Effectiveness of educational and psychological survivorship interventions to improve health-related quality of life outcomes for men with prostate cancer on androgen deprivation therapy: a systematic review

OBJECTIVES

Androgen deprivation therapy (ADT), a common treatment for prostate cancer, has debilitating impacts on physical and psychological quality of life. While some interventions focus on managing the physical side effects of ADT, there is a paucity of interventions that also address psychosocial and educational needs. The objective of this systematic review was to identify psychological and educational survivorship interventions targeting health-related quality of life (HRQoL) outcomes in men on ADT.

DESIGN

A systematic review of randomised controlled trials.

DATA SOURCES

Web of Science, Cochrane, EBSCO Host, PubMed, SCOPUS from inception (1984) to 28 January 2023.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Psychological and/or educational survivorship interventions targeting HRQoL outcomes for men on ADT; minimum 80% of participants on ADT; used a validated HRQoL outcome measure; published in English in a peer-reviewed journal.

DATA EXTRACTION AND SYNTHESIS

Data extraction using pre-specified study criteria was conducted. Heterogeneity of eligible studies precluded a meta-analysis.

RESULTS

A total of 3381 publications were identified with eight meeting the criteria. Interventions were either psychological with a cognitive behavioural approach (n=4), or educational with (n=2) or without (n=2) psychoeducational components.Two studies reported a statistically significant improvement using a specific HRQoL measure. Most studies were not adequately powered and/or included small sample sizes limiting the conclusions that can be drawn on effectiveness. The most effective interventions were (i) individually based, (ii) educational with a psychoeducational component, (iii) supplemented with information packages and/or homework and (iv) included personalised needs assessments.

CONCLUSION

There is a paucity of literature reporting psychological and educational survivorship interventions targeting HRQoL outcomes for men on ADT. What is urgently needed are person-centred survivorship interventions that are flexible enough to identify and address individual needs, taking into account the impact ADT has on both physical and psychological quality of life.

PROSPERO REGISTRATION NUMBER

CRD4202230809.

Early Exposure to Orthopaedic Surgery

INTRODUCTION

Disparities in early orthopaedic experiences among medical students prompt a critical examination of factors influencing the availability and nature of these exposures. While the current body of literature underscores the significance of early surgical exposure and mentorship in medical education, a notable gap exists in investigating early orthopaedic exposure and its specific impact on students from diverse backgrounds.

METHODS

A 16-item questionnaire, approved by our institutional review board, was administered to fourth-year medical students (MS4) and first-year orthopaedic residents (PGY-1) across U.S. orthopaedic surgery programs during the 2022-2023 application cycle. The questionnaire assessed participants' initial orthopaedic exposures and factors influencing interest in the field. Two-proportion Z-test analyses were conducted to analyze the data, and thematic analysis was used to assess qualitative data involving free-response questions.

RESULTS

Out of 72 total respondents, the study revealed that 83% of respondents encountered orthopaedics before medical school, with initial exposures stemming from various sources such as familial connections (28%), athletics (17%), and high school or college exposures (15%), including shadowing, athletics participation, and occupation-related exposure. Disparities were observed in the availability of orthopaedic mentors and early exposure opportunities between demographic groups. Statistical analyses highlighted significant differences in access to mentors who reflected students' identities between male and non-male participants (70% vs. 39%, p=0.02) and between white and non-white participants (69% vs. 36%, p=0.02). White participants were also more likely to first interact with a surgeon who treated them or their family members than non-white participants (35% vs 7%, p=0.04). Non-white participants were more likely than white participants to come by their first orthopaedic opportunity by searching for it independently (21% vs. 4%, p=0.03). Family and friend connections in orthopaedics were found to be influential in motivating students to pursue orthopaedics, with 40% of respondents indicating personal connections in medicine and 12% reporting family members who are orthopaedic surgeons. Research experiences were identified as important contributors to students' initial interest and motivation to ultimately pursue orthopaedics, especially those with diverse backgrounds.

CONCLUSION

The findings underscore the importance of early orthopaedic exposures in shaping students' interest in the field, highlighting the need for more immersive pre-clinical year opportunities and enhanced mentorship programs. Addressing disparities in mentorship access and early exposure opportunities requires systemic changes and increased support for underrepresented minorities in orthopaedics. Initiatives like mentorship programs and research opportunities can help bridge gaps in access to early orthopaedic experiences. Medical schools should prioritise targeted early access to orthopaedic exposures for all students, regardless of background. This initiative aims to promote inclusivity and cultivate a more diverse orthopaedic workforce capable of meeting the evolving healthcare needs of society.

Prostate Cancer Survivorship Essentials for men with prostate cancer on androgen deprivation therapy: protocol for a randomised controlled trial of a tele-based nurse-led survivorship care intervention (PCEssentials Hormone Therapy Study)

INTRODUCTION

Androgen deprivation therapy (ADT) is commonly used to treat men with locally advanced or metastatic prostate cancer. Men receiving ADT experience numerous side effects and frequently report unmet supportive care needs. An essential part of quality cancer care is survivorship care. To date, an optimal effective approach to survivorship care for men with prostate cancer on ADT has not been described. This protocol describes a randomised trial of tele-based nurse-led survivorship that addresses this knowledge gap: (1) determine the effectiveness of a nurse-led survivorship care intervention (PCEssentials), relative to usual care, for improving health-related quality of life (HR-QoL) in men with prostate cancer undergoing ADT and (2) evaluate PCEssentials implementation strategies and outcomes, including cost-effectiveness, compared with usual care.

METHODS AND ANALYSIS

This is an effectiveness-implementation hybrid (type 1) trial with participants randomised to one of two arms: (1) minimally enhanced usual care and (2) nurse-led prostate cancer survivorship essentials (PCEssentials) delivered over four tele-based sessions, with a booster session 5 months after session 1. Eligible participants are Australian men with prostate cancer commencing ADT and expected to be on ADT for a minimum of 12 months. Participants are followed up at 3, 6 and 12 months postrecruitment. Primary outcomes are HR-QoL and self-efficacy. Secondary outcomes are psychological distress, insomnia, fatigue and physical activity. A concurrent process evaluation with participants and study stakeholders will be undertaken to determine effectiveness of delivery of PCEssentials.

ETHICS AND DISSEMINATION

Ethics approval was obtained from the Metro South Health HREC (HREC/2021/QMS/79429). All participants are required to provide written informed consent. Outcomes of this trial will be published in peer-reviewed journals. The findings will be presented at conferences and meetings, local hospital departments, participating organisations/clinical services, and university seminars, and communicated at community and consumer-led forums.

