Surveillance Imaging In Patients Research Articles

MDB-81. THE ROLE OF SURVEILLANCE IMAGING IN DETECTING RECURRENCE OF MEDULLOBLASTOMA

Abstract BACKGROUND In patients with medulloblastoma, imaging with magnetic resonance imaging (MRI) of the brain and spine plays an integral role in surveillance following treatment completion. The primary objective of imaging surveillance is to detect early recurrences, possibly leading to better salvage treatment. However, there is a lack of data to demonstrate the utility of imaging with possible demerits associated with increased resource utilization, scan-related anxiety, and lead or length time bias. METHODS Patients with histopathological confirmation of medulloblastoma treated in our institute between 2005 and 2022 were screened to identify patients with image-detected recurrences and corresponding documentation of symptoms and imaging intent (surveillance or directed by symptoms). RESULTS From a cohort of 545 patients treated during the period, 212 had disease recurrence, of which 153 had known symptomatology during the first recurrence. A total of 114 patients (75%) were having recurrence detected prompted by symptoms. Group 4 medulloblastomas were commonly seen to have recurrence detected on surveillance imaging (35%) compared to the SHH subgroup (25%) and group 3 (12%). During the final analysis, 141 of 153 patients had died. The median survival of patients detected to have asymptomatic relapse was 14 months compared to 5 months for symptomatic recurrences (p=0.03). The overall survival (calculated from index diagnosis) was not statistically significant between the two groups, with a 3-year survival of 53% (asymptomatic) vs 46% (symptomatic) (p=0.51). CONCLUSION In most patients, recurrences were detected by unplanned imaging ahead of scheduled surveillance imaging prompted by symptoms. Although the survival after recurrence is better in patients diagnosed on surveillance imaging, the overall survival was not different between the two groups, suggesting the possibility of lead time bias. Prospective studies are warranted to determine the role and appropriate frequency of surveillance imaging in patients with medulloblastoma.

The Role of Surveillance Imaging in Patients with Advanced Laryngeal Cancer

Background: While almost one-third of patients treated for laryngeal cancer will experience disease recurrence, the current National Comprehensive Cancer Network guidelines do not recommend routine post-treatment imaging follow-up. We aimed to examine the yield of post-treatment imaging surveillance among patients with primary advanced laryngeal cancer. Methods: Patients treated for advanced-stage laryngeal carcinoma between 2000 and 2020 in a tertiary care medical center were retrospectively reviewed. Data collected included demographics, clinical and pathological features, treatment modalities, tumor recurrence data including the diagnostic modality (patient’s symptoms, physical examination, or imaging), and outcome. Results: The cohort included 123 patients with advanced-stage laryngeal cancer. Thirty-five (28.7%) patients experienced disease recurrence with fourteen recurrences (40%) diagnosed by imaging. Patients diagnosed by imaging had a shorter time to recurrence diagnosis (23.8 vs. 45.9 months, p-value = 0.016), with similar 5-year overall and disease-specific survival (20.6% vs. 26.6%, log-rank p-value = 0.53 and 62.1% vs. 59.7%, log-rank p-value = 0.87, respectively). Conclusions: Performance of routine post-treatment imaging follow-up in patients with advanced laryngeal cancer was associated with a shorter time to diagnosis of recurrence and similar survival rates. Imaging follow-up should be considered in cases where clinical follow-up is limited and according to the judgment of the treating physician.

Impact of Surveillance Imaging in Patients with HPV-Associated Oropharyngeal Carcinomas Treated with Definitive Radiation and Chemotherapy

