Association of CA19-9 and tumor size in treatment monitoring for patients with metastatic pancreatic ductal adenocarcinoma (PDAC)

693

Background: Although modern cancer treatment has significantly prolonged patient’s life, it comes with a high financial cost. Based on an NIH report on Financial Burden of Cancer Care, treating PDAC costs $108K, $18K, and $125K for initial treatment, during follow up, and in last year of life, respectively. Of these, CA19-9 and CT studies are obtained concurrently to evaluate tumor burden whose cost can be reduced by decreasing imaging frequency when CA19-9 remains stable. As a pilot study, we evaluated whether changes in CA19-9, an inexpensive laboratory study commonly used for monitoring treatment response, correlates with tumor size change on imaging studies. A positive correlation may lead us to design future studies to evaluate whether stable CA19-9 can serve as an indicator for stable disease on CT scan such that imaging frequency (and cost) may be reduced. Methods: We retrospectively identified PDAC patients from our tumor registry from 2016 to 2019. Subjects were included if they met the following criteria: 1) diagnosed with PDAC 2) had at least 2+ CA19-9 and CT/MR follow up assessments with the laboratory and imaging studies within one month of each other, and 3) had measurable lesions as defined by RECIST 1.1 criteria. Due to limited resources, we limited the maximum number of lesions to 4 instead of the usual 5 for RECIST 1.1. Two-dimensional orthogonal tumor sizes were measured on axial images with the largest cross-section. Changes in the values were obtained serially (from the immediately prior study). Nonparametric correlations (Spearman’s rho) were used to evaluate monotonicity. The significance level was set at p < 0.05. Results: We screened 300 subjects from the tumor registry and identified 23 subjects suitable for our study. 13 subjects were female and 10 were male with ages ranging from 35 to 84. We identified 55 target lesions and 128 assessments (with both CA19-9 and imaging) from the 23 subjects. We analyzed the log absolute and log relative change in CA19-9 with change in tumor area. When absolute CA19-9 value, absolute change in CA19-9, and relative change in CA19-9 were tested against the absolute change in tumor size, the correlation was significant for the absolute value and absolute change of CA19-9 (p < 0.01), but not for relative change of CA19-9 (p < 0.11). When tested against relative change in tumor size, all three values were highly significant (p < 0.001). Conclusions: Our finding of direct correlations between changes of CA19-9 and relative change of tumor size on imaging suggests that CA19-9 can serve as a surrogate measure of relative change of tumor burden for patients undergoing treatment. This provides motivation for future studies evaluating the possibility that stable CA19-9 can represent stable tumor burden such that expensive imaging studies may be obtained at longer time intervals to reduce financial cost to patients.

The Wnt signaling pathway in gastrointestinal cancers

807

Background: Activation of the Wnt signaling pathway leads to increases in β-catenin levels, which subsequently increases transcription of various genes, including those involved in cell proliferation. Dysregulation of the Wnt signaling pathway has been observed in numerous gastrointestinal (GI) cancers. Here we examine Wnt pathway activation across all GI cancers by investigating alterations in certain genes of the Wnt pathway, which may identify patients eligible for clinical trials. Methods: The Oncomap ExTra genomic profiling assay utilizes tumor-normal, whole-exome, whole-transcriptome DNA and RNA sequencing to identify somatic alterations in tumors. The assay detects single-nucleotide substitutions, indels, copy number alterations, alternative transcripts, and gene fusions. Alterations in genes that activate Wnt signaling and their frequency across all GI cancers was determined. Results: A total of 1928 patients assayed April 2018 to July 2022 were included. The Wnt signaling pathway was activated in 922 (47.8%) patients. Wnt pathway activation varied substantially across GI cancers, from 81.1% in colorectal cancer (CRC) to 3.4% in anal cancer. APC was the most commonly altered gene in CRC, small bowel and biliary carcinomas. CTNNB1 was predominant in liver (41.2%), MEN1 in neuroendocrine (14.6%), and RNF43 in gastric (9.4%) cancer. Of 921 patients with alterations in the Wnt pathway, 5.2% had a co-mutation in another Wnt pathway-related gene. RSPO2/3 fusions were found in 4 CRC, 1 stomach, 1 biliary, and 1 small bowel cancer and were mutually exclusive with other alterations in the Wnt pathway. Conclusions: Wnt signaling is activated in about half of all GI cancers, and APC alterations are the most frequently observed. Whole transcriptome profiling allowed us to identify RSPO2/3 fusions, which also contribute to activation of the Wnt pathway. Wnt activation appears to be a particularly important in CRC, with 81.1% of CRC having a Wnt pathway alteration. Our results highlight the therapeutic potential of targeting the abnormal Wnt/β-catenin signaling pathway in GI malignancies. [Table: see text]

Interplay of Immunosuppression and Immunotherapy Among Patients With Cancer and COVID-19

Importance

Cytokine storm due to COVID-19 can cause high morbidity and mortality and may be more common in patients with cancer treated with immunotherapy (IO) due to immune system activation.

Objective

To determine the association of baseline immunosuppression and/or IO-based therapies with COVID-19 severity and cytokine storm in patients with cancer.

Design, Setting, and Participants

This registry-based retrospective cohort study included 12 046 patients reported to the COVID-19 and Cancer Consortium (CCC19) registry from March 2020 to May 2022. The CCC19 registry is a centralized international multi-institutional registry of patients with COVID-19 with a current or past diagnosis of cancer. Records analyzed included patients with active or previous cancer who had a laboratory-confirmed infection with SARS-CoV-2 by polymerase chain reaction and/or serologic findings.

Exposures

Immunosuppression due to therapy; systemic anticancer therapy (IO or non-IO).

Main Outcomes and Measures

The primary outcome was a 5-level ordinal scale of COVID-19 severity: no complications; hospitalized without requiring oxygen; hospitalized and required oxygen; intensive care unit admission and/or mechanical ventilation; death. The secondary outcome was the occurrence of cytokine storm.

Results

The median age of the entire cohort was 65 years (interquartile range [IQR], 54-74) years and 6359 patients were female (52.8%) and 6598 (54.8%) were non-Hispanic White. A total of 599 (5.0%) patients received IO, whereas 4327 (35.9%) received non-IO systemic anticancer therapies, and 7120 (59.1%) did not receive any antineoplastic regimen within 3 months prior to COVID-19 diagnosis. Although no difference in COVID-19 severity and cytokine storm was found in the IO group compared with the untreated group in the total cohort (adjusted odds ratio [aOR], 0.80; 95% CI, 0.56-1.13, and aOR, 0.89; 95% CI, 0.41-1.93, respectively), patients with baseline immunosuppression treated with IO (vs untreated) had worse COVID-19 severity and cytokine storm (aOR, 3.33; 95% CI, 1.38-8.01, and aOR, 4.41; 95% CI, 1.71-11.38, respectively). Patients with immunosuppression receiving non-IO therapies (vs untreated) also had worse COVID-19 severity (aOR, 1.79; 95% CI, 1.36-2.35) and cytokine storm (aOR, 2.32; 95% CI, 1.42-3.79).

Conclusions and Relevance

This cohort study found that in patients with cancer and COVID-19, administration of systemic anticancer therapies, especially IO, in the context of baseline immunosuppression was associated with severe clinical outcomes and the development of cytokine storm.

Trial Registration

ClinicalTrials.gov Identifier: NCT04354701.