TRIAL REGISTRATION NUMBER

ACTRN12622000025730.

Are Different Modes of Weight Loss Associated with Survival in Oropharyngeal Cancer?

PURPOSE/OBJECTIVE(S)

Patients with oropharyngeal squamous cell carcinomas (OPSCC) often lose weight during radical radiotherapy (RT). Nutritional intervention is required in case of severe weight loss. However, weight loss does not provide full insight into body composition changes. Muscle mass is emerging as an important prognostic factor in cancer patients. We employed on-treatment cone-beam CT (CBCT) scans to monitor muscle mass and weight loss under the hypothesis that different modes of weight loss exist and may impact overall survival (OS).

MATERIALS/METHODS

A retrospective analysis of 197 OPSCC patients treated with definitive or adjuvant (chemo)RT. Weekly weight measurements & CBCTs were collected. Patients were included if at least two time-points were available and the interval between the first and last was between 15-50 days. CBCTs were normalized to account for calibration differences between treatment machines. An in-house deep-learning model automatically segmented the skeletal muscle compartment at C3 on all CBCTs. Segmentations were visually checked and failures removed. Skeletal muscle volume (SMV, in mm3) was extracted after thresholding for intra-muscular fat. Relative changes in weight & SMV were then calculated. Linear models were fitted to each trajectory for every patient and slopes were estimated. The following weight & SMV categories were defined to generate equal groups: lost (more than 0.4 standard deviations (SDs) below the mean (M)), maintained (within +/- 0.4 SDs of M) or gained (more than 0.4 SDs above the M). Table 1 highlights the nine modes of body composition change. The prognostic value of these was investigated in multivariable Cox models accounting for age, sex, disease stage, oropharynx subsite, smoking status, performance status (PS), tumor p16 status, baseline weight & SMV, and treatment prescribed. The primary endpoint was OS.

RESULTS

Mean weight & SMV changes during treatment were -0.047±0.001% & -0.044±0.019% per day. In multivariable analysis, gaining weight & losing SMV was identified as a significant risk factor for OS (p = 0.01, hazard ratio [95% CI]: 4.59 [1.40-15.10]). In this sub-group, mean weight & SMV change were +0.054±0.008% & -0.396±0.030% per day. PS>2 (p<0.001) & lower baseline weight (p = 0.02) were also significantly associated with OS.

CONCLUSION

Patients losing substantial SMV but mildly gaining weight have significantly worse OS than others. This suggests there exists a group of patients where nutritional support is needed, but not offered because they maintain weight during treatment. Although our results need validation, continual monitoring of muscle condition during RT would allow these patients to be identified and promptly targeted for nutritional support.

Registration of essential medicines in Kenya, Tanzania and Uganda: a retrospective analysis

OBJECTIVES

To audit national drug registers (NDRs) in Kenya, United Republic of Tanzania and Uganda with respect to national Essential Medicine Lists (EMLs) and to conduct an analysis of highly registered products including a sub-analysis of highly registered antimicrobial products.

DESIGN

Retrospective analysis of registration of essential medicines and medicinal products on NDRs as of February 2018.

SETTING

Not applicable.

PARTICIPANTS

None.

MAIN OUTCOME MEASURES

Registration status of essential medicines by country, essential medicine status of registered products by country and medicines with more than 50 registrations across all three countries.

RESULTS

A high proportion of essential medicines are not registered: Kenya 28% (175/632), United Republic of Tanzania 50% (400/797) and Uganda 40% (266/663). Of registered products on the NDRs, more than half are not essential: Kenya 71% (4350/6151), United Republic of Tanzania 64% (2278/3590) and Uganda 58% (2268/3896). When the three NDRs were combined, there were 42 medicines with over 50 registered products, accounting for 30% (4153/13637) of products, many of which were non-essential.

CONCLUSIONS

Non-registration of essential medicines is a barrier to availability. Over-registration of medicines, particularly non-essential medicines, diverts regulatory resources towards registering non-priority and, sometimes, clinically sub-optimal medicines. The East African Community Medicines Registration Harmonization Project has the potential to improve access to key medicines if registration of essential medicines is prioritised and registration of non-essential medicines is restricted.

Different niches for stem cells carrying the same oncogenic driver affect pathogenesis and therapy response in myeloproliferative neoplasms

Aging facilitates the expansion of hematopoietic stem cells (HSCs) carrying clonal hematopoiesis-related somatic mutations and the development of myeloid malignancies, such as myeloproliferative neoplasms (MPNs). While cooperating mutations can cause transformation, it is unclear whether distinct bone marrow (BM) HSC-niches can influence the growth and therapy response of HSCs carrying the same oncogenic driver. Here we found different BM niches for HSCs in MPN subtypes. JAK-STAT signaling differentially regulates CDC42-dependent HSC polarity, niche interaction and mutant cell expansion. Asymmetric HSC distribution causes differential BM niche remodeling: sinusoidal dilation in polycythemia vera and endosteal niche expansion in essential thrombocythemia. MPN development accelerates in a prematurely aged BM microenvironment, suggesting that the specialized niche can modulate mutant cell expansion. Finally, dissimilar HSC-niche interactions underpin variable clinical response to JAK inhibitor. Therefore, HSC-niche interactions influence the expansion rate and therapy response of cells carrying the same clonal hematopoiesis oncogenic driver.

Ruxolitinib Versus Best Available Therapy for Polycythemia Vera Intolerant or Resistant to Hydroxycarbamide in a Randomized Trial

PURPOSE

Polycythemia vera (PV) is characterized by JAK/STAT activation, thrombotic/hemorrhagic events, systemic symptoms, and disease transformation. In high-risk PV, ruxolitinib controls blood counts and improves symptoms.

PATIENTS AND METHODS

MAJIC-PV is a randomized phase II trial of ruxolitinib versus best available therapy (BAT) in patients resistant/intolerant to hydroxycarbamide (HC-INT/RES). Primary outcome was complete response (CR) within 1 year. Secondary outcomes included duration of response, event-free survival (EFS), symptom, and molecular response.

