Abstract P1-10-20: A multi-center trial of intra-operative electronic brachytherapy during breast conservation surgery for early stage breast cancer: Early results of unplanned boost participants

Objective

To assess the safety and efficacy of single-fraction, intra-operative radiation therapy (IORT) delivered as a boost using the Xoft® Axxent® Electronic Brachytherapy System® (eBx®) immediately following surgical resection for treatment of early stage breast cancer.

Methods

This phase 4, open-label, single-arm, prospective, non-randomized trial is still enrolling participants and is currently being conducted at 26 hospitals in the USA (25) and Portugal (1). 878 participants with biopsy-proven ductal carcinoma in situ (DCIS) or invasive ductal carcinoma who met the inclusion criteria underwent lumpectomy followed by single-fraction IORT to the lumpectomy cavity. Briefly, a small, presterilized lead shield piece was placed on the chest wall to reduce the dose to the ribs, and then a balloon applicator, suitable to the surgical bed, was placed in the lumpectomy cavity and inflated with saline (30-75 cc); skin was temporarily closed over the balloon and ultrasound was used to confirm a balloon surface-to-skin distance ≥ 1.0 cm. The Xoft System was used to deliver the 20 Gy dose at the balloon applicator surface. The balloon was deflated, lead shield and balloon removed and the surgical site sutured. Upon the presence of additional risk factors, 37 participants subsequently received whole breast radiation therapy (WBRT); thus, these participants received an unplanned IORT boost and were removed from the primary analysis but will continue to be followed for the duration of the 10-year study. Cosmesis (Harvard Scale) was assessed in this subset of participants. The primary outcome for the main trial is recurrence of ipsilateral breast tumor at 5 years. Trial Registry: ClinicalTrials.gov; Identifier: NCT01644669.

Early Findings

37 boost participants received WBRT (up to 50 Gy) after IORT (36 received the prescribed 20 Gy dose; one received 14 Gy). Mean follow-up time was 430 days (range 13-1119). Mean age at IORT was 62 years (range 45-78). Boost participants had either DCIS (N=5) or invasive ductal carcinoma (N=32). The DCIS nuclear grade was high (N=3), intermediate (N=1), or low (N=1). Invasive cancers were Grade 1 (N=15), 2 (N=10), 3 (N=6), or unknown (N=1). 29 participants had T1, 3 had T2, and 5 had Tis lesions. Mean tumor size was 13.04 ± 10.26 mm. For the two participants who have reached 3-year follow-up, cosmesis was excellent (N=1) and fair (N=1). For the six participants who have reached 2-year follow-up, cosmesis was excellent (N=4), good (N=1), and fair (N=1). There was one serious adverse event with a Grade 3 for skin necrosis. The most frequent side effects were seroma (10%), edema (9%), pain (9%), erythema (6%), and induration (5%). There have been no deaths, recurrences, or new primary tumors among the boost participants to date.

Conclusions

Early results from this multi-center trial suggest that IORT as a tumor-bed boost using the Xoft Axxent eBx System at the time of breast conservation surgery is safe and has low morbidity. To date, the majority of participants receiving an unplanned IORT boost have had excellent to good cosmetic results and the majority of adverse events have been low-grade.

Funding

Funded by Xoft, Inc., a subsidiary of iCAD, Inc.

Citation Format: Syed AMN, Chang H, Schwartzberg B, Bremner A, Boylan S, Lopez-Penalver C, Vito C, Davis M, Dooley W, Chakravarthy AB, Coomer C, Proulx G, Golder S, Ivanov O, Fernandez K, Farha MJ, Gonzalez V, Wengler C, Bhatnagar A, Neuner GA, Kopkash K, Rahman S, Costa P. A multi-center trial of intra-operative electronic brachytherapy during breast conservation surgery for early stage breast cancer: Early results of unplanned boost participants [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P1-10-20.

Vertebral Tortuosity Index in Patients with Non-Connective Tissue Disorder-Related Aneurysm Disease

OBJECTIVE

The vertebral tortuosity index (VTI) predicts increased risk of acute aortic events in patients with known genetic aortopathies. This study describes the VTI in a cohort of patients with non-connective tissue disorder-related large aneurysms.

METHODS

Hospital imaging records from July 2012 to March 2016 were interrogated to identify patients with aneurysmal disease who had undergone computed tomographic angiography that included imaging of vertebral arteries. A control group of consecutive patients undergoing carotid and vertebral imaging was also assessed. VTI was calculated using the formula: [(centre-line distance) / (straight-line distance)-1] ×100 for all patients, and statistical analysis undertaken to determine whether measured VTI was statistically different in patients of younger age, with larger aneurysms, or an acute presentation. Comparison was made with patients who had no aneurysm disease.