Post-treatment surveillance imaging for HPV-associated oropharyngeal carcinomas (OPCs) differs among physicians and institutions. Surveillance imaging can detect disease progression earlier, but can also contribute to anxiety and cost, without proven disease-free or survival benefit. We sought to determine the number of surveillance scans needed to detect a recurrence in patients with HPV-associated OPCs. We included consecutive patients with locally advanced HPV-associated OPC that received definitive concurrent chemoradiotherapy (CRT) with 70 Gy between March 1, 2017 to July 31, 2019. First post-treatment scans were defined as the first scans following the end of CRT. Surveillance scans were defined as body FDG PET/CTs, neck or chest CTs, and neck MRIs taken after the first post-treatment scans showed no evidence of disease. Any scans ordered to follow suspicious lesions on first post-treatment scans were not counted as surveillance scans. Recurrences were classified as detected by first post-treatment scans, surveillance scans, clinical exam, or incidental findings. The number of surveillance scans needed to detect 1 recurrence was determined by dividing the number of surveillance scans by the number of recurrences detected by surveillance scans. There were a total of 275 patients with median follow-up of 39.8 months (Interquartile Range (IQR), 34.9-47.8). Surveillance scans were first taken at a median of 12.1 months (IQR, 9.2-16) post-CRT. There were 27 (9.8%) patients who had a recurrence: 7 (2.5%) had locoregional recurrence (LR), 19 (6.9%) had distant metastasis (DM), and 1 (0.4%) had both LR and DM. LR was detected at a median of 5.8 months (IQR, 3.4-10.6) post-CRT and DM was detected at a median of 9.5 months (IQR, 4.8-14.3) post-CRT. Of all recurrences, 11/27 (40.7%) were first post-treatment scan detected, 10 (37.0%) were surveillance scan detected, 5 (18.5%) were clinical exam detected, and 1 (3.7%) was incidentally detected on lung cancer screening. Four (50%) LRs were first post-treatment detected (median time to detection, MTD: 4.2 months), 3 (37.5%) were clinical exam detected (MTD: 6.7 months), and 1 (12.5%) was surveillance detected (MTD: 9.0 months). For DM, 9 (45%) were surveillance detected (MTD: 12.7 months), 8 (40%) were first post-treatment detected (MTD: 4.1 months), 2 (10%) were clinical exam detected (MTD: 18.9 months), and 1 (5%) was incidentally detected (MTD: 12.1 months). A total of 702 surveillance scans were taken during the follow-up period. The number of surveillance scans needed to detect 1 LR/DM was 71 overall, 50 within 2 years and 254 beyond 2 years from CRT. First post treatment scans detect most recurrences for HPV-associated OPC. A high burden of surveillance scans is needed to detect one recurrence, especially beyond 2 years from CRT.

SP5.3 The risk of hepatic pseudoaneurysm after liver trauma in relation to the severity of liver injury: A meta-analysis and meta-regression analysis

Abstract Aims To determine the risk of hepatic pseudoaneurysm after liver trauma in relation to the severity of liver injury. Methods We performed a systematic review and meta-analysis in compliance with PRISMA statement standards. A search of electronic information sources was conducted to identify all studies reporting the risk of hepatic pseudoaneurysm after liver trauma. The JBI assessment tool was used to assess the risk of bias of the included studies. Random-effects models were applied to calculate pooled outcome data. Results A total of 2030 patients from six studies were included. Based on the American Association for the Surgery of Trauma classification system, 21% had grade I injury; 33% grade II injury; 28% grade III injury; 12% grade IV injury; 5% grade V injury. The pooled risk of hepatic pseudoaneurysm was 1.8% (95% CI 1.1-2.5%). The risk was 0.4% (0-1.2%) in patients with grade I injury, 0.7% (0-1.7%) in patients with grade II injury; 1.5% (0.4-2.7%) in patients with grade III injury; 4.6% (1.4-7.7%) in patients with grade IV injury; 10.6% (1.8-22.9%) in patients with grade V injury. The average time between liver injury and detection of hepatic pseudoaneurysm was 6 days (1-10). Conclusions The risk of hepatic pseudoaneurysm after liver trauma increases as the severity of liver injury increases. Hepatic pseudoaneurysms are rare after grade I or grade II injuries, and increasingly common after grades III, IV and V injuries. We do not hesitate to recommend routine surveillance imaging in patients with grade III to V injuries.

Automated cross-sectional view selection in CT angiography of aortic dissections with uncertainty awareness and retrospective clinical annotations

Surveillance imaging of patients with chronic aortic diseases, such as aneurysms and dissections, relies on obtaining and comparing cross-sectional diameter measurements along the aorta at predefined aortic landmarks, over time. The orientation of the cross-sectional measuring planes at each landmark is currently defined manually by highly trained operators. Centerline-based approaches are unreliable in patients with chronic aortic dissection, because of the asymmetric flow channels, differences in contrast opacification, and presence of mural thrombus, making centerline computations or measurements difficult to generate and reproduce. In this work, we present three alternative approaches – INS, MCDS, MCDbS – based on convolutional neural networks and uncertainty quantification methods to predict the orientation (ϕ,θ) of such cross-sectional planes. For the monitoring of chronic aortic dissections, we show how a dataset of 162 CTA volumes with overall 3273 imperfect manual annotations routinely collected in a clinic can be efficiently used to accomplish this task, despite the presence of non-negligible interoperator variabilities in terms of mean absolute error (MAE) and 95% limits of agreement (LOA). We show how, despite the large limits of agreement in the training data, the trained model provides faster and more reproducible results than either an expert user or a centerline method. The remaining disagreement lies within the variability produced by three independent expert annotators and matches the current state of the art, providing a similar error, but in a fraction of the time.