RESULTS

One hundred eighty patients were randomly assigned. CR was achieved in 40 (43%) patients on ruxolitinib versus 23 (26%) on BAT (odds ratio, 2.12; 90% CI, 1.25 to 3.60; P = .02). Duration of CR was superior for ruxolitinib (hazard ratio [HR], 0.38; 95% CI, 0.24 to 0.61; P < .001). Symptom responses were better with ruxolitinib and durable. EFS (major thrombosis, hemorrhage, transformation, and death) was superior for patients attaining CR within 1 year (HR, 0.41; 95% CI, 0.21 to 0.78; P = .01); and those on ruxolitinib (HR, 0.58; 95% CI, 0.35 to 0.94; P = .03). Serial analysis of JAK2V617F variant allele fraction revealed molecular response was more frequent with ruxolitinib and was associated with improved outcomes (progression-free survival [PFS] P = .001, EFS P = .001, overall survival P = .01) and clearance of JAK2V617F stem/progenitor cells. ASXL1 mutations predicted for adverse EFS (HR, 3.02; 95% CI, 1.47 to 6.17; P = .003). The safety profile of ruxolitinib was as previously reported.

CONCLUSION

The MAJIC-PV study demonstrates ruxolitinib treatment benefits HC-INT/RES PV patients with superior CR, and EFS as well as molecular response; importantly also demonstrating for the first time, to our knowledge, that molecular response is linked to EFS, PFS, and OS.

Coronial postmortem reports and indirect COVID-19 pandemic-related mortality

AIMS

Widespread disruption of healthcare services and excess mortality not directly attributed to COVID-19 occurred between March and May 2020. We undertook the first UK multicentre study of coroners' autopsies before and during this period using postmortem reports.

METHODS

We reviewed reports of non-forensic coroners' autopsies performed during the first COVID-19 lockdown (23 March to 8 May 2020), and the same period in 2018. Deaths were categorised as natural non-COVID-19, COVID-19-related, non-natural (suicide, drug and alcohol-related, traumatic, other). We provided opinion regarding whether delayed access to medical care or changes in behaviour due to lockdown were a potential factor in deaths.

RESULTS

Seven centres covering nine coronial jurisdictions submitted a total of 1100 coroners' autopsies (498 in 2018, 602 in 2020). In only 54 autopsies was death attributed to COVID-19 (9%). We identified a significant increase in cases where delays in accessing medical care potentially contributed to death (10 in 2018, 44 in 2020). Lockdown was a contributing factor in a proportion of suicides (24%) and drug and alcohol-related deaths (12%).

CONCLUSIONS

Postmortem reports have considerable utility in evaluating excess mortality due to healthcare and wider societal disruption during a pandemic. They provide information at an individual case level that is not available from assessment of death certification data. Detailed evaluation of coroners' autopsy reports, supported by appropriate regulatory oversight, is recommended to mitigate disruption and indirect causes of mortality in future pandemics. Maintaining access to healthcare, including substance misuse and mental health services, is an important consideration.

Late-Stage Metastatic Melanoma Emerges through a Diversity of Evolutionary Pathways

Understanding the evolutionary pathways to metastasis and resistance to immune-checkpoint inhibitors (ICI) in melanoma is critical for improving outcomes. Here, we present the most comprehensive intrapatient metastatic melanoma dataset assembled to date as part of the Posthumous Evaluation of Advanced Cancer Environment (PEACE) research autopsy program, including 222 exome sequencing, 493 panel-sequenced, 161 RNA sequencing, and 22 single-cell whole-genome sequencing samples from 14 ICI-treated patients. We observed frequent whole-genome doubling and widespread loss of heterozygosity, often involving antigen-presentation machinery. We found KIT extrachromosomal DNA may have contributed to the lack of response to KIT inhibitors of a KIT-driven melanoma. At the lesion-level, MYC amplifications were enriched in ICI nonresponders. Single-cell sequencing revealed polyclonal seeding of metastases originating from clones with different ploidy in one patient. Finally, we observed that brain metastases that diverged early in molecular evolution emerge late in disease. Overall, our study illustrates the diverse evolutionary landscape of advanced melanoma.

SIGNIFICANCE

Despite treatment advances, melanoma remains a deadly disease at stage IV. Through research autopsy and dense sampling of metastases combined with extensive multiomic profiling, our study elucidates the many mechanisms that melanomas use to evade treatment and the immune system, whether through mutations, widespread copy-number alterations, or extrachromosomal DNA. See related commentary by Shain, p. 1294. This article is highlighted in the In This Issue feature, p. 1275.

Supportive interventions for carers of men with prostate cancer: systematic review and narrative synthesis

PURPOSE

The objective of this study was to summarise the literature on current interventions available for carers of men with prostate cancer and analyse the outcomes of these interventions in supporting carers' needs.

METHODS

A systematic review was conducted, searching databases MEDLINE, PsycINFO, CINAHL, Scopus and Cochrane, using terms related to prostate cancer, carers and interventions. Randomised controlled trials and non-randomised controlled trials of interventions for informal carers with or without patients were included. Data were analysed using descriptive and frequency statistics; interventions and their impact on carers' outcomes were reported on narratively. The SwiM guidelines were applied to guide data synthesis.

RESULTS

Overall, 24 articles were included in the review. On average, participants were spouses (92%) and women (97%). Interventions largely rwere delivered face-to-face (42%) or used a combination of face to face and online modalities (38%). Two-thirds (63%) showed a significant improvement in carer's outcomes including psychological, sexual, physical and relationship/marital. The majority of studies (79%) tailored contents to carers' circumstances, most within a couples counselling format. Over one-third (42%) of studies focused on a range of supportive care needs, most commonly were psychological (58%), sexual (42%) and informational (25%).

CONCLUSIONS

Interventions for carers of men with prostate cancer were largely face to face, patient-spouse focused and two-thirds had some measurable impact on carer's outcomes. Research continues to underserve other patient-carer roles, including non-spousal carers. Interventions delivered solely for carers are required to meet gaps in care, and determine the impact on carer outcomes. Further research and more targeted interventions are needed.

PROSPERO REGISTRATION NUMBER

CRD42021249870.

Evaluation of two temperature storage conditions for full blood count samples from Lifeblood's donors

BACKGROUND AND OBJECTIVES

Lifeblood completes full blood count samples for selected donors to assess their suitability for future donations. Removing the current practice for refrigerated (2-8°C) storage and aligning with room temperature (20-24°C) storage of other donor blood samples would produce significant efficiencies in blood donor centres. This study aimed to compare full blood count results under two temperature conditions.

MATERIALS AND METHODS

Paired full blood count samples were collected from 250 whole blood or plasma donors. These were stored either refrigerated or room temperature for testing on arrival at the processing centre and the following day. The primary outcomes of interest included differences between mean cell volume, haematocrit, platelet count, white cell and differential counts, and the need to produce blood films, based on existing Lifeblood criteria.

