Citations

Radiotherapy (RT) of colorectal cancer (CRC) can prime adaptive immunity against tumor-associated antigen (TAA)–expressing CRC cells systemically. However, abscopal tumor remissions are extremely rare, and the postirradiation immune escape mechanisms in CRC remain elusive. Here, we found that irradiated CRC cells used ATR-mediated DNA repair signaling pathway to up-regulate both CD47 and PD-L1, which through engagement of SIRPα and PD-1, respectively, prevented phagocytosis by antigen-presenting cells and thereby limited TAA cross-presentation and innate immune activation. This postirradiation CD47 and PD-L1 up-regulation was observed across various human solid tumor cells. Concordantly, rectal cancer patients with poor responses to neoadjuvant RT exhibited significantly elevated postirradiation CD47 levels. The combination of RT, anti-SIRPα, and anti–PD-1 reversed adaptive immune resistance and drove efficient TAA cross-presentation, resulting in robust TAA-specific CD8 T cell priming, functional activation of T effectors, and increased T cell clonality and clonal diversity. We observed significantly higher complete response rates to RT/anti-SIRPα/anti–PD-1 in both irradiated and abscopal tumors and prolonged survival in three distinct murine CRC models, including a cecal orthotopic model. The efficacy of triple combination therapy was STING dependent as knockout animals lost most benefit of adding anti-SIRPα and anti–PD-1 to RT. Despite activation across the myeloid stroma, the enhanced dendritic cell function accounts for most improvements in CD8 T cell priming. These data suggest ATR-mediated CD47 and PD-L1 up-regulation as a key mechanism restraining radiation-induced immune priming. RT combined with SIRPα and PD-1 blockade promotes robust antitumor immune priming, leading to systemic tumor regressions.

e24016 Background: Recent studies of patients (pts) with gastrointestinal stromal tumor (GIST) have included an older patient population. The majority of these have focused on treatment, but little is known regarding the optimal duration of surveillance following surgery for localized disease. Methods: We conducted a retrospective study of pts age 70 years (yrs) and above (≥) at diagnosis (dx), who underwent surgery for their localized GIST. Charts were reviewed of GIST diagnosed between 1992 to 2016, to allow at least 5 yrs for surveillance, if performed. Demographics were analyzed and pts were risk stratified using modified NIH criteria. Results: We identified 42 pts with a median age of 74 yrs (70 to 89 yrs) at dx. The majority of pts were male (31, 74%) and non-Hispanic White (37, 88%). Most pts had gastric GIST (25, 60%). The median resected tumor was 47 mm (range 6 to 190). Thirty-nine of 42 pts had margin status documented R0 resection. The median overall survival for all pts was 7.9 yrs (1.1 to 17.7), with median recurrence free survival 5.6 yrs (1.1 to 13.7). Only 4 of 16 (25%) pts died from GIST recurrence, and all were detected under 5 yrs from surgery. Fourteen of 34 pts (41%) who survived over 5 yrs from resection had extended surveillance imaging. Demographics and risk stratification are shown in Table. None of the 16 low risk pts developed recurrence, including 6 (38%) whose surveillance imaging continued beyond 5 yrs. Among 7 intermediate risk pts, only 1 pt (14%) extended surveillance imaging beyond 5 yrs. Two intermediate risk pts (29%) developed recurrence and were symptomatic at dx. One intermediate risk pt died from GIST metastasis within 1 yr from surgery. Seven of 19 (37%) high risk pts had surveillance imaging beyond 5 yrs following surgical resection. Seven high risk pts (37%) developed recurrence within median 5.6 yrs (1.6 to 13.7) from surgery; five of these were detected on imaging. In the high risk pts with recurrence, 5 had received adjuvant imatinib and 2 declined any systemic therapy. Three pts (16%) in the high risk cohort died from GIST. Conclusions: In this cohort of pts age ≥ 70 yrs with resected GIST, the majority of pts were symptomatic at relapse. Older pts who undergo surgery for low risk GIST may not require extended surveillance. Fit, older pts with high risk GIST may benefit from extended surveillance imaging, even if they received adjuvant imatinib.[Table: see text]

