Impact of Institutional Universal Microsatellite-Instability (MSI) Reflex Testing on Molecular Profiling Differences Between Younger and Older Patients with Colorectal Cancer

INTRODUCTION

DNA mismatch repair deficient (dMMR) or microsatellite instability-high (MSI-H) colorectal cancer (CRC) is found in about 15% of early-stage diseases and 5% of metastatic diseases. We reviewed a large, single-institutional database after implementation of universal reflex dMMR/MSI-H testing in CRC to compare profiles of younger (≤50) and older (>50) patients.

PATIENTS AND METHODS

Between 2009 and 2017, all patients diagnosed with CRC at the University of Florida underwent reflex somatic tumor testing for dMMR by immunohistochemistry (MLH1, PMS2, MSH2, MSH6), MSI by PCR, and Next-Generation Sequencing. Statistical analysis was conducted with 2-sample comparison tests and logistic regression models.

RESULTS

There were 375 patients included in the final analysis. Patients were grouped as younger (ages ≤50 years-old; n = 80) or older (>50 years-old; n = 295). Compared to tumors from older patients, tumors from younger patients were less likely to be dMMR/MSI-H (12.5% vs. 21.4%, P = .013) and less likely to have a BRAF mutation (1.5% vs. 16.1%, P = .002). BRAF mutation status was highly associated with MMR status; BRAF-mutated tumors were 29.7 times more likely than BRAF-WT tumors to be dMMR/MSI-H (P = < .001, 95% CI 11.3-78.3).

CONCLUSIONS

Tumors of younger patients were less likely than tumors of older patients to have a dMMR/MSI-H or BRAF mutation. Universal MMR/MSI testing in our dataset identified a relatively large population of older patients with sporadic CRC who were eligible for immunotherapy.

Extremely delayed-onset post-transplant lymphoproliferative disorder in a renal transplant patient

Post-transplant lymphoproliferative disorder (PTLD) is a rare condition that occurs in patients who have undergone solid organ transplantation. Symptoms at presentation depend on the organs involved. PTLD most commonly occurs in the first year after transplant (early onset) or around 5 years after transplant (late onset). Herein, we report a rare presentation of central nervous system PTLD in an adult who presented with seizures 17 years after renal transplantation. After extensive infectious and transplant-related workup, brain biopsy confirmed the diagnosis of PTLD. The patient was treated with rituximab and high-dose methotrexate. Eighteen months later, the patient had no signs of recurrence. Very late-onset (>10 years) PTLD is rare, but is likely to become more common with more long-term survivors of solid organ transplant. Data are limited but show that the factors associated with very late-onset PTLD are different from early or late-onset PTLD.

Results of a phase II trial of the PARP inhibitor, niraparib, in BAP1 and other DNA damage response pathway deficient neoplasms

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Background: BRCA1-Associated Protein 1 (BAP1) acts as a tumor suppressor and critical regulator of the cell cycle and DNA damage response (DDR). PARP inhibitors (PARPi) demonstrate synthetic lethality in BAP1 mutant (mBAP1) preclinical models, independent of underlying germline BRCA status. mBAP1 leads to a loss of functional protein in several solid tumors. This study aimed to explore the clinical activity of niraparib in patients (pts) with advanced tumors likely to harbor mBAP1. Methods: Eligible adult pts with measurable metastatic solid tumors having exhausted approved therapies, adequate organ function, and ECOG PS 0-1 were assigned to Cohort A (histology-specific): tumors likely to harbor mBAP1 (i.e., cholangiocarcinoma, uveal melanoma, mesothelioma, or clear cell renal cell carcinoma) with tissue available for mBAP1 confirmation; or Cohort B (histology-agnostic): tumors with other known non-BRCA confirmed DDR mutations. Known BRCA1 or 2 mutations or prior PARPi exposure were excluded. All pts received niraparib 200-300mg daily, depending on weight and/or platelet count. Radiographic response was assessed by RECIST v1.1 measured every 8 weeks while on treatment. The primary endpoint was ORR with secondary endpoints of PFS, OS, clinical benefit (CR+PR+SD), toxicity, and exploratory biomarker determinations. Cohort A employed Simon's optimal two-stage design to assess a 30% ORR increase (a = 0.05; power = 90%). Cohort B aimed to assess a 40% ORR increase for this molecularly selected/enriched patient population. Results: From 08/13/2018 to 12/21/2021, 37 pts enrolled from two different centers, with 32 evaluable for response (Cohort A n = 18; Cohort B n = 14). In Cohort A, best ORR was 1 PR (6%), 8 SD (44%; median 5.7 mo; range 2 - 9.4 mo), and 9 PD (50%). Cohort A was stopped at the first stage following the pre-specified Simon’s design. mBAP1 was confirmed in 7/9 pts (78%) with PR or SD but in only 2/9 (22%) in those with PD. In Cohort B, best ORR was 6 SD (43%; median 7.5 mo; range 3.3 - 8.6 mo) and 8 PD (57%). Mutations in those with SD included ATM, CHEK2, PTEN, RAD50, and ARID1A. Common grade 3/4 AEs observed were anemia (16%), thrombocytopenia (16%), nausea (11%), and vomiting (8%). There were no unexpected nor grade 5 toxicities. Conclusions: The use of niraparib was well tolerated in pts with advanced treatment refractory solid tumors but failed to meet pre-specified efficacy threshold of ORR. However, clinical benefit was identified in 78% of patients in cohort A who had a confirmed mBAP1 tumor. Further correlative analyses are ongoing and additional clinical development restricted to mBAP1 tumors may be justified. Clinical trial information: NCT03207347.