Ensemble voting decreases false positives in AI second-observer reads for detecting colorectal cancer

141

Background: Colorectal cancer (CRC) is the second leading cause of cancer-related deaths, and survival can be improved if early, suspect imaging features on CT of the abdomen and pelvis (CTAP) can be routinely identified. At present, up to 40% of these features are undiagnosed on routine CTAP, but this can be improved with a second observer. In this study, we developed a deep ensemble learning method for detecting CRC on CTAP to determine if increasing agreement between ensemble models can decrease the false positives detected by artificial intelligence (AI) second-observer. Methods: 2D U-Net convolutional neural network (CNN) containing 31 million trainable parameters was trained with 58 CRC CT images from Banner MD Anderson (AZ) and MD Anderson Cancer Center (TX) (51 used for training and 7 for validation) and 59 normal CT scans from Banner MD Anderson Cancer Center. 20 of the 25 CRC cases from public domain data (The Cancer Genome Atlas) were used to evaluate the performance of the models. The CRC was segmented using ITK-SNAP open-source software (v. 3.8). To apply the deep ensemble approach, five CNN models were trained independently with random initialization using the same U-Net architect and the same training data. Given a testing CT scan, each of the five trained CNN models was applied to produce tumor segmentation for the testing CT scan. The tumor segmentation results produced by the trained CNN models were then fused using a simple majority voting rule to produce consensus tumor segmentation results. The segmentation was analyzed by the percentage of correct detection, the number of false positives per case, and the Dice similarity coefficient (DSC). If parts of the CRC were flagged by AI, then it was considered correct. A detection was considered false positive if the marked lesion did not overlap with any CRC; contiguous false positives across different slices of CT image were considered a single false positive. DSC measures the quality of the segmentation by measuring the overlap between the ground-truth and AI detected lesion. Results: Our results showed that increasing the agreement between the 5 models dramatically decreases the number of false positives per CT at the expense of slight decrease in accuracy and DSC. This is described in the table. Conclusions: Our results show that AI-based second observer can potentially detect CRC on routine CTAP. Although the initial result yields high false positives per case, ensemble voting is an effective method for decreasing the false positives with a slight decrease in accuracy. This technique can be further improved for eventual clinical application.[Table: see text]

Comparison of segmentation methods to improve throughput in annotating AI-observer for detecting colorectal cancer

142

Background: Colorectal cancer (CRC) is the second leading cause of cancer-related deaths, and its outcome can be improved with better detection of incidental early CRC on routine CT of the abdomen and pelvis (CTAP). AI-second observer (AI) has the potential as shown in our companion abstract. The bottleneck in training AI is the time required for radiologists to segment the CRC. We compared two techniques for accelerating the segmentation process: 1) Sparse annotation (annotating some of the CT slice containing CRC instead of every slice); 2) Allowing AI to perform initial segmentation followed by human adjustment. Methods: 2D U-Net convolutional neural network (CNN) containing 31 million trainable parameters was trained with 58 CRC CT images from Banner MD Anderson (AZ) and MD Anderson Cancer Center (TX) (51 used for training and 7 for validation) and 59 normal CT scans from Banner MD Anderson Cancer Center. Twenty of the 25 CRC cases from public domain data (The Cancer Genome Atlas) were used to evaluate the performance of the models. The CRC was segmented using ITK-SNAP open-source software (v. 3.8). For the first objective, 3 separate models were trained (fully annotated CRC, every other slice, and every third slice). The AI-annotation on the TCGA dataset was analyzed by the percentage of correct detection of CRC, the number of false positives, and the Dice similarity coefficient (DSC). If parts of the CRC were flagged by AI, then it was considered correct. A detection was considered false positive if the marked lesion did not overlap with CRC; contiguous false positives across different slices of CT image were considered a single false positive. DSC measures the quality of the segmentation by measuring the overlap between the ground-truth and AI detected lesion. For the second objective, the time required to adjust the AI-produced annotation was compared to the time required for annotating the entire CRC without AI assistance. The AI-models were trained using ensemble learning (see our companion abstract for details of the techniques). Results: Our results showed that skipping slices of tumor in training did not alter the accuracy, false positives, or DSC classification of the model. When adjusting the AI-observer segmentation, there was a trend toward decreasing the time required to adjust the annotation compared to full manual segmentation, but the difference was not statistically significant (Table; p=0.121). Conclusions: Our results show that both skipping slices of tumor as well as starting with AI-produced annotation can potentially decrease the effort required to produce high-quality ground truth without compromising the performance of AI. These techniques can help improve the throughput to obtain a large volume of cases to train AI for detecting CRC.[Table: see text]

Age-associated mutations in RAS-mutated versus RAS-nonmutated metastatic colorectal cancer

171

Background: Mutational profiling is recommended for selecting targeted therapy for metastatic colorectal cancer (mCRC). Evidence suggests that among patients with mutations in one of three RAS genes who underwent resection of liver metastasis, those with early onset mCRC had worse outcomes compared to those with late onset mCRC. The goal of this study was to explore whether other mutated genes in mCRC exhibit an association between age and wild type versus mutant RAS status. Methods: Between October 2018 and October 2020, 974 tumor samples from patients with mCRC were identified. Samples meeting requirements were profiled with the Oncotype MAP Pan-Cancer Tissue test, which sequences 257 genes from tumor tissue, including all 3 RAS genes ( HRAS, KRAS, NRAS). Using the Oncotype MAP assay, single base variants, indels, copy number alterations and structural variants/fusions were identified. Tumor mutational burden (TMB) and microsatellite instability (MSI) were also determined. To identify genes for which there was an association between age group (patients ≤50 years vs >50 years) and RAS status we used Fisher’s Exact Test. Results: Of the 974 samples, 840 met minimum tumor tissue requirements for DNA sequencing (3mm2 and 15% tumor cellularity). Of these, 759 samples were successfully sequenced for NGS. Median turnaround time from the date of sample accessioning to the date of laboratory report was 5 days (interquartile range, IQR, 4-6 days). TMB varied from 0-227 mutations per megabase (median 6, IQR 4-8), and was high (≥10 mut/Mb) in 117 samples (15%). Of 775 specimens processed for MSI, 714 could be measured and approximately 7% were MSI-high. A total of 496 RAS variants were identified, of which 391 were pathogenic, likely pathogenic, or variants of unknown significance (349 KRAS, 34 NRAS, 8 HRAS). Of the 27 genes with at least 78 mutations in the data set, there was an association between RAS status and patient age for mutations at SMAD4, ABCC1, and RICTOR (Fisher’s Exact test, P < 0.05). For all three, mutations at these genes are relatively more prevalent in samples from young RAS wild type patients compared to young RAS mutant patients (Table). Conclusions: The Oncotype MAP Pan-Cancer Tissue test identified numerous genomic changes in mCRC samples. There appears to be an association between age group and RAS status for three mutated genes, SMAD4, ABCC1, and RICTOR. The clinical implication is unclear and warrants further investigation with outcomes data.[Table: see text]

Molecular profiling to identify potential therapeutic targets in hepatocellular carcinoma

471

Background: Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer and is often diagnosed at an advanced stage with limited effective therapies. The advent of comprehensive genomic molecular profiling has the potential to identify novel therapeutic options in the treatment of HCC. In this descriptive clinical utility study, we evaluated the utility of the Oncotype MAP Pan-Cancer Tissue (MAP) test to identify potential therapeutic options, including clinical trials. Methods: Between October 2018 and October 2020, we identified 41 samples from patients with HCC submitted for MAP testing. The MAP test uses tumor tissue to identify single nucleotide variants, indels, copy number alterations, and select structural variants and fusions by next-generation sequencing (NGS) of a 257 gene panel. Tumor mutational burden and microsatellite instability are also determined. A custom immunohistochemical (IHC) panel is also performed. Results from NGS and IHC are run against a proprietary knowledgebase of genomic and proteomic data that includes FDA approvals, NCCN Recommendations and published biomarker data on potentially targetable alterations. Eligibility for ongoing clinical trials is determined using the NCI database. Results: Of the 41 samples, 37 (90%) met minimum tissue requirements (3mm2 and 15% tumor cellularity) for DNA sequencing. Of these 37 samples, 36 (97%) were successfully sequenced for NGS testing. Median turnaround time from the date of accessioning to the date of laboratory report was 5 days (interquartile range (IQR) 4-6 days). The most frequently identified genomic variants characterized as pathogenic, or unknown significance, were TP53, CTNNB1 and FAT1 genes. Thirty-two samples (86%) had a genomic alteration that could potentially direct treatment. Six samples (16%) had findings directing to an approved treatment for HCC, 4 (11%) had findings for an approved treatment of a different tumor type, and 22 (59%) had findings for one or more clinical trials. Conclusions: The Oncotype MAP Pan-Cancer Tissue test identified molecular variants that could be used to inform treatment decisions in 86% of HCC samples, including 16% to an approved HCC therapy. The Oncotype MAP test may be considered as another tool in the management of advanced HCC patients.

Infection Masquerading as Recurrence of Pancreatic Ductal Adenocarcinoma: A Cautionary Tale

We present a case of a 59-year-old male undergoing adjuvant chemotherapy for his pancreatic adenocarcinoma post-surgical resection. He had an acute rise in carbohydrate antigen (CA) 19-9 level, which raised suspicion of metastatic disease. Instead, the patient was diagnosed to have a liver abscess, the treatment of which brought the CA 19-9 level back to normal. Unfortunately, although CA 19-9 is Food and Drug Administration (FDA)-approved tumor marker for pancreatic cancer, it is also elevated in several benign conditions, causing fear of cancer and unnecessary diagnostic workup. Hence, caution is necessary for interpreting the significance of its elevation.

