Citations

Radiation-induced brain injury (RIBI) is a debilitating sequela after radiotherapy to treat head and neck cancer, and 20 to 30% of patients with RIBI fail to respond to or have contraindications to the first-line treatments of bevacizumab and corticosteroids. Here, we reported a Simon’s minmax two-stage, single-arm, phase 2 clinical trial (NCT03208413) to assess the efficacy of thalidomide in patients with RIBI who were unresponsive to or had contraindications to bevacizumab and corticosteroid therapies. The trial met its primary endpoint, with 27 of 58 patients enrolled showing ≥25% reduction in the volume of cerebral edema on fluid-attenuated inversion recovery–magnetic resonance imaging (FLAIR-MRI) after treatment (overall response rate, 46.6%; 95% CI, 33.3 to 60.1%). Twenty-five (43.1%) patients demonstrated a clinical improvement based on the Late Effects Normal Tissues–Subjective, Objective, Management, Analytic (LENT/SOMA) scale, and 36 (62.1%) experienced cognitive improvement based on the Montreal Cognitive Assessment (MoCA) scores. In a mouse model of RIBI, thalidomide restored the blood-brain barrier and cerebral perfusion, which were attributed to the functional rescue of pericytes secondary to elevation of platelet-derived growth factor receptor β (PDGFRβ) expression by thalidomide. Our data thus demonstrate the therapeutic potential of thalidomide for the treatment of radiation-induced cerebral vasculature impairment.

Importance Metastatic colorectal cancer (mCRC) with deficient DNA mismatch repair (dMMR) shows frequent and durable responses to programmed cell death 1 blockade. While most of these tumors are sporadic and observed in older patients, first-line pembrolizumab data are limited to findings from the KEYNOTE-177 trial (A Phase III Study of Pembrolizumab [MK-3475] vs Chemotherapy in Microsatellite Instability-High [MSI-H] or Mismatch Repair Deficient [dMMR] Stage IV Colorectal Carcinoma). Objective To investigate outcome with first-line pembrolizumab monotherapy in mostly older patients with dMMR mCRC at a multisite clinical practice. Design, Setting, and Participants This cohort study included consecutive patients with dMMR mCRC who received pembrolizumab monotherapy between April 1, 2015, and January 1, 2022, at Mayo Clinic sites and the Mayo Clinic Health System. Patients were identified from review of electronic health records at the sites, which included the evaluation of digitized radiologic imaging studies. Intervention Patients with dMMR mCRC received first-line pembrolizumab, 200 mg, every 3 weeks. Main Outcomes and Measures The primary study end point was progression-free survival (PFS), which was analyzed using the Kaplan-Meier method and a multivariable stepwise Cox proportional hazards regression model. Clinicopathological features, including metastatic site and molecular data ( BRAF V600E and KRAS ), were also analyzed along with tumor response rate, which was determined using Response Evaluation Criteria in Solid Tumors, version 1.1. Results The study cohort included 41 patients (median [IQR] age at treatment initiation, 81 [76-86] years; 29 females [71%]) with dMMR mCRC. Of these patients, 30 (79%) had the BRAF V600E variant and 32 (80%) were classified as having sporadic tumors. Median (range) follow-up was 23 (3-89) months. Median (IQR) number of treatment cycles was 9 (4-20). Overall response rate was 49% (20 of 41 patients), including 13 patients (32%) with complete responses and 7 (17%) with partial responses. Median (IQR) PFS was 21 (95% CI, 6-39) months. Liver as a site of metastasis was associated with significantly poorer PFS vs nonliver metastasis (adjusted hazard ratio, 3.40; 95% CI, 1.27-9.13; adjusted P = .01). Complete and partial responses were observed in 3 patients (21%) with liver metastasis vs 17 patients (63%) with nonliver metastases. Treatment-related grade 3 or 4 adverse events were observed in 8 patients (20%), 2 of whom discontinued therapy; there was 1 treatment-related death. Conclusions and Relevance This cohort study found a clinically significant prolongation of survival in older patients with dMMR mCRC who were treated with first-line pembrolizumab in routine clinical practice. Furthermore, liver vs nonliver metastasis was associated with poorer survival in this patient population, which suggests that the metastatic site has implications for survival outcome.

