One CD4+TCR and One CD8+TCR Targeting Autochthonous Neoantigens Are Essential and Sufficient for Tumor Eradication

PURPOSE

To achieve eradication of solid tumors, we examined how many neoantigens need to be targeted with how many T-cell receptors (TCR) by which type of T cells.

EXPERIMENTAL DESIGN

Unmanipulated, naturally expressed (autochthonous) neoantigens were targeted with adoptively transferred TCR-engineered autologous T cells (TCR-therapy). TCR-therapy used CD8+ T-cell subsets engineered with TCRs isolated from CD8+ T cells (CD8+TCR-therapy), CD4+ T-cell subsets engineered with TCRs isolated from CD4+ T cells (CD4+TCR-therapy), or combinations of both. The targeted tumors were established for at least 3 weeks and derived from primary autochthonous cancer cell cultures, resembling natural solid tumors and their heterogeneity as found in humans.

RESULTS

Relapse was common with CD8+TCR-therapy even when targeting multiple different autochthonous neoantigens on heterogeneous solid tumors. CD8+TCR-therapy was only effective against homogenous tumors artificially derived from a cancer cell clone. In contrast, a combination of CD8+TCR-therapy with CD4+TCR-therapy, each targeting one neoantigen, eradicated large and established solid tumors of natural heterogeneity. CD4+TCR-therapy targeted a mutant neoantigen on tumor stroma while direct cancer cell recognition by CD8+TCR-therapy was essential for cure. In vitro data were consistent with elimination of cancer cells requiring a four-cell cluster composed of TCR-engineered CD4+ and CD8+ T cells together with antigen-presenting cells and cancer cells.

CONCLUSIONS

Two cancer-specific TCRs can be essential and sufficient to eradicate heterogeneous solid tumors expressing unmanipulated, autochthonous targets. We demonstrate that simplifications to adoptive TCR-therapy are possible without compromising efficacy.

Single CAR-T cell treatment controls disseminated ovarian cancer in a syngeneic mouse model

BACKGROUND

Treatment of some blood cancers with T cells that express a chimeric antigen receptor (CAR) against CD19 have shown remarkable results. In contrast, CAR-T cell efficacy against solid tumors has been difficult to achieve.

METHODS

To examine the potential of CAR-T cell treatments against ovarian cancers, we used the mouse ovarian cancer cell line ID8 in an intraperitoneal model that exhibits disseminated solid tumors in female C57BL/6J mice. The CAR contained a single-chain Fv from antibody 237 which recognizes a Tn-glycopeptide-antigen expressed by ID8 due to aberrant O-linked glycosylation in the absence of the transferase-dependent chaperone Cosmc. The efficacy of four Tn-dependent CARs with varying affinity to Tn antigen, and each containing CD28/CD3ζ cytoplasmic domains, were compared in vitro and in vivo in this study.

RESULTS

In line with many observations about the impact of aberrant O-linked glycosylation, the ID8Cosmc knock-out (ID8Cosmc-KO) exhibited more rapid tumor progression compared with wild-type ID8. Despite the enhanced tumor growth in vivo, 237 CAR and a mutant with 30-fold higher affinity, but not CARs with lower affinity, controlled advanced ID8Cosmc-KO tumors. Tumor regression could be achieved with a single intravenous dose of the CARs, but intraperitoneal administration was even more effective. The CAR-T cells persisted over a period of months, allowing CAR-treated mice to delay tumor growth in a re-challenge setting. The most effective CARs exhibited the highest affinity for antigen. Antitumor effects observed in vivo were associated with increased numbers of T cells and macrophages, and higher levels of cleaved caspase-3, in the tumor microenvironment. Notably, the least therapeutically effective CAR mediated tonic signaling leading to antigen-independent cytokine expression and it had higher levels of the immunosuppressive cytokine interleukin10.

CONCLUSION

The findings support the development of affinity-optimized CAR-T cells as a potential treatment for established ovarian cancer, with the most effective CARs mediating a distinct pattern of inflammatory cytokine release in vitro. Importantly, the most potent Tn-dependent CAR-T cells showed no evidence of toxicity in tumor-bearing mice in a syngeneic, immunocompetent system.

Criteria to make animal studies more relevant to treating human cancer

Certain aspects of experimental tumor models in mice most accurately reflect the biology and immunology of cancer in patients. A survey of experimental cancer immunotherapy papers published in 2020 shows most do not achieve cancer shrinkage although treatment is initiated at an early time point after cancer cell injection, which does not reflect cancer immunotherapy in patients. Even then, few current experimental approaches eradicate the injected malignant cells, most only delay outgrowth. The value of targeting mutation-encoded tumor-specific antigens becomes increasingly evident while problems of finding normal gene-encoded tumor-associated antigens as safe, effective targets persist. It might be time to refocus on realistic experimental settings and truly cancer-specific targets. These antigens are associated with the least risk of side effects.

The relationship between emotional well-being and understanding of prognosis in patients with acute myeloid leukemia (AML)

PURPOSE

Adults with acute myeloid leukemia (AML) face considerable distress and often have a poor prognosis. However, little is known about these patients' perceptions of prognosis and how this relates to emotional well-being (EWB).

METHODS

We conducted a prospective, observational study of 50 adult patients with AML initiating chemotherapy, and surveyed them longitudinally for 6 months about their prognosis, treatment goals, quality of life, and EWB (by FACT-G). We derived a prognostic estimate for each patient based on data from published trials summarized in National Comprehensive Care Network Guidelines. We used descriptive statistics and longitudinal modeling to test the hypothesis that more accurate prognostic awareness is associated with worse EWB.

