There is no generally recommended treatment for all patients with CUPS. Whenever there is a likely primary origin, based on the opinion of the pathologist as well as the clinical , laboratory and imaging studies, the treatment will be given according to that probable diagnosis.
The prognosis for people with CUPS is highly variable because so many different tumors may be involved.

Standard Treatment  While no specific standard therapy is generally agreed upon for people with CUPS with no definable primary sources, these patients are sometimes treated with combination chemotherapy programs. If the disease appears to be localized , complete surgical removal or radical radiotherapy may occasionally result in a cure. But when the tumor has spread, investigational protocols might be considered.

Investigational 
• Combination chemotherapy (frequently including cisplatin).
• Hormonal therapy.
• New chemotherapeutic agents such as carboplatin alone or in combination with other drugs.