RESULTS

A statistically significant (p < 0.05) difference for most full blood count parameters results was found between the two temperature conditions. The number of blood films required was similar under each temperature condition.

CONCLUSION

The clinical significance of the small numerical differences in results is considered minimal. Furthermore, the number of blood films required remained similar under either temperature condition. Given the significant reductions in time, processing and costs associated with room temperature over refrigerated processing, we recommend a further pilot study to monitor the broader impacts, with the intent to implement national storage of full blood count samples at room temperature within Lifeblood.

The Combination of Fractional Tendon Lengthening and the Wide Awake, Local Anesthesia, No Tourniquet Technique for Secondary Tendon Reconstruction

Rupture is a major concern after primary flexor tendon repair. The predominant treatment for rupture of the primary repair is immediate surgical exploration and repeat repair. However, repeat repair is challenging, including achieving ideal tension in the flexor mechanism. Further, immediate repeat repair is associated with poor outcomes, particularly in the small finger. As such, there is a need to improve both the technique and outcomes of repeat repair of primary flexor tendon rupture. We present a case of primary flexor tendon repair rupture treated with a novel combination of fractional tendon lengthening and the wide awake, local anesthesia, no tourniquet technique. A combination of these techniques has multiple benefits. An intraoperative, dynamic assessment of the digits enables immediate optimization of the repair. Further, these techniques allow for better intraoperative patient education and communication, increasing the likelihood of adherence to postoperative therapy and better overall outcomes.

The cycle ergometer test is not a reliable alternative to the countermovement jump in the assessment of power output

Background

Rugby union is a physically demanding collision sport that requires optimal neuromuscular function for maximal power output, with mechanical power an integral component of performance. Peak power (P_p) and relative P_p are parameters of neuromuscular function commonly assessed through the countermovement jump (CMJ) as a measure of fatigue. The Wattbike cycle ergometer test (CET) is a non-load bearing method of evaluating lower limb power. The cost-effective CET could therefore offer a viable alternative to the CMJ.

Objectives

This study aimed to determine the concurrent validity of the CMJ and CET.

Methods

Thirty-eight professional rugby union players performed twelve CMJs on a force platform with four loads (bodyweight: BW-CMJ; 20kg: 20-CMJ; 40kg: 40-CMJ and 60kg: 60-CMJ) and a six second peak power (6PPO) CET assessment on a Wattbike ergometer.

Results

CMJ power outputs were [BW-CMJ: P_p - 3101±648 W; 20-CMJ: P_p - 2724±513 W; 40-CMJ: P_p - 2490±496 W; 60-CMJ: P_p - 2238±366 W] and CET [P_p - 1310±161 W]. None of the CMJ-P_p values showed relationships with any CET power variables. Large (r = 0.51-0.63; p = 0.000 - 0.001) relationships were found to be between relative CMJ and relative CET power outputs. Bland-Altman plots, which were used to determine the level of agreement between the two assessments, showed the agreement between the tests was poor.

Conclusion

Though positive relationships existed between relative CMJ and relative CET power variables, analyses of the level of agreement in the Bland-Altman plots suggest that the two power assessment methods are not interchangeable measures of power.

Differential inhibition of T cell receptor and STAT5 signalling pathways determines the immunomodulatory effects of dasatinib in chronic phase chronic myeloid leukemia

Dasatinib is a multi-kinase inhibitor with activity against the SRC kinase LCK, which plays a critical role in T-cell receptor signalling. Dasatinib, initially developed as an immunosuppressive agent, is by contrast, also noted to result in enhanced tumour immunity in a subset of patients. We studied the impact of dasatinib in CML patients and compared with patients taking other TKI and healthy controls. We found that patients on dasatinib showed inhibition of both TCR and STAT5 signalling pathways, and reduced expression of T effector pro-inflammatory cytokines. In addition, dasatinib induced selective depletion of Tregs and effector Tregs, particularly in patients with clonal expansion of effector CD8+ T-cells, who demonstrated greater and preferential inhibition of Treg TCR intracellular signalling. In addition, we show that dasatinib selectively reduces Treg STAT5 phosphorylation via reduction of IL-2, in relation with the marked reduction of plasma IL-2 levels in patients taking dasatinib. Finally, patients on other TKI had significantly increased TCR signalling in TIM3+ cells compared to patients taking dasatinib, suggesting that chronic SRC kinase inhibition by dasatinib may play a role in preventing TIM-3 mediated T cell exhaustion and preserve anti-tumour immunity. These data provide further insight into the selective immunomodulatory effects of dasatinib and its potential use for pharmacologic control of immunotherapies.

How Are Radial Height and Radial Shortening Defined in the Treatment of Distal Radius Fractures? A Critical Review

BACKGROUND

Radial height is a radiographic parameter used to guide the treatment of distal radius fractures. However, it is often used synonymously with other terms, and there are substantial discrepancies in its measurement/definition. These discrepancies can alter the measurement of radial height and affect treatment decisions. The purpose of this review is to identify the different definitions of radial height in the literature relevant to distal radius fractures.

METHODS

A literature review was conducted in the PubMed/MEDLINE database from inception to 2022. Full-length, English-language studies that pertained to distal radius fractures and reported radial height as a recorded measurement were included. The method of radial height measurement (definition) was extracted from included studies. Level of evidence was determined by the Oxford Centre for Evidence-based Medicine Levels of Evidence tool.

RESULTS

A total of 385 studies were identified. Of these, 183 (47.5%) did not provide a definition for radial height. Of the studies that defined radial height, 50.9% (103/202) measured radial height from the radial styloid to the distal ulna, 10.9% (22/202) measured from the radial styloid to the distal radius, and 29.2% (59/202) were "other" definitions.

CONCLUSIONS

There is substantial discrepancy in the way that radial height is measured and reported. We advocate for a standardized measurement of radial height (synonymous with radial length) from the radial styloid to the distal ulnar articular surface. Radial shortening is a different measurement and requires comparison with a reference value.