RESULTS

Most patients (n = 43; 86%) had an objectively poor prognosis attributable to relapsed disease, complex karyotype, or FLT3 mutation. Yet, 74% of patients reported expecting a 50% or greater chance of cure. Patients with a poor prognosis more often had discordant prognostic estimates, compared to those with favorable risk AML (OR = 7.25, 95% CI 1.21, 43.37). Patient-reported prognostic estimates did not vary significantly over time. At baseline, patients who better understood their prognosis had worse EWB and overall quality-of-life scores (EWB 12 vs. 19.5; p = 0.01; FACT-G 65 vs. 75.5; p = 0.01).

CONCLUSION

Patients with AML overestimate their prognosis, and awareness of a poor prognosis is associated with worse emotional well-being. Efforts are needed to improve patients' understanding of their prognosis, and to provide more psychosocial support and attention to well-being as part of high-quality leukemia care.

Cooperation of genes in HPV16 E6/E7-dependent cervicovaginal carcinogenesis trackable by endoscopy and independent of exogenous estrogens or carcinogens

Human papillomavirus (HPV) infection is necessary but insufficient for progression of epithelial cells from dysplasia to carcinoma-in situ (CIS) to invasive cancer. The combination of mutant cellular and viral oncogenes that regulate progression of cervical cancer (CC) remains unclear. Using combinations of HPV16 E6/E7 (E+), mutant Kras (mKras) (K+) and/or loss of Pten (P-/-), we generated autochthonous models of CC without exogenous estrogen, carcinogen or promoters. Furthermore, intravaginal instillation of adenoCre virus enabled focal activation of the oncogenes/inactivation of the tumor suppressor gene. In P+/+ mice, E6/E7 alone (P+/+E+K-) failed to cause premalignant changes, while mKras alone (P+/+E-K+) caused persistent mucosal abnormalities in about one-third of mice, but no cancers. To develop cancer, P+/+ mice needed both E6/E7 and mKras expression. Longitudinal endoscopies of P+/+E+K+ mice predicted carcinoma development by detection of mucosal lesions, found on an average of 23 weeks prior to death, unlike longitudinal quantitative PCRs of vaginal lavage samples from the same mice. Endoscopy revealed that individual mice differed widely in the time required for mucosal lesions to appear after adenoCre and in the time required for these lesions to progress to cancer. These cancers developed in the transition zone that extends, unlike in women, from the murine cervix to the distal vagina. The P-/-E+K+ genotype led to precipitous cancer development within a few weeks and E6/E7-independent cancer development occurred in the P-/-E-K+ genotype. In the P-/-E+K- genotype, mice only developed CIS. Thus, distinct combinations of viral and cellular oncogenes are involved in distinct steps in cervical carcinogenesis.

Differences between patients with cardiovascular disease and cancer referred for palliative care

Our analysis from a national registry shows that compared to cancer, cardiovascular disease patients referred to palliative care are a decade older, have worse functional status and clinician-estimated prognosis. Both groups have very high symptom burden, with cardiovascular disease patients experiencing more dyspnea while pain, nausea, and fatigue are more common in cancer.

Characteristics of Advance Care Planning in Patients With Cancer Referred to Palliative Care

PURPOSE

Advance care planning (ACP) is a process in which patients share their values, goals, and preferences regarding future medical care. ACP can improve care quality, yet may be challenging to address for patients with cancer. We sought to characterize key components of ACP in patients with cancer as compared with patients with noncancer serious illness referred to palliative care (PC).

METHODS

We performed a retrospective cross-sectional analysis of initial outpatient PC visits from the Quality Data Collection Tool for PC database from 2015 to 2019. Quality Data Collection Tool is a web-based point-of-care specialty PC registry to track quality metrics.

RESULTS

We analyzed 1,604 patients with cancer and 1,094 patients without cancer: 44% of patients were female, 87% were White, and 98% were non-Hispanic. The average age was 72.2 years (standard deviation [SD] 15.4). Patients with cancer were on average younger than patients without cancer (66.5 [SD: 13.9] v 80.5 [SD: 13.8]) and had a higher Palliative Performance Scale (PPS) (59.5 [SD: 22.4] v 33.4 [SD: 25.1]). In our unadjusted comparison, patients with cancer were less likely to be DNR/DNI (37% v 53%; P < .0001) and less likely to have an advance directive (53% v 73%; < .0001); rates of healthcare proxy identification were similar (92.8% v 94.5%; P = .10). These differences did not persist when we accounted for age, race, sex, and PPS, with age being the primary explanatory factor.

CONCLUSION

Despite having serious illness meriting PC referral, many patients with cancer in our study lacked advance directives. This highlights both the important role of oncologists in facilitating ACP and the utility of PC playing a complementary role.

An analysis of missing items in real-world electronic patient reported outcomes data: implications for clinical care

PURPOSE

Utilization of electronic patient-reported outcomes (ePROs) in the clinic can improve quality of life and prolong survival in cancer care. However, there remain unanswered questions regarding trends in missing data and the potential effect on real-time patient care.

METHODS

This study utilized a prospectively collected dataset of ePROs from oncology clinics that administered the Patient Care Monitor 2.0 (PCM), a validated symptoms survey assessing 78 items for men, and 86 for women. We tabulated the frequency of missing items, by item and domain (emotional, functional and physical symptom-related), and examined these by age, gender, education, race and marital status.

