A patient presents with a platelet count of 700 x 109/L with abnormalitites in size, shape and granularity of platelets. WBC count of 12 x 109 L, hemoglobin of 11g/d1 and the absence of the Philadelphia chromosome. The most likely diagnosis would be-
Polycythemia vera Essential thrombocythemia Chronic myeloid leukemia Leukemoid reaction