Abstract A011: Detection of disseminated tumor cells in advanced clear cell renal cell carcinoma through research autopsy

Background: The vast majority of cancer deaths can be attributed to tumor metastases. Disseminated tumor cells (DTCs) are thought to act as a reservoir of tumor clones which can lie dormant before causing overt metastases. Their presence has been shown to be a poor prognostic indicator in several tumor types. Despite their importance, the timing and source of DTCs is unclear across most solid cancers and even less is known about them in late-stage disease. The Posthumous Evaluation of the Advanced Cancer Environment (PEACE) post-mortem study enables extensive sampling of malignant lesions but also normal tissues, thereby allowing study of DTCs in patients with advanced cancer. Methods: We performed research autopsy sampling of macroscopically normal bone, lung and liver in 3 patients with advanced clear cell renal cell carcinoma (RCC). In addition, we performed bone marrow aspiration at autopsy from vertebral bodies and the ilium using an anterior approach. Mechanical disaggregation followed by collagenase digestion was used to generate single cell suspensions. Detection of tumor cells was carried out using antibodies against known tumor or epithelial markers carbonic anhydrase IX (CAIX). Epithelial cell adhesion molecule (EpCAM) was also used for bone marrow samples as native bone marrow cells do not express this marker. These sub-populations were then isolated using fluorescence activated cell sorting and DNA was extracted and amplified from single cells. Results: We performed and optimised collagenase-based digestion on all solid tissues collected. The percentage of viable cells generated varied significantly between subjects and tissues with bone marrow samples more viable than lung and liver. Rare and distinct populations of CAIX+ and EpCAM+ cells were detected in normal tissues between 0.5-2%. DNA amplification was successful on single cells isolated from normal lung and liver but not from bone tissue. Pilot shallow coverage whole genome sequencing revealed genomically aberrant cells ranging from single chromosome arm losses to widespread copy number aberrations. Conclusion: We demonstrate feasibility of sequencing single cells from autopsy study subjects. Rare populations of single cells with markers of clear cell RCC were detected and isolated both in normal tissues of patients with advanced disease. Genomic analyses of these cells will lead to insights into their relationship to the primary tumor and overt metastatic lesions.

Citation Format: Haixi Yan, Cristina Cotobal Martin, Christie English, Annelien Verfaillie, Jonas Demeulemeester, Andrew Rowan, Annika Fendler, Anne-Laure Cattin, Sucheta Mahapatra, Lewis Au, Scott Shepherd, Ben Shum, Charlotte Spencer, Zayd Tippu, Ula Mahadeva, Anna Green, Eleanor Carlyle, Cristina Naceur-Lombardelli, PEACE consortium, Mariam Jamal-Hanjani, Charles Swanton, Samra Turajlic, Peter Van Loo. Detection of disseminated tumor cells in advanced clear cell renal cell carcinoma through research autopsy [abstract]. In: Proceedings of the AACR Special Conference: Cancer Metastasis; 2022 Nov 14-17; Portland, OR. Philadelphia (PA): AACR; Cancer Res 2022;83(2 Suppl_2):Abstract nr A011.

Stabilized Radiation Pressure Acceleration and Neutron Generation in Ultrathin Deuterated Foils

Premature relativistic transparency of ultrathin, laser-irradiated targets is recognized as an obstacle to achieving a stable radiation pressure acceleration in the "light sail" (LS) mode. Experimental data, corroborated by 2D PIC simulations, show that a few-nm thick overcoat surface layer of high Z material significantly improves ion bunching at high energies during the acceleration. This is diagnosed by simultaneous ion and neutron spectroscopy following irradiation of deuterated plastic targets. In particular, copious and directional neutron production (significantly larger than for other in-target schemes) arises, under optimal parameters, as a signature of plasma layer integrity during the acceleration.

Stakeholder perspectives of a pilot multicomponent delirium prevention intervention for adult patients with advanced cancer in palliative care units: A behaviour change theory-based qualitative study

BACKGROUND

Theory-based and qualitative evaluations in pilot trials of complex clinical interventions help to understand quantitative results, as well as inform the feasibility and design of subsequent effectiveness and implementation trials.

AIM

To explore patient, family, clinician and volunteer ('stakeholder') perspectives of the feasibility and acceptability of a multicomponent non-pharmacological delirium prevention intervention for adult patients with advanced cancer in four Australian palliative care units that participated in a phase II trial, the 'PRESERVE pilot study'.

DESIGN

A trial-embedded qualitative study via semi-structured interviews and directed content analysis using Michie's Behaviour Change Wheel and the Theoretical Domains Framework.

SETTING/PARTICIPANTS

Thirty-nine people involved in the trial: nurses (n = 17), physicians (n = 6), patients (n = 6), family caregivers (n = 4), physiotherapists (n = 3), a social worker, a pastoral care worker and a volunteer.

RESULTS

Participants' perspectives aligned with the 'capability', 'opportunity' and 'motivation' domains of the applied frameworks. Of seven themes, three were around the alignment of the delirium prevention intervention with palliative care (intervention was considered routine care; intervention aligned with the compassionate and collaborative culture of palliative care; and differing views of palliative care priorities influenced perspectives of the intervention) and four were about study processes more directly related to adherence to the intervention (shared knowledge increased engagement with the intervention; impact of the intervention checklist on attention, delivery and documentation of the delirium prevention strategies; clinical roles and responsibilities; and addressing environmental barriers to delirium prevention).

CONCLUSION

This theory-informed qualitative study identified multiple influences on the delivery and documentation of a pilot multicomponent non-pharmacological delirium prevention intervention in four palliative care units. Findings inform future definitive studies of delirium prevention in palliative care.Australian New Zealand Clinical Trials Registry, ACTRN12617001070325; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=373168.

Experiences of female partners of prostate cancer survivors: A systematic review and thematic synthesis

The purpose of this systematic review and synthesis of studies reporting qualitative data was to understand the gendered experiences of female partners of prostate cancer survivors to inform psychosocial support for women. We searched Medline, PsycINFO, EMBASE, AMED, CINAHL, Cochrane Database of Systematic Reviews, and Sociological Abstracts for articles on 15 and 16 April 2019, and again on 30 November 2020. English language articles published in peer-reviewed journals were included if they reported solely on findings describing the perspectives of the female partners. Extracted data were analysed using line-by-line coding, organisation of codes into descriptive themes, and development of analytical themes. A theoretical framework was then selected to organise the relationships between issues that were found to be central to the experiences of female partners. Of 4839 articles screened, 14 met inclusion criteria, reporting 13 studies with a total sample of 359 female partners. Ussher and Sandoval's theory to describe the gendered positionings of cancer caregivers accommodated the thematic findings. The overarching theme reflected the substantive psychosocial impact of prostate cancer on female partners. Women's experiences were influenced by self-positioning (as part of a couple; provider of support to their male partner; resilient; and guided by faith and spirituality), being positioned by their partners' response (manager of male partner's psychological distress or strengthened by male partner's positive response) and by their broader contexts (family members and social networks; clinicians and the health system; and cultural values and customs). Findings highlight the need to avoid reductionist approaches to gender. Greater consideration of 'contextualised femininities', or conceptualising the influence of gender roles, relations, and identities within the wider life course contexts of female partners is required in the design and delivery of psychosocial support services.