8057 Background: Following autologous hematopoietic stem cell transplant (auto HCT), maintenance therapies improve survival, reduce relapse risk in multiple myeloma (MM), and are the de facto standard-of-care. However, clinical trials have shown an increased risk of second primary malignancies (SPM) with maintenance therapy, including second hematological malignancies (SHM). We examined data from the Center for International Blood and Marrow Transplant Research (CIBMTR) registry to evaluate the impact of SPM on progression-free (PFS) and overall survival (OS) and the utilization of allogeneic HCT in patients with therapy-related myeloid neoplasms (t-MN). Methods: Adult patients (pts) with MM who underwent first auto HCT in the United States with a melphalan conditioning regimen from 2011-2018 and subsequently received maintenance therapy were included (N=3948). The primary endpoint of interest was the impact of SPM and SHM on OS. Multivariate analytic (MVA) modelling was applied, accounting for competing risks while integrating significant covariates to determine the impact of SPM on PFS and OS. Finally, we studied the utilization and survival following allogeneic HCT for SHM. Results: Baseline characteristics were similar between the two groups. Maintenance regimens used were lenalidomide (2836, 72%), bortezomib (370,9 %) or lenalidomide + bortezomib (372, 9%) based combinations. At a median follow up of 37 months, 175 (5%) pts developed SPM, including 112 (64%) solid 36 (21%) myeloid, and 27 (15%) lymphoid cancers. In MVA, the development of SPM and SHM was associated with an inferior PFS (HR 2.62, P<0.001 and HR 5.01, P<0.001, respectively) and OS (HR 3.85, P<0.001 and 8.13, P<0.001, respectively). The two commonest causes of death were MM (42%) and SPM (30%) for those developing SPM. Similarly, MM (53%) and SHM (18%) were the two commonest causes of death for those developing SHM. Nine (14%,5 t-MDS and 4 t-AML) of 63 patients with SHM underwent an allogeneic HCT. Patients undergoing allogeneic HCT were more likely to have Karnofsky score ≥90 (100% vs. 50%, P=0.02) compared to those who did not. One year survival from allo SCT was 66.7% (CI 34.6-92%). Conclusions: The three-year cumulative incidence of SPM was 3.3 (2.6-4)% in this large contemporaneous CIBMTR cohort. Disease relapse remains the primary cause of death in MM patients who develop SPM or SHM. Given the median OS for MM is now > 10 years, longer follow-up is needed to assess the SPM and SHM risks with maintenance therapy post-auto HCT.

Abstract Objective Using a US Food and Drug Administration (FDA) emergency use authorization (EUA) reverse transcription polymerase chain reaction (RT-PCR) method, we examined the analytic performance accuracy of saliva specimens as compared to nasopharyngeal (NP) specimens in symptomatic patients. Correlation between test results and symptoms was also evaluated. Methods Over a 5-week period in 2020, 89 matched saliva and nasopharyngeal swabs were collected from individuals exhibiting symptoms consistent with SARS-CoV-2. Specimens were tested with an FDA EUA-approved RT-PCR method, and performance characteristics were compared. Results The concordance rate between saliva and nasopharyngeal testing was 93.26%. The mean cycle threshold value of saliva when compared to the NP specimen was 3.56 cycles higher. As compared to NP swab, saliva testing demonstrates acceptable agreement but lower sensitivity. Conclusion When compared to a reference method using NP swabs, the use of saliva testing proved to be a reliable method. Self-collected saliva testing for SARS-CoV-2 allows for a viable option when trained staff or collection materials are in short supply.