WED-271 - Improved survival with regular surveillance imaging in patients with primary sclerosing cholangitis

WED-271 - Improved survival with regular surveillance imaging in patients with primary sclerosing cholangitis

O150 The risk of hepatic pseudoaneurysm after liver trauma in relation to the severity of liver injury: a meta-analysis and meta-regression analysis

Abstract Introduction A systematic review and meta-analysis was conducted to determine the risk of hepatic pseudoaneurysm after liver trauma in relation to the severity of liver injury. Methods We performed a systematic review and meta-analysis in compliance with PRISMA statement standards. A search of electronic information sources was conducted to identify all studies reporting the incidence of hepatic pseudoaneurysm after liver trauma. The JBI assessment tool was used to assess the risk of bias. Random-effects models were applied to calculate pooled outcome data. Results A total of 2030 patients from six studies were included. Based on the American Association for the Surgery of Trauma classification system, 21% had grade I injury; 33% grade II injury; 28% grade III injury; 12% grade IV injury; 5% grade V injury. The pooled risk of hepatic pseudoaneurysm was 1.8% (95% CI 1.1-2.5%). The risk was 0.4% (0-1.2%) in patients with grade I injury, 0.7% (0-1.7%) in patients with grade II injury; 1.5% (0.4-2.7%) in patients with grade III injury; 4.6% (1.4-7.7%) in patients with grade IV injury; 10.6% (1.8-22.9%) in patients with grade V injury. The average time between liver injury and detection of hepatic pseudoaneurysm was 6 days (1-10). Conclusion The risk of hepatic pseudoaneurysm after liver trauma increases as the severity of liver injury increases. Hepatic pseudoaneurysms are rare after grade I or grade II injuries, and increasingly common after grades III, IV and V injuries. We do not hesitate to recommend routine surveillance imaging in patients with grade III to V injuries.

The risk of hepatic pseudoaneurysm after liver trauma in relation to the severity of liver injury: a meta-analysis and meta-regression analysis.

To determine the risk of hepatic pseudoaneurysm after liver trauma in relation to the severity of liver injury. We performed a systematic review and meta-analysis in compliance with PRISMA statement standards (Registration Number: CRD42022328834). A search of electronic information sources was conducted to identify all studies reporting the risk of hepatic pseudoaneurysm after liver trauma. The JBI assessment tool was used to assess the risk of bias of the included studies. Random-effects models were applied to calculate pooled outcome data. A total of 2030 patients from six studies were included. Based on the American Association for the Surgery of Trauma classification system, 21% had grade I injury; 33% grade II injury; 28% grade III injury; 12% grade IV injury and 5% grade V injury. The pooled risk of hepatic pseudoaneurysm was 1.8% (95% CI 1.1-2.5%). The risk was 0.4% (0-1.2%) in patients with grade I injury, 0.7% (0-1.7%) in patients with grade II injury; 1.5% (0.4-2.7%) in patients with grade III injury; 4.6% (1.4-7.7%) in patients with grade IV injury and 10.6% (1.8-22.9%) in patients with grade V injury. The average time between liver injury and detection of hepatic pseudoaneurysm was 6 days(95% CI 1-10) CONCLUSIONS: The risk of hepatic pseudoaneurysm after liver trauma increases as the severity of liver injury increases. Hepatic pseudoaneurysms are rare after grade I or grade II injuries, and increasingly common after grades III, IV and V injuries. We recommend routine surveillance imaging in patients with grade III to V injuries.

Surveillance Imaging with PET/CT and CT and/or MRI for Head and Neck Cancer and Mortality: A Population-based Study.

