Splenic marginal zone lymphoma (SMZL) is an indolent non-Hodgkin lymphoma but about 10-15% of patients may undergo transformation to an aggressive lymphoma, commonly diffuse large B-cell lymphoma (DLBCL). Although SMZL genomic profile has been largely investigated, the genetic mechanisms leading to this transformation are still unknown. To characterize the genomic landscape of transformed SMZL in order to establish the underlying mechanisms associated with transformation and the potential clonal evolution during this event. Methods: Methods:

INTRODUCTION:Retroperitoneal liposarcomas are unusual tumors. Their biological and clinical features different from other retroperitoneal sarcomas.AIM:To analyze our series of retroperitoneal liposarcomas.PATIENTS AND METHODS:Retrospective study of 10 patients with retroperitoneal liposarcoma diagnosed in the last 16 years at our institution. Symptoms, diagnosis, treatment and prognosis were analyzed.RESULTS:Radical resection was done in all cases. Postoperative mortality was 10%. Complementary treatment was considered in each patient. Recurrent disease occurred in 8 patients (14 recurrences), during follow up. In 42% of them recurrences were resected. Actuarial 5-year survival rate was 44%.CONCLUSION:Poor prognosis of retroperitoneal liposarcoma is due to its high recurrence rate.

We present a case of a large primary leiomyosarcoma of gallbladder in a 77 years old patient, and completely excised by surgery.

A polypoid tumor located in the renal pelvis with both epithelial and sarcomatous elements is described. The epithelial component was histologically benign and resembled urothelium. The sarcomatous component showed undifferentiated cells and rhabdomyoblastic elements. The term mesonephric adenosarcoma is proposed to describe this biphasic tumor. Although this tumor might be histogenetically related to Wilms' tumor, it is morphologically distinct, and might behave more aggressively.