Prognostic value of CA 19-9 and carcinoembrionic antigen (CEA) in duodenal adenocarcinoma (DA): An institutional retrospective cohort study

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Background: Duodenal adenocarcinoma (DA) is a rare malignancy with poor outcomes. Tumor markers are used to assess disease response and to monitor for recurrence. Specifically, CA-19-9 and CEA have been validated for use in pancreatic cancer and colorectal cancer, respectively. However, these tumor markers have never been validated in patients with DA. We aim to assess the association of these biomarkers with clinical outcomes in patients with DA. Methods: This is a retrospective cohort study. After obtaining IRB approval (IRB202102705), we accessed the University of Florida medical records of patient treated for DA from January 1, 2006, until December 31, 2021. CA 19-9 and CEA were collected as continuous variables and were analyzed as binary variables: normal vs. high, using the maximum normal value as a cut-off (normal CA 19-9 < = 35 U/ml; CEA < = 3 ng/ml). Analysis was conducted using Kaplan Meyer curves, log-rank test and Cox proportional hazards model. Results: A total of 68 patients were included in the final analysis. Median age was 67 years and median follow-up was 22.2 months. CA 19-9 and CEA were elevated in 36.8% and 48.5% of patients, respectively. Patients with an elevated CA 19-9 had a median overall survival (OS) of 8.5 months vs. 27.4 months in patients with normal levels (HR 1.67; 95%CI 0.94–2.99; p = 0.081). Patients with an elevated CEA had a median OS of 13.4 months vs. 16.8 months in patients with normal level normal levels (HR 1.43; 95%CI 0.81–2.52; p value = 0.221). In a sensitivity analysis, a concomitant elevation of both tumoral markers was significantly associated with worsened OS (HR 1.9; 95%CI 1.05–3.06; p = 0.035). Conclusions: In patients with duodenal adenocarcinoma, elevation of both CA 19-9 and CEA was associated with a statistically significant worse overall survival. CA 19-9 level had a higher prognostic impact on OS than CEA levels. To our knowledge, this is the first study to evaluate the role of CA 19-9 and CEA in patients with DA. Further research is required for validation.[Table: see text]

A Multi-Center Retrospective Analysis Examining the Effect of Dipeptidyl Peptidase-4 Inhibitors on Progression-Free Survival in Patients With Prostate Cancer

Background

Cluster of differentiation 26/dipeptidyl peptidase-4 (DPP4) is a cell surface glycoprotein with multifaceted roles, including immune regulation, glucose metabolism, and tumorigenesis. Recent literature has identified DPP4 inhibitors to improve survival in diabetic patients with prostate cancer. DPP4 inhibitors have been proposed to play a role in prostate cancer, as DPP4 is found at higher levels in malignant prostate tissue compared to benign and correlates with PSA levels and cancer stage. In this multi-center retrospective study, we aim to define the effects of DPP4 inhibitors on progression-free survival (PFS) in diabetic patients with advanced-stage prostate cancer.

Methodology

We performed a retrospective analysis of 161 patients with diabetes and advanced-stage (III or IV) prostate cancer at the University of Florida Health Cancer Center and Moffitt Cancer Center. Our cohort included 120 patients on metformin (control group) and 41 on a DPP4 inhibitor (study group).

Results

No significant difference in progression of prostate cancer was identified between those on DPP4 inhibitors versus metformin (hazard ratio [HR]: 1.01; 95% confidence interval [CI]: 0.64-1.61; p = 0.955). Median time to progression was 3.5 years (range: 2.4-4.6 years).

Conclusions

Despite prior literature indicating survival benefit of DPP4 inhibitors in prostate cancer, our study did not identify a statistically significant improvement of PFS in diabetic patients with advanced prostate cancer. Additional analysis with larger sample sizes and prospective investigation with study of tumor microenvironment are needed to evaluate clinical impact and potential survival benefit of DPP4 inhibitors in prostate cancer.

A multicenter retrospective analysis examining the effect of dipeptidyl protease 4 (DPP4) inhibitors on progression-free survival in patients with prostate cancer