RESULTS

Sixty-five patients were identified with adequate imaging to assess the entire aorta, including vertebral arteries. The majority of patients were male (71%, 46/65) and mean age at the time of the CT scan was 71 years (SD 11.1 years). There were 11 patients under the age of 60 years in this cohort. The mean VTI was 33.17 (SD 20.43). There was no statistically significant difference between different territories of presentation (proximal vs. distal aneurysm, p=.94), age of patient (>60 years vs. <60 years, p=.2), or size of aneurysm (>6 cm vs. <6 cm, p=.09). Acuity of presentation was not predicted by a higher VTI (p=.69). The VTI in patients with aneurysms was higher than in patients without aneurysm disease (VTI = 16.1, p<.005) CONCLUSIONS: An elevated VTI is consistently present in patients with degenerative aneurysms and has potential as a universally available predictive measurement. However, the increased VTI in the older cohort without connective tissue disease may not carry the same predictive value for acute presentations as has been demonstrated in younger patients with a known genetic basis for their aortopathy.

An investigation of Saudi Arabian MR radiographers' knowledge and confidence in relation to MR image-quality-related errors

OBJECTIVE

To investigate MR radiographers' current knowledge base and confidence level in relation to quality-related errors within MR images.

METHOD

Thirty-five MR radiographers within 16 MRI departments in the Kingdom of Saudi Arabia (KSA) independently reviewed a prepared set of 25 MR images, naming the error, specifying the error-correction strategy, scoring how confident they were in recognising this error and suggesting a correction strategy by using a scale of 1-100. The datasets were obtained from MRI departments in the KSA to represent the range of images which depicted excellent, acceptable and poor image quality.

RESULTS

The findings demonstrated a low level of radiographer knowledge in identifying the type of quality errors and when suggesting an appropriate strategy to rectify those errors. The findings show that only (n = 7) 20% of the radiographers could correctly name what the quality errors were in 70% of the dataset, and none of the radiographers correctly specified the error-correction strategy in more than 68% of the MR datasets. The confidence level of radiography participants in their ability to state the type of image quality errors was significantly different (p < 0.001) for who work in different hospital types.

CONCLUSION

The findings of this study suggest there is a need to establish a national association for MR radiographers to monitor training and the development of postgraduate MRI education in Saudi Arabia to improve the current status of the MR radiographers' knowledge and direct high quality service delivery.

Patient-Reported Outcomes after Monitoring, Surgery, or Radiotherapy for Prostate Cancer

BACKGROUND

Robust data on patient-reported outcome measures comparing treatments for clinically localized prostate cancer are lacking. We investigated the effects of active monitoring, radical prostatectomy, and radical radiotherapy with hormones on patient-reported outcomes.

METHODS

We compared patient-reported outcomes among 1643 men in the Prostate Testing for Cancer and Treatment (ProtecT) trial who completed questionnaires before diagnosis, at 6 and 12 months after randomization, and annually thereafter. Patients completed validated measures that assessed urinary, bowel, and sexual function and specific effects on quality of life, anxiety and depression, and general health. Cancer-related quality of life was assessed at 5 years. Complete 6-year data were analyzed according to the intention-to-treat principle.

RESULTS

The rate of questionnaire completion during follow-up was higher than 85% for most measures. Of the three treatments, prostatectomy had the greatest negative effect on sexual function and urinary continence, and although there was some recovery, these outcomes remained worse in the prostatectomy group than in the other groups throughout the trial. The negative effect of radiotherapy on sexual function was greatest at 6 months, but sexual function then recovered somewhat and was stable thereafter; radiotherapy had little effect on urinary continence. Sexual and urinary function declined gradually in the active-monitoring group. Bowel function was worse in the radiotherapy group at 6 months than in the other groups but then recovered somewhat, except for the increasing frequency of bloody stools; bowel function was unchanged in the other groups. Urinary voiding and nocturia were worse in the radiotherapy group at 6 months but then mostly recovered and were similar to the other groups after 12 months. Effects on quality of life mirrored the reported changes in function. No significant differences were observed among the groups in measures of anxiety, depression, or general health-related or cancer-related quality of life.

CONCLUSIONS

In this analysis of patient-reported outcomes after treatment for localized prostate cancer, patterns of severity, recovery, and decline in urinary, bowel, and sexual function and associated quality of life differed among the three groups. (Funded by the U.K. National Institute for Health Research Health Technology Assessment Program; ProtecT Current Controlled Trials number, ISRCTN20141297 ; ClinicalTrials.gov number, NCT02044172 .).