A phase Ib/II study of olutasidenib in patients with relapsed/refractory IDH1 mutant solid tumors: Safety and efficacy as single agent

e16643

Background: Isocitrate dehydrogenase 1 mutations (mIDH1) are present in a variety of solid tumors resulting in production and accumulation of (R)-2-hydroxyglutarate causing DNA hypermethylation and promoting tumorigenesis. Olutasidenib is an oral, potent and selective inhibitor of mutated IDH1 protein. We report preliminary results from the ongoing, first-in-human, Phase 1, open-label, single-arm study of olutasidenib in non-CNS solid tumors. Methods: Patients with advanced relapsed/refractory (R/R) mIDH1 solid tumors received olutasidenib 150 mg BID, orally. Following a dose confirmation cohort (Phase 1b), patients with intrahepatic cholangiocarcinoma (IHCC), chondrosarcoma (CS), or unspecified mIDH1 solid tumors (Other) were enrolled in a Phase 2 efficacy evaluation (NCT: 03684811). Results: As of 31-Oct-2019, 44 patients with relapsed or refractory mIDH1 solid tumors were treated with olutasidenib. Diagnosis included: IHCC (n = 26), CS (n = 13), and Other (n = 5). The median age was 58 years (range: 29-81) and 43% were male. Median number of prior treatments was 2 (1-10). mIDH1 status was locally determined (IHC, NGS or PCR): R132C (61%), R132G (7%), R132S (7%), R132H (2%), R132L (2%), Others (2%) & unspecified (18%). Fourteen patients discontinued treatment (disease progression [n = 6; 3 IHCC, 2 CS, 1 Other], AE [n = 4; 3 IHCC, 1 CS], PI decision [n = 3; IHCC] & withdraw consent [n = 1; IHCC]). Treatment emergent adverse events (all grades, regardless of attribution) that occurred in > 15% of pts were: nausea (43%), fatigue (25%), decreased appetite (22%), AST increase (18%), ALT increase (16%), and constipation (16%). No protocol-defined DLTs occurred. Best responses by tumor type are shown in the table. Conclusions: Single agent olutasidenib at 150 mg BID demonstrates acceptable safety and tolerability with preliminary clinical activity in patients with R/R mIDH1 solid tumors. Updated safety and clinical activity, as well as exploratory evaluations of PK/PD will be provided. Clinical trial information: 03684811 . [Table: see text]

Phase II trial of BPM31510-IV plus gemcitabine in advanced pancreatic ductal adenocarcinomas (PDAC)

723

Background: BPM31510-IV is an Ubidecarenone (CoQ10) drug-lipid conjugate nanodispersion targeting metabolic machinery in cancer, shifting bioenergetics from lactate dependency towards mitochondrial OxPhos to generate ROS and activate apoptosis. An MTD of BPM31510-IV in combination with gemcitabine was established at 110mg/kg in a Phase I clinical trial, which determined the dose for the Phase 2 investigation. Methods: Eligible patients (aged ≥ 18 y) with relapsed/refractory PDAC to standard treatment (ST) and met inclusion/exclusion criteria were recruited. Patients received 110mg/kg IV BPM31510 in combination with gemcitabine in a 144-hour infusion. Tumor response was evaluated at week 10 and then every 8 weeks. Study endpoints assessed were Overall Response Rate (ORR), Overall Survival (OS), Progression-Free Survival (PFS), Time to Progression (TTP), Tumor Response using Adaptive Molecular Responses (multi-omic molecular profiling), changes in CA 19-9 levels and patient reported Quality of Life (QOL) using the validated FACT-HEP PRO. A comprehensive multi-omic profiling for identification of biomarkers for patient stratification was explored. Results: Of the 35 patients enrolled to receive therapy, 18 patients met criteria of an adequately treated cohort (ATC- received BPM31510-IV + gemcitabine for 30 days over 2 cycles and had a RECIST 1.1 evaluation) while remaining (n = 17) had progressive disease (PD). Half of the ATC population (n = 9/18, 50%) achieved best ORR of stable disease (SD); 10/18 (55 %) demonstrated SD as best response at target lesions and 8/18 demonstrated SD at end of Cycle 2. The mTTP was 121 days (70 – 147, 95% CI); PFS 118 days (70 – 131, 95% CI) and OS 218 days (131 – 228, 95% CI), respectively. Overall, BPM31510-IV was well tolerated; the most common AE’s were GI related. Conclusions: The efficacy signal observed in this heavily pretreated population in addition to the toxicity profile warrants further clinical investigation of BPM31510-IV + gemcitabine in advanced PDAC. Clinical trial information: NCT02650804 . [Table: see text]

Over-detection of colonic abnormalities on CTAP and a decrease with experience: A simulation of machine learning

68

Background: Artificial intelligence (AI) can potentially improve patient care by assisting physicians as demonstrated with the recent approvals for technologies that detect intracranial hemorrhage on CT exams of the head. AI also has potential for assisting early detection of colorectal cancer (CRC) on routine CT abdomen and pelvis (CTAP). We assessed the difference in detection of abnormal colonic findings between an expert reader (JC) and amateur readers (ARs). Methods: ARs consisting of two third year medical students (RB - AR1, ZG - AR2) studied 20 CTAP for tracing the colon and identifying pathology. Their search pattern and assessment of the colon was then evaluated by an expert radiologist (JC). They then spent two hours reviewing abnormalities in 10 scans with JC, who highlighted suspicious neoplastic findings such as colonic wall thickening, fat stranding, edema, masses, and abnormal lymph nodes. The ARs then individually read 203 CTAP scans to assess for these suspicious findings. The studies were from a single institution and were reported in a prior study in 2019 GI-ASCO. The findings of the ARs were then compared to those of the expert reader and the initial reader for each study. Data was analyzed using t-test with 2 tails. Results: The incidence of suspicious neoplastic findings was 87% and 81% for AR1 and AR2, respectively, compared to 18% in the initial reads and 33% for expert reader (p=0.01). Greatest discordance were 94% and 87% between AR1 and AR2 to the initial reads. Additionally, the incidence of suspicious findings between the first and last 20 cases (p=0.03 and 0.17) examined by ARs declined from 79 to 40% for AR1 and 69 to 55% for AR2. Conclusions: ARs are capable of detecting CRC features on CTAP from ED, but with higher false-positive (FP) rate than trained experts. The FP rate decreases with increasing experience. ARs learning course simulates AI which will likely yield high FP rate with initial training, but with improving FP with deep training, especially with larger volume of normal variants.

Circulating free tumor DNA copy number index (CNI) as a predictor of therapeutic response in pancreatic ductal adenocarcinomas (PDAC)

261

Background: Cell-free tumor DNA (cfDNA) has potential to provide minimally invasive patient specific biomarkers to monitor tumor burden. Tumor-specific copy number instability (CNI) are used to quantify tumor-derived cfDNA in the plasma. We prospectively computed CNI Scores of cfDNA to compare with radiological and Ca 19-9 responses. Methods: In a laboratory blinded, prospective single-institution study, 119 plasma samples from 33 patients (pts) with PDAC were analyzed. Time-points were at baseline (C1), 2nd (C2) and 3rd (C3) cycle of systemic therapy. Tumor cfDNA was measured with a CNI scoring assay that quantifies cfDNA with somatic macro-alterations. CNI Score (CNIs) of 31 was defined as ref. range (97.5 % - control group; N = 135), pts below this threshold were censored. Progression of disease (PD) defined as C3 CNIs > 93 (3-fold threshold) and difference to the baseline > 31 (dispersion of reference population). Mutant KRAS in plasma was measured using ddPCR in a subset 22 pts. Pts with an increase of > 0.06% (critical difference) were classified PD. Radiologic imaging results were compared with CNIs and CA19-9 changes from baseline to C3, respectively. Results: By standard radiological imaging 33 pts were classified as: 14 PR/CR, 10 SD, 9 PD. 27/33 pts (81%) were evaluable by CNIs which ranged from decrease of 2017 - increase of 645. The C3 CNI classifier yielded a sensitivity of 86% for predicting PD and 95% for SD/PR/CR. KRAS classification yielded an accuracy of 72%, and only 3/9 PD were accurately predicted (33%). 26/33 pts were secretors evaluable by CA19-9. Only 2/8 PD pts showed increasing values in CA19-9 and 6/8 of evaluable by CNI; 5/6 showed increasing CNI scores. 3/20 deemed as SD on imaging with increasing values of CA19-9 were noted to have decreasing CNIs. CNI Score classification was significantly better than CA19-9 (P = 0.001 and 0.63, respectively). Conclusions: Our evaluation of a comparative study on cfDNA and CA19-9 versus imaging suggest that CNI quantification is potentially a more reliable blood-based marker for early assessment of efficacy to systemic therapy in PDAC. Furthermore, for patients not expressing CA19-9 it could serve as an alternative monitoring aid.