RESULTS

Within 20,986 encounters, there were responses to at least 1 PCM item from 6933 unique patients. The highest frequency of missing answers occurred for: "attend a paid job" (10.7%), "reduced sexual enjoyment" (3.8%), and "run" (3.7%). By domain, 12.3% of functional, 8.4% of physical symptom-related, and 1.6% of emotional constructs contained at least one missing item. For functional and physical symptom-related items, missingness was most common in patients >60 years old.

CONCLUSION

The frequency of missingness was highest for functional items, like attending a paid job, suggesting that some respondents (e.g., retirees without a paid job) skipped questions that were less applicable to them. More universal issues for cancer patients, such as emotional well-being, had much lower frequencies of missingness. This suggests differential item completion that warrants further study to understand the inherent drivers. Identifying causes of missingness could improve the clinical utility of ePROs and highlight opportunities to personalize care.

Abstract 3238: Engineering chimeric antigen receptors for adoptive T cell therapy of cancers that express the Tn antigen

Chimeric antigen receptors (CARs) have shown remarkable promise in treating hematological malignancies, especially those expressing CD19 antigen. On the other hand, identification and efficacy of CARs against antigens in solid cancers has remained a significant challenge. Defects in glycosylation in solid cancers are common, and can result in formation of cell surface-expressed neoantigens that are aberrantly glycosylated. Here, we focused on antigens that result from defects in O-linked glycosylation, leading to formation of unique antigens that possess an N-acetyl-galactosamine linked to a serine or threonine residue on a surface-expressed protein (also called Tn antigen), instead of extended glycosylation patterns. 237 is a mouse monoclonal antibody that was generated by a mouse immunized with cells of a spontaneous murine cancer, and that binds to a Tn-antigen linked to the mouse protein, OTS8. Previously, we showed that a CAR generated from the 237 single chain variable fragment (scFv) recognized, with low affinity, the human cell line Jurkat. More recently, we demonstrated that the 237 CAR could eradicate established Jurkat leukemia in a mouse model. Here, we used structure-guided directed evolution to engineer the binding site of 237 to bind to multiple Tn linked antigens, including MUC1, with higher affinity. CARs containing these engineered scFv variants recognized a panel of glycosylation-defective mouse and human cancer cell lines more effectively than the wild-type 237 CAR, with no activity toward cell lines lacking these defects. Cancer cell lines lacking MUC1 were also effectively recognized by the engineered variants, indicating their broadened specificity toward multiple Tn-linked antigens. Consistent with this finding, the CAR variants also demonstrated greater sensitivity toward several Tn-linked human peptides. To extend these studies, we are currently developing additional mouse models to study the efficacy of the engineered 237 CARs in the control of solid tumors. In summary, we developed efficient chimeric antigen receptors that recognize multiple, cancer-associated Tn linked antigens, based on a single antibody scaffold. We believe that their specific recognition of Tn antigen, together with broadened peptide-backbone reactivity, holds promise for cancer-specific recognition yet minimal antigen escape against tumors with defects in O-linked glycosylation, because cancer-specific Tn-linked epitopes on several independent proteins can be simultaneously targeted.

Citation Format: Preeti Sharma, Venkata VVR Marada, Monika Kizerwetter, Claire P. Schane, Yanran He, Steven P. Wolf, Karin Schreiber, Edward J. Roy, Henrik Clausen, Hans Schreiber, David M. Kranz. Engineering chimeric antigen receptors for adoptive T cell therapy of cancers that express the Tn antigen [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 3238.

Automated cell cluster analysis provides insight into multi-cell-type interactions between immune cells and their targets

Understanding interactions between immune cells and their targets is an important step on the path to fully characterizing the immune system, and in doing so, learning how it combats disease. Many studies of these interactions have a narrow focus, often looking only at a binary result of whether or not a specific treatment was successful or only focusing on the interactions between two individual cells. Therefore, in an effort to more comprehensively study multicellular interactions among immune cells and their targets, we used in vitro longitudinal time-lapse imaging and developed an automated cell cluster analysis tool, or macro, to investigate the formation of cell clusters. In particular, we investigated the behavior of cancer-specific CD8⁺ and CD4⁺ T cells on how they interact around their targets: cancer cells and antigen-presenting cells. The macro that we established allowed us to examine these large-scale clustering behaviors taking place between those four cell types. Thus, we were able to distinguish directed immune cell clustering from random cell movement. Furthermore, this macro can be generalized to be applicable to systems consisting of any number of differently labeled species and can be used to track clustering behaviors and compare them to randomized simulations.

Prevalence and Predictors of Burnout Among Hospice and Palliative Care Clinicians in the U.S

CONTEXT

Many clinical disciplines report high rates of burnout, which leads to low quality of care. Palliative care clinicians routinely manage patients with significant suffering, aiming to improve quality of life. As a major role of palliative care clinicians involves educating patients and caregivers regarding identifying priorities and balancing stress, we wondered how clinician self-management of burnout matches against the emotionally exhaustive nature of the work.

OBJECTIVES

We sought to understand the prevalence and predictors of burnout using a discipline-wide survey.

METHODS

We asked American Academy of Hospice and Palliative Medicine clinician members to complete an electronic survey querying demographic factors, job responsibilities, and the Maslach Burnout Inventory. We performed univariate and multivariable regression analyses to identify predictors of high rates of burnout.

