Major Complications and Adverse Events Related to Use of SpaceOAR Hydrogel for Prostate Cancer Radiotherapy.

OBJECTIVE: To determine the prevalence and severity of SpaceOAR-related adverse events using the Manufacturer and User Facility Device Experience (MAUDE) database. METHODS: We analyzed SpaceOAR-related adverse event reports in the Manufacturer and User Facility Device Experience (MAUDE) database from January 2015 to May 2023. For each report, the event type, associated device and patient problems, event description, event timing, and event severity stratified by the Common Terminology Criteria for Adverse Events version 5.0 (CTCAE) grading system were recorded. RESULTS: From 2015 to 2022, 206,619 SpaceOAR devices were sold. From January 2015 to May 2023, we identified 981 reports describing 990 SpaceOAR-related adverse events. Malfunctions were the most common event type (N = 626), followed by patient injuries (N = 350) with few reported deaths (N = 5). Device positioning problems were the most frequent device issue (N = 686). Pain was the most reported patient problem (N = 216). Abscesses and fistulas related to the device were each reported in 91 events. A noteworthy portion of relevant adverse events occurred before the initiation of radiation (N = 35, 22.4%), suggesting the device, rather than the radiation, was responsible. In total, 470 (50.2%) and 344 (36.7%) of the adverse events were CTCAE grade 1 and 2, respectively. There were 123 (13.1%) events that were CTCAE grade ≥3. CONCLUSION: We identified multiple reports of SpaceOAR-related adverse events, many of which are more serious than have been reported in clinical trials. While SpaceOAR use is common, suggesting these events are rare, these data highlight the need for continued postmarket surveillance.

Synthetic CT Generation of the Pelvis in Patients With Cervical Cancer: A Single Input Approach Using Generative Adversarial Network.

Multi-modality imaging constitutes a foundation of precision medicine, especially in oncology where reliable and rapid imaging techniques are needed in order to insure adequate diagnosis and treatment. In cervical cancer, precision oncology requires the acquisition of 18F-labeled 2-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET), magnetic resonance (MR), and computed tomography (CT) images. Thereafter, images are co-registered to derive electron density attributes required for FDG-PET attenuation correction and radiation therapy planning. Nevertheless, this traditional approach is subject to MR-CT registration defects, expands treatment expenses, and increases the patient's radiation exposure. To overcome these disadvantages, we propose a new framework for cross-modality image synthesis which we apply on MR-CT image translation for cervical cancer diagnosis and treatment. The framework is based on a conditional generative adversarial network (cGAN) and illustrates a novel tactic that addresses, simplistically but efficiently, the paradigm of vanishing gradient vs. feature extraction in deep learning. Its contributions are summarized as follows: 1) The approach -termed sU-cGAN-uses, for the first time, a shallow U-Net (sU-Net) with an encoder/decoder depth of 2 as generator; 2) sU-cGAN's input is the same MR sequence that is used for radiological diagnosis, i.e. T2-weighted, Turbo Spin Echo Single Shot (TSE-SSH) MR images; 3) Despite limited training data and a single input channel approach, sU-cGAN outperforms other state of the art deep learning methods and enables accurate synthetic CT (sCT) generation. In conclusion, the suggested framework should be studied further in the clinical settings. Moreover, the sU-Net model is worth exploring in other computer vision tasks.

Comparison of multiparametric MRI-based and transrectal ultrasound-based preplans with intraoperative ultrasound-based planning for low dose rate interstitial prostate seed implantation.