Background The American Association for the Surgery of Trauma (AAST) has developed a grading system for emergency general surgery (EGS) conditions. We sought to validate the AAST EGS grades for patients undergoing urgent/emergent colorectal resection. Methods Patients enrolled in the “Eastern Association for the Surgery of Trauma Multicenter Colorectal Resection in EGS—to anastomose or not to anastomose” study undergoing urgent/emergent surgery for obstruction, ischemia, or diverticulitis were included. Baseline demographics, comorbidity severity as defined by Charlson comorbidity index (CCI), procedure type, and AAST grade were prospectively collected. Outcomes included length of stay (LOS) in-hospital mortality, and surgical complications (superficial/deep/organ-space surgical site infection, anastomotic leak, stoma complication, fascial dehiscence, and need for further intervention). Multivariable logistic regression models were used to describe outcomes and risk factors for surgical complication or mortality. Results There were 367 patients, with a mean (± SD) age of 62 ± 15 years. 39% were women. The median interquartile range (IQR) CCI was 4 (2-6). Overall, the pathologies encompassed the following AAST EGS grades: I (17, 5%), II (54, 15%), III (115, 31%), IV (95, 26%), and V (86, 23%). Management included laparoscopic (24, 7%), open (319, 87%), and laparoscopy converted to laparotomy (24, 6%). Higher AAST grade was associated with laparotomy ( P = .01). The median LOS was 13 days (8-22). At least 1 surgical complication occurred in 33% of patients and the mortality rate was 14%. Development of at least 1 surgical complication, need for unplanned intervention, mortality, and increased LOS were associated with increasing AAST severity grade. On multivariable analysis, factors predictive of in-hospital mortality included AAST organ grade, CCI, and preoperative vasopressor use (odds ratio (OR) 1.9, 1.6, 3.1, respectively). The American Association for the Surgery of Trauma emergency general surgery grade was also associated with the development of at least 1 surgical complication (OR 2.5), while CCI, preoperative vasopressor use, respiratory failure, and pneumoperitoneum were not. Conclusion The American Association for the Surgery of Trauma emergency general surgery grading systems display construct validity for mortality and surgical complications after urgent/emergent colorectal resection. These results support incorporation of AAST EGS grades for quality benchmarking and surgical outcomes research.

Abstract Funding Source: Institutional funds at Mayo Clinic. Background: While alopecia is a common and distressing acute side effect of chemotherapy, chronic hair thinning is also reported by some survivors during endocrine therapy. The purpose of the current study was to evaluate real world experiences of late/long-term alopecia among breast cancer survivors. Methods: Breast cancer survivors participating in the ongoing prospective Mayo Clinic Breast Disease Registry (MCBDR) were mailed a survey six years after diagnosis, between June and November 2020. Respondents were asked to report how bothered they are by hair thinning and hair loss over the last year on a scale from 0 “not at all” to 4 “extremely”. They were also asked whether they used any hair thickening or regrowth products. Results: 552/899 survivors responded (response rate 61%); 403 survivors’ responses were available for analysis. Respondents’ median age was 66 years, and median time since diagnosis was 78 months. Seventy patients (17%) were diagnosed with stage 0 breast cancer, 195 (48%) were diagnosed with stage 1 cancer, 104 (26%) with stage 2, 25 (6%) with stage 3; 6 (1%) had been diagnosed with metastatic or recurrent disease at the time of this survey. 139 (34%) patients had received chemotherapy. Of the patients who received chemotherapy, 82 (59%) had received doxorubicin and cyclophosphamide, 41 (29%) received docetaxel and cyclophosphamide, 77 (55%) received paclitaxel, and 27 (19%) received carboplatin. 258 (64%) received endocrine therapy. Of these patients who received endocrine therapy, 131 (51%) received Tamoxifen and 186 (72%) received aromatase inhibitors. 309 survivors (77%) were 55 years or older. 189 (47%) of all patients reported that they were bothered by chronic hair loss, and 225 (56%) reported that they were bothered by hair thinning; 71 (18%) reported use of thickening/regrowth products. There did not appear to be differences in chronic hair loss or thinning by receipt of chemotherapy: 64 patients (46%) who received chemotherapy reported hair loss and 79 (56%) reported hair thinning, compared with 123 patients (46%) who did not receive chemotherapy and reported hair loss and 142 (54%) who reported hair thinning. Hair thinning or loss did not appear to differ based upon age (Table 1). Symptoms did not appear to be more common amongst current or previous endocrine therapy recipients, with 113 (44%) of that subset bothered by hair loss and 128 (50%) by hair thinning. Conclusion: Hair loss and thinning are frequently reported as bothersome symptoms by long-term breast cancer survivors. Future investigations into treatments for chronic hair thinning during and after cancer therapy are needed. Table 1.&lt; 5555+Bothered by hair loss (n)%Bothered by hair thinning (n)%Bothered by hair loss (n)%Bothered by hair thinning (n)%Not at all5761%4649%15751%13142%Slightly1920%2426%8728%9731%Moderately77%910%3110%4113%BOTHERED BY HAIR LOSS (N)%BOTHERED BY HAIR THINNING (N)%BOTHERED BY HAIR LOSS (N)%BOTHERED BY HAIR THINNING (N)%Quite a bit77%1112%227%268%Extremely44%33%93%103%Missing00%11%31%41% Citation Format: Elizabeth Cathcart-Rake, Charles L Loprinzi, Janet E Olson, Fergus Couch, Brittany Dulmage, Maryam Lustberg, Nicole Larson, Kathryn J Ruddy. Alopecia among breast cancer survivors [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P4-10-17.