Bone autografts are frequently harvested for use in foot and ankle surgery. A commonly used harvest site is the iliac crest; however, because of known morbidity with this site, the tibia and calcaneus are attractive alternatives. There remains limited understanding regarding the osteogenic potential of autografts from each of these locations. In this review, we provided an update of the known data on bone autografts from the iliac crest, tibia, and calcaneus, focusing on the total cells harvested from each site as well as the presence of osteogenic osteoprogenitor cells. Level of Evidence: Level V, expert opinion.

Abstract Background Mendelian randomization (MR) studies are susceptible to metadata errors (e.g. incorrect specification of the effect allele column) and other analytical issues that can introduce substantial bias into analyses. We developed a quality control (QC) pipeline for the Fatty Acids in Cancer Mendelian Randomization Collaboration (FAMRC) that can be used to identify and correct for such errors. Methods We collated summary association statistics from fatty acid and cancer genome-wide association studies (GWAS) and subjected the collated data to a comprehensive QC pipeline. We identified metadata errors through comparison of study-specific statistics to external reference data sets (the National Human Genome Research Institute-European Bioinformatics Institute GWAS catalogue and 1000 genome super populations) and other analytical issues through comparison of reported to expected genetic effect sizes. Comparisons were based on three sets of genetic variants: (i) GWAS hits for fatty acids, (ii) GWAS hits for cancer and (iii) a 1000 genomes reference set. Results We collated summary data from 6 fatty acid and 54 cancer GWAS. Metadata errors and analytical issues with the potential to introduce substantial bias were identified in seven studies (11.6%). After resolving metadata errors and analytical issues, we created a data set of 219 842 genetic associations with 90 cancer types, generated in analyses of 566 665 cancer cases and 1 622 374 controls. Conclusions In this large MR collaboration, 11.6% of included studies were affected by a substantial metadata error or analytical issue. By increasing the integrity of collated summary data prior to their analysis, our protocol can be used to increase the reliability of downstream MR analyses. Our pipeline is available to other researchers via the CheckSumStats package (https://github.com/MRCIEU/CheckSumStats).

Background: The deep peroneal nerve (DPN) plays a role in afferent nociceptive dorsal midfoot joint pain perception. DPN neurectomy for treatment of symptomatic dorsal midfoot osteoarthritis allows early mobilization and weightbearing. The purpose of our study was to evaluate the patient satisfaction and pain relief after DPN neurectomy for treatment of chronic dorsal midfoot pain due to osteoarthritis. Methods: In this retrospective, IRB-approved, questionnaire-based study, we evaluated 48 patients (55 feet) with an average follow-up of 35.1 (range, 16-51) months who underwent DPN neurectomy at our institution between September 2017 and February 2021. There were 38 women and 10 men, 41 unilateral (22 right, 19 left) and 7 bilateral procedures, with an average age of 67.8 (range, 35-88) years at the time of surgery. A questionnaire that included questions regarding postsurgical dorsal midfoot pain relief, surgical result satisfaction, and current functional limitations was administered via telephone. Demographic information, patient responses, and complications were recorded. Results: Of the 48 patients, 80.8% were satisfied with the result of the surgery in relieving their dorsal midfoot pain, 84.6% would repeat the surgery under the same circumstances, 83.8% would recommend the surgery to a friend, 10.4% reported they wish they had undergone arthrodesis, 91.7% reported pain relief in the first 6 months, and 55.6% reported current activity limitations. Six feet (10.9%) underwent a second procedure with an average postoperative time of 20.5 (range, 1-36) months. Complications included 1 hematoma and deep wound infection, 1 DPN neuroma and superficial peroneal nerve entrapment, and 4 patients with inadequate pain relief. Conclusion: In this cohort, DPN neurectomy appeared to be a reasonable surgical alternative to arthrodesis for the management of chronic dorsal midfoot pain due to midfoot osteoarthritis after failed nonoperative management. Level of Evidence: Level IV, retrospective case series.

