Post-treatment Surveillance Research Articles

Liquid biopsy posttreatment surveillance in endemic nasopharyngeal carcinoma: a cost-effective strategy to integrate circulating cell-free Epstein-Barr virus DNA

BackgroundThe optimal posttreatment surveillance strategy for nasopharyngeal carcinoma (NPC) remains unclear. Circulating cell-free Epstein-Barr virus (cfEBV) DNA has been recognized as a promising biomarker to facilitate early detection of NPC recurrence. Therefore, we aim to determine whether integrating circulating cfEBV DNA into NPC follow-up is cost-effective.MethodsFor each stage of asymptomatic nonmetastatic NPC patients after complete remission to primary NPC treatment, we developed a Markov model to compare the cost-effectiveness of the following surveillance strategies: routine follow-up strategy, i.e., (1) routine clinical physical examination; routine imaging strategies, including (2) routine magnetic resonance imaging plus computed tomography plus bone scintigraphy (MRI + CT + BS); and (3) routine 18F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT); cfEBV DNA-guided imaging strategies, including (4) cfEBV DNA-guided MRI + CT + BS and (5) cfEBV DNA-guided PET/CT. Clinical probabilities, utilities, and costs were derived from published studies or databases. Sensitivity analyses were performed.ResultsFor all disease stages, cfEBV DNA-guided imaging strategies demonstrated similar survival benefits but were considerably more economical than routine imaging strategies. They only required approximately one quarter of the number of imaging studies compared with routine imaging strategies to detect one recurrence. Specifically, cfEBV DNA-guided MRI + CT + BS was most cost-effective for stage II (incremental cost-effectiveness ratio [ICER] $57,308/quality-adjusted life-year [QALY]) and stage III ($46,860/QALY) patients, while cfEBV DNA-guided PET/CT was most cost-effective for stage IV patients ($62,269/QALY). However, routine follow-up was adequate for stage I patients due to their low recurrence risk.ConclusionsThe cfEBV DNA-guided imaging strategies are effective and cost-effective follow-up methods in NPC. These liquid biopsy-based strategies offer evidence-based, stage-specific surveillance modalities for clinicians and reduce disease burden for patients.

Prostate-Specific Membrane Antigen (PSMA) PET: A Counterpart to Prostate MRI

Abstract Prostate cancer is projected to remain the second leading cause of cancer-related death in men in the United States in 2021[1]. Traditionally, initial staging and post-treatment surveillance require a variety of imaging exams, from bone scan and CT to MRI, however conventional imaging is limited by low sensitivity[2-4]. This has given rise to the development of radiotracers which target molecular processes more specific for prostate cancer, such as 11 C- or 18 F-choline and 18 F-fluciclovine [4] . In December 2020, 68 Ga-prostate-specific membrane antigen-11 (68 Ga-PSMA-11) received FDA approval for use in men with prostate cancer in the United States[5]. Studies have consistently demonstrated superior performance of 68 Ga-PSMA-11, 11 C-/ 18 F-choline and 18 F-fluciclovine PET for cancer detection compared to conventional imaging, particularly at PSA levels of less than 1.0 ng/mL[3, 6-10]. A recent study showed that 68 Ga-PSMA-11 PET led to significantly more frequent changes in patient management than conventional imaging[9]. The increasing availability of PSMA PET/MR scanners is likely to pave the way for simultaneous integration of anatomic, functional and biologic information for men undergoing prostate cancer care[4]. In this article, we provide an overview of the clinical applications of 68 Ga-PSMA-11 PET-MR with case examples.

Potential Clinical Utility of a Targeted Circulating Tumor DNA Assay in Esophageal Adenocarcinoma.

