Image source: Getty Images.

Genomic Health (NASDAQ:GHDX) is scheduled to report second-quarter earnings after the bell on Tuesday. Here are three things to pay attention to as the company updates investors on its progress.

1. Tests delivered

In the long term, growth in the number of tests delivered, rather than revenue growth, is a better measure of Genomic Health's future. Getting doctors into a routine of doing the tests, even if Genomic Health isn't being reimbursed for the tests, will help sales in future quarters as Genomic Health works to secure reimbursement for its newer tests.

Additional data showing the predictability of Genomic Health's invasive breast cancer test helped boost the number of invasive breast cancer tests delivered in the U.S. by 11% year over year in the first quarter. Look for invasive breast cancer test growth in Europe with a new access program in France and updated treatment guidelines in Germany.

Genomic Health also needs its newer tests -- DCIS breast cancer test for earlier-stage patients and prostate cancer test, which grew volume by 33% and 18% year over year, respectively, in the first quarter -- to continue their stellar launches.

2. Prostate cancer test reimbursement

While test volume is important in the long term to move toward profitability in the short term, Genomic Health needs to execute on reimbursement for its prostate cancer test. Medicare began covering the test in October, but only about half of the eligible Medicare revenue was recorded in the first quarter.

Genomic Health is working on collecting the necessary data for Medicare billing to increase the conversion rate. Repeat business, which was up 33% in the first quarter compared to the fourth quarter of 2015, should help with that endeavor as doctors' offices begin to understand what's required to gain reimbursement.

3. Liquid biopsy launch

In mid-June, Genomic Health announced the launch of its Oncotype SEQ Liquid Select, a non-invasive liquid biopsy tests. The test uses sequencing of tumor DNA that's circulating in the blood to determine mutations in 17 different genes that make a tumor sensitive or resistant to drugs, helping doctors to pick the best treatment.

The test can be used on solid tumors, including lung, breast, colon, melanoma, ovarian, and gastrointestinal stromal tumors, but Genomic Health plans to initially focus on doctors treating lung cancer patients because it's harder to get samples directly from lung tumors, making the blood-based test a welcome alternative.

With only two weeks of the launch in the second quarter, the Liquid Select test isn't likely to affect revenue much, but the company now has an additional month of selling the test, allowing management to give a qualitative assessment of the launch. Investors may also get more information about other liquid biopsy tests Genomic Health has planed.

One of those was announced last month when Genomic Health signed a deal with Epic Sciences to offer Epic's liquid biopsy test that measures AR-V7 in prostate cancer patients. The test will launch in the U.S. in early 2017. It'll be interesting to hear whether management plans to do more licensing deals or if this was a one-off deal with most of the new liquid biopsy tests coming through internal development.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.