The company said testing services revenues more than doubled during the quarter as its AlloSure kidney transplant diagnostic continued to penetrate the market.
MDx revenues increased 3 percent to $158.0 million, but excluding non-recurring royalty revenue in the prior-year period, MDx revenues increased 10 percent.
The company said its molecular collection systems products saw the highest revenue growth during the quarter as product revenues rose 6 percent overall.
Myriad CEO Mark Capone said earnings during the quarter exceeded expectations based on strong volume growth from hereditary cancer and new products.
Total revenues were down due to lower assay revenues, which shrank 11 percent from a year ago. Sample-to-answer molecular product revenues grew 15 percent.
The firm beat Wall Street analyst estimates for revenues and earnings per share in the third quarter.
Test volume for the firm's Cologuard colorectal cancer screening test rose 49 percent year over year during the quarter.
The firm beat analysts' revenue expectations for the quarter while its net loss was in line with predictions.
The company missed analysts' consensus estimate for revenues but beat Wall Street expectations on the bottom line.
The firm said genomic testing volume rose 23 percent year over year, and raised its revenue guidance for full-year 2018.