Objective:To explore the clinical utility of circulating tumor DNA (ctDNA) in esophageal adenocarcinoma (EAC) by developing a cost-effective and rapid technique utilising targeted amplicon sequencing.Summary of background data:Emerging evidence suggests that levels of ctDNA in the blood can be used to monitor treatment response and in the detection of disease recurrence in various cancer types. Current staging modalities for EAC such as computerised tomography of the chest/abdomen/pelvis (CT) and positron emission tomography (PET) do not reliably detect occult micro-metastatic disease, the presence of which signifies a poor prognosis. After curative-intent treatment, some patients are still at high risk of recurrent disease, and there is no widely accepted optimal surveillance tool for patients with EAC.Methods:Sixty-two patients with EAC were investigated for the presence of ctDNA using a tumor-informed approach. We designed a custom targeted amplicon sequencing panel of target specific primers covering mutational foci in 9 of the most commonly mutated genes in EAC. Serial blood samples were taken before and after neoadjuvant treatment (NAT), and during surveillance.Results:Somatic mutations were detected in pre-treatment biopsy samples of 55 out of 62 (89%) EAC patients. Mutations in TP53 (80%) were the most common. Out of these 55 patients, 20 (36%) had detectable ctDNA at baseline. The majority (90%) of patients with detectable ctDNA had either locally advanced tumors, nodal involvement or metastatic disease. In patients with locally advanced tumors, disease free survival (DFS) was more accurately stratified using pre-treatment ctDNA status [HR 4.34 (95% CI 0.93–20.21); P = 0.05] compared to nodal status on PET-CT. In an exploratory subgroup analysis, patients who are node negative but ctDNA positive have inferior DFS [HR 11.71 (95% CI 1.16-118.80) P = 0.04]. In blood samples taken before and following NAT, clearance of ctDNA after NAT was associated with a favourable response to treatment. Furthermore, patients who are ctDNA positive during post-treatment surveillance are at high risk of relapse.Conclusions:Our study shows that ctDNA has potential to provide additional prognostication over conventional staging investigation such as CT and PET. It may also have clinical utility in the assessment of response to NAT and as a biomarker for the surveillance of recurrent disease.

Residual meta‐iodobenzyl guanidine (MIBG) positivity following therapy for metastatic neuroblastoma: Patient characteristics, imaging, and outcome

Meta-iodobenzylguanidine(MIBG) scans are used to detect neuroblastoma metastatic lesions at diagnosis and during posttreatment surveillance. MIBG positivity following induction chemotherapy correlates with poor outcome; however, there are reports of patients with progression-free survival despite MIBG positivity at the end of therapy. The factors distinguishing these survivors from patients who progress or relapse are unclear. FDG-positron-emission tomography (PET) scans can also detect metastatic lesions at diagnosis; however, their role in posttherapy surveillance is less well studied. We performed a retrospective analysis of International Neuroblastoma Staging System (INSS) stage 4 patients to identify those with residual MIBG-avid metastatic lesions on end-of-therapy scans without prior progression. Data collected included age, disease sites, histopathology, biomarkers, treatment, imaging studies, and response. Eleven of 265 patients met inclusion criteria. At diagnosis three of 11 patients were classified as intermediate and eight of 11 high risk; nine of 11 had documented marrow involvement. Histologic classification was favorable for four of 10 and MYCN amplification was detected in zero of 11 cases. The median time with persistent MIBG positivity following treatment was 1.5years. Seven patients had at least one PET scan with low or background activity. Biopsies of three of three MIBG-avid residual lesions showed differentiation. All patients remain alive with no disease progression at a median of 4.0years since end of therapy. Persistently MIBG-avid metastatic lesions in subsets of patients following completion of therapy may not represent active disease that will progress. Further studies are needed to determine whether MYCN status or other biomarkers, and/or PET scans, may help identify patients with residual inactive MIBG lesions who require no further therapy.