Efficacy of tPBM on ADHD symptoms and Executive Function Deficits in Adults with high-functioning Autism Spectrum Disorder

Introduction

Executive function (EF) deficits are often associated with Autism Spectrum Disorder (ASD), even in the absence of Attention Deficit Hyperactivity Disorder (ADHD) diagnosis. To date, no approved medication treatments exist for EF deficits associated with ASD.

Objectives

To assess the efficacy of transcranial photobiomodulation (tPBM) on EF in adults with ASD.

Methods

Adults (18-59) with high-functioning (HF)-ASD received twice a week tPBM for 8 weeks in an open-label single group design. ASD and EF deficits were assessed by clinician-rated Clinical Global Impression Scale and patient-rated scales of Behavior Rating Inventory of Executive Function-Adult (BRIEF-A).

Results

Eleven participants were enrolled. Ten participants completed the study. Nine participants who completed the study had comorbid ADHD diagnosis. All 10 participants were included in efficacy analyses of EF deficits. Statistically significant improvements in executive function deficits were found in BRIEF-A total score and in subdomains of Inhibition, Emotional Control, Planning and Organization, Organization of Materials, Behavioral Regulation, Metacognitive Index and Global Executive Control. All participants were found to have mild to moderate improvement in their ADHD symptom severity per clinician rated CGIs. Statistically significant improvements in ADHD symptoms were noted in self-rated scales. No adverse events required changes in tPBM protocol.

Conclusions

tPBM is a safe and feasible treatment approach that has the potential to treat core features of ASD. Further research is necessary and warranted.

Disclosure

This work is funded by Alan and Lorraine Bressler Clinical and Research Program for Autism Spectrum Disorder and the MGH Pediatric Psychopharmacology Council Fund.

Abstract PR002: Advanced melanoma exhibits a diversity of evolutionary routes to lethality

Despite recent advances in the treatment of advanced melanoma using immune checkpoint inhibitors (ICI), 5-year overall survival remains suboptimal. A clear understanding of the potential evolutionary trajectories of melanoma is needed in order to advance treatment and prognostic options. Here we present the Posthumous Evaluation of Advanced Cancer Environment (PEACE) study of advanced melanoma, revealing a diversity of evolutionary pathways to lethality. This interim analysis of our 50-patient cohort comprises 14 ICI-treated patients with a mixture of phenotypic subtypes, including cutaneous, acral, mucosal and melanoma of unknown primary. The sampling regime encompasses a broad range of visceral metastases from various organ sites, with a total of 573 tumor samples (an average of 40 samples per patient). Our data span a variety of modalities, including exomic, transcriptomic, panel sequencing, single cell sequencing, FISH, and radiological data. Clonal phylogenies of patients were diverse in structure: some followed a linear evolutionary trajectory with little to no branching, whereas others followed a branched evolutionary pattern. We also observed various patterns of metastatic seeding, with both monoclonal and polyclonal cases of seeding. In addition, patients treated with chemotherapy showed higher subclonal mutational burden than those without. As with previous literature, we found extensive copy number alterations in these advanced melanomas. In contrast, however, our data also reveal patients with no incidence of WGD, with previous work finding this to be a ubiquitous feature of advanced melanoma. In cases of WGD, the majority of copy number alterations were losses rather than gains. In terms of treatment resistance, we observed loss of heterozygosity in key genes of the antigen presentation pathway (most notably B2M), and little signal of neoantigen loss via immunoediting, indicating that these tumors develop resistance to ICI regardless of neoantigen burden. A further question of interest was the determination of lesion-level factors influencing response to ICI treatment using radiological data. MYC amplification was significantly associated with non-responding lesions, whilst PBX1, a promoter of natural killer cells, was shown to be significantly amplified in responding lesions. Our single-cell data reveal a case of polyclonal seeding at the level of whole-genome doubling. This has implications for sample-level phylogenies that are inferred from copy-number status, indicating that intra-tumor heterogeneity at the level of copy number could confound these trees. We also find a potentially novel driver of melanoma, PHF3. This gene has previously been associated with UV DNA-damage response, however here it was found in a non-sun damaged melanoma to have a clonal, focal 7n copy number gain in an otherwise diploid cancer, with corresponding upregulation of expression. In summary, our study comprises an extensive intra-patient, multi-lesion analysis of advanced melanoma, with important implications in both technical and clinical settings.

Citation Format: Alexander Coulton, Irene Lobon, Lavinia Spain, Andrew Rowan, Desiree Shnidrig, Scott Shepherd, Ben Shum, Fiona Byrne, Lewis Au, Kim Edmonds, Ellie Carlyle, Alexandra Renn, Christina Messiou, Charlotte Spencer, Andreas M. Schmidt, Zayd Tippu, Aljosja Rogiers, Max Emmerich, Camille Gerard, Husayn Pallikonda, Cristina Naceur-Lombardelli, Floris Foijer, Hilda van den Bos, René Wardenaar, Diana Spierings, Kate Young, Lisa Pickering, Andrew Furness, Elaine Borg, Miriam Mitchison, David Moore, Mary Falzon, Ian Proctor, Ruby Stewart, Ula Mahadeva, Anna Green, James Larkin, Charles Swanton, Mariam Jamal-Hanjani, Kevin Litchfield, Samra Turajlic. Advanced melanoma exhibits a diversity of evolutionary routes to lethality [abstract]. In: Proceedings of the AACR Special Conference on the Evolutionary Dynamics in Carcinogenesis and Response to Therapy; 2022 Mar 14-17. Philadelphia (PA): AACR; Cancer Res 2022;82(10 Suppl):Abstract nr PR002.

Abstract A012: Advanced melanoma exhibits a diversity of evolutionary routes to lethality

This abstract is being presented as a short talk in the scientific program. A full abstract is available in the Proffered Abstracts section (PR002) of the Conference Proceedings.