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Background: Dipeptidyl peptidase IV (DPP4), also known as Cluster of differentiation 26 (CD26) is a commonly expressed cell surface protein found in many cell types that can function as a tumor suppressor or activator, depending on the cancer type its interactions with the tumor microenvironment. DPP4 has been studied as a tumor biomarker due to its expression in various primary tumors and metastases. Recent literature established benefits of DPP4 inhibitors on progression free survival (PFS) of diabetic patients with advanced colorectal and airway cancers. In this study, we examine the effect of DPP4 inhibitors on PFS in diabetic patients (pts) with advanced-stage prostate cancer. Methods: We performed a multi-center retrospective analysis at Moffitt Cancer Center and the University of Florida of diabetic pts with advanced stage (III or IV) prostate cancer. All pts were on anti-hyperglycemic therapy and received either surgery, radiation therapy, or both for their prostate cancer. The control group included pts on metformin and a sulfonylurea, and the study group included pts on a DPP4 inhibitor and metformin. PFS was calculated for both groups, and Cox proportional hazards regression was used to determine statistical significance. Kaplan-Meier survival analysis was done to predict the effect of DPP4 inhibition and radiation therapy on PFS. Results: Our study population consisted of 161 pts, with 120 pts in the control group and 41 in the study group. No significant difference in progression of prostate cancer was found between those on DPP4 inhibitor vs. Metformin. Specifically, 24 of 41 (59%) of patients on DPP4 inhibitors progressed, while 73 of 120 (61%) of patients on Metformin had progression of prostate cancer (HR 1.01, 95% CI 0.64 to 1.61, p= 0.955). Median time to progression was 3.3 years in the DPP4 group versus 3.5 years in the Metformin group. However, radiation therapy was associated with improved PFS (HR 0.56, 95% CI 0.37 to 0.84, p= 0.0006). Conclusions: Contrary to what has been shown in pts with diabetes and advanced colorectal or airway cancers, exposure to DPP4 inhibitors did not lead to statistically significant improvement in PFS in pts with advanced stage prostate cancer. Recent data suggests that DPP4 may act as a tumor suppressor gene to the androgen receptor (AR) pathway, and that DPP4 inhibition can result in emergence of resistance to androgen deprivation therapy (ADT). Further analysis with larger sample sizes is necessary to elucidate if this is applicable to prostate cancer as a whole, or if this effect is specific to castrate-sensitive prostate cancer (CSPC) vs. castrate-resistant prostate cancer (CRPC).

Reduction of immunosuppression for post-transplant lymphoproliferative disorder (PTLD): a single-center experience of allograft survival outcomes

Post-transplant lymphoproliferative disorder (PTLD) is a well-known complication of hematopoietic stem cell transplant and solid organ transplant. While reduction in immunosuppression (RIS) is the first-line treatment for PTLD, outcomes of allograft function as a result of RIS remain understudied. In this retrospective study, we examine rates of allograft rejection and graft failure after RIS in 141 patients diagnosed with PTLD at the University of Florida. Compared to prior literature demonstrating around 32-40% rate of allograft rejection as result of RIS, our institutional analysis revealed a much lower treatment-related allograft rejection rate of 18.4%. Out of the patients who experienced acute allograft rejection, 23.1% ultimately progressed to allograft failure. Interestingly, acute allograft rejection episodes during PTLD treatment were not statistically found to impact overall survival. RIS remains an overall beneficial treatment modality of PTLD due to its low allograft rejection rate relative to treatment rate.

A Comprehensive Review of Randomized Clinical Trials Shaping the Landscape of Rectal Cancer Therapy

Colorectal carcinoma is the second leading cause of cancer-related deaths in the United States, with rectal cancer accounting for approximately one third of newly diagnosed cases. Surgery remains the cornerstone of curative therapy, with total mesorectal excision being the standard of care. Although minimally invasive procedures might be appropriate for a subset of patients with early-stage, superficial tumors, the standard of care for medically operable patients with nonmetastatic rectal cancer includes a comprehensive multimodality approach of neoadjuvant chemoradiotherapy, surgery with total mesorectal excision, and systemic chemotherapy. However, the morbidity and mortality related to both local and distant organ relapse have remained challenging. In the present review, we have discussed the trial-level evidence that has shaped the current clinical practice patterns in the treatment of curable, nonmetastatic rectal cancer. In addition, we have discussed the anticipated results of ongoing clinical trials and outlined pragmatic opportunities for future investigation to optimize the current status quo and, hopefully, provide prospective validation of novel approaches in the treatment of rectal cancer.

Post Transplant Lymphoproliferative Disorder risk factors in children: Analysis of a 23-year single-institutional experience

INTRODUCTION

PTLD is the most frequent malignancy following SOT in children and the second most common SOT complication in adults. However, factors determining outcomes in children are poorly understood due to its relative rarity.

METHODS

This study was performed at the University of Florida. Univariate and multivariate analyses were used to identify prognostic factors in pediatric patients diagnosed with PTLD.

RESULTS

We reviewed records of 54 pediatric (younger than 18 years old at diagnosis) patients diagnosed with PTLD from 1994 to 2017. The median follow-up was 28.8 months. The estimated 5-year survival rate was 87.6% (95% CI 74.3-94.2%). Univariate analysis showed that organ transplanted (specifically heart transplant), poor response to initial treatment, allograft rejection, and low Karnofsky score were statistically significant for negative prognostic factors in determining survival. Multivariate analysis determined progression in response to initial treatment and presence of allograft rejection as statistically significant prognostic factors affecting overall survival. We found no statistically significant impact of EBV serological status on PTLD prognosis.

CONCLUSIONS

Disease progression and allograft rejection were strong negative prognostic indicators in our study cohort. Close attention to graft status and development of therapies that protect the graft from rejection while bolstering anti-EBV immunity will be essential to further improving PTLD outcomes in children.