Patient perspectives on surveillance after head and neck cancer treatment: A systematic review

Current guidelines advise post-treatment surveillance of head and neck cancer (HNC) patients should involve scheduled appointments with a variety of practitioners. Increasing numbers of HNC survivors raise the burden to provide efficient and effective care. With resource limitation, there is growing importance to identify how surveillance can be justified and optimised for survivors. This systematic review presents current evidence on patient perspectives of post-treatment HNC surveillance, aiming to inform future work putting patient priorities at the forefront of surveillance planning. MEDLINE, Embase, the Cochrane Library, NIHR Dissemination Centre, The Kings Fund Library, Clinical Evidence, NHS Evidence and NICE Clinical Evidence were searched to identify publications regarding patient perspectives of HNC post-treatment surveillance. Studies not reporting on both surveillance and patient perspectives were excluded. Three thousand five hundred fifty-eight citations were screened and 49 full-text articles reviewed. Sixteen studies were included in the final review. Three authors reviewed all articles prior to final analysis to ensure all met inclusion criteria. Most evidence was low quality. Study models returned included cross-sectional surveys, structured interviews and one systematic review. Overall, positive perceptions of HNC surveillance were mostly related to increased reassurance. Negative perceptions predominantly focused on anxiety and fear of recurrence, but a lack of psychological support and inadequate access to certain aspects of care were also reported. This systematic review demonstrates that patients' perceptions of surveillance after HNC are mostly positive, feeling it provides reassurance. However, several studies report unmet needs, particularly regarding managing anxiety.

Lymphatic filariasis elimination in the Dominican Republic: History, progress, and remaining steps.

Lymphatic filariasis (LF) is a mosquito-transmitted parasitic disease that is a leading cause of disability globally. The island of Hispaniola, which the Dominican Republic shares with Haiti, accounts for approximately 90% of LF cases in the Americas region. In 1998, the Dominican Ministry of Public Health created the Program to Eliminate Lymphatic Filariasis (PELF) with the goal of eliminating LF transmission by 2020. Baseline mapping revealed 19 (12% of total) endemic municipalities clustered into three geographic foci (Southwest, La Ciénaga and East), with a total at-risk population of 262,395 people. Beginning in 2002, PELF sequentially implemented mass drug administration (MDA) in these foci using albendazole and diethylcarbamazine (DEC). In total, 1,174,050 treatments were given over three to five annual rounds of house-to-house MDA per focus with a median coverage of 81.7% (range 67.4%–92.2%). By 2018, LF antigen prevalence was less than 2% in all foci, thus meeting criteria to stop MDA and begin post-treatment surveillance (PTS). This success has been achieved against a shifting landscape of limited domestic funding, competing domestic public health priorities, and sporadic external donor support. Remaining steps include the need to scale-up morbidity management and disability prevention services for LF and to continue PTS until LF transmission is interrupted across Hispaniola.

Necessity of posttreatment surveillance for low-grade appendiceal mucinous neoplasms.

Low-grade appendiceal mucinous neoplasms (LAMNs) are generally treated by surgical resection, but posttreatment surveillance protocols are not well-established. The objectives of this study were to characterize posttreatment surveillance and determine the risk of recurrence following surgical resection of LAMN. Patients who underwent surgical resection of localized LAMNs in an 11-hospital regional healthcare system from 2000 to 2019 were identified. Posttreatment surveillance regimens were characterized, and rates of disease recurrence were evaluated. A total of 114 patients with LAMNs were identified. T-category was pTis for 92 patients (80.7%), pT3 for 7 (6.1%), pT4a for 14 (12.3%), and pT4b for 1 (0.9%). Two patients (1.8%) had a positive resection margin. Posttreatment surveillance was performed for 39 (34.2%) patients and consisted of office visits for 32 (82%) patients, computerized tomography imaging for 30 (77%), magnetic resonance imaging for 5 (13%), colonoscopy for 15 (38%), and serum tumor marker measurement for 12 (31%). After a mean follow-up duration of 4.7 years, no patients experienced tumor recurrence. Posttreatment surveillance is common among patients with LAMNs. However, no patients experienced tumor recurrence, regardless of T-category or margin status, suggesting that routine surveillance following surgical resection of LAMN may be unnecessary.

PO-1296 Usage of PET/CT as a post-treatment surveillance strategy in locoregionally advanced cervical cancer

PO-1296 Usage of PET/CT as a post-treatment surveillance strategy in locoregionally advanced cervical cancer

Imaging of Cervical Lymph Nodes in Thyroid Cancer: Ultrasound and Computed Tomography.

