Olatunji B. Alese

Contemporary Management of Borderline Resectable and Locally Advanced Unresectable Pancreatic Cancer

UNLABELLED Adenocarcinoma of the pancreas remains a highly lethal disease, with less than 5% survival at 5 years. Borderline resectable pancreatic cancer (BRPC) and locally advanced unresectable pancreatic cancer (LAPC) account for approximately 30% of newly diagnosed cases of PC. The objective of BRPC therapy is to downstage the tumor to allow resection; the objective of LAPC therapy is to control disease and improve survival. There is no consensus on the definitions of BRPC and LAPC, which leads to major limitations in designing clinical trials and evaluating their results. A multimodality approach is always needed to ensure proper utilization and timing of chemotherapy, radiation, and surgery in the management of this disease. Combination chemotherapy regimens (5-fluorouracil, leucovorin, irinotecan, oxaliplatin, and gemcitabine [FOLFIRINOX] and gemcitabine/nab-paclitaxel) have improved overall survival in metastatic disease. The role of combination chemotherapy regimens in BRPC and LAPC is an area of active investigation. There is no consensus on the dose, modality, and role of radiation therapy in the treatment of BRPC and LAPC. This article reviews the literature and highlights the areas of controversy regarding management of BRPC and LAPC. IMPLICATIONS FOR PRACTICE Pancreatic cancer is one of the worst cancers with regard to survival, even at early stages of the disease. This review evaluates all the evidence for the stages in which the cancer is not primarily resectable with surgery, known as borderline resectable or locally advanced unresectable. Recently, advancements in radiation techniques and use of better combination chemotherapies have improved survival and tolerance. There is no consensus on description of stages or treatment sequences (chemotherapy, chemoradiation, radiation), nor on the best chemotherapy regimen. The evidence behind the treatment paradigm for these stages of pancreatic cancer is summarized.

Aquaporins: Their role in gastrointestinal malignancies

Aquaporins (AQPs) are small (~30 kDa monomers) integral membrane water transport proteins that allow water to flow through cell membranes in reaction to osmotic gradients in cells. In mammals, the family of AQPs has thirteen (AQP0-12) unique members that mediate critical biological functions. Since AQPs can impact cell proliferation, migration and angiogenesis, their role in various human cancers is well established. Recently, AQPs have been explored as potential diagnostic and therapeutic targets in gastrointestinal (GI) cancers. GI cancers encompass multiple sites including the colon, esophagus, stomach and pancreas. Research in the last three decades has revealed biological aspects and signaling pathways critical for the development of GI cancers. Since the majority of these cancers are very aggressive and rapidly metastasizes, identifying effective targets is crucial for treatment. Preclinical studies have utilized inhibitors of specific AQPs and knock down of AQP expression using siRNA. Although several studies have explored the role of AQPs in colorectal, esophageal, gastric, hepatocellular and pancreatic cancers, there is no comprehensive review compiling the available information on GI cancers as has been published for other malignancies such as ovarian cancer. Due to the similarities and association of various sites of GI cancers, it is helpful to consider these results collectively in order to better understand the role of specific AQPs in critical GI cancers. This review summarizes the current knowledge of the role of AQPs in GI malignancies with particular focus on diagnosis and therapeutic applications.

Role of adiponectin in obesity related gastrointestinal carcinogenesis

Adiponectin is produced in the white adipose tissue and is known to have anti-metabolic and anti-inflammatory properties. Serum/plasma adiponectin levels depend on diet, physical activity, and inheritance. Epidemiologic observations suggest a potential link between obesity and gastrointestinal malignancies. Low levels of adiponectin, which are known to occur in obesity, may contribute to the high incidence of cancer in this population. This review discusses the biochemical and molecular evidence regarding the relationship between adiponectin and gastrointestinal carcinogenesis and provides several future perspectives on the role of adiponectin as a target for prevention and therapy.

Abstract CT116: BMS-986205, an optimized indoleamine 2,3-dioxygenase 1 (IDO1) inhibitor, is well tolerated with potent pharmacodynamic (PD) activity, alone and in combination with nivolumab (nivo) in advanced cancers in a phase 1/2a trial