Citation Format: Alexander Coulton, Irene Lobon, Lavinia Spain, Andrew Rowan, Desiree Shnidrig, Scott Shepherd, Ben Shum, Fiona Byrne, Lewis Au, Kim Edmonds, Ellie Carlyle, Alexandra Renn, Christina Messiou, Charlotte Spencer, Andreas M. Schmidt, Zayd Tippu, Aljosja Rogiers, Max Emmerich, Camille Gerard, Husayn Pallikonda, Cristina Naceur-Lombardelli, Floris Foijer, Hilda van den Bos, René Wardenaar, Diana Spierings, Kate Young, Lisa Pickering, Andrew Furness, Elaine Borg, Miriam Mitchison, David Moore, Mary Falzon, Ian Proctor, Ruby Stewart, Ula Mahadeva, Anna Green, James Larkin, Charles Swanton, Mariam Jamal-Hanjani, Kevin Litchfield, Samra Turajlic. Advanced melanoma exhibits a diversity of evolutionary routes to lethality [abstract]. In: Proceedings of the AACR Special Conference on the Evolutionary Dynamics in Carcinogenesis and Response to Therapy; 2022 Mar 14-17. Philadelphia (PA): AACR; Cancer Res 2022;82(10 Suppl):Abstract nr A012.

Absolute calibration of Fujifilm BAS-TR image plate response to laser driven protons up to 40 MeV

Image plates (IPs) are a popular detector in the field of laser driven ion acceleration, owing to their high dynamic range and reusability. An absolute calibration of these detectors to laser-driven protons in the routinely produced tens of MeV energy range is, therefore, essential. In this paper, the response of Fujifilm BAS-TR IPs to 1-40 MeV protons is calibrated by employing the detectors in high resolution Thomson parabola spectrometers in conjunction with a CR-39 nuclear track detector to determine absolute proton numbers. While CR-39 was placed in front of the image plate for lower energy protons, it was placed behind the image plate for energies above 10 MeV using suitable metal filters sandwiched between the image plate and CR-39 to select specific energies. The measured response agrees well with previously reported calibrations as well as standard models of IP response, providing, for the first time, an absolute calibration over a large range of proton energies of relevance to current experiments.

Disrupted Peyer's Patch Microanatomy in COVID-19 Including Germinal Centre Atrophy Independent of Local Virus

Confirmed SARS-coronavirus-2 infection with gastrointestinal symptoms and changes in microbiota associated with coronavirus disease 2019 (COVID-19) severity have been previously reported, but the disease impact on the architecture and cellularity of ileal Peyer's patches (PP) remains unknown. Here we analysed post-mortem tissues from throughout the gastrointestinal (GI) tract of patients who died with COVID-19. When virus was detected by PCR in the GI tract, immunohistochemistry identified virus in epithelium and lamina propria macrophages, but not in lymphoid tissues. Immunohistochemistry and imaging mass cytometry (IMC) analysis of ileal PP revealed depletion of germinal centres (GC), disruption of B cell/T cell zonation and decreased potential B and T cell interaction and lower nuclear density in COVID-19 patients. This occurred independent of the local viral levels. The changes in PP demonstrate that the ability to mount an intestinal immune response is compromised in severe COVID-19, which could contribute to observed dysbiosis.

Designing Supportive e-Interventions for Partners of Men With Prostate Cancer Using Female Partners’ Experiences: Qualitative Exploration Study

Background

Partners of men living with prostate cancer (PCa) can experience a variety of unmet needs that are largely unaddressed by health care professionals. There is limited evidence to suggest which approach may be most effective in supporting partners’ unmet needs and further research is required to determine how to provide support to caregivers and how technology solutions can be designed.

Objective

This study aims to explore the experience of partners of men living with PCa and their perceptions of the potential role of information technology in supporting their needs.

Methods

A qualitative descriptive methodology using focus groups and phone interviews was used. Purposive sampling was used to recruit people attending a national conference supported by a national PCa organization. Interview guides were adapted from an existing evidence-based smartphone app for caregivers of people with colorectal cancer. Sessions were audio recorded and transcribed verbatim. A coding framework was developed, and transcripts were coded line by line into the framework. Codes within the framework were grouped into descriptive categories that were then developed into analytical themes.

Results

A total of 17 female partners participated in the study, with an average age of 64 (SD 8.5) years. The following two main themes emerged: In the first theme, that is, How technology can be shaped to support female partners of prostate cancer survivors, the content and design of the smartphone app was discussed in addressing female partners’ needs. The following four subthemes were developed: getting support from social networks and resources, the lack of relevant information, demystifying future care expectations during and following a PCa diagnosis, and delivering the smartphone app—to whom and from whom. In the second theme, that is, The benefits and barriers of technology, the suitability of smartphone apps as a supportive modality for female partners was described. This included three subthemes: the smartphone app as an appropriate modality for supporting female partners, the future anticipated benefits of using the smartphone app, and concerns for storing and accessing information on the internet.

Conclusions

A smartphone app may be a suitable modality for providing information and peer support to female partners of men living with PCa. There is a need to provide peer support for female partners in future interventions to ensure that female partners’ intimacy and daily practical needs are met.

The Scottish Brain Health Service Model: Rationale and Scientific Basis for a National Care Pathway of Brain Health Services in Scotland

In order to address the oft-cited societal, economic, and health and social care impacts of neurodegenerative diseases, such as Alzheimer's disease, we must move decisively from reactive to proactive clinical practice and to embed evidence-based brain health education throughout society. Most disease processes can be at least partially prevented, slowed, or reversed. We have long neglected to intervene in neurodegenerative disease processes, largely due to a misconception that their predominant symptom - cognitive decline - is a normal, age-related process, but also due to a lack of multi-disciplinary collaboration. We now understand that there are modifiable risk factors for neurodegenerative diseases, that successful management of common comorbidities (such as diabetes and hypertension) can reduce the incidence of neurodegenerative disease, and that disease processes begin (and, crucially, can be detected, reduced, and delayed, prevented, or treated) decades earlier in life than had previously been appreciated. Brain Health Scotland, established by Scottish Government and working in partnership with Alzheimer Scotland, propose far-reaching public health and clinical practice approaches to reduce neurodegenerative disease incidence. Focusing here on Brain Health Scotland's clinical offerings, we present the Scottish Model for Brain Health Services. To our knowledge, the Scottish Model for Brain Health, built on foundations of personalised risk profiling, targeted risk reduction and prevention, early disease detection, equity of access, and harnessing comprehensive data to assist in clinical decision-making, marks the first example of a nationwide approach to overhauling clinical, societal, and political approaches to the prevention, assessment, and treatment of neurodegenerative disease.