Sonographic evaluation of cervical lymph nodes in patients with thyroid malignancy is important both for preoperative staging and for post-treatment surveillance, and contrast-enhanced computed tomography plays a complementary role. Knowledge of anatomy and surgical approaches, combined with an understanding of the various imaging features that distinguish malignant from benign lymph nodes, allows for accurate staging, thereby enabling complete surgical initial resection.

Cell-Free Human Papillomavirus-DNA for Monitoring Treatment Response of Head and Neck Squamous Cell Carcinoma: Systematic Review and Meta-Analysis.

The aim of this study was to assess the value of cell-free human papillomavirus-DNA (cfHPV-DNA) as a diagnostic test for the post-treatment surveillance of patients with HPV-positive head and neck squamous cell carcinoma (HNSCC) through a systematic review and meta-analysis. Systematic review and meta-analysis. A literature search was conducted in three databases (MEDLINE, Embase, and Scopus) in January 2021. The population included patients with HPV-positive HNSCC. The intervention was the use of the repeated liquid biopsy with circulating HPV-DNA detection during follow-up. The outcome was to establish the value of cfHPV-DNA as a diagnostic test for the post-treatment surveillance of patients with HPV-positive HNSCC. Ten studies included in the meta-analysis provided a total of 457 patients with HPV-positive HNSCC. The meta-analytic study estimated the diagnostic performance of cfHPV-DNA as follows: pooled sensitivity and specificity of 0.65 (95% confidence interval [CI]: 0.40-0.84) and 0.99 (99% CI: 0.96-0.99), respectively; positive and negative likelihood ratios of 62.5 (99% CI: 22.9-170.2) and 0.05 (99% CI: 0.013-0.24), respectively; and pooled diagnostic odds ratio of 371.66 (99% CI: 60.4-2286.7). Currently, the follow-up protocol for HNSCC patients includes routine clinical evaluation and radiological imaging. Biomarkers to monitor this disease are not established. Considering its high specificity, cfHPV-DNA represents a potential confirmatory test in the case of positive positron emission tomography and computed tomography. In the near future, cfHPV-DNA could be used as a biomarker for monitoring the treatment response during the clinical trials of de-escalation therapy or immunotherapy. Larger sample sizes and the homologation of study protocols and methodology are needed to better establish its utility in the clinical practice. Laryngoscope, 132:560-568, 2022.

Evaluation of Integrated HPV DNA as Individualized Biomarkers for the Detection of Recurrent CIN2/3 during Post-Treatment Surveillance

Simple SummaryHPV-DNA integration into the host genome is a frequent step in cervical carcinogenesis and is considered to be a tumor-driving event. Viral integration sites are unique for each patient and could thus serve as highly specific molecular markers for the detection of recurrent disease. Unexpectedly, our study showed that integration sites as individualized biomarkers could not detect all recurrent pre-cancers (CIN2/3). Nevertheless, this is the first study which has identified and validated integration sites in a large number of CIN3 (n = 445) and as such has unraveled several novel findings: The integration frequency observed in CIN3 was much lower than anticipated (10.8% in CIN3 vs. 80% in cervical cancer). Moreover, in contrast to the monoclonal situation in cervical carcinoma, integrated HPV-DNA in CIN3 is most likely confined to clonally expanding subpopulations.Purpose: Post-treatment follow-up in women with cervical pre-cancers (CIN3) is mandatory due to relapse in up to 10% of patients. Standard follow-up based on hrHPV-DNA/cytology co-testing has high sensitivity but limited specificity. The aim of our prospective, multicenter, observational study was to test the hypothesis that an individualized viral-cellular-junction test (vcj-PCR) combined with cytology has a lower false positive rate for the prediction of recurrence compared to standard co-testing. Methods: Pre-surgical cervical swabs served for the identification of HPV16/18 DNA integration sites by next-generation-sequencing (NGS). Samples taken at 6, 12 and 24 months post-surgery were evaluated by cytology, hrHPV-DNA and the patients’ individual HPV-integration sites (vcj-PCR on the basis of NGS). Results: Integration sites were detected in 48 of 445 patients (10.8%), 39 of them had valid follow-up data. The false positive rate was 18.2% (95% CI 8.6–34.4%) for standard hrHPV/cytology at six months compared to 12.1% (95% CI 4.8–27.3%) for vcj-PCR/cytology, respectively (McNemar p = 0.50). Six patients developed recurrences (1 CIN2, 5 CIN3) during follow-up. Standard co-testing detected all, whereas vcj-PCR/cytology detected only five patients with recurrences. Data of 269 patients without evidence of HPV16/18 integration were subject to post-hoc analyses. Standard co-testing revealed a false positive rate of 15.7% (95% CI 11.7–20.7%) and predicted ten of fourteen recurrences at six months. Conclusions: Although highly specific on its own vcj-PCR could not detect all recurrent CIN2/3. Possible reasons for this unexpected result may be multifocal lesions, intratumoral heterogeneity with respect to HPV integration and/or incident CIN.