RESULTS

We received 1357 responses (response rate 30%). Overall, we observed a burnout rate of 38.7%, with higher rates reported by nonphysician clinicians. Most burnout stemmed from emotional exhaustion, with depersonalization comprising a minor portion. Factors associated with higher odds of burnout include nonphysician clinical roles, working in smaller organizations, working longer hours, being younger than 50 years of age, and working weekends. We did not observe different rates between palliative care clinicians and hospice clinicians. Higher rated self-management activities to mitigate burnout include participating in interpersonal relationships and taking vacations.

CONCLUSION

Burnout is a major issue facing the palliative care clinician workforce. Strategies at the discipline-wide and individual levels are needed to sustain the delivery of responsive, available, high-quality palliative care for all patients with serious illness.

Impact of TCR Diversity on the Development of Transplanted or Chemically Induced Tumors

Burnet postulated that the diversity of T-cell receptors (TCR) allows T cells to protect against the development of cancers that display antigens with a similar, seemingly endless diversity. To test this hypothesis, we developed a strategy in which a single breeding pair of mice gives rise to four groups of sibling mice. Three of the four groups had a similar number of CD8⁺ T cells, but TCR diversity was either broad, significantly reduced, or absent when expressing only one type of TCR. The fourth group had no T cells. All mice shared the same housing, and, therefore, their microbial environment was similar. Only slight differences in the intestinal flora were observed under these conditions. An undisturbed broad TCR repertoire was required for the rejection of inoculated cancers displaying the natural antigenic heterogeneity of primary tumors, whereas even one type of TCR was sufficient to protect against artificial cancers stably expressing cognate antigens. The three groups of mice with limited or no TCR repertoire showed an increased risk of developing primary tumors after chemical induction. However, the risk of early death or morbidity in these cohorts of mice was significantly higher than in mice with a diverse TCR repertoire, and it remains unknown whether mice with reduced TCR diversity, who died early without cancer, would have developed tumors with higher, lower, or equal probability after induction. Together, TCR diversity seems crucial to overcome the natural genetic instability of cancers and their antigenic heterogeneity, which impacts the design of cellular therapies.

Multiple cancer-specific antigens are targeted by a chimeric antigen receptor on a single cancer cell

Human cancer cells were eradicated by adoptive transfer of T cells transduced with a chimeric antigen receptor (CAR) made from an antibody (237Ab) that is highly specific for the murine Tn-glycosylated podoplanin (Tn-PDPN). The objectives were to determine the specificity of these CAR-transduced T (CART) cells and the mechanism for the absence of relapse. We show that although the 237Ab bound only to cell lines expressing murine Tn-PDPN, the 237Ab-derived 237CART cells lysed multiple different human and murine cancers not predicted by the 237Ab binding. Nevertheless, the 237CART cell reactivities remained cancer specific because all recognitions were dependent on the Tn glycosylation that resulted from COSMC mutations that were not present in normal tissues. While Tn was required for the recognition by 237CART, Tn alone was not sufficient for 237CART cell activation. Activation of 237CART cells required peptide backbone recognition but tolerated substitutions of up to 5 of the 7 amino acid residues in the motif recognized by 237Ab. Together, these findings demonstrate what we believe is a new principle whereby simultaneous recognition of multiple independent Tn-glycopeptide antigens on a cancer cell makes tumor escape due to antigen loss unlikely.

Integration of Electronic Patient-Reported Outcomes Into Routine Cancer Care: An Analysis of Factors Affecting Data Completeness

PURPOSE

Routinely collected patient-reported outcomes (PROs) could provide invaluable data to a patient-centered learning health system but are often highly missing in clinical trials. We analyzed our experience with PROs to understand patterns of missing data using electronic collection as part of routine clinical care.

METHODS

This is an analysis of a prospectively collected observational database of electronic PROs captured as part of routine clinical care in four different outpatient oncology clinics at an academic referral center.

RESULTS

More than 24,000 clinical encounters from 7,655 unique patients are included. Data were collected via an electronic tablet-based survey instrument (Patient Care Monitor, version 2.0), at the time of clinical care, as part of routine care processes. Missing instruments (ie, no items completed) were submitted for 6.8% of clinical encounters, and 15.8% of encounters had missing items. Nearly 90% of all encounters involved < 10% missing items. In multivariable analyses, younger age, private health insurance, being seen in the breast oncology clinic, less time spent on the instrument, and longitudinal care were significantly associated with less missingness.

CONCLUSION

Embedding collection of electronic PRO data into routine clinical care yielded low rates of missing data in this real-world, prospectively collected database. In contrast to clinical trial experience, missingness improve with longitudinal care. This approach may be a solution to minimizing missingness of PROs in research or clinical care settings in support of learning health care systems.

Characteristics and Trends Among Patients With Cardiovascular Disease Referred to Palliative Care

IMPORTANCE

Use of palliative care (PC) for patients with cardiovascular disease (CVD) has increased recently. However, it is unknown if patients are receiving earlier referrals to PC.

OBJECTIVE

To assess characteristics and trends of patients with CVD referred to PC.

DESIGN, SETTING, AND PARTICIPANTS

Cohort study in which analysis of data from the multicenter Quality Data Collection Tool for Palliative Care registry from January 2, 2015, through December 29, 2017, included patients with CVD 18 years or older referred to initial PC consultation who had a documented palliative performance score (PPS) .

