Primary signet ring cell carcinoma of the colon and rectum.

Colorectal primary signet ring cell carcinoma (SRCC) is a rare entity accounting for nearly 1% of all colorectal carcinomas. It is an independent prognostic factor associated with less favorable outcome. This aggressiveness is mainly due to the intrinsic biology of these tumors.

Complete histologic response to chemotherapy in a patient with a mediastinal yolk sac tumor: a case report.

Background: Malignant mediastinal germ cell tumors are a rare disease and represent only 1% to 4% of all mediastinal tumors. Gonadal germ cell tumors are generally the most common type and constitute 90% of germ cell tumors. The mediastinum is the second most frequently affected area ahead of other extragonadal areas, which include the retroperitoneum, the sacrococcygeal area, and the central nervous system.

Primary lymphoma of the prostate treated with rituximab-based chemotherapy: a case report and review of the literature.

Introduction: Primary lymphoma of the prostate is very rare. In this paper we present a case of early stage non-Hodgkin lymphoma of the prostate managed with six cycles of rituximab-based chemotherapy, and review the related literature.

Case Presentation: An 84-year-old man was admitted to our hospital having signs and symptoms suggestive of prostatic disease for 3 years.