Background To the knowledge of the authors, no strong evidence supports surveillance imaging in patients with head and neck cancer (HNC). Purpose To investigate the association between surveillance imaging and mortality using a population-based study design with statewide cancer registry data, all-payer claims data, and health care facility data. Materials and Methods The retrospective population-based study identified patients with HNC diagnosed between January 2012 and December 2017. Current Procedural Terminology codes were used to search surveillance imaging procedures. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% CIs for mortality with adjustment for sex, ethnicity, age, health insurance status, cancer site, stage, and treatment. Results The study identified 1004 patients (mean age, 61 years ± 12 [SD]; 753 men), including 902 patients with squamous cell carcinoma (SCC) HNC and 102 patients with non-SCC. The effect of imaging on mortality among patients with SCC was not statistically significant when the entire sample was analyzed (HR, 0.76; 95% CI: 0.57, 1.02; P = .07). However, in stratified analyses by cancer stage, surveillance imaging was associated with lower mortality among patients with SCC for regionalized cancer stage (HR, 0.55; 95% CI: 0.36, 0.83; P = .005) and distant cancer stage (HR, 0.40; 95% CI: 0.19, 0.83; P = .01). Among patients with non-SCC, surveillance imaging was associated with lower mortality versus no surveillance imaging (HR, 0.19; 95% CI: 0.04, 0.94; P = .04). PET/CT was associated with lower mortality for patients with SCC (HR, 0.29; 95% CI: 0.09, 0.94; P = .04), and CT and/or MRI was associated with lower mortality for patients with non-SCC (HR, 0.11; 95% CI: 0.01, 0.94; P = .04). Conclusion Surveillance imaging was associated with lower mortality among patients with head and neck squamous cell carcinoma with regionalized or distant disease. The surveillance imaging protective association was observed up to 2 years after treatment completion. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Branstetter in this issue.

Lifelong Imaging Surveillance is Indicated for Patients with Primary Retroperitoneal Liposarcoma.

Surveillance imaging of patients with retroperitoneal liposarcoma (RP-LPS) after surgical resection is based on a projected risk of locoregional and distant recurrence. The duration of surveillance is not well defined because the natural history of RP-LPS after treatment is poorly understood. This study evaluated the long-term risk of recurrence and disease-specific survival (DSS) for a cohort of patients with at least 10 years of progression-free survival (10yr-PFS) from their primary resection. The prospective University of California, Los Angeles (UCLA) Sarcoma Database identified RP-LPS patients with 10yr-PFS after initial resection. The patients in the 10yr-PFS cohort were subsequently evaluated for recurrence and DSS. The time intervals start at date of initial surgical resection. Cox proportional hazards models were used to determine factors associated with recurrence and DSS. From 1972 to 2010, 76 patients with RP-LPS had at least 10 years of follow-up evaluation. Of these 76 patients, 39 (51%) demonstrated 10yr-PFS. The median follow-up period was 15 years (range 10-33 years). Among the 10yr-PFS patients, 49% (19/39) experienced a recurrence at least 10 years after surgery. Of those who experienced recurrence, 42% (8/19) died of disease. Neither long-term recurrence nor DSS were significantly associated with age, sex, tumor size, LPS subtype, surgical margin, or perioperative treatment with radiation or chemotherapy. Patients who have primary RP-LPS treated with surgical resection ± multimodality therapy face a long-term risk of recurrence and disease-specific death unacknowledged by current surveillance imaging guidelines. Among the patients with 10yr-PFS, 49% experienced a recurrence, and 42% of those died of disease. These findings suggest a need for lifelong surveillance imaging for patients with RP-LPS.

Association between imaging surveillance frequency and outcomes following surgical treatment of early-stage lung cancer.

Recent studies have suggested that more frequent postoperative surveillance imaging via computed tomography following lung cancer resection may not improve outcomes. We sought to validate these findings using a uniquely compiled dataset from the Veterans Health Administration, the largest integrated health-care system in the United States. We performed a retrospective cohort study of veterans with pathologic stage I non-small cell lung cancer receiving surgery (2006-2016). We assessed the relationship between surveillance frequency (chest computed tomography scans within 2 years after surgery) and recurrence-free survival and overall survival. Among 6171 patients, 3047 (49.4%) and 3124 (50.6%) underwent low-frequency (<2 scans per year; every 6-12 months) and high-frequency (≥2 scans per year; every 3-6 months) surveillance, respectively. Factors associated with high-frequency surveillance included being a former smoker (vs current; adjusted odds ratio [aOR] = 1.18, 95% confidence interval [CI] = 1.05 to 1.33), receiving a wedge resection (vs lobectomy; aOR = 1.21, 95% CI = 1.05 to 1.39), and having follow-up with an oncologist (aOR = 1.58, 95% CI = 1.42 to 1.77), whereas African American race was associated with low-frequency surveillance (vs White race; aOR = 0.64, 95% CI = 0.54 to 0.75). With a median (interquartile range) follow-up of 7.3 (3.4-12.5) years, recurrence was detected in 1360 (22.0%) patients. High-frequency surveillance was not associated with longer recurrence-free survival (adjusted hazard ratio = 0.93, 95% CI = 0.83 to 1.04, P = .22) or overall survival (adjusted hazard ratio = 1.04, 95% CI = 0.96 to 1.12, P = .35). We found that high-frequency surveillance does not improve outcomes in surgically treated stage I non-small cell lung cancer. Future lung cancer treatment guidelines should consider less frequent surveillance imaging in patients with stage I disease.