Comprehensive literature review of randomized clinical trials examining novel treatment advances in patients with colon cancer

The treatment of colon cancer has had numerous recent advances, in terms of surgical approach, adjuvant therapies, and more. In this review, the authors examine randomized clinical trials comparing open surgery to laparoscopic surgery (including total mesocolic excision), and also examine the role of robotic surgery. Novel surgical techniques including the no-touch technique, side-to-side anastomosis, suture technique, complete mesocolic excision (CME) with central vascular ligation (CVL), and natural orifice transluminal endoscopic surgery (NOTES) are outlined. The role of placing endoscopic self-expandable metal stents (SEMS) for colonic obstruction is compared and contrasted with the surgical approach, and the effect that the anti-VEGF inhibitor bevacizumab may have on this side effect profile is further explored. The role of the resection of the primary tumor in the setting of metastatic disease is examined with respect to survival benefit. Pathways of perioperative care which can accelerate post-surgical recovery, including enhanced recovery after surgery (ERAS) are examined. The role of adjuvant chemotherapy in patients with high-risk stage II and patients with stage III disease is examined, along with the role on circulating tumor DNA (ctDNA) as well as with the biologic targeted agents cetuximab and bevacizumab. Lastly, the authors detail the postoperative surveillance schedules after surgical resection with respect to survival outcomes.

Single-institution Retrospective Analysis of Prognostic Factors Influencing Very Late-onset Post-transplant Lymphoproliferative Disorder

Background Post-transplant lymphoproliferative disorder (PTLD) is a rare complication following transplant (solid organ or allogeneic) due to the proliferation of lymphoid cells in the immunosuppressed state. The incidence of PTLD follows a bimodal distribution, with high incidence immediately after transplant (early-onset PTLD), followed by a decline and then a high-incidence again five years after transplantation (late-onset PTLD). This study exclusively aims to identify prognostic factors for the subgroup of PTLD, described as very late-onset PTLD, occurring after 10 years of transplant. Methods This study was conducted at the University of Florida, with the requisite study population identified through the cancer registry. Data were collected by individual chart review and analyzed. Survival estimates and univariate and multivariate analyses were performed to measure the effects of each variable on overall survival. Results A total of 33 patients were identified, with a median age at transplant of 42.3 years, while the median age at PTLD diagnosis was 54.7 years. Median time from transplant to PTLD diagnosis was 13.3 years. Kidney (30.3%), liver (27.3%), and heart (24.2%) transplants were the most common allografts associated with very late PTLD development. The most common pathology was diffuse large B-cell lymphoma (DLBCL) in 45.5% of patients. CHOP+/-R (cyclophosphamide, doxorubicin hydrochloride (hydroxydaunorubicin), vincristine sulfate (Oncovin), prednisone, rituximab) was the most common chemo regimen used as the initial choice in 36.4% of patients. Median survival was 5.4 years. Univariate analysis showed that age at diagnosis over 65, male gender, bone marrow involvement, past medical history (PMH) of malignancy, immunosuppression regimen at PTLD diagnosis, and initial and final best response to treatment were statistically significant (p <0.05) factors associated with survival. On multivariate analysis, bone marrow involvement was significantly associated with poor survival (p=0.008). Surprisingly, performance status, Epstein-Barr virus (EBV) status, pathology type, Ann-Arbor stage, and chemotherapy regimen were not significantly associated with survival. At the end of the study, 48.5% of patients achieved complete remission and the allograft survived in 84.8%. Conclusions In this retrospective study of very-late onset PTLD, we identified factors associated with survival different from early and late PTLD. These factors should be considered during the treatment of this subgroup of PTLD patients.

Immunotherapy for Colorectal Cancer: A Review of Current and Novel Therapeutic Approaches

Colorectal cancer (CRC) remains a leading cause of cancer-related deaths in the United States. Although immunotherapy has dramatically changed the landscape of treatment for many advanced cancers, the benefit in CRC has thus far been limited to patients with microsatellite instability high (MSI-H):DNA mismatch repair-deficient (dMMR) tumors. Recent studies in the refractory CRC setting have led to US Food and Drug Administration approvals for pembrolizumab as well as nivolumab (with or without ipilimumab) for tumors harboring an MSI-H:dMMR molecular profile. Several randomized controlled trials are underway to move immunotherapy into the frontline for metastatic cancer (with or without chemotherapy) and the adjuvant setting. Awareness of these studies is critical given the relatively low incidence (approximately 3%-5%) of MSI-H:dMMR in advanced or metastatic CRC to support study completion, because the results could be potentially practice changing. The real challenge in this disease is related to demonstrating the benefit of immunotherapy for the vast majority of patients with CRC not harboring MSI-H:dMMR. Given the rapid pace of scientific changes, this article provides a narrative review regarding the current landscape of immunotherapy for CRC. Particular attention is paid to the currently available data that inform today's clinical practice along with upcoming randomized controlled trials that may soon dramatically change the treatment landscape for CRC.