Early detection of lower GI tract tumors by dedicated assessment of the colon on routine computed tomography (CT) imaging: An observational study

510

Background: We have previously reported that up to 48% of the early features of colorectal cancer (subtle wall thickening, pericolonic stranding, and small lymph nodes in the draining nodal station) were not identified on the original CT abdomen and pelvis (CTAP) reports. This resulted in a 36% decrease in five-year survival based on historical data. In this report, we assessed whether dedicated assessment of the colon on routine CT scans could lead to early detection of colorectal cancer. Methods: 210 CTAPs over a three-month period were screened from the emergency room records at a tertiary care hospital. 194 scans met eligibility. Exclusion criteria included: cases known to the evaluating radiologist and age ≤ 19 or > 89 years. No study was excluded for suboptimal image quality. The original report was reviewed for abnormalities involving the colon, mesentery and bowel and was recorded. A blinded evaluation of the eligible case was then performed by a board-certified radiologist with attention specifically to the colon and the mesentery for the suspicious early features of CRC. The concordance and discordance was then tabulated. Discordant findings were re-evaluated to determine if the discordance was true. Results: 72/194 patients were male, median age 44.5 years (range 20 - 89). 55/194 patients (29.1%) included in the study were noted to have suspicious features. 26 had abnormal lymph nodes, 24 had abnormal colonic wall thickening and 16 had pericolonic stranding and/or wall edema. 45/55 studies were truly discordant from the original interpretation. These included one missed colorectal cancer (confirmed), one likely small bowel neuroendocrine tumor (no follow up), and one likely transitional cell carcinoma of the right renal pelvis (no follow up). Conclusions: Dedicated search of the colon and mesentery on CTAP can identify subtle findings, although their true relevance is being evaluated in a larger future study. Our observational data does indicate that there maybe a potential role for a focused evaluation of the colon and mesentery on routine CTAP in an attempt to potentially increase the rate of cancer detection especially in younger low-average risk patients.

Circulating tumor DNA may correlate with tumor size changes following therapy

233

Background: Pancreatic cancer has significant mortality at five years, even in resectable disease. Recent effort has been dedicated to identify a more specific tumor marker for screening and assessing tumor response, in part because 10% of the population does not produce CA19-9. Detection and quantification of circulating tumor DNA (ctDNA) in the bloodstream is a novel concept for screening and treatment response assessment. This study examined possible correlations between ctDNA levels and various aspects of pancreatic cancer in a total of 17 patients receiving treatment at Banner MD Anderson Cancer Center. Methods: Present study is approved by our local IRB. Research was conducted according HIPPA regulation. Subjects on the present study were obtained from the list of patients participating in our ctDNA trial. A total of 17 subjects were identified from the list. Their ctDNA index levels were obtained from the sponsor (Chronyx) at baseline and following each cycle of the treatment. For each CT scan and each ctDNA study, they are considered the same time if they are obtained within 4 weeks of each other. The sizes of the primary tumor and the largest metastatic lesion were on a transverse image at the largest extent of the lesion. Data was analyzed with Spearman's correlation. Results: Baseline ctDNA levels did not correlate with patient demographic data (N = 17; gender, p = 0.63; age, p = 0.82), baseline size of primary mass on CT scan (N = 16; p = 0.85), baseline vessel involvement on CT Scan (N = 17; p = 0.58), presence of metastasis on CT scan (N = 17; p = 0.78), size of largest metastasis on CT scan (N = 17; p = 0.85), presence of peripancreatic lymph nodes on CT scan (N = 17; p = 0.45), or overall survival (N = 8; p = 0.6). However, there is a trend toward correlating the change in ctDNA and change in size on CT scan following treatment (N = 7; p = 0.12). Conclusions: ctDNA at baseline appears to be secreted independent of the primary tumor size, location, or presence of metastasis. However, changes in ctDNA does seem to correlate with changes in tumor size following treatment. Although our data was not statistically significant, this may be related to the low sample size. With larger sample size, it is expected that changes in ctDNA may prove to correlate with changes in tumor size.

Phase I/IIb trial: In-situ vaccine for metastatic colorectal cancer

TPS871

Background: Except for MSI-H tumors, CRC does not respond to immunotherapy. CRC does respond to the graft vs. tumor (GVT) immune effect that occurs after allogeneic stem cell transplantation. GVT is associated with GVHD toxicity which limits the clinical application. A bioengineered allograft (BAG) has been developed which can elicit host-mediated GVT-like effects without GVHD toxicity, chemotherapy conditioning or a HLA-matched donor. BAG are Th1 memory cells derived from blood of healthy donors with CD3/CD28 microbeads attached. These cells have immunomodulatory properties which enable modulation of Th1/Th2 balance and dysregulation of immunosuppressive circuits. We are evaluating the safety and efficacy of BAG in third-line mCRC. Methods: The study uses a standard 3+3 design followed by an expansion phase with the optimal dosing pattern. The protocol has four components: (A) priming; (B) in-situ vaccination; (C) extravasation and trafficking; and (D) counter immune suppression/avoidance. Priming involves intradermal injections of BAG cells which activates NK cells and develops allo-specific Th1/Tc1 immunity. In-Situ vaccination involves tumor cryoablation to release endogenous HSP which chaperone tumor neoantigens, followed immediately by the intralesional injection of BAG cells as adjuvant. Released HSP are engulfed and processed by immature dendritic cells (DC) attracted to the tissue damage. The inflammatory microenvironment created by the BAG and the subsequent allo-rejection response amplified by the priming induces DC maturation. These DC display processed tumor antigens on upregulated MHCI/II and express co-stimulatory CD80/86 enabling priming of a tumor-specific Th1/Tc1 response. CD40L and interferon-gamma expressed by BAG activates allo-specific and tumor-specific memory cells upon intravenous infusion, permitting trafficking to tumor. The host rejection of BAG releases endogenous danger signals creating a sustained systemic inflammatory cytokine release which serves to counter-regulate immunosuppressive mechanisms. Longitudinal CT scans biopsies, PBMC and serum samples are collected for analysis to verify immune events within each phase of the protocol. Clinical trial information: NCT02380443.

Skeletal metastases in advanced pancreatic ductal adenocarcinoma (PDAC): A retrospective analysis

245

Background: Skeletal metastasis (SM) in advanced PDAC is an infrequent occurrence and has been previously reported to be < 2.5%. However; pathological fractures in these patients can result in intractable pain, immobilization and a significant deterioration in quality of life. Methods: A retrospective analysis was conducted of patients (pts) with advanced PDAC receiving palliative chemotherapy. Data collection included age, gender, ECOG, sites of disease, and overall survival (OS). Statistical analysis included Kaplan Meier survival analysis. Results: The 135 pts included had a median age of 65.8 years (range: 53.7–91.3); 5 (31.2%) were women and 11 (68.7%) had an ECOG performance status of 0 or 1. A majority of patients received combination therapy that was either gemcitabine or 5-flurouracil based. Sixteen pts (11.8%) had skeletal metastasis with the primary tumor located in the pancreatic body/tail (11 pts - 68.7%).The sites of SM included thoracic vertebrae (8), lumbar vertebrae (5), pelvis (5), ribs (4), sacrum (4), scapula (3), acetabulum (2), cervical vertebrae (2), femoral head (2), sternum (1) and humerus head (1). A majority of the lesions were osteolytic (62.5%) with a median time of diagnosis of SM from initial diagnosis being 1.25 months (range 0-33). Bone pain was observed as the initial symptom in 5 pts (32%), 1 pt (6.2%) had a pathological fracture. The mOS for patients with SM was 6.5 months (range 0-38) when compared to 8 months (range 0-147) without SM.The mOS for pts treated with gemcitabine based regimen was 5.75 months (range 2.5-14), and patients who received multiple lines of therapy including gemcitabine and 5-FU based regimens was 15 months (range 5-38). Survival from onset of skeletal metastases ranged from 0-14 months (mOS: 4 months). Conclusions: More effective systemic therapies which improve mOS are likely to result in increased incidence of SM. The most common sites observed were the thoracic and lumbar vertebrae and pathological fractures in these sites can be catastrophic. Therefore careful evaluation of skeletal signs and symptoms, early detection and intervention will be important to prevent morbidity and mortality from pathological fractures.

