"We just don't know yet how much information in years to come we'll need to get from the primary tumor."

In some of these cases a primary tumor may appear later.

The most common primary tumors of the heart are benign.

Despite the use of techniques, in some cases the primary tumor remains unidentified.

This can sometimes lead to regression of the primary tumor.

These results have been confirmed in primary tumors and human models.

In many cases, the primary tumor is never found.

The most common primary tumor of the heart is the myxoma.

In many cases, it may be difficult to completely resect the primary tumor.

Most patients with an unidentified primary tumor have a cell type called adenocarcinoma.