RITA Medical Systems, Inc. Announces USPTO Confirms Key Claims In Patent No. 5,683,384

FREMONT, Calif., Feb. 27 /PRNewswire-FirstCall/ -- RITA Medical Systems, Inc. , a publicly-traded medical device company focused solely on cancer therapies, today announced that the United States Patent and Trademark Office (USPTO) has confirmed key patent claims as amended in the U.S. Patent No. 5,683,384 relating to ablation with radiofrequency (RF) and microwave technology. The '384 patent was issued on November 4, 1997 and is the sole property of RITA Medical Systems, Inc.

The Company noted that during reexamination proceedings at the USPTO, key patent claims in the '384 Patent were amended to recite RF and microwave technology. In an Office communication, the Patent Office stated that the prior art of record in the reexamination of the '384 Patent did not anticipate or make obvious the amended claims of the '384 Patent.

Darrin Uecker, Chief Technology Officer of RITA Medical commented, "We are pleased that the patent office reached a positive conclusion regarding key claims in the '384 patent. We believe the inclusion of the use of microwave as well as radiofrequency energy to perform ablations broadens RITA's intellectual property portfolio and is an important component of ensuring RITA's continuing dominant position in innovative ablation technologies."

About RITA Medical Systems, Inc.

RITA Medical Systems develops, manufactures and markets innovative products for cancer patients including radiofrequency ablation (RFA) systems for treating cancerous tumors as well as percutaneous vascular and spinal access systems. The Company's oncology product lines include implantable ports, some of which feature its proprietary Vortex(R) technology; tunneled central venous catheters; and safety infusion sets and peripherally inserted central catheters used primarily in cancer treatment protocols. The product line also includes the HABIB 4X resection device which coagulates a "surgical resection plane" and is designed to facilitate a fast dissection in order to minimize blood loss and blood transfusion during surgery. The proprietary RITA RFA system uses radiofrequency energy to heat tissue to a high enough temperature to ablate it or cause cell death. In March 2000, RITA became the first RFA Company to receive specific FDA clearance for unresectable liver lesions in addition to its previous general FDA clearance for the ablation of soft tissue. In October 2002, RITA again became the first company to receive specific FDA clearance, this time for the palliation of pain associated with metastatic lesions involving bone. The RITA Medical Systems website is at www.ritamedical.com.

The statements in this news release related to the Company's intellectual property portfolio, the Company's competitive position in innovative ablation technologies, and the Company's ability to develop, acquire or license new products and services, are forward-looking statements involving risks and uncertainties that could cause actual results to differ materially from those in such forward-looking statements. Such risks and uncertainties include but are not limited to: the Company's ability to protect its intellectual property rights; potential infringement of the intellectual property rights of others; the Company's historical and future operating results and profitability; market acceptance of any new products or services of the Company; competitive pressures; the development of alternative therapies; physician training efforts; and general economic and political conditions. Information regarding these risks and other risks and uncertainties is included in the Company's filings with the Securities and Exchange Commission.

CONTACT: investors, Doug Sherk, dsherk@evcgroup.com, or JenniferBeugelmans, both of EVC Group, +1-415-896-6820, for RITA Medical Systems,Inc.; or Stephen Pedroff, VP Marketing Communications of RITA MedicalSystems, Inc., +1-510-771-0400, or spedroff@ritamed.com; or media, SteveDiMattia of EVC Group, +1-646-277-8706, or sdimattia@evcgroup.com, for RITAMedical Systems, Inc.

Web site: http://www.ritamedical.com/