Exhibit 10.97

RITA MEDICAL SYSTEMS, INC.

2005 STOCK AND INCENTIVE PLAN

STOCK OPTION AGREEMENT

You
have been granted an option to purchase Common Stock of RITA Medical Systems, Inc. (the Company) as indicated on the Certificate of Stock Option Grant on the AST Stockplan website (the Certificate). Please
review the Certificate and this Stock Option Agreement before executing your grant at the AST Stockplan website at www.aststockplan.com.



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|Vesting/Exercise Schedule: |  | So long as your employment or consulting relationship with the Company continues, the Shares underlying this Option shall vest and become exercisable in accordance with the vesting schedule
indicated on the Certificate.                                                                                                                                                                                                                  
|                           | 
|Termination Period:        |  | Option may be exercised for three months after termination of employment or consulting relationship except as set out in Section 5 of the Stock Option Agreement (but in no event later
than the Expiration Date). Optionee is responsible for keeping track of these exercise periods following termination for any reason of his or her service relationship with the Company. The Company will not provide further notice of such
periods.

1. Grant of Option. The Company hereby grants you (Optionee), an
option (the Option) to purchase the total number of shares of Common Stock (the Shares) set forth in the Certificate, at the exercise price per Share set forth in the Certificate (the Exercise
Price) subject to the terms, definitions and provisions of the RITA Medical Systems, Inc. 2005 Stock and Incentive Plan (the Plan) adopted by the Company, which is incorporated in this Agreement by reference. Unless
otherwise defined in this Agreement, the terms used in this Agreement shall have the meanings defined in the Plan. This Stock Option Agreement shall be deemed executed by the Company and Optionee upon execution by such parties of the Certificate.

2. Designation of Option.This Option is intended to be an Incentive Stock Option as defined in Section 422 of the Code
only to the extent so designated in the Certificate, and to the extent it is not so designated or to the extent the Option does not qualify as an Incentive Stock Option under Applicable Law, it is intended to be and will be treated as a Nonstatutory
Stock Option.

Notwithstanding the above, if designated as an Incentive Stock Option, in the event that the Shares subject to this Option
(and all other Incentive Stock Options granted to Optionee by



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the Company or any Parent or Subsidiary, including under other plans of the Company) that first become exercisable in any
calendar year have an aggregate fair market value (determined for each Share as of the date of grant of the option covering such Share) in excess of $100,000, the Shares in excess of $100,000 shall be treated as subject to a Nonstatutory Stock
Option, in accordance with Section 5(c) of the Plan.

3. Exercise of Option. This Option shall be exercisable during its
term in accordance with the Vesting/Exercise Schedule set out in the Certificate and with the provisions of Section 10 of the Plan as follows:

(a) Right to Exercise.

(i) This Option may not be exercised for a fraction of a share.

(ii) In the event of Optionees death, disability or other termination of employment, the exercisability of the Option is governed by
Section 5 below, subject to the limitations contained in this Section 3.

(iii) In no event may this Option be exercised after
the Expiration Date of the Option as set forth in the Certificate.

(b) Method of Exercise.

(i) This Option shall be exercisable by delivering to the Company a Stock Option Cash Exercise Letter of Authorization which is a written notice of
exercise (in the form available from the AST Stockplan website) which shall state Optionees election to exercise the Option, the number of Shares in respect of which the Option is being exercised, and such other representations and agreements
as to the holders investment intent with respect to such Shares as may be required by the Company pursuant to the provisions of the Plan. The Cash Letter of Authorization shall be signed by Optionee and shall be delivered to the Company by
such means as are determined by the Administrator in its discretion to constitute adequate delivery. The Cash Letter of Authorization shall be accompanied by payment of the Exercise Price. This Option shall be deemed to be exercised upon receipt by
the Company of the Cash Letter of Authorization accompanied by the Exercise Price.

(ii) As a condition to the exercise of this Option and
as further set forth in Section 16 of the Plan, Optionee agrees to make adequate provision for federal, state or other tax withholding obligations, if any, which arise upon the vesting or exercise of the Option, or disposition of Shares,
whether by withholding, direct payment to the Company, or otherwise.

(iii) The Company is not obligated, and will have no liability for
failure, to issue or deliver any Shares upon exercise of the Option unless such issuance or delivery would comply with the Applicable Laws, with such compliance determined by the Company in consultation with its legal counsel. This Option may not be
exercised until such time as the Plan has been approved by the stockholders of the Company, or if the issuance of such Shares upon such exercise or the method of payment of consideration for such shares would constitute a violation of any applicable
federal or state securities or other law or regulation,



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including any rule under Part 221 of Title 12 of the Code of Federal Regulations as promulgated by the Federal
Reserve Board. As a condition to the exercise of this Option, the Company may require Optionee to make any representation and warranty to the Company as may be required by the Applicable Laws. Assuming such compliance, for income tax purposes the
Shares shall be considered transferred to Optionee on the date on which the Option is exercised with respect to such Shares.

