This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Misc. (W.B.C), Subject name: Pathology
A patient presents with a platelet count of 700x109/L with abnormalities in size, shape and granularity of platelets. WBC count of 12x109 L, hemoglobin of 11g/dl and the absence of the Philadelphia chromosome. The most likely diagnosis would be- 
Select and explain. 
A. Polycythemia vera, B. Essential thrombocythemia, C. Chronic myeloid leukemia, D. Leukemoid reaction
B: Essential thrombocythemia
Answer: B: Essential thrombocythemia 
Explanation: Ans. (b) Essential thrombocythemia(Ref: Robbins 9th/pg 619-620; 8th/pg 629-630)In the given scenario, a patient presents with thrombocytosis with abnormalities in size, shape and granularity of platelets, with normal WBC count & hemoglobin and the absence of the Philadelphia chromosome. The most likely diagnosis in this case would be Essential Thrombocythemia