ImportanceThe association of chronic inflammation with colorectal cancer recurrence and death is not well understood, and data from large well-designed prospective cohorts are limited.ObjectiveTo assess the associations of inflammatory biomarkers with survival among patients with stage III colon cancer.Design, Setting, and ParticipantsThis cohort study was derived from a National Cancer Institute–sponsored adjuvant chemotherapy trial Cancer and Leukemia Group B/Southwest Oncology Group 80702 (CALGB/SWOG 80702) conducted between June 22, 2010, and November 20, 2015, with follow-up ending on August 10, 2020. A total of 1494 patients with plasma samples available for inflammatory biomarker assays were included. Data were analyzed from July 29, 2021, to February 27, 2022.ExposuresPlasma inflammatory biomarkers (interleukin 6 [IL-6], soluble tumor necrosis factor α receptor 2 [sTNF-αR2], and high-sensitivity C-reactive protein [hsCRP]; quintiles) that were assayed 3 to 8 weeks after surgery but before chemotherapy randomization.Main Outcomes and MeasuresThe primary outcome was disease-free survival, defined as time from randomization to colon cancer recurrence or death from any cause. Secondary outcomes were recurrence-free survival and overall survival. Hazard ratios for the associations of inflammatory biomarkers and survival were estimated via Cox proportional hazards regression.ResultsOf 1494 patients (median follow-up, 5.9 years [IQR, 4.7-6.1 years]), the median age was 61.3 years (IQR, 54.0-68.8 years), 828 (55.4%) were male, and 327 recurrences, 244 deaths, and 387 events for disease-free survival were observed. Plasma samples were collected at a median of 6.9 weeks (IQR, 5.6-8.1 weeks) after surgery. The median plasma concentration was 3.8 pg/mL (IQR, 2.3-6.2 pg/mL) for IL-6, 2.9 × 103pg/mL (IQR, 2.3-3.6 × 103pg/mL) for sTNF-αR2, and 2.6 mg/L (IQR, 1.2-5.6 mg/L) for hsCRP. Compared with patients in the lowest quintile of inflammation, patients in the highest quintile of inflammation had a significantly increased risk of recurrence or death (adjusted hazard ratios for IL-6: 1.52 [95% CI, 1.07-2.14];P = .01 for trend; for sTNF-αR2: 1.77 [95% CI, 1.23-2.55];P < .001 for trend; and for hsCRP: 1.65 [95% CI, 1.17-2.34];P = .006 for trend). Additionally, a significant interaction was not observed between inflammatory biomarkers and celecoxib intervention for disease-free survival. Similar results were observed for recurrence-free survival and overall survival.Conclusions and RelevanceThis cohort study found that higher inflammation after diagnosis was significantly associated with worse survival outcomes among patients with stage III colon cancer. This finding warrants further investigation to evaluate whether anti-inflammatory interventions may improve colon cancer outcomes.Trial RegistrationClinicalTrials.gov Identifier:NCT01150045

57 Background: Metastatic colorectal cancer (mCRC) with deficient DNA mismatch repair (dMMR) or microsatellite instability-high (MSI-H) show frequent and durable responses to programmed cell death -1 (PD-1) blockade. While the majority of these tumors are sporadics and observed in elderly patients, first-line data are limited to the KEYNOTE-177 study. Here, we report a consecutive series of elderly patients with dMMR mCRC treated with pembrolizumab in routine clinical practice that includes analysis of clinical outcome based on metastatic site. Methods: Patients with dMMR mCRC received first-line pembrolizumab (200 mg every 3 weeks) (N = 41) at Mayo Clinic and Mayo Clinic Health System (2015-2022). Clinicopathological features including metastatic site and molecular data ( BRAFV600E, KRAS) were analyzed in relationship to tumor response rate (RECIST version 1.1). Furthermore, these variables were also analyzed in relationship to patient progression-free survival (PFS) using Kaplan-Meier methodology and multivariable stepwise Cox regression. Results: Among patients with dMMR mCRC, 29/41 (70.7%) were female, 30 (78.9%) harbored BRAFV600E, and 32 (80%) were sporadic. Median age at start of treatment was 80.6 years (IQR of 75.9, 85.9) and median number of treatment cycles was 9 (IQR: 4, 20). At a median follow-up of 23 months (range, 3.0 to 88.5), patient median PFS was 21.3 months (95% CI: 6.4, 38.5). An overall response was observed in 48.8% (20 of 41) of patients including 13 (31.7%) complete (CR) and 7 (17.1%) partial responses (PR). The median duration of response was 42.2 months (95%CI: 8.6, NR). Patients with metastases that included liver had significantly poorer PFS compared to those with non-liver metastases (HRadj 3.40 (95%CI: 1.27-9.13); Padj= 0. 01). In this regard, responses (CR, PR) to pembrolizumab were observed in 3 (21.4%) patients with liver metastasis compared to 17 (62.9%) of those with non-liver metastases. Treatment-related grade 3 or 4 adverse events were observed in 9 (22.0%) patients of whom two discontinued therapy, and there was one treatment-related death. Conclusions: First-line therapy with pembrolizumab for dMMR mCRC significantly prolonged survival in an elderly patient population with manageable toxicity in routine clinical practice. Moreover, the survival benefit of pembrolizumab was significantly attenuated in patients with liver vs non-liver metastases.

