Rejoicing after a stellar debut at the bourses, Thyrocare Technologies ended the day with 38.7 percent gains over its issue price of Rs 446 per share. The stock ended at Rs 618.80 per share, hitting intraday high of Rs 665 and an intraday low of Rs 605.80 on the NSE. The diagnostics company debuted at Rs 665 per share on the NSE, 49 percent premium to its issue price at Rs 446. However, the stock fell around 7 percent from its opening price. Market capitalisation of the new kid in the block stands at Rs 3,320.65 crore as of May 9.