An investigation of the emotion of disgust as an affective barrier to intention to screen for colorectal cancer

Colorectal cancer (CRC) screening participation remains unacceptably low. This study investigated the emotion of disgust as a potential deterrent to intention to screen for CRC. The study utilised a convenience sample of individuals' 40-70 years of age to complete an online survey. Participants included 30 men and 118 women recruited between December 1, 2013 and March 31, 2014. Data on socio-demographics, health status, screening intentions and emotional barriers to bowel screening were collected via an on-line survey. Logistic regression analysis was utilised to investigate predictors of screening intention. Individuals were more likely to report intention to screen if they had prior screening experience, and reported fewer emotional concerns to screening for CRC. Results implicate disgust as a predictor of screening avoidance among participants. Specifically, higher reported faecal disgust was predictive of a 3% decrease in screening intention. This study was the first to empirically position disgust alongside other negative emotional states as an affective barrier to screening for CRC. Trait disgust sensitivity was not a reliable predictor of screening intention. This research suggests that anticipated faecal disgust may contribute to avoidance of screening for CRC.

Preparedness for use of the rapid result HIV self-test by gay men and other men who have sex with men (MSM): a mixed methods exploratory study among MSM and those involved in HIV prevention and care

Objectives

The aim of the study was to explore preparedness for the HIV self‐test among men who have sex with men (MSM) and those involved in HIV prevention and care.

Methods

A mixed methods exploratory research design was employed, detailing awareness and willingness to use the self‐test and the perceived barriers and facilitators to implementation. Quantitative and qualitative data collection and analysis were completed in parallel. Descriptive and inferential analysis of cross‐sectional bar‐based survey data collected from MSM through a self‐completed questionnaire and oral fluid specimen collection (n = 999) was combined with qualitative, thematic, analysis of data collected through 12 expert focus groups (n = 55) consisting of gay men, National Health Service (NHS) staff, community organizations, entrepreneurs and activists. Findings were subsequently combined and assessed for synergies.

Results

Among MSM, self‐test awareness was moderate (55%). Greater awareness was associated with increased educational attainment [adjusted odds ratio 1.51; 95% confidence interval (CI) 1.00–2.30; P = 0.05] and previous history of sexually transmitted infection (STI) testing (adjusted odds ratio 1.63; 95% CI 1.11–2.39; P = 0.01). Willingness to use the test was high (89%) and associated with meeting sexual partners online (unadjusted odds ratio 1.96; 95% CI 1.31–2.94; P < 0.001). Experts highlighted the overall acceptability of self‐testing; it was understood as convenient, discreet, accessible, and with a low burden to services. However, some ambivalence towards self‐testing was reported; it could reduce opportunities to engage with wider services, wider health issues and the determinants of risk.

Conclusions

Self‐testing represents an opportunity to reduce barriers to HIV testing and enhance prevention and access to care. Levels of awareness are moderate but willingness to use is high. Self‐testing may amplify health inequalities.

Calcification of a Synthetic Renovascular Graft in a Child

INTRODUCTION

Vascular grafts, especially in paediatric cases, need to be durable. Common failures such as thrombosis are well documented with research efforts directed towards them. However, there are lesser known causes of graft failure, such as graft calcification, and these also require further research focus.

REPORT

A paediatric case is described in which a synthetic renovascular graft, implanted for mid-aortic syndrome, became calcified, necessitating surgical intervention to resolve graft malfunction. Significant calcification in the limb of a bifurcated polyethylene terephthalate graft was found to be the cause of resistant stenosis and refractory hypertension. Histology conducted on the explanted limb showed the presence of multinuclear giant cells, indicating a chronic foreign body response.

DISCUSSION

Calcification of vascular grafts is probably more common than previously recognised. Stenosis typically resistant to angioplasty may result in the long term and thus leading to surgical intervention. In young children, this is suboptimal as these grafts need to last throughout adulthood. Explanted prosthetic grafts should be sent to specialist registries such as that in Strasbourg to be optimally assessed so that contributory factors can be identified.