SP2-2 COVID-19 impact on the oncology practice in the USA

Coronavirus disease 2019 (COVID-19) has changed our lives and how we approach cancer in the USA. Unfortunately, cancer incidence will not change despite COVID-19. Starting from March 2020, the US had a significant impact on how we care for our patients. Cancer screening, diagnosis, treatment, and posttreatment surveillance in uninfected patients during the pandemic is something that we continue to explore the most efficient way to provide the care without risking the patients from COVID-19 and not providing the inferior care. Further, we need to make sure that we protect our healthcare providers from the COVID-19. I will provide my talk from a medical oncology practitioner's perspective, approaches, and issues that I have noted in the USA.

Published randomized controlled trials of surveillance in cancer patients - a systematic review.

With solid tumor cancer survivorship increasing, the number of patients requiring post-treatment surveillance also continues to increase. This highlights the need for evidence-based cancer surveillance guidelines. Ideally, these guidelines would be based on combined high-quality data from randomized controlled trials (RCTs). We present a systematic review of published cancer surveillance RCTs in which we sought to determine the feasibility of data pooling for guideline development.We carried out a systematic search of medical databases for RCTs in which adult patients with solid tumors that had undergone surgical resection with curative intent and had no metastatic disease at presentation, were randomized to different surveillance regimens that assessed effectiveness on overall survival (OS). We extracted study characteristics and primary and secondary outcomes, and assessed risk of bias and validity of evidence with standardized checklist tools.Our search yielded 32,216 articles for review and 18 distinct RCTs were included in the systematic review. The 18 trials resulted in 23 comparisons of surveillance regimens. There was a highlevel of variation between RCTs, including the study populations evaluated, interventions assessed and follow-up periods for the primary outcome. Most studies evaluated colorectal cancer patients (11/18, [61%]). The risk of bias and validity of evidence were variable and inconsistent across studies.This review demonstrated that there is tremendous heterogeneity among RCTs that evaluate effectiveness of different postoperative surveillance regimens in cancer patients, rendering the consolidation of data to inform high-quality cancer surveillance guidelines unfeasible. Future RCTs in the field should focus on consistent methodology and primary outcome definition.

Scaling-Down Mass Ivermectin Treatment for Onchocerciasis Elimination: Modeling the Impact of the Geographical Unit for Decision Making

BackgroundDue to spatial heterogeneity in onchocerciasis transmission, the duration of ivermectin mass drug administration (MDA) required for eliminating onchocerciasis will vary within endemic areas and the occurrence of transmission “hotspots” is inevitable. The geographical scale at which stop-MDA decisions are made will be a key driver in how rapidly national programs can scale down active intervention upon achieving the epidemiological targets for elimination.MethodsWe used 2 onchocerciasis models (EPIONCHO-IBM and ONCHOSIM) to predict the likelihood of achieving elimination by 2030 in Africa, accounting for variation in preintervention endemicity levels and histories of ivermectin treatment. We explore how decision making at contrasting geographical scales (community vs larger scale “project”) changes projections on populations still requiring MDA or transitioning to post-treatment surveillance.ResultsThe total population considered grows from 118 million people in 2020 to 136 million in 2030. If stop-MDA decisions are made at project level, the number of people requiring treatment declines from 69–118 million in 2020 to 59–118 million in 2030. If stop-MDA decisions are made at community level, the numbers decline from 23–81 million in 2020 to 15–63 million in 2030. The lower estimates in these prediction intervals are based on ONCHOSIM, the upper limits on EPIONCHO-IBM.ConclusionsThe geographical scale at which stop-MDA decisions are made strongly determines how rapidly national onchocerciasis programs can scale down MDA programs. Stopping in portions of project areas or transmission zones would free up human and economic resources.