Optimal timing and interval of imaging for metastatic breast cancer.

1106 Background: Breast cancer is a family of diseases with varying disease trajectories based on intrinsic biology of the tumor. The time of progression varies across &amp; within subtypes, and with increasing rates of drug resistance depending on prior therapeutic exposure. There is no strong consensus about optimal surveillance and routine imaging in patients with metastatic breast cancer (mBC), but many oncologists report that monitoring strategies are based on strategies used in clinical trials. Methods: We reviewed 17 prior Phase III studies that led to FDA approval in mBC. We reviewed 8 studies for ER+ mBC, 5 studies for HER2+ mBC, 2 studies for triple negative (TNBC) mBC, and 2 studies for BRCA+ mBC. We calculated rates of progression or death (POD) per month for the first year on therapy using data from survival analysis tables and compared them across the different types and lines of therapy. Results: Risk of progression in mBC varies based on receptor status and line of therapy (Table). There was a significant difference in POD rates between ER+ therapies compared with all other disease types (HER2+, TNBC, BRCA) (p = 0.012). Patients with TNBC or receiving PARP inhibitors or later line HER2 therapies had higher POD rates than those with ER+ breast cancer or receiving first line HER2 therapy (6.9% vs 4.1% per month; p = 0.0004). No significant difference was seen in the monitoring frequency between ER+ and HER2+ disease (p = 0.39). Conclusions: These data suggest that shorter interval imaging should be performed for patients with TNBC or receiving PARP inhibitors or later line HER2 therapies. Surveillance imaging for patients with mBC should be based on disease biology, number of prior regimens, time since initiation of therapy, and regimen efficacy. Current imaging recommendations are not data-based and do not adjust for new agents that have been approved. Oncologists should integrate these into individualized estimates to determine optimum frequency of imaging in clinical practice and research. [Table: see text]

The Impact of Surveillance Imaging Frequency on the Detection of Distant Disease for Patients with Resected Stage III Melanoma

BackgroundIt is not known whether there is a survival benefit associated with more frequent surveillance imaging in patients with resected American Joint Committee on Cancer stage III melanoma.ObjectiveThe aim of this study was to investigate distant disease-free survival (DDFS), melanoma-specific survival (MSS), post distant recurrence MSS (dMSS), and overall survival for patients with resected stage III melanoma undergoing regular computed tomography (CT) or positron emission tomography (PET)/CT surveillance imaging at different intervals.Patients and MethodsA closely followed longitudinal cohort of patients with resected stage IIIA–D disease treated at a tertiary referral center underwent 3- to 4-monthly, 6-monthly, or 12-monthly surveillance imaging between 2000 and 2017. Survival outcomes were estimated using the Kaplan–Meier method, and log-rank tests assessed the significance of survival differences between imaging frequency groups.ResultsOf 473 patients (IIIA, 19%; IIIB, 31%; IIIC, 49%; IIID, 1%) 30% underwent 3- to 4-monthly imaging, 10% underwent 6-monthly imaging, and 60% underwent 12-monthly imaging. After a median follow-up of 6.2 years, distant recurrence was recorded in 252 patients (53%), with 40% detected by surveillance CT or PET/CT, 43% detected clinically, and 17% with another imaging modality. Median DDFS was 5.1 years (95% confidence interval 3.9–6.6). Among 139 IIIC patients who developed distant disease, the median dMSS was 4.4 months shorter in those who underwent 3- to 4-monthly imaging than those who underwent 12-monthly imaging.ConclusionSelecting patients at higher risk of distant recurrence for more frequent surveillance imaging yields a higher proportion of imaging-detected distant recurrences but is not associated with improved survival. A randomized comparison of low versus high frequency imaging is needed.