Early colorectal cancer detection on routine CT to improve patient's 5-year survival

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Background: Prognosis of colorectal cancer (CRC) is greatly influenced by stage at diagnosis. Early colorectal cancer can be subtle on CT scans showing only mild wall thickening, small polyps, or subtle lymph nodes. Identifying these lesions on CT performed for nonspecific symptoms can help identify interval CRC and improve patient outcome. The purpose of the present study is to classify missed CRC on abdominal CT by their imaging features and whether early identification can downstage CRC patients. Methods: A retrospective analysis was conducted of patients (pts) diagnosed with CRC. Data collection included age, gender, ECOG, KRAS mutation status, overall survival (OS). CT obtained prior to and at diagnosis were evaluated. Images were reviewed for multiple CT features including appearance of mass, mesenteric infiltration, abnormal draining lymph nodes, contrast enhancement relative to adjacent mucosa, and intralesional calcifications. Staging was evaluated using available CT scan and based on the TNM staging system for CRC. Results: The 41 pts with 51 prediagnostic CTs from 1/1/2012 - 12/31/2015 had mean age of 68 years (range:44-90 ) Mean ECOG status for the population was 1.46. 41% of the prediagnostic CTs had missed findings. 52 and 43 % of the missed findings were in the rectosigmoid and ascending colon respectively. Of the 15 missed masses, 9 appeared as asymmetric wall thickening, 3 as concentric wall thickening, and 3 as polyps. Of the 14 missed lymph node groups, 2 were excluded due to stability or nonrelated condition. The remaining lymph nodes were found in the associated draining station and averaged 3±1.2 mm in size. On average, the stage at prediagnostic CT was 3A and the diagnostic CT was 3C (p = 0.0015). Average time lapse between prediagnostic and diagnostic CT was 21 months (3-64 months). Conclusions: High percentage of CRC findings are missed on abdominal CT due to their subtle feature, with most misses in the rectosigmoid and ascending colon. A dedicated search can improve detection by specifically looking for polyps, wall thickening, and small lymph nodes in the draining station. Early detection of CRC can improve survival by lowering the stage from 3C to 3A, thus providing 36% improvement in 5-year survival.

Synchronous primary adenocarcinoma of the lung and pancreas: a case series and review of the literature

Aim

The frequency of pancreatic cancer in association with cancer of other organs ranges from 1 to 20%, with the most common ones being gastric, colon, thyroid and genitourinary. The presence of synchronous lung and pancreatic cancers is extremely rare.

Case series

Two patients with extensive smoking history and variable presentations were found to have simultaneous lung and pancreatic masses both lesions being different histologically and on immunohistochemical staining. After individualized treatment plans, the first patient remains free of disease and the second patient is being treated with a palliative intent.

Conclusion

The early recognition and treatment is important as there exists a significant survival difference in patients who have synchronous primaries as opposed to those with metastatic pancreatic adenocarcinoma.

Tumor cell-free DNA copy number instability compared to CA19-9 as an early predictor of response to systemic therapy in pancreatic ductal adenocarcinoma (PDAC)

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Background: Humoral tumor markers are used clinically for real-time assessment of therapeutic efficacy. In pancreatic ductal adenocarcinoma (PDAC) the predominant marker is CA19-9, which is not expressed by 10 to 30% of patients depending on race. We compared plasma cell-free DNA (cfDNA) copy number based assay with changes in serum CA19-9 levels and radiological responses to predict responses to systemic therapy. Methods: In a laboratory blinded, prospective multicenter pilot study, 40 non-resectable PDAC patients, treated with (m)FOLFIRINOX, CAPIRI, or gemcitabine +/- nab-paclitaxel) are currently enrolled. CA19-9 was determined in the local center’s laboratory. Tumor cfDNA was measured with a copy-number instability (CNI) scoring assay, determined by next generation sequencing in a centralized laboratory. The CNI score assesses the amount of cfDNA with somatic macro-alterations originating from malignant neoplasms. The difference of the values before commencing therapy (baseline) and prior to cycle 2 (either rising or falling) was calculated as a predictor of standardized radiological evaluation of chemotherapeutic efficacy. Results: 37 patients (3 drop-outs) had data for baseline and cycle 2, of which CA19-9 was elevated and evaluable in 29 patients. The direction from baseline to cycle 2 of CA19-9 and CNI scores were in agreement in 18/29 patients. 9 of 11 cases with discordant CNI score and CA19-9 had treatment response data, and CNI correlated with 7/9 (78%); in contrast 7/9 had rising CA19-9, when response was stable disease or better (22% concordance). In the 27 patients with available imaging, CNI predicted better (n = 18) than CA19-9 (n = 10) (p = 0.03 Fisher’s exact). Conclusions: This comparative study on cfDNA versus CA19-9 suggest that cfDNA CNI quantitation is a potentially more reliable blood based marker for early real-time assessment of efficacy in systemic PDAC therapy than CA19-9, compared to standard of care imaging. The better prediction after the first cycle might be due to the very short in vivo half-life of cfDNA ( < 1hr) compared to about one week for CA19-9. These results justify a larger prospective validation trial.

BBI608-503-103HCC: A phase Ib/II clinical study of napabucasin (BBI608) in combination with sorafenib or amcasertib (BBI503) in combination with sorafenib (Sor) in adult patients with hepatocellular carcinoma (HCC)

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Background: Napabucasin, a first-in-class cancer stemness inhibitor in clinical development, suppresses cancer stemness by targeting STAT3-driven gene transcription. Amcasertib targets multiple serine threonine stemness kinases and inhibits Nanog and other cancer stemness pathways. Preclinically, potent and broad-spectrum anti-cancer activity was observed in vitro and in vivo, alone and in combination with sorafenib. Methods: A phase Ib/II open-label, multi-center study in adult patients with advanced HCC who have not received prior systemic chemotherapy was performed to determine the safety, tolerability, and recommended Phase II dose (RP2D) ,according to the criteria for DLT and for dose-escalation of Napabucasin (Arm 1), administered at 160 mg BID (dose level I) and at 240 mg BID (dose level II) in combination with sorafenib and of Amcasertib (Arm 2), administered at 100 mg QD (dose level I) and at 200 mg QD (dose level II) in combination with sorafenib. Results: 20 pts were enrolled, 10 in Arm 1 and 10 in Arm 2. 12 patients were evaluable for DLT determination; 2 pts d/c prior to starting protocol treatment; 11 pts received evaluation by RECIST, 6 pts in Arm 1 and 5 pts in Arm 2. The safety profile was consistent with that of each agent as monotherapy and most common AEs were attributed to (Sor) and included rash, PPE, grade 1/2 diarrhea, nausea, abdominal cramps, and vomiting. No signs of drug-drug interactions were observed in pharmacokinetics. Among all patients who received RECIST evaluation, Disease Control Rate (DCR=CR+PR+SD) for Arm 1 was 100% (6/6pts) and 100% (5/5pts) for Arm 2. DCR in ITT Arm 1 population was 67% and 50% in Arm 2. Median OS is not yet reached. Conclusions: In this phase Ib study, RP2D were determined for napabucasin and amcasertib to be safely combined with sorafenib at full dose, showing encouraging anti-tumor activity in patients with HCC who have not received prior systemic chemotherapy. A randomized phase II is schedule to start. Clinical trial information: NCD02279719. [Table: see text]

Platinum-Gemcitabine-Avastin (PGA) for platinum-resistant/refractory ovarian cancer

OBJECTIVES

Synergism between gemcitabine and platinum is known clinically. Bevacizumab in combination with single-agent chemotherapy has demonstrated significant clinical activity in platinum-resistant recurrent ovarian cancer in AURELIA study. However, the efficacy of platinum-gemcitabine-bevacizumab (PGA) has not been investigated in the platinum-resistant population.

MATERIALS AND METHODS

A retrospective chart review was conducted in all patients with platinum-resistant/refractory ovarian cancer treated with triplet combination therapy containing a platinum agent, gemcitabine, and bevacizumab between July 2011 and December 2013.