Sinonasal Squamous Cell Carcinoma, a Narrative Reappraisal of the Current Evidence.

Simple SummarySinonasal squamous cell carcinomas are a group of diverse tumors affecting the nasal cavity and paranasal sinuses. As a direct consequence of their rarity and heterogeneity, diagnosis is challenging, and treatment does not follow universally accepted protocols. Though surgery represents the mainstay of treatment, neoadjuvant and adjuvant therapies have pivotal roles in improving outcomes of patients treated with curative intent. Indications to endoscopic surgery have been expanding over the last three decades, but a considerable number of patients affected by sinonasal squamous cell carcinoma still need open surgical procedures. Management of the neck in patients affected by sinonasal squamous cell carcinoma is controversial. Curative-intended treatment of recurrent and/or metastatic tumors, alongside palliation of uncurable cases, represent poorly explored aspects of this disease.Sinonasal squamous cell carcinoma is a rare tumor affecting the nasal cavity and paranasal sinuses. Several aspects of this disease, ranging from epidemiology to biology, pathology, diagnosis, staging, treatment, and post-treatment surveillance are controversial, and consensus on how to manage this sinonasal cancer is lacking. A narrative literature review was performed to summarize the current evidence and provide the reader with available data supporting the decision-making process in patients affected by sinonasal squamous cell carcinoma, alongside the authors’ personal opinion on the unsolved issues of this tumor. The review has highlighted several advances in molecular definition of epithelial cancers of the sinonasal tract. Surgery represents the pivot of treatment and is performed through an endoscopic transnasal approach whenever feasible. Open surgery is required for a large proportion of cases. Reconstruction of the defect follows principles of skull base and cranio-maxillo-facial reconstruction. Chemotherapy is given as neoadjuvant treatment or concomitantly to radiotherapy. Photon-based radiation therapy has a crucial role in the adjuvant setting. Particle therapy is providing promising results. Management of the neck should be planned based on the presence of clinically appreciable metastases, primary tumor extension, and need for recipient vessels. Biotherapy and immunotherapy are still underexplored therapeutical modalities.

Highlights from the literature

Radiofrequency ablation (RFA) is key in the therapy of early neoplasia in Barrett’s oesophagus (BO). However, a small proportion of patients experience neoplastic recurrence (NR) after complete eradication of intestinal...

Clinicopathological and prognostic features of young onset patients with middle-low rectal cancer received neoadjuvant chemoradiotherapy