EXPOSURES

Patients with CVD who presented for an initial PC visit.

MAIN OUTCOMES AND MEASURES

The primary outcome was PPS. Secondary outcomes included symptoms and end-of-life documentation.

RESULTS

Among 1801 patients (mean [SD] age, 77.7 [13.7] years) from 16 sites in the analysis, 875 (48.6%) were women and 1339 (74.3%) were white. A low PPS score (0%-30%), consistent with bedbound status, was recorded for 521 patients (28.9%), with no change through time. The most common moderate to severe symptoms were poor well-being, tiredness, anorexia, and dyspnea. Year of encounter was associated with improved symptoms of pain (odds ratio, 1.25; 95% CI, 1.05-1.50) and with constipation (odds ratio, 1.32; 95% CI, 1.03-1.69). No change through time was noted in other symptoms or end-of-life documentation. Although the proportion of referrals from general medicine increased from 43.2% (167 of 387) in 2015 to 52.9% (410 of 775) in 2017, the proportion of referrals from cardiologists decreased from 16.5% (64 of 387) in 2015 to 10.5% (81 of 775) in 2017. The proportion of patients referred to PC who were black decreased from 11.9% (46 of 387) in 2015 to 6.3% (49 of 775) in 2017. While 69.5% of all patients with CVD (1252 of 1801) had a primary diagnosis of heart failure, the proportion of non-heart failure CVD diagnoses, such as coronary artery disease and valvular heart disease, increased from 25.6% (99 of 387) in 2015 to 30.1% (233 of 775) in 2017.

CONCLUSIONS AND RELEVANCE

Patients with CVD demonstrated significant symptom burden, and there was no evidence in the registry of change in the PPSs of patients with CVD referred to PC through time. Cardiologists provided comparatively fewer referrals to PC for patients with CVD, and this proportion decreased through time. The proportion of racial and ethnic minorities referred to PC was small and decreased through time. These findings reinforce the need for cardiologists to be more engaged with PC and consider referring appropriate patients with CVD sooner.

Pruritus in patients with solid tumors: an overlooked supportive care need

PURPOSE

Pruritus is a common symptom in cutaneous malignancies, but its impact on patients with solid tumors is unclear. We explored the impact and management of pruritus in patients with solid tumors, using patient-reported outcomes (PRO) data from a real-world registry.

METHODS

From 2006 to 2011, patients seen in the Duke Cancer Institute reported their symptoms via the Patient Care Monitor v2.0, a validated PRO tool that includes a 0-10-point question about pruritus severity. From > 25,000 encounters, 203 patients reported severe pruritus (> 6/10) on at least one visit and 506 total visits were abstracted where patients reported either moderate or severe pruritus (> 3/10). From this cohort, we abstracted demographics, diagnosis, stage, cancer therapy, anti-pruritic therapy, and clinicians' responses.

RESULTS

Mean age was 59.8 (SD 13.3), 134 (66%) were female, 125 (62%) were Caucasian, and 65 (32%) were African American. Breast cancer was the most common tumor (36.5%), followed by lung cancer (23.2%). Mean pruritus severity score was 6.8 (SD 1.8) for patients on chemotherapy, 6.9 (SD 1.8) for patients on targeted therapy alone or in combination, and 7.1(SD 1.8) for patients off treatment. Overall, 67% of patients reported at least two episodes of moderate-severe pruritus (mean # of visits 4.2 (SD 2.7)). Despite frequent report of severe and persistent pruritus, this was mentioned in just 28% of clinician notes and an intervention was recommended/prescribed in only 7% of visits.

CONCLUSIONS

Pruritus is an under-addressed symptom in patients with solid tumors. Additional research is needed to understand the burden of pruritus in affected populations.

Abstract 3587: TCR-transduced T cells targeting a truncal mutation caused by a nsSNV destroy large solid tumors despite intratumoral genetic heterogeneity

Most if not all cancers have individually specific, so-called unique antigens that we discovered in 1995 to be caused by somatic tumor-specific, non-synonymous single nucleotide substitutions, now usually referred to as nsSNVs, and we showed already then that adoptive transfer of nsSNV-specific T cells has specific anti-cancer effects (Monach P. et al. Immunity 2:45-59, 1995). With the rapid advances in sequencing technologies, these antigens, now generally also called "mutant neoantigens", have been discovered on all primary cancers examined in the past decade, human or experimental, (unless a cancer was the result of artificial genetic engineering). The number of somatic mutations, mostly nsSNVs, differs widely between cancers and tumor types. Importantly however, even patients bearing cancers with a low mutational burden usually have 12 different HLA alleles to possibly present a given mutant peptide as antigen to T cells. Since most mutations in cancers are individually patient-specific, a truly personalized, i.e., patient-specific therapy is required. Encouragement for investing into developing such an approach comes from our recent studies in which we show that a single type of T cell receptor (TCR) targeting a single cancer-specific point mutation, i.e. nsSNV-encoded mutant peptide, can eradicate large solid tumors when the mutation-specific TCR is transduced into peripheral T cells and adoptively transferred (Leisegang, M. et al. Clin. Cancer Res. 22: 2734-43 2016). Here, we examine the relative influence of mutant antigen expression level, intratumoral heterogeneity as well as competence of the transferred mutation-specific T cells on escape of the cancer from therapy using adoptive transfer of T cells specific for a given mutation. The importance and mechanisms of bystander killing in cancer escape will also be discussed and the importance of cross-presentation of the neoantigen by the tumor stroma will be examined. Together, our current studies are consistent with the notion that adoptive transfer of T cells transduced with TCRs recognizing nsSNV-encoded peptides may provide a novel and potentially extremely powerful completely cancer-specific approach in patients with established solid tumors. In addition, the concept should be applicable to most cancer patients, if efforts are made to truly individualize cancer therapy. This requires focus on identifying the set of patient-specific nsSNV and the set of 12 patient-specific MHCI and MHCII that are available to potentially present the mutant peptides of a given patient's cancer as targets for tumor destruction. Supported by NIH grants R01-CA22677 and R01-CA37156, the Cancer Research Foundation, a collaborative research grant by the Berlin Institute of Health and the Einstein-Stiftung Berlin.