Background: IDO1 is highly expressed in multiple cancers and may be an immunosuppressive mechanism for tumor escape via its production of metabolites that inhibit T-cell function. Nivo, a mAb that targets PD-1, causes IDO1 upregulation, supporting a rationale for combining it with an IDO1 inhibitor. Our preclinical program aimed to identify a best in class IDO1 inhibitor with favorable pharmacokinetic (PK) characteristics (Hunt J, et al. AACR 2017 [abst 6774]). Here we present BMS-986205, a selective IDO1 inhibitor validated in a novel phase 1/2a trial alone and in combination with nivo. Methods: During dose escalation, patients (pts) with advanced cancers were treated in escalating cohorts with BMS-986205 (25-200 mg as of Jan 5, 2017) orally once daily (QD) for 2 wk, followed by BMS-986205 + nivo 240 mg IV every 2 wk. Objectives included safety (primary), PK, and PD. Preclinical analyses included measurement of enzyme inhibition in HEK293 cells overexpressing human IDO1 or tryptophan 2,3-dioxygenase (TDO) and IFNγ-stimulated HeLa cells. Results: In support of clinical testing, BMS-986205 was evaluated preclinically. In vitro characteristics included potent inhibition of kynurenine (kyn) production in IDO1-HEK293 cells (IC50 = 1.1 nM) but not in TDO-HEK293 cells, sustained inhibition in IDO1 cell-based assays after washout, and single-digit nM potency in human tolerogenic MLR assays. Based on preclinical data, a 150 mg QD human dose was projected to maximally inhibit IDO1. In the ongoing clinical study, 42 pts have been treated. All treatment-related adverse events were grade 1/2 except three grade 3 toxicities (autoimmune hepatitis [dose limiting; BMS-986205 100 mg/nivo 240 mg], rash, and asymptomatic hypophosphatemia). Day 14 individual trough concentrations began exceeding the human whole blood IC50 starting with 25 mg QD, and the IC90 starting with 50 mg QD; all pts treated at 200 mg QD exceeded the IC90. Serum kyn was substantially reduced at all doses (> 45% mean reduction at each dose), with > 60% mean reduction at the 100 and 200 mg QD doses. Importantly, intratumoral kyn was reduced up to 90% in evaluable paired pre- and on-treatment samples. Conclusions: BMS-986205 is an optimized, once-daily, selective and potent oral IDO1 inhibitor at clinically relevant concentrations. It is well tolerated up to at least 200 mg in combination with nivo in this novel trial. Evidence of substantial serum kyn reduction was observed at doses as low as 25 mg QD; inhibition at 100 and 200 mg QD appears greater than that reported for other in-class compounds. In addition, we have presented the first evidence of intratumoral kyn reduction by an IDO1 inhibitor. These data suggest the potential of BMS-986205 as an IDO1 inhibitor with superior PD properties and support further evaluation in combination with nivo. Citation Format: Lillian L. Siu, Karen Gelmon, Quincy Chu, Russell Pachynski, Olatunji Alese, Paul Basciano, Justine Walker, Priyam Mitra, Li Zhu, Penny Phillips, John Hunt, Jayesh Desai. BMS-986205, an optimized indoleamine 2,3-dioxygenase 1 (IDO1) inhibitor, is well tolerated with potent pharmacodynamic (PD) activity, alone and in combination with nivolumab (nivo) in advanced cancers in a phase 1/2a trial [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr CT116. doi:10.1158/1538-7445.AM2017-CT116

Management patterns and predictors of mortality among US patients with cancer hospitalized for malignant bowel obstruction.

Malignant bowel obstruction affects an estimated 3% to 15% of patients with cancer, with a mean survival of <4 weeks reported in patients with inoperable malignant bowel obstruction. In the current study, the authors assessed predictors of survival and the influence of treatment modality in US patients with cancer who were hospitalized for malignant bowel obstruction.

Anaplastic lymphoma kinase (ALK) gene alteration in signet ring cell carcinoma of the gastrointestinal tract

Objectives: ALK-EML4 translocation is an established driver aberration in non-small cell lung cancer (NSCLC), with reported predilection for cases with signet ring histology. We assessed the presence of anaplastic lymphoma kinase (ALK) gene rearrangements in signet ring cancers arising in the stomach and colon. Methods: Histologically confirmed cases of signet ring adenocarcinoma of the stomach or the colon were identified. The presence of the classic ALK and EML4 fusion gene was initially determined by fluorescence in-situ hybridization (FISH) technique. Immunohistochemistry (IHC) was performed using two previously validated antibodies, ALK1 clone (1:100; DAKO) and 5A4 (Novocastra, Leica Biosystems) along with positive controls of ALK-translocated lung cancer. Results: We employed 42 cases of signet ring carcinoma diagnosed between 2001 and 2011; 25 gastric and 17 colon cancer. Median age 63.3 years; male/female 17/25; race, black 47.5%, white 47.5%, others, 5%; stage I, 21.4%; stage II, 31%; stage III, 26.2%; stage IV, 21.4%. One of 42 cases (2.3%) was positive for ALK translocation by FISH using the standard criteria of at least 15% positive cells for the break-apart signal (50–70 cells enumerated per case). Using a less restrictive cut-off of 10% positive cells, 7 cases (16%) were considered possibly positive. None of the ‘possibly positive’ cases was found to harbor ALK translocation by another molecular testing approach (IHC). IHC with two previously validated monoclonal antibodies showed 0 of 42 (0%) cases positive. Conclusions: ALK gene rearrangement is very rare in gastrointestinal cancers and enrichment strategy focusing on signet ring cell histology did not significantly improve the detection rate.

Rasburicase-induced methaemoglobinaemia and G6PD deficiency in an unusual suspect.

