Utilizing Sysmex RET He to Evaluate Anemia in Cancer Patients

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1 Utilizing Sysmex RET He to Evaluate Anemia in Cancer Patients Ellinor I. Peerschke, Ph.D., F.A.H.A. Vice Chair, Laboratory Medicine Chief, Hematology & Coagulation Laboratory Services Memorial Sloan Kettering Cancer Center New York, New York Anemia is a major cause of morbidity in cancer patients, often associated with poor physical performance Typical Scenario: 72 yo woman with history of colon cancer, currently no evidence of disease, returns for annual outpatient monitoring visit and complains of fatigue Automated CBC with diff is ordered and performed in the outpatient setting Hgb is 9.6g/dl, down from 12.0g/dl last year Physician notes: Anemia may explain fatigue Will check iron studies May benefit from iron supplementation 1

2 What happens next? Regional Lab Workflow Blood is drawn before patient meets with provider CBC with differential and routine chemistry testing is performed on site Chemistry analysis is performed on plasma Additional testing is sent to Central Laboratory May require an additional tube of blood May require different sample type (serum) Delay in testing Iron studies and ferritin are a frequent ADD ON Performed on serum Patient Blood sample is sent to Main Campus for analysis Result of Iron Studies Serum iron: 32 mcg/dl ( mcg/dl) LOW UIBC: 384mcg/dL ( mcg/dl) HIGH IBC: Total 416mcg/dL ( mcg/dl) Transferrin Saturation 8% LOW Ferritin 13 ng/ml ( ng/ml) LOW Interpretation Anemia is due to iron deficiency Patient is notified of results by telephone next day with recommendation for iron supplementation and follow up What could be done at the point of care to facilitate patient management? Can RET He be useful? 2

3 Presentation Overview What is RET He? How can Ret He aid in the evaluation of anemia? What are the performance characteristics of RET He in cancer patients at MSKCC? What is the potential impact of RET He on anemia evaluation at MSKCC? What is RET He? RET He reports the Hgb content of Reticulocytes RET He is a component of automated Reticulocyte Analysis on Sysmex XE and XN analyzers RET He is equivalent to CHr on Siemens Advia What information does RET He add to CBC and RBC indices? RET He provides an indirect measure of iron available for RBC production during the past 2 4 days A low RET He, is an indicator of Functional Iron Deficiency 3

4 How could this patient have benefitted from RET He analysis? Patient s RET He: 28 pg Reference Range: pg MSK cut off to rule out iron deficient hematopoiesis: 32 pg Impact: Suspect iron deficiency Order appropriate work up before patient leaves facility How is RET He/CHr Used Clinically? To identify iron deficiency in Infants/children Patients with Chronic Kidney Disease/Renal Dialysis Established parameter of NKF guidelines for assessing initial iron status of patients with chronic kidney disease on hemodialysis Patients receiving erythropoietin therapy Accelerated RBC production may exceed functional iron availability in the bone marrow Presurgical Anemia Management Pregnancy Adult Blood Donors Response to iron therapy Iron Deficiency in Pregnancy Ervasti et al., Eur J Haematology, 2007 Diagnosis of iron deficiency complicated by Expanding plasma volume (hemodilution) Accelerated erythropoiesis Advia CHr <31.9 pg Sensitivity 80.7% Specificity 71.3% 4

5 Iron Deficiency in Patients on Chronic Renal Dialysis Brugnara et al., Clin Lab Haematol, 2006 Serum markers of iron deficiency are unreliable Inflammation Uremia RET He <27.2 pg Sensitivity 93.3% Specificity 83.2% AUC: Anemia in Elderly Patients Karlsson T., Anemia, 2011 Sweden Diagnosis of iron deficiency CHr <30.5 pg Sensitivity 93% Specificity 69% Joosten E, et al., Europ J Int Med, 2013 Belgium Diagnosis of iron deficiency RET He <26 pg Sensitivity 85% Specificity 69% Anemia in Cancer Patients Complex etiology Chronic disease/inflammation Chemotherapy Bone marrow failure Bleeding Nutritional deficiencies Iron deficiency Conventional markers such as serum iron, transferrin saturation and ferritin are disturbed during an acute phase response and in the presence of severe diseases Interpretation of results is challenging 5

6 Establishing the cause of anemia in cancer patients impacts treatment Oncology practice guidelines Investigate cause of anemia if Hgb < 11g/dl Hgb falls by >2 g/dl (Steinmetz HT, Therap Adv in Hematol 2012) Treatments RBC transfusion Use of erythropoiesis stimulating agents Oral or IV iron Investigation of Anemia in Cancer Patients Distinguishing iron deficient erythropoiesis from erythropoietin dependent erythropoiesis can be challenging in cancer patients Biochemical markers of iron status Ferritin, serum iron, transferrin saturation Ferritin increases in chronic disease Transferrin decreases in chronic disease Serum iron may be normal in chronic disease Hepcidin regulates iron availability for erythropoiesis and is upregulated during inflammation 6

7 Ferritin may be a tumor marker Ferritin overexpression has been observed in Hepatocellular carcinoma Hodgkin s lymphoma Breast cancer Pancreatic cancer Elevated ferritin levels are associated with more progressive disease and shorter survival Decreases in ferritin levels during chemotherapy are associated with response to therapy Hematologic Markers, MCV and MCH, are challenged to provide adequate information regarding iron deficient hematopoiesis Insufficient sensitivity Affected by RBC life span days In contrast, RET He Provides a snapshot of iron available for erythropoiesis during the last 2 4 days RET He correlates with Bone Marrow Iron Stores Mast et al., Blood 2002 Bone marrow iron assessed on aspirate using Prussian Blue CHr <28 pg Sensitivity 74% Specificity 73% Superior to ferritin, transferrin saturation, and MCV 7