Control Release Anesthetics to Enable an Integrated Anesthetic-mesenchymal Stromal Cell Therapeutic

While general anesthetics control pain via consciousness regulation, local anesthetics (LAs) act by decreasing sensation in the localized area of administration by blocking nerve transmission to pain centers. Perioperative intra-articular administration of LAs is a commonly employed practice in orthopedic procedures to minimize patient surgical and post-surgical pain and discomfort. LAs are also co-administered with cellular mesenchymal stromal cell (MSC) therapies for a variety of tissue regenerative and inflammatory applications including osteoarthritis (OA) treatment; however, LAs can affect MSC viability and function. Therefore, finding an improved method to co-administer LAs with cells has become critically important. We have developed a sustained release LA delivery model that could enable the co-administration of LAs and MSCs. Encapsulation of liposomes within an alginate matrix leads to sustained release of bupivacaine as compared to bupivacaine-containing liposomes alone. Furthermore, drug release is maintained for a minimum of 4 days and the alginate-liposome capsules mitigated the adverse effects of bupivacaine on MSC viability.

A Comparison of Accuracy of Image- versus Hardware-based Tracking Technologies in 3D Fusion in Aortic Endografting

OBJECTIVES

Fusion of three-dimensional (3D) computed tomography and intraoperative two-dimensional imaging in endovascular surgery relies on manual rigid co-registration of bony landmarks and tracking of hardware to provide a 3D overlay (hardware-based tracking, HWT). An alternative technique (image-based tracking, IMT) uses image recognition to register and place the fusion mask. We present preliminary experience with an agnostic fusion technology that uses IMT, with the aim of comparing the accuracy of overlay for this technology with HWT.

METHOD

Data were collected prospectively for 12 patients. All devices were deployed using both IMT and HWT fusion assistance concurrently. Postoperative analysis of both systems was performed by three blinded expert observers, from selected time-points during the procedures, using the displacement of fusion rings, the overlay of vascular markings and the true ostia of renal arteries. The Mean overlay error and the deviation from mean error was derived using image analysis software. Comparison of the mean overlay error was made between IMT and HWT. The validity of the point-picking technique was assessed.

RESULTS

IMT was successful in all of the first 12 cases, whereas technical learning curve challenges thwarted HWT in four cases. When independent operators assessed the degree of accuracy of the overlay, the median error for IMT was 3.9 mm (IQR 2.89-6.24, max 9.5) versus 8.64 mm (IQR 6.1-16.8, max 24.5) for HWT (p = .001). Variance per observer was 0.69 mm(2) and 95% limit of agreement ±1.63.

CONCLUSION

In this preliminary study, the error of magnitude of displacement from the "true anatomy" during image overlay in IMT was less than for HWT. This confirms that ongoing manual re-registration, as recommended by the manufacturer, should be performed for HWT systems to maintain accuracy. The error in position of the fusion markers for IMT was consistent, thus may be considered predictable.

Comparison of optimised endovaginal vs external array coil T2-weighted and diffusion-weighted imaging techniques for detecting suspected early stage (IA/IB1) uterine cervical cancer

OBJECTIVE

To compare sensitivity and specificity of endovaginal versus external-array coil T2-W and T2-W + DWI for detecting and staging small cervical tumours.

METHODS

Optimised endovaginal and external array coil MRI at 3.0-T was done prospectively in 48 consecutive patients with stage Ia/Ib1 cervical cancer. Sensitivity/specificity for detecting tumour and parametrial extension against histopathology for a reading radiologist were determined on coronal T2-W and T2W + DW images. An independent radiologist also scored T2-W images without and with addition of DWI for the external-array and endovaginal coils on separate occasions >2 weeks apart. Cohen's kappa assessed inter- and intra-observer agreement.

RESULTS

Median tumour volume in 19/38 cases positive on subsequent histology was 1.75 cm(3). Sensitivity, specificity, PPV, NPV were: reading radiologist 91.3 %, 89.5 %, 91.3 %, 89.5 %, respectively; independent radiologist T2-W 82.6 %, 73.7 %, 79.1 %, 77.8 % for endovaginal, 73.9 %, 89.5 %, 89.5 %, 73.9 % for external-array coil. Adding DWI improved sensitivity and specificity of endovaginal imaging (78.2 %, 89.5 %); adding DWI to external-array imaging improved specificity (94.7 %) but reduced sensitivity (66.7 %). Inter- and intra-observer agreement on T2-W + DWI was good (kappa = 0.67 and 0.62, respectively).

CONCLUSION

Endovaginal coil T2-W MRI is more sensitive than external-array coil for detecting tumours <2 cm(3); adding DWI improves specificity of endovaginal imaging but reduces sensitivity of external-array imaging.

KEY POINTS

• Endovaginal more accurate than external-array T2-W MRI for detecting small cervical cancers. • Addition of DWI improves sensitivity and specificity of endovaginal T2-W imaging. • Addition of DWI substantially reduces sensitivity of external-array T2-W imaging.