256 Background: Current staging for colon cancer utilizing the American Joint Committee on Cancer TNM framework stratifies disease into groups according to how advanced the disease is and provides important standardized, individual prognostic information. Ideally, staging systems should exhibit hierarchical logic, with increasing stage reflecting worse prognosis. We sought to evaluate hierarchy within the 8th edition AJCC staging system for colon cancer. Methods: All patients with primary colon (including rectosigmoid) cancer diagnosed 2010-2017 were identified from the National Cancer Database (NCDB). Patients were only included if they carried a histologic diagnosis of invasive primary (non-recurrent) cancer, underwent radical surgery, and had complete pathologic staging data (T, N, M category data). Patients with missing follow-up data were excluded. Kaplan-Meier curves were used to assess overall survival by AJCC 8th edition pathologic summary stage group to determine whether staging was hierarchical for colon cancer. Multivariable modeling and log likelihood ratio test was then used to identify relative contributions of T and N variables to overall survival. Results: Among 270,584 colon cancer patients, pathologic staging was noted to be hierarchical by T category alone and by N category alone. However, summary staging was non-hierarchical in both instances. Multivariable modeling confirmed the AJCC non-hierarchy issue (colon HRs: 1, 1.54, 2.62, 2.60, 1.02, 2.15, and 4.38 for stage 1 as reference, 2a, 2b, 2c, 3a, 3b, 3c respectively). Multivariable modeling demonstrated that high T category (T4a, T4b) conferred the greatest risk of mortality based on hazard ratio (T4a HR 2.76, T4b HR 3.04), while high T category as well as high N category (N2a, N2b) contributed substantially to the survival model based on z-score. Further modeling assessing the predictive power of T and N category with respect to overall survival demonstrated that T category more strongly predicted overall survival than N category in colon cancer (likelihood chi-square test statistic pT:7009 vs pN:3586). Conclusions: Hierarchy in survival based on AJCC summary stage was not observed for patients with stage II-III colon cancer resulting in a paradoxical better observed survival with some stage III cancer subgroups compared to stage II cancer subgroups. High T category appears to more significantly impact survival than N category for patients with N0-N1 disease, while high N category appears more important for patients with T1-3 disease. Future revisions of the AJCC staging system should account for the differential impact of T and N category identified herein to more accurately confer prognostic information.