PURPOSE: Transrectal ultrasound images are routinely acquired for low dose rate (LDR) prostate brachytherapy dosimetric preplanning (pTRUS), although diagnostic multiparametric magnetic resonance imaging (mpMRI) may serve this purpose as well. We compared the predictive abilities of TRUS vs MRI relative to intraoperative TRUS (iTRUS) to assess the role of mpMRI in brachytherapy preplanning. MATERIALS AND METHODS: Retrospective analysis was performed on 32 patients who underwent iTRUS-guided prostate LDR brachytherapy as either mono- or combination therapy. 56.3% had pTRUS-only volume studies and 43.7% had both 3T-mpMRI and pTRUS preplanning. MRI was used for preplanning and its image fusion with iTRUS was also used for intraoperative guidance of seed placement. Differences in gland volume, seed number, and activity and procedure time were examined, as well as the identification of lesions suspicious for tumor foci. Pearson correlation coefficient and Fisher's Z test were used to estimate associations between continuous measures. RESULTS: There was good correlation of planning volumes between iTRUS and either pTRUS or MRI (r = 0.89, r = 0.77), not impacted by the addition of hormonal therapy (P = 0.65, P = 0.33). Both consistently predicted intraoperative seed number (r = 0.87, r = 0.86). MRI/TRUS fusion did not significantly increase surgical or anesthesia time (P = 0.10, P = 0.46). mpMRI revealed suspicious focal lesions in 11 of 14 cases not visible on pTRUS, that when correlated with histopathology, were incorporated into the plan. CONCLUSIONS: Relative to pTRUS, MRI yielded reliable preplanning measures, supporting the role of MRI-only LDR treatment planning. mpMRI carries numerous diagnostic, staging and preplanning advantages that facilitate better patient selection and delivery of novel dose escalation and targeted therapy, with no additional surgical or anesthesia time. Prospective studies assessing its impact on treatment planning and delivery can serve to establish mpMRI as the standard of care in LDR prostate brachytherapy planning.

Advances in Radiotherapy for Prostate Cancer Treatment.

Major categories of radiotherapy (RT) for prostate cancer (CaP) treatment are: (1) external beam RT (EBRT), and (2) brachytherapy (BT). EBRT are performed using different techniques like three-dimensional conformal RT (3D-CRT), intensity modulated RT (IMRT), volumetric modulated arc therapy (VMAT), and stereotactic body radiation therapy (SBRT), stereotactic radiosurgery (SRS) and intensity modulated proton therapy (IMPT), etc., using a variety of radiation delivery machines, such as a linear accelerator (Linac), Cyberknife robotic system, Gamma knife, Tomotherapy and proton beam machine. The primary advantage of proton beam therapy is sparing of normal tissues and organ at risks (OARs) with comparable coverage of the tumor volume. MR-Linac is the latest addition in the image-guided RT. Robot-assisted brachytherapy is one of the latest technological innovations in the field. With the advancement of technology, radiation therapy for prostate cancer can be improved using high quality multimodal imaging, robot-assistance for brachytherapy as well as EBRT. This chapter presents the advances in radiation therapy for the treatment of prostate cancer.

Influence of radiation treatment technique on outcome and toxicity in anal cancer.

OBJECTIVE: Intensity-modulated radiation therapy (IMRT) has largely supplanted three-dimensional conformal radiation (3D-CRT) for definitive anal cancer treatment due to decreased toxicity and potentially improved outcomes. Convincing data demonstrating its advantages, however, remain limited. We compared outcomes and toxicity with concurrent chemotherapy and IMRT vs 3D-CRT for anal cancer. METHODS: We performed a single-institution retrospective review of patients treated with IMRT or 3D-CRT as part of definitive mitomycin-C/5-fluorouricil-based chemoradiation for anal cancer from January 2003 to December 2012. RESULTS: One hundred sixty-five patients were included, with 61 and 104 receiving IMRT and 3D-CRT, respectively. Overall, 92.7% had squamous cell carcinoma. The mean initial pelvic dose was 48.3 and 44 Gy for IMRT and 3D-CRT, respectively. Complete response, partial response, and disease progression rates were similar (IMRT 83.6, 8.2, 8.2%; 3D-CRT 85.6, 6.7, 7.7%; p = 0.608, p = 0.728, p = 0.729). There was no significant difference in overall survival (p = 0.971), event-free survival (p = 0.900), or local or distant recurrence rates (p = 0.118, p = 0.373). IMRT caused significantly less acute grade 1-2 incontinence (p = 0.035), grade 3-4 pain (p = 0.033), and fatigue (p = 0.030). IMRT patients had significantly fewer chronic post-treatment toxicities (p = 0.008), outperforming 3D-CRT in six of eight toxicities reviewed. Though total treatment length was comparable (43.6 and 44.5 days), IMRT recipients had fewer (27.9 vs 41.3% of patients, p = 0.89), shorter treatment breaks (mean 2.9 vs 4.1 days, p = 0.229). CONCLUSION: This report represents the largest series directly comparing concurrent chemotherapy with IMRT vs 3D-CRT for definitive treatment of anal cancer. IMRT significantly reduced acute and post-treatment toxicities and allowed for safe and effective pelvic dose escalation.