Citation Format: Matthias Leisegang, Karin Schreiber, Steven P. Wolf, Vasiliki Anastosopolou, Kimberley Borutta, PohYin Yew, Kazuma Kiyotani, Yusuke Nakamura, Hans Schreiber. TCR-transduced T cells targeting a truncal mutation caused by a nsSNV destroy large solid tumors despite intratumoral genetic heterogeneity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3587.

The impact of remission status on patients' experiences with acute myeloid leukemia (AML): an exploratory analysis of longitudinal patient-reported outcomes data

PURPOSE

Shared decision-making in acute myeloid leukemia (AML) requires understanding patients' longitudinal experiences of illness, but little is known about the impact of remission status on patient-reported outcomes (PROs). We aimed to explore the association between remission status and PROs 6-12 months following induction chemotherapy.

METHODS

Forty-two patients completed three validated instruments characterizing symptom burden (Patient Care Monitor v2.0), distress (NCCN Distress Thermometer), and QOL (FACT-Leu), as part of a longitudinal observational study. We used regression models to explore the relationship between remission status and PROs, and explore differences by initial disease type (de novo versus secondary/relapsed AML).

RESULTS

Those with secondary or relapsed AML at study onset had marked impairments in all measures compared to de novo AML patients. After 6 months, their mean distress score was 4.8 (> 4.0 warrants intervention), they reported a mean of 14.1 moderate/severe symptoms and had a mean QOL score of 113.6, compared to 1.0, 1.7, and 155.2, respectively, for those with de novo AML (p < .0001). Similarly, patients in relapse had a mean distress score of 5.3, a mean of 12.8 moderate/severe symptoms, and a mean QOL score of 113.4, compared to 1.8, 5.7, and 143.8, respectively, among those in remission (p < .005). These patterns persisted after adjusting for baseline differences (p < .0001).

CONCLUSION

Remission is associated with markedly better patient well-being in AML. Patients with secondary or relapsed AML face more severe symptom burden, distress, and QOL issues after induction. Interventions are needed to improve AML patients' experiences of illness.

Comparing the Palliative Care Needs of Patients With Hematologic and Solid Malignancies

CONTEXT

Hematologic cancer patients use palliative care services less frequently than their solid tumor counterparts. Prior work suggests that these patients have a sizable symptom burden, but comparisons between hematologic and solid tumor patients near the end of life are limited.

OBJECTIVES

To compare unmet symptom needs in a cohort of hematologic and solid tumor patients referred to specialty palliative care services.

METHODS

Using a novel data registry of initial palliative care encounters, we performed a cross-sectional analysis of cancer patients receiving care across 17 sites within the Global Palliative Care Quality Alliance. We compared clinically-significant symptoms (rated as four or greater in severity) between hematologic and solid tumor patients and performed multivariate logistic regression analyses examining the relationship between symptom burden and tumor type.

RESULTS

We identified 1235 cancer patients, 108 of which had hematologic malignancies. Pain, dyspnea, nausea, and anorexia burden were as high among patients with hematologic as those with solid malignancies. Blood cancer patients had higher rates of clinically-significant tiredness (51% vs. 42%; P = 0.03) than solid tumor patients. Finally, blood cancer patients had greater odds of being tired (odds ratio 2.19; CI 1.22-3.91) and drowsy (odds ratio 1.81; CI 1.07-3.07) than solid tumor patients independent of age, gender, race, and performance status.

CONCLUSIONS

Hematologic and solid tumor patients have significant symptom burden at time of referral to palliative care services. Blood cancer patients may have unique concerns warranting targeted attention, including substantial drowsiness and tiredness. Our findings suggest a need to optimize palliative care usage in the hematologic cancer population.

Performance of Consultative Palliative Care Model in Achieving Quality Metrics in the ICU

CONTEXT

Quality metrics for intensive care unit (ICU)-based palliative care have been proposed, but it is unknown how consultative palliative care can contribute to performance on these measures.

OBJECTIVES

Assess adherence to proposed quality metrics of ICU-based palliative care by palliative care specialists.

METHODS

Surrogates for 9/14 patient-level quality metrics were assessed in all patients who received an initial palliative care specialist consult while in an ICU from 10/26/2012 to 1/16/2015 in the Global Palliative Care Quality Alliance, a nationwide palliative care quality registry.

RESULTS

Two hundred fifty-four patients received an initial palliative care consultation in an ICU setting. Mean (SD) age was 67.5 (17.3) years, 52% were female. The most common reasons for consultation were symptom management (33%) and end-of-life transition (24%). Adherence to ICU quality metrics for palliative care was variable: clinicians documented presence or absence of advance directives in 36% of encounters, assessed pain in 52.0%, dyspnea in 50.8%, spiritual support in 62%, and reported an intervention for pain in 100% of patients with documented moderate to severe intensity pain.