National Cancer Institute (NCI) state of the science: Targeted radiosensitizers in colorectal cancer

Colorectal cancer (CRC) represents a major public health problem as the second leading cause of cancer-related mortality in the United States. Of an estimated 140,000 newly diagnosed CRC cases in 2018, roughly one-third of these patients will have a primary tumor located in the distal large bowel or rectum. The current standard-of-care approach includes curative-intent surgery, often after preoperative (neoadjuvant) radiotherapy (RT), to increase rates of tumor down-staging, clinical and pathologic response, as well as improving surgical resection quality. However, despite advancements in surgical techniques, as well as sharpened precision of dosimetry offered by contemporary RT delivery platforms, the oncology community continues to face challenges related to disease relapse. Ongoing investigations are aimed at testing novel radiosensitizing agents and treatments that might exploit the systemic antitumor effects of RT using immunotherapies. If successful, these treatments may usher in a new curative paradigm for rectal cancers, such that surgical interventions may be avoided. Importantly, this disease offers an opportunity to correlate matched paired biopsies, radiographic response, and molecular mechanisms of treatment sensitivity and resistance with clinical outcomes. Herein, the authors highlight the available evidence from preclinical models and early-phase studies, with an emphasis on promising developmental therapeutics undergoing prospective validation in larger scale clinical trials. This review by the National Cancer Institute's Radiation Research Program Colorectal Cancer Working Group provides an updated, comprehensive examination of the continuously evolving state of the science regarding radiosensitizer drug development in the curative treatment of CRC.

Investigation of Complications Following Port Insertion in a Cancer Patient Population: A Retrospective Analysis

Central venous access devices, specifically implantable ports, play an essential role in the care of oncology patients; however, complications are prevalent. This retrospective single-institutional review was performed to identify rates of complications from port placement and potential factors associated with these events. A retrospective analysis of 539 cancer patients who underwent port insertion between March 2016 and March 2017 at our institution was conducted. Data examining 18 potentially predictive factors were collected, and multivariate analysis was conducted using logistic regression and odds ratios (ORs) with standard errors to determine predictive factors. Out of 539 patients, 100 patients (19%) experienced 1 complication, and 12 patients (2%) experienced 2 or more complications. An overall lower rate of complications was seen in patients on therapeutic anticoagulation (OR: 0.17, P < .001) or on antiplatelet agents (OR: 0.47, P = .02). No patients on therapeutic anticoagulation developed venous thromboembolism (VTE; 0%). Right-sided port insertion was associated with decreased rates of infection (OR: 0.44, P = .04). Insertion as inpatient was associated with an increased risk for mechanical failure (OR: 4.60, P < .01). This analysis identified multiple predictive factors that can potentially put patients at a higher risk of experiencing complications following port insertion. Our data show lower rates of VTE for patients on anticoagulation or antiplatelet therapy. Further analysis is also necessary to determine why port insertion as an inpatient places patients at a higher risk of complications. This study highlights the risks associated with port placement and prompts the clinician to have an informed discussion with the patient weighing the risks and benefits.

Central venous access in oncology patients: A pragmatic approach to minimizing complications following port insertion

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Background: Subcutaneous venous access devices, specifically implantable ports, are vital in the care of oncology patients. Despite routine use, complications remain prevalent. This retrospective single-institutional review was performed to identify rates of complications following port placement and target areas to improve patient outcomes. Methods: Retrospective analysis of 539 cancer patients who underwent port insertion in a one-year span at University of Florida was conducted. Data examining 18 potentially predictive factors was collected, and multivariate analysis was conducted using logistic regression and odds ratios with standard errors to determine predictive factors. Results: Of 539 patients, 100 (19%) experienced a complication, and 12 (2%) experienced 2 or more complications. An overall lower rate of complications was seen in patients on therapeutic anticoagulation (OR 0.17, p < 0.001) or on antiplatelet agents (OR 0.47, p = 0.02). No patients on therapeutic anticoagulation developed VTE (0%). Right-sided port insertion was associated with decreased rates of infection (OR 0.44, p = 0.04). Insertion as inpatient was associated with increased risk for mechanical failure (OR 4.60, p < 0.01) and catheter migration (OR 4.33, p < 0.01). Conclusions: This analysis identified multiple predictive factors that can potentially put patients at higher risk of complication following port insertion. A thorough risk assessment for VTE should be done prior to port insertion, and high-risk patients (i.e. prior VTE, Khorana score > 3) should be considered for prophylactic anticoagulation. Further analysis on optimal port insertion site (right/left) and location (inpatient/outpatient) are also targets that can potentially decrease complication rates. As ports inserted while inpatient had increased risk of both mechanical failure and catheter migration, and as ports inserted on the left side had increased risk of infectious complications, a prospective quality improvement initiative coordinated between Oncology and Interventional Radiology departments as to whether insertion of right-sided ports on an outpatient basis may improve outcomes is the next step in our investigation.

Role of bevacizumab for treatment-refractory meningiomas: A systematic analysis and literature review

Background

Meningiomas are the most prevalent primary tumor of the central nervous system (CNS), and although the majority of these neoplasms are classified as benign, nearly one fourth of the lesions display an aggressive profile characterized by pleomorphic histology, high recurrence rates, and overall resistance to standard treatment. Despite the ubiquitous nature of these tumors, no adjuvant therapeutic regimen has been identified which effectively controls disease recurrence and progression after surgery and radiation, leading to a dismal prognosis in this patient population. The primary focus of this research study is, hence, to assess the recently emerging use of bevacizumab, an anti-angiogenic agent, in the treatment of meningiomas. This systematic literature review analyzes the efficacy and safety of therapeutic bevacizumab for treatment-refractory meningiomas.