18F-FDG PET/CT for Posttreatment Surveillance Imaging of Patients with Stage III Merkel Cell Carcinoma

The purpose of this study was to investigate the diagnostic and prognostic value of 18F-FDG PET/CT for surveillance imaging in patients treated for stage III Merkel cell carcinoma (MCC). Methods: This retrospective study included 61 consecutive stage III MCC patients who were clinically asymptomatic and underwent surveillance 18F-FDG PET/CT. Findings were correlated with either pathology or clinical/imaging follow-up. The median follow-up period was 4.8 y. Statistical analyses were performed. Results:18F-FDG PET/CT detected unsuspected recurrences in 33% patients (20/61) with lesion-based sensitivity, specificity, and accuracy of 92%, 93%, and 93%, respectively. The mean ± SD SUV for malignant and benign lesions was 7.5 ± 3.9 and 3.8 ± 2.0, respectively. Unknown distant metastases, as first recurrence site, were noted in 12 of 61 patients. Those with positive disease on 18F-FDG PET/CT within 1 y of definitive treatment had relatively worse overall survival (P < 0.0001). After adjustment on stage, risk of death increased with a higher SUVmax (hazard ratio for 1 unit = 1.17; P = 0.006) and with a higher number of positive lesions on 18F-FDG PET/CT (hazard ratio for 1 additional lesion = 1.60; P < 0.001). Conclusion: Postdefinitive treatment surveillance 18F-FDG PET/CT scanning detects unsuspected recurrences and has prognostic value. Inclusion of 18F-FDG PET/CT within the first 6 mo after definitive treatment would be appropriate for surveillance and early detection of recurrence. Our data merit further studies to evaluate the prognostic implications.

Impact of double reading on NI-RADS diagnostic accuracy in reporting oral squamous cell carcinoma surveillance imaging - a single-center study.

The Neck Imaging Reporting and Data System (NI-RADS) is an increasingly utilized risk stratification tool for imaging surveillance after treatment for head and neck cancer. This study aims to measure the impact of supervision by subspecialized radiologists on diagnostic accuracy of NI-RADS when initial reading is performed by residents. 150 CT and MRI datasets were initially read by two trained residents, and then supervised by two subspecialized radiologists. Recurrence rates by NI-RADS category were calculated, and receiver operating characteristic (ROC) curves were plotted. After dichotomization of the NI-RADS system (category 1 vs categories 2 + 3+4 and categories 1 + 2 vs 3 + 4), sensitivity, specificity, positive and negative predictive value were calculated. 26% of the reports were modified by the supervising radiologists. Area under the curve of ROC plots values of the supervision session were higher than those of the initial reading session for both the primary site (0.89 vs 0.86) and the neck (0.94 vs 0.91), but the difference was not statistically significant. For dichotomized NI-RADS category assignments, differences between the initial reading and the supervision session were statistically significant regarding specificity and PPV for the primary site (1 + 2 vs 3 + 4 and 1 vs 2 + 3+4) or even for both sites combined (1 vs 2 + 3+4). NI-RADS enables trained resident radiologists to report surveillance imaging in patients with treated oral squamous cell carcinoma with high discriminatory power. Additional supervision by a subspecialized head and neck radiologist particularly improves specificity of radiological reports.

Surveillance imaging during first remission in follicular lymphoma does not impact overall survival.

Although many patients with follicular lymphoma (FL) undergo routine radiographic surveillance during their first remission, no consensus exists on the modality, duration, frequency, or need for routine imaging studies. The authors retrospectively examined the effect of surveillance imaging on relapse detection and overall survival (OS) in patients with FL. Patients with newly diagnosed FL who had a response to induction therapy were identified from the Lymphoid Malignancies Enterprise Architecture Database (LEAD) at Emory University and from the Molecular Epidemiology Resource (MER) of the University of Iowa/Mayo Clinic. Patients were evaluated for both relapse and method of relapse detection (ie, clinical concerns vs radiologic detection through surveillance imaging in an asymptomatic patient). Of 148 patients in the LEAD cohort, 55 (37%) relapsed, and the majority (n = 35; 64%) of relapses were detected clinically. In the MER cohort, 63 of 177 relapses (54%) were detected clinically. There was no significant difference in OS from the date of diagnosis between the 2 methods of relapse detection in the LEAD (hazard ratio [HR], 0.61; 95% CI, 0.13-2.94; P = .54) and MER (HR, 1.02; 95% CI, 0.47-2.21; P = .96) cohorts. Similarly, there was no significant difference in OS from the date of relapse between the 2 methods of relapse detection in the LEAD (HR, 0.47; 95% CI, 0.10-2.27; P = .35) and MER (HR, 1.02; 95% CI, 0.47-2.21; P = .96) cohorts. These findings suggest a limited role for routine surveillance imaging in patients with FL who complete front-line therapy. Future studies should evaluate which patients may benefit from a more aggressive surveillance approach and should explore novel methods of relapse detection.