CONCLUSION

Palliative care consultations in an ICU setting are characterized by variable adherence to candidate ICU palliative care quality metrics. Although symptom management was the most common reason for palliative care consultation, consultants infrequently documented symptom assessments. Palliative care consultants performed better in offering spiritual support and managing documented symptoms. These results highlight specific competencies of consultative palliative care that should be complimented by ICU teams to ensure high-quality comprehensive care for the critically ill.

Anticholinergic Drug Burden in Noncancer Versus Cancer Patients Near the End of Life

CONTEXT

Anticholinergic drugs can cause several side effects, impairing cognition and quality of life (QOL). Cancer patients are often exposed to increasing cumulative anticholinergic load (ACL) as they approach death, but this burden has not been examined in patients with nonmalignant diseases.

OBJECTIVES

To determine ACL and its impact in noncancer versus cancer palliative care patients.

METHODS

We performed a secondary analysis of 244 subjects enrolled in a randomized controlled trial. ACL was quantified with the Anticholinergic Drug Scale. We used multivariable regression to calculate the effect of ACL on key outcomes, including drowsiness, fatigue, and QOL. Patients were stratified by diagnosis, and drugs were grouped as symptom management (SM) or disease management (DM).

RESULTS

Overall, ACL in cancer and noncancer patients was not significantly different (2.6 vs. 2.4; P = 0.23). SM drugs caused greater anticholinergic exposure than DM drugs in both cancer and noncancer patients (2.3 vs. 0.5, and 1.5 vs. 1.3, respectively; both P < 0.05); however, DM drugs exposed noncancer patients to relatively more ACL than cancer patients (1.2 vs. 0.6, P < 0.0001). ACL was associated with worse fatigue (odds ratio, 1.08; CI, 1.002-1.17) and worse QOL (odds ratio, 0.89; CI, 0.80-0.98).

CONCLUSIONS

ACL is associated with worse fatigue and QOL and may not differ significantly between cancer and noncancer patients nearing end of life. SM drugs are more responsible for ACL in cancer and noncancer patients, although DM drugs contribute significantly to ACL in the latter group. We recommend more attention to reducing anticholinergic use in all patients with life-limiting illness.

A practical measurement of thoracic sarcopenia: correlation with clinical parameters and outcomes in advanced lung cancer

Sarcopenia, the loss of skeletal muscle mass, is common in chronic disease, and has been hypothesised to contribute to fatigue and breathlessness [1, 2]. The research gold standard for assessing sarcopenia relies on whole-body, cross-sectional imaging, an impractical approach in routine care [3]. A more practical alternative measures lumbar skeletal muscle density at L3 using computed tomography (CT) normalised for height, termed the skeletal muscle index (SMI) [4]. While evidence suggests that reduced lumbar SMI correlates with adverse clinical outcomes, such as mortality in lung or colorectal cancers [5], little research has explored how this measure of sarcopenia relates to breathlessness or exercise tolerance.

Thoracic sarcopenia can feasibly be measured from routine CT scans but does not correlate to patient-centred outcomeshttp://ow.ly/102UkQ

Prevalence and Predictors of Burnout Among Hospice and Palliative Care Clinicians in the U.S

CONTEXT

Many clinical disciplines report high rates of burnout, which lead to low quality of care. Palliative care clinicians routinely manage patients with significant suffering, aiming to improve quality of life. As a major role of palliative care clinicians involves educating patients and caregivers regarding identifying priorities and balancing stress, we wondered how clinician self-management of burnout matches against the emotionally exhaustive nature of the work.

OBJECTIVES

We sought to understand the prevalence and predictors of burnout using a discipline-wide survey.

METHODS

We asked American Academy of Hospice and Palliative Medicine clinician members to complete an electronic survey querying demographic factors, job responsibilities, and the Maslach Burnout Inventory. We performed univariate and multivariate regression analyses to identify predictors of high rates of burnout.

RESULTS

We received 1357 responses (response rate 30%). Overall, we observed a burnout rate of 62%, with higher rates reported by nonphysician clinicians. Most burnout stemmed from emotional exhaustion, with depersonalization comprising a minor portion. Factors associated with higher rates of burnout include working in smaller organizations, working longer hours, being younger than 50 years, and working weekends. We did not observe different rates between palliative care clinicians and hospice clinicians. Higher rated self-management activities to mitigate burnout include participating in interpersonal relationships and taking vacations.

CONCLUSIONS

Burnout is a major issue facing the palliative care clinician workforce. Strategies at the discipline-wide and individual levels are needed to sustain the delivery of responsive, available, high-quality palliative care for all patients with serious illness.

Designing Colorectal Cancer Screening Decision Support: A Cognitive Engineering Enterprise

Adoption of clinical decision support has been limited. Important barriers include an emphasis on algorithmic approaches to decision support that do not align well with clinical work flow and human decision strategies, and the expense and challenge of developing, implementing, and refining decision support features in existing electronic health records (EHRs). We applied decision-centered design to create a modular software application to support physicians in managing and tracking colorectal cancer screening. Using decision-centered design facilitates a thorough understanding of cognitive support requirements from an end user perspective as a foundation for design. In this project, we used an iterative design process, including ethnographic observation and cognitive task analysis, to move from an initial design concept to a working modular software application called the Screening & Surveillance App. The beta version is tailored to work with the Veterans Health Administration's EHR Computerized Patient Record System (CPRS). Primary care providers using the beta version Screening & Surveillance App more accurately answered questions about patients and found relevant information more quickly compared to those using CPRS alone. Primary care providers also reported reduced mental effort and rated the Screening & Surveillance App positively for usability.