Objective: To explore the clinicopathological and prognostic features of young onset patients with middle-low rectal cancer who received neoadjuvant chemoradiotherapy (NCRT). Methods: After NCRT, a total of 441 patients with primary middle-low rectal cancer treated with radical surgery at the Cancer Hospital, Chinese Academy of Medical Sciences (CHCAMS) from January 2004 to December 2016 were included. According to the age of disease onset, the patients were divided into the young group (51cases) and the middle-old group (390 cases), and the clinicopathological characteristics and survival of these patients were analyzed. Results: In the young group, 68.6% of patients received radical surgery within 7 weeks after NCRT, which was higher than 52.8% in the middle-old group (P=0.047). The stage ypTNM Ⅲ in the young group was 51.0%, higher than 34.1% in the middle-old group (P=0.027). The stage ypN+ in the young group was 51.0%, higher than 34.1% in the middle-old group (P=0.047), The incidence of disease progression in the young group was 39.2%, higher than 25.1% in the middle-old group (P=0.049). The incidence of distant metastasis in the young group was 35.3%, higher than 21.5% in the middle-old group(P=0.044). Most cases of disease progression occurred in the first 3 years after surgery for the young group, especially in the second year after surgery, the incidence of disease progression in the young group was 55.0%, higher than 26.5% in middle-old group (P=0.025). The 3-year and 5-year disease-free survival (DFS) rates for the young group were 63.7% and 58.2%, lower than 81.0% and 74.3% in the middle-old group (P=0.016), respectively. The 3-year and 5-year overall survival in the middle-old group (OS) rates for the young group were 85.4% and 69.2%, lower than 93.6% and 84.1% in the middle-old group (P=0.033), respectively. The multivariate analysis showed that, response of primary tumor (HR=4.804, 95% CI: 1.360-16.973) and total number of dissected lymph nodes (HR=4.336, 95% CI: 1.739-10.809) in the young group were independent prognostic factors related to DFS. The total dissected number of lymph nodes(HR=3.295, 95% CI: 1.076-10.091)was an independent prognostic factor related to OS. In the middle-old group, response of primary tumor (HR=2.626, 95% CI: 1.354-5.091), ypTNM stage (ypTNM Ⅲ: HR=5.837, 95% CI: 2.968-11.479) and tumor location distance from the anal verge (HR=0.500, 95% CI: 0.308-0.812) were independent prognostic factors related to DFS. Lymphovascular invasion (HR=0.500, 95% CI: 0.308-0.812) and ypTNM stage (ypTNM Ⅲ: HR=16.322, 95% CI: 5.049-52.771) were independent prognostic factors related to OS. Conclusions: Young onset rectal cancer patients are associated with shorter operation time interval, advanced pathological stage and poorer prognosis. More intensive adjuvant treatment and post-treatment surveillance should be conducted to young onset rectal cancer with NCRT.

Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL): Quantifying the direct economic costs of post-treatment radiological surveillance.

e19574 Background: Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) was recognised by the WHO in 2016 as a rare sub-type of peripheral T-cell, non-Hodgkin lymphoma (NHL), characterized by an indolent clinical course and excellent prognosis. Little evidence exists on the role of post-treatment imaging surveillance with variable practices across the world. Recent UK guidelines recommend that routine surveillance imaging should not be offered to BIA-ALCL patients, in line with national/international recommendations for other NHLs. The aim of this study was to quantify the direct economic costs (DEC) of post-treatment BIA-ALCL routine radiological surveillance at our institution compared to the DEC if UK guidelines were followed. Methods: Following IRB approval a retrospective analysis of a prospectively maintained database of BIA-ALCL patients at The Royal Marsden Hospital was performed. DECs were estimated using current (2020) NHS tariffs for radiological investigations. Imaging undertaken for symptomatic problems/non-BIA-ALCL related concerns was excluded. Results: Eleven patients [median age: 49 years (IQR 45-52)] were treated for BIA-ALCL between 2015-2020 following cosmetic augmentation (n = 6) or breast reconstruction (n = 5). Median time from first implant surgery to BIA-ALCL diagnosis was 11 years (IQR 8-12). Patients presented with effusion (n = 7), mass (n = 2) or effusion and mass (n = 2). One patient had neoadjuvant CHOP/brentuximab, all 11 had explantation with en bloc total capsulectomy, 1 had adjuvant CHOP. Median follow-up was 38 months (IQR 12-47) with no local or distant relapses. Two patients did not have any radiological surveillance and 1 had follow-up elsewhere. The remaining 8 patients had a combination of PET/CT (n = 10), CT (n = 2), breast ultrasound (n = 6), mammogram (n = 4) and breast MRI (n = 1) as routine imaging follow-up not guided by clinical concerns. This represents evolving practice at our institution as the UK guidelines were published in 2021. Total cost of routine imaging surveillance was £10,396 ($14,396) with median cost of £1,953 ($2,705) per patient [IQR £526-2029 ($728-2,810)]. This cost could have been saved based on current guidelines recommending no routine surveillance for patients with no symptoms or clinical concerns. Conclusions: This data demonstrates that omission of routine post-treatment imaging surveillance, as per the recent UK guidelines, would result in a median DEC saving of £1,953 ($2,705) per patient at our institution. No local or distant relapses where identified within the follow-up period, in line with the existing literature suggesting BIA-ALCL has a very low risk of relapse and excellent prognosis. These findings provide a value-based analysis to further support the recommendation not to perform routine post-treatment imaging surveillance in patients with BIA-ALCL.