Methods

A systematic PubMed search was conducted according to PRISMA guidelines to identify all relevant reports investigating the anti-angiogenic agent bevacizumab in the treatment of intracranial meningiomas. The reported parameters from pertinent retrospective reviews, prospective studies, and case studies were volumetric reduction, radiographic response, clinical stability, overall survival (OS), and progression free survival (PFS) measured at 6 and 12 months postinitiation of treatment. Complications were cataloged based on the range and severity of the therapy-related toxicities.

Results

A total of 11 articles, 5 retrospective series, 2 prospective trials, and 4 case reports, reporting on a total of 92 patients, were included in this review. The use of bevacizumab therapy for intracranial meningiomas demonstrated median overall PFS of 16.8 months (range: 6.5-22 months) and PFS-6 of 73% (range: 44%-93%).

Conclusions

Therapeutic bevacizumab, either alone or with combination chemotherapies, for select patient populations with recurrent or progressive meningiomas, offers a treatment option that confers improved overall progression-free survival. To assess OS parameters, larger randomized controlled trials assessing the use of anti-angiogenic agents for recurrent/progressive meningiomas are warranted.

Management of Malignant Bowel Obstruction Associated With GI Cancers

For many patients with GI malignancies, the seeding of the abdominal cavity with tumor cells, called peritoneal carcinomatosis, is a common mode of metastases and disease progression. Prognosis for patients with this aspect of their disease remains poor, with high disease-related morbidity and complications. Uniform and proven practices that provide optimal palliative care and quality of life for these patients are needed. The objective of this review is to critically assess the current literature regarding palliative strategies in the management of peritoneal carcinomatosis and associated symptoms in patients with advanced GI cancers. Despite encouraging results in the select population where cytoreductive surgery and intraperitoneal chemotherapy are indicated, the majority of patients who develop peritoneal carcinomatosis in the setting of GI cancers have poor prognosis, with malignant bowel obstruction representing a common terminal phase of their disease process. For all patients with peritoneal carcinomatosis, aggressive symptom control and early multimodality palliative care as further outlined should be sought.

Pericardial effusion as an atypical initial presentation of extra-gonadal nonseminomatous germ cell tumor: a case report and literature review

Extra gonadal germ cell tumors have variable clinical presentations and locations. We report a case of an extra-gonadal germ cell tumor in a 26-year-old male who presented with chest pain. Imaging revealed a large pericardial effusion with underlying mass invading the pericardium. Pericardial effusion is an extremely rare initial site of diagnosis or site of metastasis for malignancy. This case illustrates the importance of a thorough history and physical examination, broad differential diagnosis, and to keep in mind serious complications from rare presentations of disease.

Results from an institutional universal reflex testing program for MSI/MMR in colorectal cancer

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Background: In colorectal cancer (CRC), clinical guidelines and immunotherapy treatment selection requires knowledge of tumor DNA mismatch repair gene deficiencies (dMMR) or accumulation of microsatellite repeats through genomic errors (MSI-H). Tumors harboring dMMR/MSI-H are found in 15- 20% of early stage CRC while the prevalence is ~5% in metastatic disease. Reflex testing of CRC to identify these important subsets has been proposed as a system-solution to improve identification. We present a large, single-institutional database of CRC reflexively profiled for MSI/MMR status at the University of Florida (UF). Methods: Beginning in 2009, stage IV CRC underwent reflex testing for MSI/MMR status. Earlier stage CRC testing began in subsequent years. For all new CRC diagnosed at UF, concurrent testing for dMMR by IHC (MLH1, PMS2, MSH2, MSH6), MSI by PCR (Promega MSI kit) and NGS is performed with appropriate positive and negative controls. IHC protein loss is confirmed by second GI pathologist. MSI is not performed if inadequate adjacent normal tissue. We conducted a retrospective analysis of all CRC samples analyzed between 2009 and 2017. Clinical data was collected from the EMR. This study was approved by the UF IRB. Results: A total of 388 new CRC cases were reflex tested (16% Stage I, 23% Stage II, 35% Stage III, and 25% Stage IV). Median age at diagnosis was 63 yrs (range: 17-98 yrs), 51% male and 79% white. Both MMR and MSI were performed in 244 (63%) tumors with 100% concordance when concurrently tested. dMMR/MSI-H incidence (20% in overall population) decreased with stage: I/II (31%), III (18%) and IV (~9%) and was associated with BRAF V600E mut in 36/76 cases (47%). Importantly, in pts < 50 yrs, 13% of stage IV patients were dMMR/MSI-H. Conclusions: Reflex testing of MMR/MSI status in CRC is feasible with concordant results. Routine testing results in identification of dMMR/MSI-H at or higher than published rates. Notable findings include the high prevalence in those with sporadic CRC and/or younger than 50 yrs. Continued impact analysis of this approach is warranted to maximize IO therapy offering.