Recurrence and disease-specific survival after 10-year disease-free interval in patients with primary retroperitoneal liposarcoma: Implications for long-term surveillance.

11546 Background: Surveillance imaging of patients with retroperitoneal liposarcoma (RP-LPS) following surgical resection is based on a projected risk of locoregional and distant recurrence. The duration of surveillance is not well defined as the long-term natural history of RP-LPS after treatment is poorly understood. We evaluate a cohort of RP-LPS patients—without evidence of disease 10 years following initial resection—to assess the long-term risk of recurrence and disease-specific survival (DSS). Methods: The prospectively maintained UCLA Sarcoma Database was used to identify RP-LPS patients who demonstrated 10-year progression-free survival (10yr-PFS) after initial diagnosis and treatment. Patients in the 10yr-PFS cohort were subsequently evaluated for recurrence and DSS. Time intervals start at date of initial surgical resection. Cox proportional hazards models were used to determine factors associated with recurrence and DSS. Results: From 1972-2010, 76 patients with RP-LPS had at least 10 years of follow-up. Of these, 37 (49%) demonstrated 10yr-PFS. Median follow-up was 15 years (range 10-35 years). Among the 10yr-PFS patients, 43% (16/37) developed a recurrence &gt;10 years after the initial surgery, and 19% (7/37) died of disease. Neither long-term recurrence nor DSS were significantly associated with age, sex, tumor size, LPS subtype, surgical margin, or peri-operative treatment with radiation or chemotherapy (Table). Conclusions: Patients with primary RP-LPS treated with surgical resection +/- multimodality therapy have a long-term risk of recurrence and disease-specific death that is unacknowledged by current surveillance imaging guidelines. Among the patients with a 10yr-PFS, 43% developed a recurrence and 19% died of disease. These findings suggest a need for lifelong surveillance imaging in patients with RP-LPS.[Table: see text]

Costs Associated With Imaging Surveillance After Treatment for Head and Neck Cancer

The National Comprehensive Cancer Network recommends imaging within 6 months after treatment for head and neck cancer (HNC). Further imaging is recommended only if the patient has symptoms or abnormal findings on physical examination. However, in many instances, asymptomatic patients continue to have imaging evaluations. To assess practice patterns in surveillance imaging in patients with HNC and evaluate the costs associated with these imaging practices. This single-institution retrospective economic evaluation study screened 435 patients to identify patients newly diagnosed with head and neck mucosal and salivary gland malignant tumors between January 1, 2010, and December 31, 2016. Data analyses were performed from October 25, 2018, to November 24, 2020. Imaging practice patterns. Number and costs of imaging studies during the surveillance period for all patients, patients who remained disease free, and patients who developed recurrence. A total of 136 patients (mean [SD] age at diagnosis, 62 [14] years; 84 [61.8%] male; 106 [77.9%] White) with HNC were included in the study. The oropharynx was the most common subsite (64 [47.1%]), most HNCs were stage IVA (62 [45.6%]), and most patients received definitive radiation-based treatment (71 [52.2%]). During the median surveillance period of 3.2 years (range, 0.3-6.8 years), a mean (SD) of 14 (10) imaging studies were performed for all patients, with a mean (SD) total cost of $36 800 ($24 500). In patients who remained disease free, a mean (SD) of 13 (10) imaging studies were performed during the surveillance period, with a mean (SD) total cost of $35 000 ($21 700). Patients who lacked symptoms had a mean (SD) of 4 (3) studies performed per year, resulting in a mean cost of $9600 ($5900) per year. Patients who developed recurrence had more studies per year of follow-up (mean difference, 5.0; 95% CI, 3.4-6.6) and higher associated mean costs (mean difference, $10 600; 95% CI, $6100-$15 000) than patients who remained disease free. In this economic evaluation study, many patients treated for HNCs received imaging studies beyond what is recommended by National Comprehensive Cancer Network guidelines. These findings suggest that the cost burden of imaging in the asymptomatic patient needs to be considered against the value obtained from routine imaging in this current health care environment.