Unmet Needs of African Americans and Whites at the Time of Palliative Care Consultation

CONTEXT

Differences among patient populations that present to consultative palliative care are not known. Such an appreciation would inform health-care delivery tailored to unique populations.

OBJECTIVES

We aimed to compare characteristics and palliative care needs of African Americans (AAs) and whites during initial palliative care consultation.

METHODS

We analyzed patient-reported, clinician-entered clinical encounter data from a large, multisite community-based, nonhospice palliative care collaborative. We included first specialty palliative care consultations from January 1, 2014, to July 2, 2015, across 15 sites within the Global Palliative Care Quality Alliance registry. Demographics, disease, performance status, advance care planning, and symptom prevalence/severity were compared.

RESULTS

Of 775 patients, 12.9% (N = 100) were AA. African Americans were younger (63 vs 75.4 years, P < .0001). A larger proportion of AAs had a diagnosis of cancer (45.0% vs 36.3%, P = .09) and in the hospital (71% vs 61.8%, P = .07). African Americans were more likely to have a Palliative Performance Score of 0 to 30 (35.6% vs 23.7%, P = .049). Around 50% in both racial groups were full code; slightly more than 40% had an advance directive. Nearly two-thirds in both racial groups reported 3 or more symptoms of any severity; one-third reported 3 or more moderate or severe symptoms. A larger proportion of Africans than whites reported pain of any severity (66.0% vs 56.1%, P = .06).

CONCLUSION

All patients present to palliative care consultations with significant symptom and advance care planning needs. Further research is needed to identify how to deliver palliative care: earlier, in noncancer conditions, and improve pain management in AA populations.

There is a mismatch between the medicare benefit package and the preferences of patients with cancer and their caregivers

PURPOSE

To identify insured services that are most important to Medicare beneficiaries with cancer and their family caregivers when coverage is limited.

METHODS

A total of 440 participants (patients, n = 246; caregivers, n = 194) were enrolled onto the CHAT (Choosing Health Plans All Together) study from August 2010 to March 2013. The exercise elicited preferences about what benefits Medicare should cover for patients with cancer in their last 6 months of life. Facilitated sessions lasted 2.5 hours, included 8 to 10 participants, and focused on choices about Medicare health benefits within the context of a resource-constrained environment.

RESULTS

Six of 15 benefit categories were selected by > 80% of participants: cancer care, prescription drugs, primary care, home care, palliative care, and nursing home coverage. Only 12% of participants chose the maximum level of cancer benefits, a level of care commonly financed in the Medicare program. Between 40% and 50% of participants chose benefits not currently covered by Medicare: unrestricted cash, concurrent palliative care, and home-based long-term care. Nearly one in five participants picked some level of each of these three benefit categories and allocated on average 30% of their resources toward them.

CONCLUSION

The mismatch between covered benefits and participant preferences shows that addressing quality of life and the financial burden of care is a priority for a substantial subset of patients with cancer in the Medicare program. Patient and caregiver preferences can be elicited, and the choices they express could suggest potential for Medicare benefit package reform and flexibility.

A decision exercise to engage cancer patients and families in deliberation about Medicare coverage for advanced cancer care

Background

Concerns about unsustainable costs in the US Medicare program loom as the number of retirees increase and experiences serious and costly illnesses like cancer. Engagement of stakeholders, particularly cancer patients and their families, in prioritizing insured services offers a valuable strategy for informing Medicare coverage policy. We designed and evaluated a decision exercise that allowed cancer patients and family members to choose Medicare benefits for advanced cancer patients.

Methods

The decision tool, Choosing Health plans All Together (CHAT) was modified to select services for advanced cancer patients. Patients with a cancer history (N = 246) and their family members (N = 194) from North Carolina participated in 70 CHAT sessions. Variables including participants’ socio-demographic characteristics, health status, assessments of the exercise and results of group benefit selections were collected. Routine descriptive statistics summarized participant characteristics and Fisher’s exact test compared group differences. Qualitative analysis of group discussions were used to ascertain reasons for or against selecting benefits.

Results

Patients and family members (N = 440) participated in 70 CHAT exercises. Many groups opted for such services as palliative care, nursing facilities, and services not currently covered by the Medicare program. In choosing among four levels of cancer treatment coverage, no groups chose basic coverage, 27 groups (39%) selected intermediate coverage, 39 groups (56%) selected high coverage, and 4 groups (6%) chose the most comprehensive cancer coverage. Reasons for or against benefit selection included fairness, necessity, need for prioritizing, personal experience, attention to family needs, holistic health outlook, preference for comfort, freedom of choice, and beliefs about the proper role of government. Participants found the exercise very easy (59%) or fairly easy (39%) to understand and very informative (66%) or fairly informative (31%). The majority agreed that the CHAT exercise led to fair decisions about priorities for coverage by which they could abide.

Conclusions

It is possible to involve cancer patients and families in explicit discussions of their priorities for affordable advanced cancer care through the use of decision tools designed for this purpose. A key question is whether such a conversation is possible on a broader, national level.