Post-transplant lymphoproliferative disorder (PTLD): single institutional experience of 141 patients

Background

Post-transplant lymphoproliferative disorder is a well-recognized but rare complication of hematopoietic stem cell and solid organ transplant. Due to rarity of this disease, retrospective studies from major transplant centers has been the main source to provide treatment guidelines, which are still in evolution. The sample size of this study is among one of the largest study on PTLD till date reported throughout the world.

Methods

This study was performed at University of Florida which is one of the largest transplant center in South East United States. We performed treatment and survival analysis along with univariate and multivariate analysis to identify prognostic factors.

Results

We reviewed 141 patients diagnosed with PTLD over last 22 years with median follow-up of 2.4 years. The estimated median overall survival of the entire group was 15.0 years. Sub group analysis showed that 5-year overall survival rates of pediatric population were 88% (median not reached). For adults, median OS was 5.35 years while for elderly patients it was 1.32 years. The estimated median OS of patients with monomorphic PTLD was 9.0 years while in polymorphic PTLD was 19.3 years. Univariate analysis identified gender, age at transplant and PTLD diagnosis, performance status, IPI score, allograft type, recipient EBV status, multiple acute rejections prior to PTLD diagnosis, PTLD sub-type, extra-nodal site involvement, immunosuppressive drug regimen at diagnosis, initial treatment best response were statistically significant prognostic factors (p < 0.05). On multivariate analysis, age at PTLD diagnosis, recipient EBV status, bone marrow involvement, and initial best response were statistically significant prognostic factors (p < 0.05). Surprisingly, use of Rituximab alone as upfront therapy had poor hazard ratio in the cumulative group as well less aggressive PTLD subgroup comprising of early lesions and polymorphic PTLD.

Conclusions

Our experience with treatment and analysis of outcomes does challenge current role of Rituximab use in treatment of PTLD. Currently as we define role of immunotherapy in cancer treatment, the role of acute rejections and immunosuppressant in PTLD becomes more relevant as noticed in our study. This study was also able to find new prognostic factors and also verified other known prognostic factors.

PTLD: Survival and analysis of prognostic factors in a cohort of 138 patients from a single institution

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Background: The outcome and prognostic factors of post-transplant lymphoproliferative disorder (PTLD) varies in currently reported literature. We present one of the largest single institution retrospective analysis from University of Florida. Methods: Patient population was identified from EMR and charts were reviewed to collect data. Primary outcome was Overall survival (OS) and secondary outcome was identification of prognostic factors. Results: We identified 138 patients with PTLD from Sept 1994 to Feb 2016 (liver 34%, Kidney 23%, heart 21%, lungs 12%, kidney-pancreas 2% and BMT 6%). After survival analysis, 131 patients were further followed for secondary outcomes. 36% (n = 47) were less than 18 years of age, 60% (n = 83) were males. The median age of PTLD diagnosis was 44 years and the median duration from transplant to PTLD was 4.4 years. Pathology was early lesion 6% (n = 8), polymorphic 17% (n = 23), Monomorphic 71% (n = 93), Hodgkin/like 4.5% (n = 6). Extra-nodal site involvement was 61% (n = 80), most common being GI tract. Ann-Arbor stage distribution was stage I/II 50% (n = 65), stage III/IV 46% (n = 60). Initial treatment was immunosuppression (IS) reduction alone in 24% (n = 31), Rituximab (R) 24% (n = 31), chemotherapy (+/- R) 46% (n = 60). Most common chemo regimen was CHOP (+/-R) 27% (N = 36). After first line, 48% patients had complete remission (CR), 18% partial remission (PR) and 15% progressive disease (PD). Second line treatment was required in 33% (n = 44) and 10% (n = 13) patients required 3rdline treatment. Final analysis showed 61% (n = 80) achieved CR, 17% (n = 22) had PD, 56% (n = 74) patients were alive and 49% (n = 64) are alive without PTLD. Median OS was 14.99 years. Multivariate analysis identified transplant age, organ transplant recipients, PTLD diagnosis age, performance status, IPI score, graft rejection, history of malignancy and recipient EBV status as prognostic factors (p < .05). Conclusions: This study from a leading regional transplant center shows notable OS which is likely from improved immunosuppressive regimens, treatment modalities and large pediatric population. We identified various prognostic factors affecting survival and propose validation to generate prognostic score.

Association of allograft rejection with reduction of immunosuppression for post-transplant lymphoproliferative disorder: Analysis of a 20-year single-institutional experience