Inadequate Adherence to Imaging Surveillance and Medical Management in Patients with Duplex Ultrasound-Detected Carotid Artery Stenosis

It is recommended that patients with ≥50% carotid artery stenosis undergo surveillance imaging and atherosclerotic risk reduction medical therapies, regardless of whether revascularization is performed. The objective of this study was to determine rates of adherence to these recommended measures and to identify risk factors for nonadherence. A retrospective analysis was performed of all carotid duplex ultrasound (DUS) from 2016 to 2017 at a single institution. Patients with unilateral or bilateral ≥50% carotid stenosis were included. Primary outcomes were rates and timing of surveillance imaging and medication regimen. Patient and study characteristics were compared using univariate and multivariable analyses. A subgroup analysis of patients with a new finding of carotid stenosis was also performed. Carotid stenosis >50% was detected in 340 patients. Overall, 182 patients (54%) had follow-up imaging (median 261 days [IQR 166-366]) and 158 patients (46%) had no imaging follow-up (NIFU). NIFU patients had similar rates of aspirin use (86% vs. 88%, P = 0.6) and tobacco cessation counseling (71% vs. 71%, P = 0.8) but had less statin use (85% vs. 94%, P = 0.01) compared to those with imaging follow-up. Subsequent carotid revascularization was more common in patients with imaging follow-up (18% vs. 3%, P < 0.001). NIFU patients were less likely to have Medicare or commercial insurance (54% vs. 75%, P < 0.001). The indication for DUS in NIFU patients, compared to those in follow up, was less commonly neurologic symptoms (11% vs. 14%), more commonly other clinical findings (35% vs. 16%), and more commonly as work up before nonvascular surgery (25% vs. 4%, P < 0.001), respectively. NIFU rates decreased with increasing degree of carotid stenosis. Prior carotid intervention, prior DUS, or DUS ordered by a vascular surgeon were characteristics associated with imaging follow-up (P < 0.05 for all). In a subgroup of 160 patients with new carotid stenosis, a majority (64%) had NIFU and statin use was lower in these patients (82% vs. 96%, P = 0.007). On multivariable analysis, preop indication was predictive of NIFU (odds ratio [OR] 8.1 [95% confidence interval, CI 2.5-26.4], P < 0.001) whereas protective factors included: 70-80% stenosis (OR 0.33 [95% CI 0.14-0.76], P = 0.01), study ordered by vascular surgeon (OR 0.40 [95% CI 0.19-0.83], P = 0.01), and Medicare/commercial insurance (OR 0.36 [95% CI 0.2-0.66], P = 0.001). Nearly half of patients found to have ≥50% carotid stenosis on DUS had no imaging follow-up; these patients were less likely to be on recommended statin therapy. The benefits of nonrevascularization-based treatments for carotid disease require adherence to therapy. Forgoing surveillance imaging in patients with hemodynamically significant carotid stenosis should be a shared decision between provider and patient and does not obviate the need for medical therapies.

Benign skull and subdural lesions in patients with prior medulloblastoma therapy.

To report on our institutional cohort of patients and review the literature of medulloblastoma patients who developed skull/subdural-based lesions following treatment. Following institutional review board (IRB) approval, we retrospectively reviewed the medical records of four children with a history of treated medulloblastoma who developed non-specific skull-based/subdural lesions incidentally found on surveillance imaging. Biopsies of the lesions proved the pathology to be low grade and included inflammatory myofibroblastic tumor, cortical fibrous defect consistent with fibroma, fibrous tissue, and fibrous dysplasia. The finding of calvarial or subdural fibrous lesions in children following therapy for medulloblastoma was noted in four out of 201 (136 with available follow-up data) medulloblastoma patients seen or discussed in our institution over the past 10years. These lesions can grow over time and pose a differential diagnostic challenge with metastatic disease when identified. The skull and subdural space should be scrutinized for secondary lesions on surveillance imaging of patients with medulloblastoma who have received craniospinal irradiation as knowledge of this benign occurrence will assist with management.