AIM: It presents a clinical case of undifferentiated retroperitoneal liposarcoma with 5 years’ recurrence from the first operation for the rarity of the occurrence, the problems related to surgery and complementary therapeutic approach. MATERIAL OF STUDY: Male patient aged 73 was operated for removal of retroperitoneal mass with involvement of the right kidney at the Second University of Naples in the 2003. In accordance with the interdisciplinary board, complementary therapy is not indicated and follow-up program. The successive controls were negative until at least 2007. Reoperation for recurrence in 2008 for the presence of massive bone formation occupying a large part in the right half of the abdomen at the sub-hepatic level. In both cases histological examination showed undifferentiated liposarcoma. DISCUSSION: It is of unknown etiology and only 25% occurs in well-differentiated cells are also more than 100 histological subtypes, 85% are malignant. The most affected is the male sex and from the beginning looks like malignancy. The trend of growth in general is slow, and in most cases tends to recur over time. The role of chemotherapy and radiation therapy is controversial. CONCLUSIONS: The peculiarity of our case is higher than the average survival despite advanced age and presence of recurrence. This confirms the importance of surgical treatment, thus offering the patient a chance of better long-term survival.