Abstract P3-12-11: One-year follow-up results of a multi-center trial of intra-operative radiation therapy using electronic brachytherapy at the time of breast conservation surgery for early stage breast cancer

Objectives: To describe observations of one-year follow-up of subjects treated on a multi-center, non-randomized study with a single fraction of intra-operative radiation therapy (IORT) using the Xoft® Axxent® Electronic Brachytherapy System® (eBx®) immediately following surgical resection of early stage breast cancer.

Methods: Two-hundred forty three (243) subjects were treated at seventeen (17) US hospitals. Upon meeting the inclusion/exclusion criteria, patients underwent partial mastectomy, placement of a balloon applicator suitable to the surgical bed in the lumpectomy cavity and inflated with saline (30 – 75 cc). The skin was temporarily closed over the balloon and ultrasound examination performed to confirm that the balloon surface-to-skin distance was &gt; 1.0 cm. A single fraction of intra-operative radiation therapy was delivered to the lumpectomy cavity using the Xoft System. The prescribed dose was 20 Gy at the balloon applicator surface, and the mean treatment time was 10.2 minutes. After treatment, the balloon was deflated and removed, and skin sutured.

Results: Two-hundred forty two (242) subjects received the prescribed dose of 20 Gy; one subject received 21 Gy. Eighteen (18) subjects were removed from the primary analysis post-IORT due to positive surgical margins (N=2), positive sentinel lymph nodes (N=13), or balloon surface-to-skin distance &lt; 1 cm (N=3). However, these eighteen subjects will continue to be followed for the duration of this 10-year study. The mean follow-up for the two-hundred twenty five evaluable subjects is 494 days (range 300-465 days). The mean patient age was 65 years (41-89). Forty-nine subjects (21.8%) had ductal carcinoma in situ, one-hundred seventy one (76%) had invasive ductal carcinoma, and five (2.2%) had unknown histology. The DCIS nuclear grade was evenly distributed between high (N=18) and low/intermediate (N=23); 5 were unknown. Invasive cancer was Grade 1-2 in 142/171 cases. Two-hundred twelve subjects (94.2%) had T1 lesions, eight (3.6%) had T2 lesions, and five (2.2%) were unknown. The mean tumor size was 10.6 mm ± 6.4 mm. At the time of the last subject visit, 49/318 reported adverse events were Grade 2 or higher, and only 1/100 had serious side effects, i.e. infection. One patient died of aortic aneurism and two developed secondary malignancies, i.e. ovarian cancer and chronic lymphocytic leukemia. The most frequent side effects were seroma (12.5%), erythema (9.1%), and induration (7.5%). Cosmesis was excellent to good in 95% of cases.

Conclusions: IORT using the Xoft System as part of the conservative treatment of breast cancer is safe, with low morbidity. Early results from this multi-center trial demonstrate this short, convenient course of radiation therapy for select patients with early stage breast cancer has excellent-to-good cosmetic results and a low rate of low-grade adverse events.

Citation Format: Syed AMN, Chang H, Schwartzberg BS, Bremner AK, Lopez-Penalver C, Coomer C, Boylan S, Chakravarthy A, Vito CA, Bhatnagar A, Proulx GM, Dooley WC, Davis M, Golder SL, Ivanov O, Fernandez K, Rahman S. One-year follow-up results of a multi-center trial of intra-operative radiation therapy using electronic brachytherapy at the time of breast conservation surgery for early stage breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-12-11.

Energy intake and expenditure of improvised explosive device detection dogs

Improvised explosive device detection (IDD) dogs explore up to 40 km of land daily and therefore have energetic demands that may be above the National Research Council’s requirement for working dogs. This study was designed to quantify metabolic energy intake (MEI) and total energy expenditure (TEE) in a group of IDD dogs. Two groups of dogs that had undergone different training protocols (CP1, n=8 and CP2, n=11) underwent a 5-day deployment simulation that consisted of combined road clearing, orbit and point-to-point activities and lasted approximately 9 h per day. The CP1 dogs were fed according to the IDD Marine Corps Manual, while CP2 dogs were offered additional calories based on pilot study data of energy expenditure. The MEI was calculated based on feed intake rates and chemical composition of the diets. TEE was quantified using the doubly-labelled water technique in 2 of the CP1 dogs and 7 of the CP2 dogs. During the 5-day deployment simulation the MEI ranged from 189-310 kcal/bodyweight (BW)0.75 per day, with the CP2 dogs at the higher end because they were offered more feed. The TEE ranged between 375-507 kcal/BW0.75 per day, above the MEI, suggesting the dogs were in negative energy balance and metabolic reserves within the body were combusted for energy production. These findings reveal that energy requirements of deployed military working dogs are higher than previously published metabolic energy requirements of working dogs.