Screening patients at high risk of glucose-6-phosphate dehydrogenase (G6PD) deficiency (individuals of African and Mediterranean descent) is recommended prior to initiation of rasburicase. However, a high index of suspicion of G6PD deficiency is also crucial in a patient who develops methaemoglobinaemia or haemolytic anaemia following rasburicase therapy, irrespective of ethnic origin. We report a 56-year-old Hispanic male with mantle cell lymphoma with bulky lymphadenopathy who presented to the emergency department with dyspnoea and chest discomfort. Forty-eight hours prior to presentation, he had received chemotherapy with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone) with pegfilgrastim support and two 6 mg doses of intravenous rasburicase for the prevention of tumour lysis syndrome. Physical examination was unremarkable. Oxygen saturation (SpO2) was 85% on 100% oxygen via a non-rebreather mask at 10 l/min. Arterial blood gases showed a partial oxygen pressure (PaO2) of 216 mmHg. A full blood count showed haemoglobin concentration (Hb) 93 g/l and white blood cell count 77 9 9 10/l (0 8% lymphocytes). Serum creatinine was 73 37 lmol/l, uric acid 35 69 lmol/l and methaemoglobin 8 4%. Because of the presence of methaemoglobinaemia, intravenous methylene blue was administered. Eight hours later, the patient complained of diaphoresis and lightheadedness. SpO2 had dropped to 80% and Hb to 66 g/l. Total and direct bilirubin were 41 05 and 6 84 lmol/l respectively, haptoglobin was less than 10 mg/l and lactate dehydrogenase was elevated at 864 u/l (normal range 94–202), consistent with acute haemolytic anaemia. A peripheral blood film showed irregularly contracted cells and retraction of haemoglobin from the red cell membrane (left). Heinz bodies were demonstrated on supravital staining with new methylene blue (right). The patient was managed with supportive treatment and four units of packed red blood cells were transfused. By 24 h, methaemoglobin levels had dropped to zero. The suspicion of G6PD deficiency was confirmed by enzyme assay with an enzyme level of 1 5 u/g Hb (8 8–13 4). G6PD deficiency is associated with NADPH deficiency, and methylene blue is dependent on NADPH to reduce methaemoglobin to haemoglobin. This renders methylene blue ineffective in G6PD-deficient patients, and it may aggravate methaemoglobinaemia at high doses by oxidizing haemoglobin. Its use should be avoided.

Race-, Age-, and Gender-Based Characteristics and Toxicities of Targeted Therapies on Phase I Trials

Background: The impact of age-, gender-, and race-based differences on safety and efficacy in phase I clinical trials has not been well studied. Methods: We analyzed data from phase I clinical trials evaluating targeted biologic agents in patients with advanced solid malignancies. Race and gender distribution of enrolled patients was compared to the referral population demographics at the city, metro, and state levels. The association between age, gender, and race with type, frequency, and severity of treatment-emergent toxicities and clinical benefit was assessed using univariate and multivariable models. Results: Data from 117 eligible patients – Blacks/Caucasians/Others (27/85/5); male/female (66/51) – were obtained. Blacks were younger than Caucasian patients (median age of 56 vs. 62 years, p = 0.004). Nausea/vomiting was more frequent in female patients (43 vs. 24%, p = 0.03), while hematologic toxicity was more likely in Whites. While median time on treatment was comparable (113 vs. 91; p = 0.840), the median overall survival was significantly shorter for Blacks versus Caucasians (7.4 vs. 11.4 months; p = 0.0227). Black race (HR 2.11; 95% CI 1.24–3.60; p = 0.006) and older age (HR 1.03; 95% CI 1.00–1.06; p = 0.029) were associated with an increased risk of death. Conclusions: Age-, gender-, and race-based disparities were observed with specific toxicity and survival outcomes on phase I clinical trials of anticancer agents.

Phase 1b study of pasireotide, everolimus, and selective internal radioembolization therapy for unresectable neuroendocrine tumors with hepatic metastases: Pasireotide, Everolimus, and SIRT in NETs

Neuroendocrine tumors (NETs) metastasize to the liver. Everolimus and selective internal radioembolization (SIRT) are approved treatments. Pasireotide is a somatostatin analogue with an affinity for somatostatin receptors 1, 2, 3, and 5. Everolimus and pasireotide may potentiate SIRT radiosensitization and inhibit rebound angiogenesis. This study evaluated the safety of pasireotide, everolimus, and SIRT.

MicroRNAs as biomarkers and prospective therapeutic targets in colon and pancreatic cancers

Colon and pancreatic cancers have high mortality rates due to early metastasis prior to the onset of symptoms. Screening tests for colorectal cancer are invasive and expensive. No effective screening is available for pancreatic cancer. Identification of biomarkers for early detection in both of these cancers is being extensively researched. MicroRNAs (miRNA) are small non-coding molecule biomarkers that regulate cancers. Measurement of miRNAs in pancreatic fluid or blood could be a preferred non-invasive screening method. The regulation of colon and pancreatic cancers by miRNA is complex. miRNA play a central role in inflammation, invasiveness, and tumor progression in these two cancers, as well as regulation of the NF-κB pathway. miRNA’s evolving role in screening is also reviewed.