Mathematical predication models to optimize post-treatment surveillance in HPV-associated oropharyngeal cancer.

6027 Background: In this study we develop post-treatment imaging surveillance schedules for locally advanced oropharyngeal carcinoma (OPC) specific to the unique recurrence patterns of tumor stage and HPV status, using mathematical models. Current post-treatment imaging surveillance recommendations for OPC are not evidence based. The exception is the use of a positron emission tomography (PET) scan at 3 months post-treatment, after which practice across institutions diverge. An optimized and personalized surveillance schedule for OPC patients can minimize costs and diagnostic delays. Methods: A Markov multi-state model defining local and distant recurrences was trained using 2159 patients from the National Cancer Database. Patients from 2010-2015 treated at an academic or major cancer center with curative radiotherapy were included. Tumors must have been stage III to IVB (AJCC 7th edition) with known p16/HPV status. Model performance was then successfully externally validated using the 2016 International Collaboration on Oropharyngeal cancer Network for Staging (ICON-S) study. Optimized radiographic surveillance schedules were created using this model, assuming a PET at month 3 and including 0 to 6 additional computed tomography (CT) scans of the neck and chest. Optimization was done for minimization of latency, defined as time between disease recurrence and radiographic discovery. Results: Model-selected schedules varied significantly from commonly utilized-surveillance schedules (such as imaging every 3 months within the first year from treatment) and showed lower mean diagnostic latency for every stage and HPV status (shown in Table). In the lowest risk cohort (Stage III HPV+), the optimized schedule had a sensitivity of 65% and latency of 3.1 months. In the highest risk group (Stage IVB HPV-), the optimized schedule had a sensitivity of 76% and latency of 1.9 months. Conclusions: Mathematical model optimization for HPV status and stage is feasible and produces non-intuitive results. These results could be used to inform surveillance if payors reimburse for fewer total scans. Across all cohorts, each added CT scan increases surveillance sensitivity and decreases latency. Incorporation of physical exam and direct visualization results into the model are still needed. Future steps include cost effectiveness research and prospective clinical trials.[Table: see text]

The other side of screening: predictors of treatment and follow-up for anal precancers in a large health system.

Anal cancer disproportionately affects people with HIV (PWH). High-grade squamous intraepithelial lesions (HSIL) are cancer precursors and treating them might prevent anal cancer. Data on adherence to HSIL treatment and surveillance is limited but needed to identify deficiencies of screening strategies. We collected data on high-resolution anoscopy (HRA) attendance and outcomes from 2009 to 2019 in a large urban anal cancer-screening program. Patients with an initial HSIL diagnosis were followed for return for HSIL electrocautery ablation within 6 months of index HSIL diagnosis, and follow-up HRA within 18 months of index HSIL diagnosis. We also evaluated predictors of these outcomes in univariable and multivariable analyses. One thousand one hundred and seventy-nine unique patients with an anal HSIL diagnosis were identified and 684 (58%) returned for electrocautery ablation. Of those treated, only 174 (25%) and only 9% of untreated HSIL patients (47 of 495) underwent surveillance HRA within 18 months of index HSIL diagnosis. In multivariable analyses, black patients and PWH regardless of virologic control were less likely to undergo HSIL ablation within 6 months of HSIL diagnosis whereas patients with commercial insurance were more likely to be treated within 6 months of diagnosis. Among treated HSIL patients, PWH with viremia had a lower likelihood of engaging in post-treatment surveillance within 18 months of HSIL diagnosis. Even in large specialized anal cancer screening programs adherence to HSIL treatment and surveillance is low. Psychosocial and economic determinants of health may impact retention in care. Addressing both personal and structural barriers to patient engagement may improve the effectiveness of anal cancer screening.