227 Background: Circulating tumor DNA (ctDNA) consists of small fragments of DNA released into the plasma from cancer cells. Tumor informed ctDNA testing by whole exome sequencing of the primary tumor coupled with multiplex polymerase chain reaction (PCR)-based next generation sequencing of cell free DNA in serum, can detect and quantify ctDNA, allowing for detection of minimal residual disease (MRD). Methods: We conducted a retrospective analysis of 120 patients with colorectal cancer who had at least one tumor-informed ctDNA MRD assay completed between May 6, 2019, and July 1, 2022, at Mayo Clinic, Rochester. Disease recurrence was defined as radiographic evidence consistent with recurrence with or without biopsy confirmation. Data are presented descriptively, including number of ctDNA assays completed, ctDNA positivity prior to disease recurrence, and ctDNA concordance with carcinoembryonic antigen (CEA). The study protocol was exempt after review by the Mayo Clinic Institutional Review Board. Results: One-hundred twenty patients were included in the study with median age at initial disease diagnosis of 67.0 years. Sixty-four percent were male and 94% were white. At time of initial diagnosis, 10 had stage I, 23 stage II, 60 stage III, and 25 stage IV disease. In 120 patients, 476 ctDNA assays were performed, and 110 recurrences were observed among 62 patients. There were 39 instances in which ctDNA was obtained prior to clinical detection of recurrence and of these, at least one ctDNA assay was positive in 28 cases (72%). CEA was obtained prior to recurrence in 88 instances and was elevated in only 39 cases (44%). Among 37 instances where both ctDNA and CEA testing were obtained prior to recurrence, ctDNA was positive in 27 cases (73%) while CEA was positive in 14 cases (38%). ctDNA was positive in 83% of recurrences involving liver and 62.5% of recurrences involving only the lungs. ctDNA and CEA positivity are shown by location of recurrence. ctDNA and CEA were discordant in 44% of instances in which the assays were completed within 2-weeks of each other. Results of a ctDNA assay impacted management decisions in 16% of cases. Conclusions: ctDNA detected 72% of recurrences with higher rates of detection in liver versus lung metastasis. ctDNA performed superiorly to serum CEA in detection of recurrence, suggesting a role in disease surveillance. However, ctDNA impacted disease management in only 16% of patients, suggesting need for better patient selection and further study for ctDNA-based disease management strategy (more details will be reported). [Table: see text]

118 Background: Anti-VEGF is widely used in the treatment (trt) of metastatic colorectal cancer (mCRC). Only studies with bevacizumab (BEV) have shown survival benefit (bnf) in first line trt. The magnitude of bnf might differ based on the metastatic (met) site and the chemotherapy regimen (CTR) with which BEV is partnered. ARCAD database contains individual patient data (IPD) of randomized trials that evaluated BEV+ CT. In this pooled analysis, we aimed to evaluate BEV bnf in mCRC with lung metastases (mets) either as single or multiple sites. Methods: IPD from four trials (AVF2107g, N016966, AVF2192g, AGITG) comparing CT +/- BEV were pooled. The primary endpoint, overall survival (OS), was estimated using Kaplan-Meier method and prognostic value of lung mets was evaluated by stratified Cox models according to number and type of met sites and CTRs, oxaliplatin or irinotecan (OX/IRI) based. The predictive bnf of BEV was evaluated by interaction test (int) between trt and lung mets status in subgroups and considered as significant (sig) with a P < 0.1. Results: 2728 patients (pts) with known met sites and survival data were pooled. 1020 pts had single met site, 133 had only lung mets. 1708 pts had multiple met sites, 1008 had lung mets. Pts characteristics were well balanced. Sig OS bnf of BEV was observed in the whole population. In pts subgroup according to the presence or absence of lung mets, sig bnf of BEV were observed with a non-sig int ( Pint=.590). Non-sig bnf of BEV was observed in pts with single site regardless of met site (lung or no lung) or CTR. Sig bnf of BEV was observed in pts with multiple sites without lung mets whatever the CTRs. While sig bnf of BEV was observed in pts with multiple sites with lung mets, we found a sig int between BEV and OX/IRI-based regimens ( Pint=.022). The bnf of BEV was observed with IRI-based regimen but not in OX-based regimen. The bnf of BEV appears greater in multiple sites without lung mets than with lung mets with a sig stratified log-rank test ( PLRT<.001). Conclusions: In pts with multiple sites mCRC, a statistically sig OS bnf of BEV added to CT was observed mainly among pts without lung mets. The overall effect of CT partner choice when combined with BEV can be different. In pts with single site, BEV did not seem to improve OS but the evaluation of efficacy of BEV in presence or absence lung mets was based on small number of pts and needs to be evaluated in trials with larger pts sample, especially trials including pts with single site lung mets. [Table: see text]