparing normal tissues. Thus, CIRT could potentially be used to treat some of the most difficult to treat tumors, including those that are hypoxic, radio-resistant, or deep-seated. Clinical data, mostly from Japan and Germany, are promising, with favorable oncologic outcomes and acceptable toxicity. In this manuscript, we review the physical and biological rationales for CIRT, with an emphasis on DNA damage and repair, as well as providing a comprehensive overview of the translational and clinical data using CIRT.

Ultrasound-Guided Placement of Gold Fiducial Markers for Stereotactic Partial-Breast Irradiation

OBJECTIVE A novel technique of placing gold fiducial markers in the breast using ultrasound guidance was developed and performed in 51 of 55 consecutive postlumpectomy patients enrolled in a phase I dose escalation trial of accelerated partial-breast irradiation (APBI) using robotic-based stereotactic body radiation therapy (SBRT). CONCLUSION All 51 postoperative patients underwent successful fiducial placement without complications. Our technique of placing gold fiducial markers in proximity to the seroma cavity is considered safe and effective for breast cancer patients being treated with APBI using robotic-based SBRT.

Radiation recall precipitated by iodinated nonionic contrast

Radiation recall is a rare, poorly understood clinical syndrome characterized by an acute inflammatory reaction in the distribution of prior radiation exposure. It is most commonly precipitated by chemotherapy, but noncytotoxic medications have also been described as triggering agents.1,2 Radiation recall most commonly presents as dermatitis (RRD) involving the skin but canmanifest in deep tissues, including critical structures.3 Herein, we report a case of RRD precipitated by nonionic contrast.

Deep inspiration breathhold for left-sided breast cancer patients with unfavorable cardiac anatomy requiring internal mammary nodal irradiation

PURPOSE The purpose of this study was to evaluate the utility of moderate deep inspiration breathhold (mDIBH) in reducing heart exposure in left breast cancer patients who have unfavorable cardiac anatomy and need internal mammary lymph node (IMLN) radiation therapy (RT). METHODS AND MATERIALS We used maximum heart distance (MHD), defined as the maximum distance of the heart within the treatment field, >1 cm as a surrogate for unfavorable cardiac anatomy. Twenty-two left breast cancer patients with unfavorable cardiac anatomy requiring IMLN-RT underwent free-breathing (FB) and mDIBH computed tomography simulation and planning. Three-dimensional partially wide tangents (3D-PWTs) and intensity modulated RT plans were generated. Dose-volume histograms were used to compare heart and lung dosimetric parameters. Duration of treatment delivery was recorded for all fractions. RESULTS MHD decreased significantly in mDIBH scans. mDIBH significantly reduced mean heart dose (222.7 vs 578.4 cGy; P < .0001) and percentage of left lung receiving doses ≥20 Gy (V20; 31.93 vs 38.41%; P = .0006) in both 3D-PWT and intensity modulated RT plans. The change in MHD after breathhold reliably predicted mean heart dose reduction after mDIBH. Radiation was effectively delivered in 11.31 ± 3.40 minutes with an average of 10.06 ± 2.74 breathholds per fraction. CONCLUSIONS mDIBH is efficient and can effectively decrease mean heart dose in patients with unfavorable cardiac anatomy who need IMLN-RT, thus simplifying planning and delivery for them. The reduction in mean heart dose is proportional to the reduction in maximum heart distance.

Review of breast screening: Toward clinical realization of microwave imaging

&NA; Microwave imaging (MI) technology has come a long way to introduce a noninvasive, inexpensive, fast, convenient, and safe screening tool for clinical breast monitoring. However, there is a niche between the existing understanding of MI by engineers versus clinicians. Our manuscript targets that niche and highlights the state of the art in MI technology compared to the existing breast cancer detection modalities (mammography, ultrasound, molecular imaging, and magnetic resonance). The significance of our review article is in consolidation of up‐to‐date breast clinician views with the practical needs and engineering challenges of a novel breast screening modality. We summarize breast tissue abnormalities and highlight the benefits as well as potential drawbacks of the MI as a cancer detection methodology. Our goal is to present an article that MI researchers as well as practitioners in the field can use to assess the viability of the MI technology as a competing or complementary modality to the existing means of breast cancer screening.

Primary synovial chondromatosis of the subtalar joint: case report and review of the literature

Primary synovial chondromatosis is a rare benign condition of uncertain etiology manifested by synovial proliferation. In the radiology literature, there is only 1 prior case report of primary synovial chondromatosis involving the subtalar joint with only partial description of the imaging appearance. We present a 28-year-old female with primary synovial chondromatosis of the subtalar joint and conduct a literature review of the imaging features of primary synovial chondromatosis presenting in the feet.