RESULTS

In total, 13 patients met the selection criteria, including ten patients with resistant disease (10/13, 77%) and three patients with refractory disease (3/13, 23%). Most of the patients were heavily pre-treated, having received over three lines of prior chemotherapy regimens on average (range 1-11). All patients had previously received taxane therapy; four patients received gemcitabine, seven patients failed combination regimens including bevacizumab, and three patients progressed on chemotherapy including both gemcitabine and bevacizumab. Ten patients responded biochemically to the therapy (defined by CA-125 declined by at least 50%). Of ten responders, one patient achieved CR for 24 months (8%), six patients achieved PR for 6.8 months (46%), three had stable disease for 6.7 months (23%), and three patients had PD (23%) by RECIST 1.1 criteria. The regimen was well-tolerated. One patient (8%) developed grade 3 neutropenia and neutropenic fever, requiring hospitalization, two patients developed grade 3 thrombocytopenia, two patients (15%) developed thrombosis in internal jugular vein, requiring discontinuation of bevacizumab, one patient (8%) experienced skin ulcer, and two patients developed thrombosis in internal jugular vein, requiring discontinuation of bevacizumab.

CONCLUSIONS

Combination of PGA appears to be safe and very active against platinum-resistant/refractory ovarian cancer and merits further evaluation prospectively. A randomized phase II study (NCTO 1936974) is currently under way to confirm this important finding.

Radiological markers of treatment responsiveness in patients (pts) with metastatic pancreatic ductal adenocarcinomas (mPDAC) receiving systemic chemotherapy

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Background: mPDAC is a deadly disease with dismal survival. Newer systemic therapies including gemcitabine/nab-paclitaxel (GA) and FOLFIRINOX (FF) have resulted in modest increases in median overall survival(mOS). Currently, no good predictors exist to prioritize the use of one regimen over the other. We investigated imaging patterns in patients receiving these two regimens. Methods: A single institution retrospective analysis of pts with mPDAC receiving either GA or FF as the front-line therapy between Jan 2012 - Dec 2014 was conducted. Data included demographics and systemic therapy.Baseline CT evaluated six imaging features; lung metastases, liver metastases, peripancreatic adenopathy, retroperitoneal adenopathy, mesentery/omentum infiltration and ascites. Statistical analysis included Kaplan Meier survival analysis with Chi-square test to compare imaging features that predict mOS or median response duration (mRD). Results: N = 27 pts; median age:GA-66 years( range: 52-76), FF-55 years (range: 40-67); 13 pts (48 %) were women and 24 pts had an ECOG performance status of ≤ 1. 18 pts received GA and 9 received FF. mOS with GA = 6.1 months(m) ( range: 1.9-15.7) and FF = 9.9 m (range: 2.5-24.1). 5/18 (28%) of the GA group and 7/9(78%) of the FF group received subsequent therapies. The presence of peripancreatic adenopathy in GA pts correlated with prolonged mRD (2.2 vs. 0.6 m; p < 0.001) without statistical difference in mOS (8.5 vs. 2.9 m; p = 0.4). In pts receiving FF the absence of hepatic metastasis resulted in a significant mRD (2.3 vs. 0.9 m; p = 0.01) and mOS (7.9 vs. 1.9 m; p = 0.04). The remainder of the radiological features did not show any statistically significant difference. Conclusions: In patients with mPDAC receiving GA or FF in front-line therapy; we observed that metastasis to the liver predicts worse outcome with FF than GA. Interestingly, peripancreatic lymphadenopathy was predictive of longer mRD for GA pts, without difference in mOS. Our pilot data demonstrates the potential of using CT imaging features to predict likelihood of response to different chemotherapy regimens. A larger study is needed to confirm these findings.

Incidence and clinical significance of ESR1 mutations in heavily pretreated metastatic breast cancer patients

BACKGROUND

ESR1 mutation has recently emerged as one of the important mechanisms involved in endocrine resistance. The incidence and clinical implication of ESR1 mutation has not been well evaluated in heavily pretreated breast cancer patients.

METHODS

We conducted a retrospective review of advanced breast cancer patients with tumors who underwent next-generation sequencing genomic profiling using Foundation One test at Cancer Treatment Centers of America(®) regional hospitals between November 2012 and November 2014.

RESULTS

We identified a total of 341 patients including 217 (59%) estrogen receptor (ER)+, 177 (48%) progesterone receptor (PR)+, 30 (8%) hormone receptor+/HER2 positive, and 119 (32%) triple negative patients. ESR1 mutation was noted in 27/222 (12.1%) ER+ or PR+ breast cancer patients. All ER+ patients received at least one line of an aromatase inhibitor. All 28 patients were found to harbor ESR1 mutations affecting ligand-binding domain with the most common mutations affecting Y537 (17/28, 60.7%) and D538 (9/28, 32.1%). In this cohort, 19 (67.9%) patients carried three or more, seven (25%) patients had one or two additional genomic alterations and one (3.6%) patient had an ESR1 mutation only. Of 28 patients, three patients were treated with fulvestrant immediately before and two patients were treated after next-generation sequencing testing; only one patient achieved stable disease for 8 months and the other four patients had progression of disease. In all, 3/3 (100%) patients before testing and 2/4 (50%) after testing treated with exemestane and everolimus achieved stable disease for at least 6 months.

CONCLUSION

ESR1 mutation was found in 12.1% of a large cohort of advanced breast cancer patients. Exemestane in combination with everolimus might be a reasonable option. Prospective studies are warranted to validate these findings.

Signet-Ring Cell Carcinoma of the Colon: A Case Report and Review of the Literature

Background

Colorectal adenocarcinoma (CRC) is the third leading cause of death in the United States. One of the histologic subtypes of CRC is signet-ring cell carcinoma (SRCC), which has a distinct molecular and tumor biology from that of adenocarcinoma. Primary SRCC diagnosed at an early stage is very rare as most cases are detected at an advanced stage. Therefore, overall prognosis of SRCC is poor.

Case Presentation

A 36-year-old female presented to her primary care physician with new-onset progressive right lower quadrant pain without any significant past medical or family history. Computed tomography scan of the abdomen and pelvis with contrast showed a 4.9 × 3.5 × 3.1 cm, lobulated, septated cystic mass arising from the cecum. The mass demonstrated wall enhancement and contained focal areas of coarse calcification. There was nodal involvement either locally or distally. The patient underwent right hemicolectomy, and pathology revealed a high-grade mucinous carcinoma with signet-ring cell variant invading through the muscularis propria and into the subserosal adipose tissue. The margins were negative for tumor, and no lymphovascular or perineural invasion was noted. None of the 14 resected pericolonic lymph nodes was positive for malignancy. Hence, she was staged as pT3, pN0, pMx-stage IIA. The appendix was not involved. Microsatellite instability testing showed the preservation of MLH1, PMS2, MSH2 and MSH6 proteins by IHC and PCR. Carcinoembryonic antigen level was within normal limits. Due to the patient's young age, aggressive histology and microsatellite-stable status, adjuvant fluropyrimidine (5-FU)-based therapy with the single agent capecitabine was initiated. The patient completed 6 months of adjuvant therapy and has been disease free for approximately 18 months.

Conclusion

Primary SRCC of the cecum is a rare disease. Given the poor prognosis of these patients, early-stage disease with microsatellite-stable patients should be considered for adjuvant 5-FU-based therapy in an attempt to prevent recurrence.

Albumin-bound paclitaxel in solid tumors: clinical development and future directions

Albumin-bound paclitaxel (nab-paclitaxel) is a solvent-free formulation of paclitaxel that was initially developed more than a decade ago to overcome toxicities associated with the solvents used in the formulation of standard paclitaxel and to potentially improve efficacy. Nab-paclitaxel has demonstrated an advantage over solvent-based paclitaxel by being able to deliver a higher dose of paclitaxel to tumors and decrease the incidence of serious toxicities, including severe allergic reactions. To date, nab-paclitaxel has been indicated for the treatment of three solid tumors in the USA. It was first approved for the treatment of metastatic breast cancer in 2005, followed by locally advanced or metastatic non-small-cell lung cancer in 2012, and most recently for metastatic pancreatic cancer in 2013. Nab-paclitaxel is also under investigation for the treatment of a number of other solid tumors. This review highlights key clinical efficacy and safety outcomes of nab-paclitaxel in the solid tumors for which it is currently indicated, discusses ongoing trials that may provide new data for the expansion of nab-paclitaxel's indications into other solid tumors, and provides a clinical perspective on the use of nab-paclitaxel in practice.

Metastatic Breast Cancer with Extensive Osseous Metastasis Presenting with Symptomatic Immune Thrombocytopenic Purpura and Anemia: A Case Report and Review of the Literature

BACKGROUND

Immune thrombocytopenic purpura (ITP) is a rare acquired bleeding disorder with an estimated incidence of 1 in 10,000 people in the general population. The association of ITP with breast cancer is an even rarer entity with very limited reports in the English literature.