A broad-scale spatial analysis of the environmental benefits of fertiliser closed periods implemented under the Nitrates Directive in Europe

Nutrient pollution from agriculture has been an ongoing challenge for decades, contributing to numerous negative environmental impacts. In the European Union policies have been developed to address nutrient pollution, including Nitrate Action Programmes under Council Directive 91/676/EEC. Although Member States report on progress on implementation, there have been few studies that explore how measures have been implemented; the environmental implications of any differences; and how they vary spatially on a European scale. This study aims to address this gap with respect to fertiliser closed periods (1155 different closed periods across 69 Nitrate Action Programmes). This included the development of an approach that can be applied using readily available spatial data. Each closed period was scored for its coverage of risk periods for losses of nitrate; organic material; nitrous oxide and ammonia. Closed periods were then matched to relevant combinations of spatial data for each environmental zone and fertiliser type. The scores for each combination were used to create maps and calculate spatial statistics. The results show that in addition to nitrate, closed periods also reduce the risk of organic material run-off, emissions of nitrous oxide and to a lesser extent ammonia. However, risk reduction is spatially variable across all the impacts and the scope for synergy is also variable (e.g. nitrate loss does not always correlate with nitrous oxide or ammonia risk reduction). Regions in the Atlantic, Lustanian and some areas within the Mediterranean zones appear to provide the greatest combined risk reduction, with other zones, especially in eastern Europe, having a lower combined risk reduction (due to a combination of different risk periods coupled with lower coverage of individual risks). The spatial analysis within this study is relatively simple; is based on a snapshot of closed periods during 2019-2020; and only explores one measure. However, it does provide some useful data and insights that could support policy development in the future. This includes scope for Member States and regions to learn from others where greater coverage of risk periods has been achieved; and highlighting how a more holistic perspective can be taken to the environmental management of nutrients. As we strive towards developing sustainable production systems, farmers and policy makers need to take a more integrated approach to incorporate additional environmental objectives; which increases the complexity of the challenge. Consequently, the demand for pragmatic approaches that take a more holistic approach is likely to increase in the future.

Evaluating the potential for respiratory metagenomics to improve treatment of secondary infection and detection of nosocomial transmission on expanded COVID-19 intensive care units

BACKGROUND

Clinical metagenomics (CMg) has the potential to be translated from a research tool into routine service to improve antimicrobial treatment and infection control decisions. The SARS-CoV-2 pandemic provides added impetus to realise these benefits, given the increased risk of secondary infection and nosocomial transmission of multi-drug-resistant (MDR) pathogens linked with the expansion of critical care capacity.

METHODS

CMg using nanopore sequencing was evaluated in a proof-of-concept study on 43 respiratory samples from 34 intubated patients across seven intensive care units (ICUs) over a 9-week period during the first COVID-19 pandemic wave.

RESULTS

An 8-h CMg workflow was 92% sensitive (95% CI, 75-99%) and 82% specific (95% CI, 57-96%) for bacterial identification based on culture-positive and culture-negative samples, respectively. CMg sequencing reported the presence or absence of β-lactam-resistant genes carried by Enterobacterales that would modify the initial guideline-recommended antibiotics in every case. CMg was also 100% concordant with quantitative PCR for detecting Aspergillus fumigatus from 4 positive and 39 negative samples. Molecular typing using 24-h sequencing data identified an MDR-K. pneumoniae ST307 outbreak involving 4 patients and an MDR-C. striatum outbreak involving 14 patients across three ICUs.

CONCLUSION

CMg testing provides accurate pathogen detection and antibiotic resistance prediction in a same-day laboratory workflow, with assembled genomes available the next day for genomic surveillance. The provision of this technology in a service setting could fundamentally change the multi-disciplinary team approach to managing ICU infections. The potential to improve the initial targeted treatment and rapidly detect unsuspected outbreaks of MDR-pathogens justifies further expedited clinical assessment of CMg.

ReIMAGINE: a prostate cancer research consortium with added value through its patient and public involvement and engagement

BACKGROUND

ReIMAGINE aims to improve the current prostate specific antigen (PSA)/biopsy risk stratification for prostate cancer (PCa) and develop a new image-based method (with biomarkers) for diagnosing high/low risk PCa in men. ReIMAGINE's varied patient and public involvement (PPI) and engagement (PE) strategy maximises the impact of its scientific output by informing and shaping the different stages of research.

AIMS

Through including the voice of patients and the public, the ReIMAGINE Consortium aims to translate these different perspectives into the design and implementation process. This will improve the overall quality of the research by: reflecting the needs and priorities of patients and the public, ensuring methods and procedures are feasible and appropriate ensuring information is relevant and accessible to those being recruited to the study identifying dissemination channels relevant to patients/the public and developing outputs that are accessible to a lay audience With support from our patient/user groups, the ReIMAGINE Consortium aims to improve our ability to derive prognostic information and allocate men to the most appropriate and effective therapies, using a novel image-based risk stratification with investigation of non-imaging biomarkers.

FINDINGS

We have been working with patients and the public from initiation of the project to ensure that the research is relevant to men and their families. Our PPI Sub-Committee, led by a PCa patient, has been involved in our dissemination strategy, outreach activities, and study design recommendations. For example, the sub-committee have developed a variety of informative videos relevant and accessible to those being recruited, and organised multiple online research engagement events that are accessible to a lay audience. As quoted by one of the study participants, "the more we present the benefits and opportunities to patients and the public, the more research commitment we obtain, and the sooner critical clinical questions such as PCa diagnostics will be addressed".

Determinants of anti-PD-1 response and resistance in clear cell renal cell carcinoma

ADAPTeR is a prospective, phase II study of nivolumab (anti-PD-1) in 15 treatment-naive patients (115 multiregion tumor samples) with metastatic clear cell renal cell carcinoma (ccRCC) aiming to understand the mechanism underpinning therapeutic response. Genomic analyses show no correlation between tumor molecular features and response, whereas ccRCC-specific human endogenous retrovirus expression indirectly correlates with clinical response. T cell receptor (TCR) analysis reveals a significantly higher number of expanded TCR clones pre-treatment in responders suggesting pre-existing immunity. Maintenance of highly similar clusters of TCRs post-treatment predict response, suggesting ongoing antigen engagement and survival of families of T cells likely recognizing the same antigens. In responders, nivolumab-bound CD8+ T cells are expanded and express GZMK/B. Our data suggest nivolumab drives both maintenance and replacement of previously expanded T cell clones, but only maintenance correlates with response. We hypothesize that maintenance and boosting of a pre-existing response is a key element of anti-PD-1 mode of action.