Electronic Medical Record–Based Radiation Oncology Toxicity Recording Instrument Aids Benchmarking and Quality Improvement in the Clinic

PURPOSE The on-treatment visit (OTV) for radiation oncology is essential for patient management. Radiation toxicities recorded during the OTV may be inconsistent because of the use of free text and the lack of treatment site-specific templates. We developed a radiation oncology toxicity recording instrument (ROTOX) in a health system electronic medical record (EMR). Our aims were to assess improvement in documentation of toxicities and to develop clinic toxicity benchmarks. METHODS A ROTOX that was based on National Cancer Institute Common Terminology Criteria for Adverse Events (version 4.0) with flow-sheet functionality was developed in the EMR. Improvement in documentation was assessed at various time intervals. High-grade toxicities (ie, grade ≥ 3 by CTCAE) by site were audited to develop benchmarks and to track nursing and physician actions taken in response to these. RESULTS A random sample of OTV notes from each clinic physician before ROTOX implementation was reviewed and assigned a numerical document quality score (DQS) that was based on completeness and comprehensiveness of toxicity grading. The mean DQS improved from an initial level of 41% to 99% (of the maximum possible DQS) when resampled at 6 months post-ROTOX. This high-level DQS was maintained 3 years after ROTOX implementation at 96% of the maximum. For months 7 to 9 after implementation (during a 3-month period), toxicity grading was recorded in 4,443 OTVs for 698 unique patients; 107 episodes of high-grade toxicity were identified during this period, and toxicity-specific intervention was documented in 95%. CONCLUSION An EMR-based ROTOX enables consistent recording of treatment toxicity. In a uniform sample of patients, local population toxicity benchmarks can be developed, and clinic response can be tracked.

New Techniques for Irradiating Early Stage Breast Cancer: Stereotactic Partial Breast Irradiation

Several improvements in breast cancer radiation delivery have been realized using new techniques over the past several decades. As an example, for early stage disease, there has been active investigation of partial breast irradiation (PBI) vs whole breast irradiation. Although still investigational, PBI reduces the treatment volumes, doses to organs at risk, and may improve cosmesis. Over the past 2 decades PBI has been delivered via interstitial brachytherapy, intracavitary brachytherapy, intraoperative radiation therapy, or 3-dimensional external beam radiation therapy. More recently, there has been growing evidence that supports stereotactic body radiation therapy as a safe and effective new treatment for early stage breast cancer. This article describes this new treatment opportunity and reviews the emerging data of stereotactic partial breast irradiation.

SU-F-T-650: The Comparison of Robotic Partial Breast Stereotactic Irradiation Using MLC Vs. Iris Cone

PURPOSE To evaluate the dosimetric impact on treatment planning for partial breast stereotactic irradiation using Cyberknife with MLC versus Iris Cone. METHODS Ten patients whom underwent lumpectomy for DCIS or stage I invasive non-lobular epithelial breast cancer were included in this study. All patients were previously treated on the Cyberknife using Iris cone with the prescription dose of 37.5Gy in 5 fractions covering at least 95% of PTV on our phase I SBRT 5 fraction partial breast irradiation trial. Retrospectively, treatment planning was performed and compared using the new Cyberknife M6 MLC system for each patient. Using the same contours and critical organ constraints for both MLC and Iris cone plans, the dose on target and critical organs were analyzed accordingly. RESULTS Dose to critical organs such as ipsilateral lung, contralateral lung, heart, skin, ipsilateral breast, and rib were analyzed, as well as conformity index and high dose spillage of the target area. In 9 of 10 patients, the MLC plans had less total ipsilateral breast volume encompassing the 50% prescription isodose (mean:22.3±8.2% MLC vs. 31.6±8.0 Iris, p=0.00014) .The MLC plans mean estimated treatment delivery time was significantly less than the Iris plans (51±3.9min vs. 56.2±9min, p=0.03) Both MLC and Iris cone plans were able to meet all dose constraints and there was no statistical difference between those dose constraints. CONCLUSION Both MLC and Iris Cone can deliver conformal dose to a partial breast target and satisfy the dose constraints of critical organs. The new Cyberknife with MLC can deliver a more conformal dose in the lower dose region and spare more ipsilateral breast tissue to the 50% prescription isodose. The treatment time for partial breast SBRT plans was also reduced using MLC. Project receives research support from Accuray Inc.