One study reported identification of a potential primary site in 14 of 22 patients.

Approximately 5% of patients present with no detectable primary site.

About two to four percent of all cancer patients have a cancer whose primary site is never identified.

About 2 to 4 percent of all cancer patients have a cancer whose primary site is never found.

That year, at the primary breeding site, only one adult male was found.

At the time of analysis, no patient had suffered from recurrence in primary site or neck area.

Small cell carcinomas (of any primary site) are usually positive.

Television has clearly superseded Congress as the primary site of political debate.

No primary site is found in 15 percent to 25 percent of such cases.

Surgical management of the more common primary sites is provided below.