4.
Method of Payment. Payment of the Exercise Price shall be by any of the following, or a combination of the following, at the election of Optionee:

(a) cash or check; or

(b) delivery of a properly executed exercise notice together with irrevocable
instructions to a broker approved by the Company to deliver promptly to the Company the amount of sale or loan proceeds required to pay the exercise price.

5. Termination of Relationship. Following the date of termination of Optionees Continuous Service Status for any reason (the Termination Date), Optionee may exercise the Option
only as set forth in the Certificate and this Section 5. To the extent that Optionee is not entitled to exercise this Option as of the Termination Date, or if Optionee does not exercise this Option within the Termination Period set forth in the
Certificate or the termination periods set forth below, the Option shall terminate in its entirety. In no event, may any Option be exercised after the Expiration Date of the Option as set forth in the Certificate.

(a) Termination.In the event of termination of Optionees Continuous Service Status other than as a result of Optionees
disability or death, Optionee may, to the extent Optionee was vested in the Shares at the date of such termination (the Termination Date), exercise this Option during the Termination Period set forth in the Certificate.

(b) Other Terminations.In connection with any termination other than a termination covered by Section 5(a), Optionee
may exercise the Option only as described below:

(i) Termination upon Disability of Optionee.In the event of termination of
Optionees Continuous Service Status as a result of Optionees disability, Optionee may, but only within six months from the Termination Date, exercise this Option to the extent Optionee was vested in the Shares as of such Termination
Date.

(ii) Death of Optionee. In the event of the death of Optionee (a) during the term of this Option and while an
Employee or Consultant of the Company and having been in Continuous Service Status since the date of grant of the Option, or (b) within thirty (30) days after Optionees Termination Date, the Option may be exercised at any time within
twelve months following the date of death by Optionees estate or by a person who acquired the right to exercise the Option by bequest or inheritance, but only to the extent the Shares are vested as of the Termination Date.

6. Non-Transferability of Option. Except as otherwise set forth in the Certificate, this Option may not be transferred in any manner
otherwise than by will or by the laws of descent



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or distribution and may be exercised during the lifetime of Optionee only by him or her. The terms of this Option shall
be binding upon the executors, administrators, heirs, successors and assigns of Optionee.

7. Tax Consequences. Although
Optionee is being provided in the Plan prospectus a description of certain tax consequences of transactions related to the Option, Optionee remains responsible for all such tax consequences and the Company shall not be deemed to provide any
individual tax advice with respect thereto. Optionee should obtain advice from an appropriate independent professional adviser with respect to, and under the laws of Optionees state and country of residence and/or citizenship, the taxation
implications of the grant, exercise, assignment, release, cancellation or any other disposal of this Option and on any subsequent sale or disposition of the Shares.

8. Effect of Agreement. Optionee acknowledges receipt of a copy of the Plan and Plan prospectus and represents that he or she is familiar with the terms and provisions thereof (and has had an opportunity
to consult counsel regarding the Option terms), and hereby accepts this Option and agrees to be bound by its contractual terms as set forth herein and in the Plan. Optionee hereby agrees to accept as binding, conclusive and final all decisions and
interpretations of the Administrator regarding any questions relating to this Option. In the event of a conflict between the terms and provisions of the Plan and the terms and provisions of the Certificate and this Agreement, the Plan terms and
provisions shall prevail. This Option, including the Plan, constitutes the entire agreement between Optionee and the Company on the subject matter hereof and supersedes all proposals, written or oral, and all other communications between the parties
relating to such subject matter.

By your electronic signature and the electronic signature of the Company, you and the Company agree that
this Option is granted under and governed by the terms and conditions of the RITA Medical Systems, Inc. 2005 Stock and Incentive Plan which is attached and made a part of this document.

In addition, you agree and acknowledge that your rights to any Shares underlying the Option will be earned only as you provide services to the Company
over time, that the grant of the Option is not as consideration for services you rendered to the Company prior to your Vesting Commencement Date, and that nothing in the Certificate or the attached documents confers upon you any right to continue
your employment or consulting relationship with the Company for any period of time, nor does it interfere in any way with your right or the Companys right to terminate that relationship at any time, for any reason, with or without cause.

RITA Medical Systems, Inc.



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