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Background: Post transplant lymphoproliferative disorder (PTLD) is a rare, but potentially fatal complication of transplantation and therapeutic immunosuppression (IS). The cornerstone of PTLD management is reduction of IS, which carries the risk of allograft rejection. Methods: Retrospective analysis of patients diagnosed with PTLD after solid organ (SOT) or allogeneic stem cell transplant (HSCT) at the University of Florida were identified through a review of individual EMR charts. This analysis focused on rates of allograft rejection and graft failure with RI. Results: Of 138 patients diagnosed with PTLD between 1994 and 2016, 15% (n = 20) experienced allograft rejection during PTLD treatment. The primary organ of transplant and rejection included liver (35%), lung (25%), heart (10%), HSCT (15%) and kidney (15%). Median age at PTLD diagnosis was 14.5 years (range 2-59), males (50%) and median time from transplant to PTLD diagnosis was 25 months (range 0-173). RI was a documented as a component of initial PTLD treatment in 19/20 (95%) patients, with 2/20 (10%) undergoing complete withdrawal of immunosuppression, 13/20 (65%) partial RI (withdraw of one or more drugs) and 3/20 (10%) dose reductions of their established IS regimen. One lung recipient (5%) was transitioned to an alternative agent, and one patient had no documented records of IS adjustment. Treatment for acute rejection included observation 2/20 (10%), pulse steroids 11/29 (55%) or IS increase 12/20 (60%). 7/20 (35%) received combination steroids and increased IS. Allograft failure developed in 5/20 (25%) (1 kidney, 1 lung, 1 heart, 1 liver, 1 BMT). Allograft failure was not shown to correlate with RPI score at diagnosis, organ transplanted, induction therapy at transplant or 3-year OS. Of note 5/5 (100%) of patients received Rituximab as part of initial treatment, versus 5/15 patients whose grafts survived. Conclusions: RI for PTLD is associated with moderate rates of response, however acute graft rejection is common and is associated with high rates of graft failure. PTLD may still have favorable outcomes when combining partial RI with chemotherapy and Rituximab.

The role of radiation therapy in pancreatic ductal adenocarcinoma in the neoadjuvant and adjuvant settings

Pancreatic adenocarcinoma (PCA) is associated with high rates of cancer-related morbidity and mortality. Yet despite modern treatment advances, the only curative therapy remains surgical resection. The adjuvant therapeutic standard of care for PCA in the United States includes both chemotherapy and chemoradiation; however, an optimal regimen has not been established. For patients with resectable and borderline resectable PCA, recent investigation has focused efforts on evaluating the feasibility and efficacy of neoadjuvant therapy. Neoadjuvant therapy allows for early initiation of systemic therapy and identification of patients who harbor micrometastatic disease, thus sparing patients the potential morbidities associated with unnecessary radiation or surgery. This article critically reviews the data supporting or refuting the role of radiation therapy in the neoadjuvant and adjuvant settings of PCA management, with a particular focus on determining which patients may be more likely to benefit from radiation therapy.

Indication of reactor ν(e) disappearance in the Double Chooz experiment

The Double Chooz experiment presents an indication of reactor electron antineutrino disappearance consistent with neutrino oscillations. An observed-to-predicted ratio of events of 0.944±0.016(stat)±0.040(syst) was obtained in 101 days of running at the Chooz nuclear power plant in France, with two 4.25 GW(th) reactors. The results were obtained from a single 10 m(3) fiducial volume detector located 1050 m from the two reactor cores. The reactor antineutrino flux prediction used the Bugey4 flux measurement after correction for differences in core composition. The deficit can be interpreted as an indication of a nonzero value of the still unmeasured neutrino mixing parameter sin(2)2θ(13). Analyzing both the rate of the prompt positrons and their energy spectrum, we find sin(2)2θ(13)=0.086±0.041(stat)±0.030(syst), or, at 90% C.L., 0.017<sin(2)2θ(13)<0.16.

Analysis of neutralizing antigenic sites on the surface of type A12 foot-and-mouth disease virus

A series of seven neutralizing monoclonal antibodies (nMAbs) directed against type A12 foot-and-mouth disease virus was used to generate neutralization-resistant variants. Both plaque reduction neutralization and microneutralization assays showed that the variants were no longer neutralized by the nMAbs used to generate them, although some of the variants still reacted with the nMAbs at high antibody concentrations. Results of cross-neutralization studies by both plaque reduction neutralization and microneutralization assays suggested the presence of at least one immunodominant antigenic site on the surface of type A12 foot-and-mouth disease virus, along with evidence of a second antigenic site on the viral surface. Two of the variants had reduced virulence in tissue culture as evidenced by their inability to inhibit cellular protein synthesis and a marked reduction in virus-induced cellular morphological alterations. Nucleotide sequencing of the variant genomes placed three epitopes of the major antigenic site on VP1 and the fourth epitope on VP3 and VP1. The one epitope of the minor site appears to reside only on VP1.

Competition for cellular receptor sites among selected aphthoviruses

The competition between different types of aphthoviruses (foot-and-mouth disease virus [FMDV]) for receptor site utilization was determined. The Southern African Territories (SAT) types of FMDV absorbed poorly to BHK-21 cells as measured by a radioactivity binding assay but grew to relatively high titers on these cells. On BK cells, however, all three SAT types bound well and competed with each other for receptor sites. In addition, unlabeled FMDV types A12 and O1B were able to completely inhibit the binding of 3H-uridine labeled SAT types. Unlabeled SAT, however, was only slightly able to inhibit the adsorption of labeled A12 and moderately inhibit the binding of labeled O1B. Saturation binding studies with homologous virus showed that BK cells contain at least 100-fold more receptor sites for types A12 and O1B than for the SAT types. Competitive binding analysis between type A12 FMDV and poliovirus and encephalomyocarditis virus revealed that these three viruses all used different receptor sites. Thus, different FMDV serotypes appear to utilize both common and unique receptor sites which are different from those of at least two other picornaviruses.