8 MSKCC Study Goal Evaluate the ability RET He to rule out iron deficient erythropoiesis in an unselected cancer patient population at MSKCC solid tumors hematologic malignancies undergoing diverse chemotherapy and/or radiation treatment regimens Focus Patients being evaluated for functional or absolute iron deficiency using serum markers This study was performed in collaboration with Peter Maslak, M.D. Melissa Pessin, M.D., Ph.D. Nenita Francisco MT (ASCP) Supported by Sysmex America, Inc. Study Sample Selection EDTA anticoagulated, waste peripheral blood Simultaneously submitted serum samples for iron studies Collection period: 5/25/ /7/2012 8

9 Study Design Samples were analyzed on Sysmex XE2100 for RET He within 6 hours of blood collection Results were correlated with Hgb Serum iron Transferrin saturation Ferritin Study approved by MSKCC IRB Study Definition of Iron Deficiency Biochemical Diagnosis Based on National Kidney Foundation Guidelines Serum iron (<40 mcg/dl) Serum transferrin saturation (<20%) Serum ferritin level (<100 ng/ml) Study Limitations Retrospective study Anemia diagnosis was inferred from biochemical iron studies and medical record review Selection bias patients tested for iron deficiency Difficulty defining true iron deficiency Absence of definitive tests or markers bone marrow iron soluble transferrin receptor Predominant patient population with anemia of chronic disease 9

10 Patient Characteristics: (n=209 ) MALE FEMALE Number Age, years Mean* (p=0.006) Median Age (years) Age Range (years) Pediatric Cases (<18 years) Anemia Hgb: <11 g/dl Anemia Hgb: < 12g/dl N=4 (ages: 1.5, 3, 16,16 years) N=4 (ages: 11, 15, 17, 17, years) N=43 (37.7%) N=50 (52.6%) N=62 (54.3%) Hematologic Findings Gender Hgb (g/dl) (<11 g/dl) MCV (fl) (<80fl) Serum Iron (mcg/dl) (<40 mcg/dl) Transferrin Saturation (%) (<20%) Ferritin (ng/ml) (<100 ng/ml) Male Female * p=0.013 RET He Values in Study Population Normal reference range: pg RET He: Male: Mean: 33.2 pg SD:4.3 Median: 34.2 Female: Mean 33.1 pg SD: 4.5 Median: 33.5 P=

11 Significant RET He Correlations P value Hgb (g/dl) MCV (fl) Serum Iron (mcg/dl) Transferrin Saturation (%) Ferritin (ng/ml) Determining the RET He threshold for identifying iron deficiency pg Sensitivity, Specificity Sensitivity Specificity RET He (pg) A wide variation in thresholds are quoted in the literature, depending on study population: pg Condition Iron Deficiency: Transferrin Saturation <20% and Serum Fe < 40 mcg/dl, & ferritin <100 ng/ml RET He Performance RET He Sensitivity Specificity Negative Predictive Value (%) Positive Predictive Value (%) < < < < < Comparison with Hgb (<12g/dl males, <11 g/dl females) & MCV (<80fl)

12 RET He Performance RET He Diagnostic Performance Cancer Patients with Anemia (Hgb < 11g/dl) & Iron Deficiency defined by NKD Guidelines n=23 <28 pg Iron Deficiency n = 11 <31 pg Iron Deficiency n = 19 <32 pg Iron Deficiency n = 20 FN: n=12 FN: n=4 FN: n=3 Evaluation of False Negative Cases at a RET He cut off of 32 pg False Negative Cases (n=3) Mild Anemia with Normal MCV None of the patients would have been considered iron deficient, using in house reference ranges for serum iron biomarkers In house reference ranges are more stringent than CKD recommendations» Serum iron: <34 mcg/dl vs 40 mcg/dl» Ferritin: < 22 ng/dl male vs 100 ng/dl < 6 ng/dl female Based on in house reference ranges for iron studies, RET He results for these patients are more correctly categorized as True Negative 12

13 Utilization of RET He to evaluate patients receiving iron supplementation Patient Receiving Iron Supplements n=15 Patients Deemed Iron Sufficient n=13 Patients with Ongoing Iron Deficiency n=2 >28 n=13 >31 n=12 >32 n=10 <28 n=1 < 31 n=2 <32 n=2 Misclassifications: n=0 n=1 n=3 n=1 Misclassifications: n=0 n=0 A lower RET He cut off may be indicated for determining response to iron therapy RET He of < 32 pg can rule out Iron Deficiency in patients with decreased RBC Production Absolute Reticulocyte Count < 20 X 10 9 /L (N=19) TP N=4 FP N=4 TN N=11 FN N=0 Sensitivity: 100% Specificity: 73.3% Negative Predictive Value: 100% Positive Predictive Value: 50% Iron deficiency: serum iron < 40 mcg/ml, transferring saturation < 20% What is the impact of RET He on assessing patients with anemia? Anemia N=93 RET He < 32 pg N=43 Rapid rule out of iron deficient hematopoiesis in 54% of cases 13

14 RET He can rapidly rule out iron deficient erythropoiesis Patient Screening using n=209 80% of patients with suspicion for iron deficiency (iron studies ordered) rule out for iron deficient erythropoiesis <32 pg and Hgb <11 g/dl n=43 BENEFITS of RET He: Reduction in unnecessary testing Decreased blood draws from patients Conclusion RET He is useful to rapidly evaluate anemia in cancer patients RET He is useful as a screen for iron deficiency/iron deficient erythropoiesis RET He is useful for interpreting the work up of anemia in cancer patients Appropriate RET He cut offs must be established/verified by each laboratory 14