Inclusion Criteria:

- Patients older than 18 years

- Evidence of CUP based on histologic examination

- Negative search for the primary tumor site using recommended guidelines

- Disease classified as good prognosis according to the French classification criteria:
*performance status >2 and *normal serum LDH

- No prior chemotherapy

- No previous carcinoma, except basal-cell carcinoma of the skin

- Adequate renal function: measured or calculated creatinine clearance > 60 ml/min

- Absolute granulocyte count ≥ 1,500/mm3; platelets ≥ 100,000 mm3; bilirubin ≤ 1.5 fold
the upper normal value

- Signed informed consent

Exclusion Criteria:

- Patients infected by the Human Immunodeficiency Virus (HIV)

- CUP belonging to one of the following subgroups: 1) Axillary lymph node of an
adenocarcinoma in a woman; 2) Serous adenocarcinoma of the peritoneum in a woman; 3)
Undifferentiated carcinoma of the middle line in a young man; 4)Squamous-cell
carcinoma; 5) Neuroendocrine carcinoma; 6) Bone metastases with elevated serum
prostate specific antigen (PSA) in a man

- Patients who do not fit inclusion criteria.