Abstract Background: Eyebrow and eyelash loss are widely recognized as consequences of some chemotherapies, but prevalence and predictors are understudied. The purpose of this study was to evaluate real world experiences of eyebrow and eyelash loss during treatment for breast cancer. Methods: Breast cancer survivors participating in the ongoing prospective Mayo Clinic Breast Disease Registry (MCBDR) were mailed a survey one year after diagnosis. Respondents were asked to recall their severity of eyebrow and eyelash loss since diagnosis, measured from “no loss” to “a little loss” to “a lot of loss” to “complete loss”. Results: 524 participants were mailed a survey including these questions between May 2020 and November 2020; the median time from diagnosis to survey completion was 12 months (range 6 months). Of the 265 participants whose responses were available for analysis (median age 60.8 years), 88 (33%) had received chemotherapy, including 39 (44%) who received doxorubicin and cyclophosphamide, 16 (18%) who received docetaxel and cyclophosphamide, 56 (64%) who received paclitaxel, and 11 (13%) who received carboplatin. 173 (65%) had received endocrine therapy: 56 (32%) of patients who received endocrine therapy received tamoxifen, and 115 (66%) received aromatase inhibitors. 124 (47%) reported at least a little eyebrow loss, and 22 (8%) reported complete loss. Forty-seven percent reported at least a little eyelash loss, and 27 (10%) reported complete loss (Table 1). In the subgroup of 88 patients who received chemotherapy, the rates of at least a little eyebrow and eyelash loss were 50% and 55%, respectively, and rates of complete loss were 8% and 9%. Rates of eyebrow and eyelash loss did not appear to differ significantly by age. Conclusion: Eyebrow and eyelash loss are frequently reported during breast cancer-directed therapy. Future investigations into the incidence and treatment of this side effect are needed. Table 1.&lt;55 years old55+ years oldEyebrow Loss (N)%Eyelash Loss (N)%Eyebrow Loss (N)%Eyelash Loss (N)%No Loss4551%4753%9655%9353%A Little Loss2629%2225%3922%3922%A lot of loss1011%1112%2715%2514%Complete Loss89%910%148%1810%Funding Source: Breast Cancer Research Foundation (CLL) Clinic Citation Format: Elizabeth Cathcart-Rake, Charles L Loprinzi, Fergus Couch, Janet Olson, Brittany Dulmage, Maryam Lustberg, Nicole Larson, Kathryn J Ruddy. Eyebrow/eyelash loss among survivors [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P4-10-11.