Patterns of cancer recurrence in localized resected hepatocellular carcinoma.

BACKGROUND: Tumor resection in non-metastatic hepatocellular carcinoma (HCC) patients with adequate liver reserve offers a potential cure, but has a high 5-year recurrence rate. We analyzed the patterns of cancer relapse after partial hepatectomy to guide post-operative management. METHODS: A total of 144 HCC patients (1996-2011) after partial hepatectomy were reviewed. Statistical correlations were determined using univariate and partition analyses. RESULTS: A median follow-up of 20 months showed recurrence in 71 (49%) patients, and the median time to recurrence was 11.9 months. Vascular invasion (P<0.01) and number of lesions (P<0.01) predicted for recurrence. Histologic grade was not correlated with recurrence. Twenty-two (31%) patients developed both surgical margin (SM) and concurrent intrahepatic recurrences, and 28 (40%) had non-SM intrahepatic recurrences with no other signs of recurrence. On partition analysis, the risk of marginal recurrence in patients with SM <1 mm and SM ≥1 mm was 35% and 13.5% respectively. Approximately 57% of patients with intrahepatic recurrence had recurrence ≤2.5 cm from SM. CONCLUSIONS: Intrahepatic recurrence after partial hepatectomy is common and is significantly associated with vascular invasion and tumor stage. About 57% of patients with intrahepatic relapse had a recurrence close (≤2.5 cm) to the SM. Additionally, patients with SM <1 mm have a higher recurrence rate and may benefit from adjuvant local therapy.

Surgical duration of cochlear implantation in an academic university-based practice.

OBJECTIVE: Establish the time to safely and efficiently perform cochlear implantation (CI) in a university-based academic center. STUDY DESIGN: Case series with chart review. SETTING: Academic neurotologic referral center. PATIENTS: 424 patients who underwent CI surgery between 2002 and 2010. INTERVENTION: Unilateral, bilateral or revision CI using commercially available devices approved for use in the United States. MAIN OUTCOME MEASURES: mean surgical duration (SD) and mean total operative room time (TORT). RESULTS: Overall mean SD for all 424 patients was 83 ± 30 min (min) whereas the mean TORT was 135 ± 56 min. The mean SD for unilateral CI was 84 ± 18 min for the first implant and 82 ± 22 min for the second implant (p=0.55). The SD for primary and revision CI was 83 ± 18 min and 85 ± 36 min, respectively (p=0.51). The mean SD for pediatric and adult CI was 83 ± 21 min and 83 ± 18 min, respectively (p=0.92). The mean SD without resident assistance was 74 ± 14 min whereas with the assistance of a resident the mean SD was 84 ± 20 min (p=0.02). When ossification was encountered the mean SD was 90 ± 32 min compared to 82 ± 19 min when absent (p<0.001). An association was found between TORT or SD, and the year of surgery, presence of ossification and the involvement of an assistant. CONCLUSION: In a university-based academic center, CI surgery can be safely and efficiently performed, supporting future cost-effectiveness analysis of its current practice.