CASE PRESENTATION

We report a case of a 51-year-old female with no significant past medical history who presented with sudden onset of malaise, syncope, gingival bleed and epistaxis. She was found to have severe thrombocytopenia (platelet count 6,000/μl) and anemia (hemoglobin 7.2 g/dl). Her workup led to the diagnosis of metastatic ductal breast cancer with extensive bone metastasis. Bone marrow biopsy demonstrated myelophthisis which was initially thought to be consistent with her presentation of thrombocytopenia and anemia. Therefore, the patient was started on hormonal therapy for the treatment of her metastatic breast cancer. After 3 months of therapy, she did not improve and developed severe mucosal bleeding. Her clinical presentation was suspicious for ITP and immune-mediated anemia, and hence she was started on steroids and intravenous immunoglobulin. The patient had a dramatic response to therapy with normalization of her platelet count and hemoglobin within 2 weeks.

CONCLUSION

To our knowledge, this is the first reported case of metastatic breast cancer presenting with symptomatic ITP and anemia, and both symptoms are postulated to be immune-mediated.

Genomic change index (GCI) and liquid biopsies in predicting and monitoring response to therapy in advanced pancreatic ductal adenocarcinoma (PDAC)

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Background: Advanced PDAC is a lethal disease with dismal 5 year survival. The current modalities for monitoring therapy response using serum (CA) 19-9 levels have poor specificity and radiological responses have long lag times. Tests for rapid and accurate clinical assessment are needed for early decision making. Methods: 5 patients (pts) with locally advanced unresectable or metastatic PDAC were treated with gemcitabine and nab-Paclitaxel on a bi-weekly schedule. Tumor tissue was collected at baseline and plasma was collected at each cycle (3 time points). Tumor tissue and leukocyte DNA was used to prepare shotgun sequencing libraries and PCR-based enrichment of 124 genes for paired-end high-throughput sequencing. Copy-number variations were called by comparing tumor vs. leukocytes read counts in genomic windows. Algorithms were used to quantify a Genomic Change Index (GCI) from selected variations of the cancer genome. Somatic mutations were quantified in cell-free plasma DNA (cfDNA) of 3 pts using droplet digital PCR (ddPCR) as a function of treatment. Results: Of the 5 pts evaluated, the lowest GCI’s (<10) was present in a non-responding (NR) pt receiving chemotherapy. 4 pts with varying degrees of clinical, biochemical and radiological (ranging from partial (PR) to stable disease (SD) to complete (CR)] responses, showed elevated GCIs (≥15). Detected tumor mutations were followed by liquid biopsies. In a patient with SD, mutKRAS and mutTP53 cfDNA copies of 20-80 per mL plasma (cp/mL) did not significantly change over time. In a patient with CR and >70% decrease in CA19-9; no copies of mutKRAS and 4-10 cp/mL mutTP53 were detected at the 3 time points measured. In a pt with PR and rising CA19-9, there was also an increase in mutKRAS and mutTP53 cp/mL. Conclusions: 1.) Our pilot study indicates that GCI may be similarly predictive of PDAC response to therapy as we have previously reported with head/neck and colorectal carcinomas. 2.) ddPCR has sufficient sensitivity to monitor tumor mutations in the plasma of PDAC pts and could provide a specific biomarker to monitor response. Both tests are currently being validated with longer follow up and larger number of patients.

Effect of renin-angiotensin system (RAS) inhibition on survival in advanced ductal adenocarcinoma (PDAC)

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Background: Advanced PDAC portends a poor survival due to several factors including development of resistance to therapies via tumor-stromal interactions. In preclinical studies, RAS inhibition has been implicated in PDAC development due to its anti-inflammatory effect by reducing pancreatic inflammation and fibrosis via suppressed activation of pancreatic stellate cells. Methods: A retrospective analysis was conducted at two institutions in North America of patients (pts) with advanced PDAC receiving palliative chemotherapy. Data collection included age, gender, ECOG, prescription for an angiotensin I-converting enzyme inhibitors (ACEIs) and/or angiotensin II type-1 receptor blockers (ARBs), and overall survival (OS). Statistical analysis included Kaplan Meier survival analysis along with the log-rank test to compare treatment strata. Additionally, multivariate analyses were performed using a Cox proportional hazard model. Results: The 403 pts included had a median age of 61 years (range: 25-86 yrs); 176(43%) were women and 329 (>80%) had an ECOG performance status of 0 or 1. A majority of patients received combination therapy that was either gemcitabine or 5-flurouracil based. 57 (14%) received ACEIs and 25(6.2%) received ARBs. There was no statistically significant difference in median OS between those prescribed ACEI or ARB and those who were not (13.7 vs. 14.2 months; p=0.432). Subgroup analysis of ACEI vs. no ACEI or ARBs vs. no ARBs was similar (ACEI =13.8 vs. 14.2 months (p=0.741) and ARB=13.7 vs. 14.2 months (p=0.405). In addition, ACEI vs. ARB showed similar results 13.8 months (ACEIs) vs. 13.7 months (ARBs) (p=0.687). Conclusions: Our study did not demonstrate a statistically significant difference in OS between advanced PDAC patients in North America that were prescribed ACEI, ARB, or to those who were not. Compliance with taking prescribed ACEI or ARB medications could not be determined. A prospective phase 2 study in a Japanese population using the combination of gemcitabine and candesartan (an ARB) did not demonstrate a survival benefit with the combination. Based on these clinical evaluations, use of ACEI or ARB to take advantage of blocking RAS in advanced PDAC cannot be supported.

Sarcopenia as a predictor of mortality in advanced pancreatic cancer

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Background: Pancreatic cancer (PC) patients have multiple risk factors for malnutrition including digestive enzyme deficiency, gastric outlet obstruction and post prandial abdominal pain. In order to assess prognosis and triage patients at risk for malnutrition, accurate nutrition assessment is crucial. Overweight (Ow) or obese (Ob) patients pose a particular challenge and weight status should not be the only determining nutritional assessment tool. Sarcopenia (Sp) is defined as muscle mass (MM) two standard deviations below the healthy adult mean. It has been demonstrated in multiple studies to be a more accurate indicator of nutritional status. Sp is associated with poor clinical outcomes and lower survival in other conditions such as cirrhosis. Radiologic assessment of MM can be obtained reliably from computed tomography (CT) scans. Methods: All patients with advanced PC who had baseline CT scans were included in this study. MM assessment was performed using an automated software (SliceOmatic, Tomovision, Montreal) and the skeletal muscle index(SMI) was calculated at level of the 3rd lumbar (L3) vertebrae. Multiple patient characteristics were assessed including demographics, weight, body mass index (BMI), cancer stage, treatment received and survival. Sp was defined as an L3 SMI of less than 38.5 in women and 52.4 in men. Survival analysis was performed using SAS software and Log-rank and Wilcoxon statistics. Results: 167 patients, 49% female, 62% with sarcopenia (S+), 44% Ow/Ob (O+) and 14% sarcopenic and Ow/Ob (S+O+). Patients received a variety of treatments including surgery, chemotherapy and radiation. There was a trend towards lower survival in S+O+ patients while patients who were S-O+ survived the longest. Median survival in months was 6.2 for S+O+, 7.1 for S+O-, 7.8 for S-O- and 10 for S-O+. Conclusions: Patients with sarcopenia appear to have decreased survival especially if overweight/obese. This suggests that overweight/obese pancreatic cancer patients with sarcopenia may derive the most benefit from aggressive nutritional interventions. Well powered prospective studies are needed to confirm this observation and study the effects of aggressive nutritional interventions in this subgroup of patients.

Next-generation sequencing (NGS) to identify potential therapeutic targets in advanced pancreatic cancer

357

Background: Even with the advent of newer systemic therapies; long term survival in advanced PDAC is dismal. Hence there is an urgent need to use technologies such as NGS to identify potential therapeutic targets. Methods: A retrospective analysis was performed of all advanced PDAC patients (pts) evaluated with NGS through Foundation One (Foundation Medicine Inc., MA). DNA was extracted from biopsy specimens and sequencing was performed of 315 cancer-related genes plus select introns. Statistical analysis including Kaplan Meier survival analysis along with the log-rank test was used to compare the differences between groups. Results: 53pts were analyzed between Nov 2012 - Sep 2014; 25 (47%) were females; median age was 59 yrs (range: 33-77). 178 genomic alterations (GAs) were identified in 52 pts (average 3.43 GAs/pt). The GAs included mutations 140 (78%), amplifications 25 (14%), loss/deletions 13 (7%) and 1 pt had no GAs. Most frequent GAs and associated survival are listed in Table 1. There was no statistically significant difference in median overall survival (mOS) between the groups with or without KRAS (22.1 vs. 21 months; p=0.95) and with or without TP53 (21 vs. 23.4 months; p=0.76). 6/52 pts (12%) who had received at least 3 prior lines of therapy (range 3-4) and had an ECOG performance status <2; were treated off label with trametinib. The median PFS on the last therapy prior was 5 months (range 1.6-7). On trametinib, the median PFS was 1.9 months (range 1.1-7.1) with mOS of 5.1 months. Conclusions: Our data demonstrate that there are a range of GAs that are eligible for investigational targeted therapies. Secondly, the choice of agents (eg. Trametinib - targets downstream RAS effectors ) based on individual genomic profile can be considered when an appropriate clinical trial is not available or inaccessible even in heavily pretreated patients with a good performance status. Tumor profiling should be utilized in drug development to personalize treatment options in patients with advanced PDAC. [Table: see text]

The association of metabolic syndrome with triple-negative breast cancer

Metabolic syndrome, a conglomerate of obesity, insulin resistance, dyslipidemia, and hypertension has been linked with an increased risk of breast cancer. We investigated the possible association of highly aggressive triple-negative breast cancer and the metabolic syndrome. Information on metabolic syndrome components and tumor characteristics were reviewed in a cohort of 176 patients (including 86 triple-negatives). Retrospective comparison was performed using Pearson Chi-square test or Student's t test for data analysis. A statistically significant association of triple-negative breast cancer with the metabolic syndrome was observed. In accordance with the NCEP (National Cholesterol Education Program) definition, 58.1% of triple-negative patients had metabolic syndrome compared to only 36.7% of non-triple-negative patients (P = 0.004). Consistently, by the AACE (American Association of Clinical Endocrinologists) criteria, 52.3% of triple-negative patients had metabolic syndrome as compared to 34.4% of non-triple-negative patients (P = 0.017). Blood glucose, triglyceride, and HDL levels but not hypertension or BMI (body mass index) showed significant independent association with triple-negative breast cancer. Additionally, triple-negative tumors displayed a significantly higher histological grade and relative paucity of ductal carcinoma in situ (DCIS) when compared to the non-triple-negative tumors (P < 0.001). Our study suggests that metabolic syndrome is significantly more prevalent in triple-negative breast cancer patients as opposed to non-triple-negative patients. Furthermore, triple-negative breast cancer showed a significantly higher histological grade and a relative absence of DCIS. Whether the presence of metabolic syndrome preferentially increases the risk of developing triple-negative-breast cancer remains to be elucidated with future prospective studies.

Complete remission of metastatic carcinoma of the prostate with bicalutamide withdrawal

An 83-year-old man was diagnosed with stage 4 prostate cancer with a Gleason score of 7 (3+4). His initial prostate-specific antigen (PSA) level was 965 ng/dL, and he demonstrated extensive metastatic disease of the thoracic spine. After an initial response to monthly leuprolide injections, his PSA level began to increase and bicalutamide was added. An initial decrease in his PSA level was observed; however, the level gradually rose to 212 ng/dL and bicalutamide was discontinued. Three months later, his PSA level was <0.05 ng/dL and has remained <1 ng/dL for the past 27 months. Bicalutamide withdrawal usually leads to transient remission, with PSA level dropping to approximately 50% of the initial level. The duration of the remission is usually limited to approximately 6 months. However, the sustained response that was observed in our patient suggests that a trial of androgen withdrawal, even in the setting of rising PSA levels, might be reasonable before initiating more toxic therapies.

Primary malignant melanoma of the lung: a case report and review of the literature

Melanomas of the respiratory tract are usually metastatic in origin, and finding a primary melanoma is very rare. We report the case of a 60-year-old man who presented with a 2-month history of cough with associated weight loss. The histopathologic findings were consistent with those of a melanoma. Before considering the diagnosis of primary melanoma of the lung, an extensive diagnostic workup was done to rule out metastasis from an occult primary tumor. In addition, previously reported cases of primary lung melanoma were reviewed, and the established criteria for determining the primary site were applied. Because the precise etiology has not yet been elucidated, the possible mechanism is discussed.

The Serum Glycoprotein Fetuin-A Promotes Lewis Lung Carcinoma Tumorigenesis via Adhesive-Dependent and Adhesive-Independent Mechanisms

Fetuin-A is a serum glycoprotein in the cystatin family associated with the regulation of soft tissue calcification. We tested the role of systemic fetuin in tumor cell growth and metastasis by injecting Lewis lung carcinoma (LLC) cells into fetuin-A null and their wild-type (WT) littermate control C57BL/6 mice via the tail vein, s.c., and intrasplenic routes. In the experimental metastasis assay, the lungs of the WT mice were filled with metastatic nodules, whereas the lungs of the fetuin-A null mutant mice were virtually free of colonies at the end of 2 weeks. Lung colonization responded to the levels of serum fetuin-A in a dose-dependent manner, as observed by the formation of half as many colonies in mice heterozygous for the fetuin-A locus compared with homozygous WT mice and restoration of lung colonization by the administration of purified fetuin-A to fetuin-A-null mice. Serum fetuin-A also influenced the growth of LLC cells injected s.c.: fetuin-A-null mice developed small s.c. tumors only after a substantial delay. Similarly, intrasplenic injection of LLC cells resulted in rapid colonization of the liver with metastasis to the lungs within 2 weeks in the WT but not fetuin-A null mice. To examine the mechanism by which fetuin-A influences LLC colonization and growth, we showed that LLC tumor cells adhere to fetuin-A in a Ca2+-dependent fashion, resulting in growth of the tumor cells. These studies support the role of fetuin-A as a major growth promoter in serum that can influence tumor establishment and growth.

The serum glycoprotein fetuin-A promotes Lewis lung carcinoma tumorigenesis via adhesive-dependent and adhesive-independent mechanisms

Fetuin-A is a serum glycoprotein in the cystatin family associated with the regulation of soft tissue calcification. We tested the role of systemic fetuin in tumor cell growth and metastasis by injecting Lewis lung carcinoma (LLC) cells into fetuin-A null and their wild-type (WT) littermate control C57BL/6 mice via the tail vein, s.c., and intrasplenic routes. In the experimental metastasis assay, the lungs of the WT mice were filled with metastatic nodules, whereas the lungs of the fetuin-A null mutant mice were virtually free of colonies at the end of 2 weeks. Lung colonization responded to the levels of serum fetuin-A in a dose-dependent manner, as observed by the formation of half as many colonies in mice heterozygous for the fetuin-A locus compared with homozygous WT mice and restoration of lung colonization by the administration of purified fetuin-A to fetuin-A-null mice. Serum fetuin-A also influenced the growth of LLC cells injected s.c.: fetuin-A-null mice developed small s.c. tumors only after a substantial delay. Similarly, intrasplenic injection of LLC cells resulted in rapid colonization of the liver with metastasis to the lungs within 2 weeks in the WT but not fetuin-A null mice. To examine the mechanism by which fetuin-A influences LLC colonization and growth, we showed that LLC tumor cells adhere to fetuin-A in a Ca(2+)-dependent fashion, resulting in growth of the tumor cells. These studies support the role of fetuin-A as a major growth promoter in serum that can influence tumor establishment and growth.

Annexins expressed on the cell surface serve as receptors for adhesion to immobilized fetuin-A

Fetuin-A is a major constituent of the fetal bovine serum used extensively in cell culture media. We hereby present data demonstrating that breast carcinoma cells can adhere to immobilized fetuin-A in a calcium-dependent fashion. Interestingly, the cells can also divide and attain confluency under these conditions. Using a proteomic approach, we have identified annexin-II and -VI as the putative cell surface receptors for fetuin-A in the presence of Ca2+ ions. Biotinylation of cell surface proteins followed by immunoprecipitation revealed that annexin-VI was expressed on the extracytoplasmic surface of the cell membranes. Finally, to demonstrate that annexin-II and -VI were the adhesive receptors for fetuin-A, siRNA knockdown of expression of the annexins significantly reduced the calcium-mediated adhesion. Interestingly, we demonstrated that the tumor cells could also adhere to immobilized fetuin-A in the presence of magnesium ions, and that this adhesion was most likely mediated by integrins because neutralizing antibodies against beta1 integrins substantially reduced the adhesion. Our studies suggest that the expression of annexin-II and -VI and possibly other members of the family mediate novel adhesion and signaling mechanisms in tumor cells.