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                                                                   Exhibit 10.31

                          REGISTRATION RIGHTS AGREEMENT

      This Registration Rights Agreement (this "Agreement") is made as of June
24, 2002 by and among Endocare, Inc., a Delaware corporation (the "Company"),
and Cryomedical Sciences, Inc. (the "the Seller") .

      WHEREAS, The Company and Cryomedical Sciences, Inc., a Delaware
corporation are parties to an Asset Purchase Agreement dated May 28, 2002 (the
"Purchase Agreement");

      WHEREAS, the Seller is subject to the terms of a Lock-Up Agreement of even
date herewith with the Company (the "Lock-Up Agreement"); and

      WHEREAS, In order to induce the parties to the Purchase Agreement to
consummate the transactions contemplated thereby, the Seller and the Company
hereby agree that this Agreement, among other things, shall govern the rights of
the Seller to cause the Company to register shares of Common Stock of the
Company issuable to the Seller.

      NOW, THEREFORE, in consideration of the mutual promises, representations,
warranties, covenants and conditions set forth in this Agreement and the
Purchase Agreement, the parties hereto agree as follows:

      1. REGISTRATION RIGHTS. The Company covenants and agrees as follows:

            1.1 DEFINITIONS. For purposes of this Section 1:

                  (a) The term "Act" means the Securities Act of 1933, as
amended.

                  (b) The term "Form S-3" means such form under the Act as in
effect on the date hereof or any registration form under the Act subsequently
adopted by the SEC which permits inclusion or incorporation of substantial
information by reference to other documents filed by the Company with the SEC.

                  (c) The term "Holder" means any person owning or having the
right to acquire Registrable Securities or any assignee thereof in accordance
with Section 1.7 hereof.

                  (d) The term "1934 Act" shall mean the Securities Exchange Act
of 1934, as amended.

                  (e) The term "register," "registered," and "registration"
refer to a registration effected by preparing and filing a registration
statement or similar document in compliance with the Act, and the declaration or
ordering of effectiveness of such registration statement or document.

                  (f) The term "Registrable Securities" means (i) the Common
Stock of the Company issued to the Seller as a result of the consummation of the
transactions contemplated by the Purchase Agreement and (ii) any Common Stock of
the Company issued as (or issuable upon the conversion or exercise of any
warrant, right or other security which is


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issued as) a dividend or other distribution with respect to, or in exchange for
or in replacement of the shares referenced in (i) above, excluding in all cases,
however, any Registrable Securities sold by a person in a transaction in which
his rights under this Section 1 are not assigned pursuant to the terms of this
Agreement.

                  (g) The number of shares of "Registrable Securities then
outstanding" shall be the sum of the number of shares of Registrable Securities
which are (i) then outstanding Common Stock and (ii) Common Stock issuable
pursuant to then outstanding securities that are convertible or exercisable into
Common Stock that were issued as a dividend or other distribution with respect
to the Registrable Securities.

                  (h) The term "SEC" shall mean the Securities and Exchange
Commission.

            1.2 FORM S-3 REGISTRATION. Subject to compliance with the terms of
the Lock-Up Agreement, the Company will:

                  (a) as soon as reasonably practicable after the Closing Date
(as defined in the Purchase Agreement), but in no event more than 90 days
thereafter, file one registration statement on Form S-3, and, as soon as
reasonably practicable thereafter, effect all such qualifications and
compliances as may be reasonably necessary and as would permit or facilitate the
sale and distribution of all or such portion of such Holder's or Holders'
Registrable Securities; provided, however, that the Company shall not be
obligated to file such registration statement, or effect any such qualification
or compliance, pursuant to this Section 1.2: (i) if Form S-3 is not available
for such offering by the Holders; (ii) unless and until the Company has received
the consents and the financial statements and other financial information
required by the Act and the SEC to be included in such registration statement
from the independent certified public accountants of both the Company and the
Seller; (iii) if the Company shall furnish to the Holders a certificate signed
by the Company's Chief Executive Officer stating that in the good faith judgment
of the Board, it would be seriously detrimental to the Company and its
stockholders for such Form S-3 Registration to be effected at such time, in
which event the Company shall have the right to defer the filing of the Form S-3
registration statement for a period of not more than 90 days after receipt of
the request of the Holder or Holders under this Section 1.2; provided, however,
that the Company shall not utilize this right more than twice in any 12 month
period; or (iv) in any particular jurisdiction in which the Company would be
required to qualify to do business or to execute a general consent to service of
process in effecting such registration, qualification or compliance. The Company
represents and warrants that, as of the date of this Agreement (i) Form S-3 is
available for the offering, and (ii) it is not aware of any fact which would
make it seriously detrimental to the Company to file the Form S-3 registration
contemplated by this Agreement. The Company covenants and agrees: (i) the sale
by Seller of Registrable Securities is not a fact that would make it seriously
detrimental to the Company to file the Form S-3 registration contemplated by
this Agreement, and (ii) to use its reasonable commercial efforts to obtain
necessary consents, financial statements and other financial information from
the independent certified public accountants of the Company.

                  (b) All expenses incurred in connection with a registration
effected pursuant to this Section 1.2, including (without limitation) all
registration, filing, qualification,


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printer's and accounting fees (including the reasonable fees and disbursements
of one counsel for the Holders not to exceed $5,000) shall be borne by the
Company. Notwithstanding the foregoing, the fees and expenses of any persons
(other than the fees and expenses of counsel for the Holders as provided for
above) retained by a Holder, the fees and expenses customarily reimbursed or
paid by issuers or selling security holders on behalf of underwriters in
underwritten offerings (in the case of an underwritten offering), and any
discounts, commissions or broker's fees or fees of similar securities industry
professionals and any transfer taxes relating to the distribution of the
Registrable Securities by a Holder, will be payable by such Holder, and the
Company will have no obligations to pay such amounts.

            1.3 OBLIGATIONS OF THE COMPANY. Whenever required under this Section
1 to effect the registration of any Registrable Securities, the Company shall,
as expeditiously as reasonably possible:

                  (a) Prepare and file with the SEC a registration statement
with respect to such Registrable Securities and use reasonable efforts to cause
such registration statement to become effective, and, keep such registration
statement effective for a period of one year or until such earlier date as all
Registrable Securities have been sold; provided, however, that (i) such one year
period shall be extended for a period of time equal to the period the Holder
refrains from selling any securities included in such registration at the
request of an underwriter of Common Stock (or other securities) of the Company
or the Company; and (ii) in the case of any registration of Registrable
Securities on Form S-3 which are intended to be offered on a continuous or
delayed basis, such one year period shall be extended, if necessary, to keep the
registration statement effective until all such Registrable Securities are sold,
provided that Rule 415, or any successor rule under the Act, permits an offering
on a continuous or delayed basis, and provided further that applicable rules
under the Act governing the obligation to file a post-effective amendment
permit, in lieu of filing a post-effective amendment which (A) includes any
prospectus required by Section 10(a)(3) of the Act or (B) reflects facts or
events representing a material or fundamental change in the information set
forth in the registration statement, the incorporation by reference of
information required to be included in (A) and (B) above to be contained in
periodic reports filed pursuant to Section 13 or 15(d) of the 1934 Act into the
registration statement.

                  (b) Prepare and file with the SEC such amendments and
supplements to such registration statement and the prospectus used in connection
with such registration statement as may be necessary to comply with the
provisions of the Act with respect to the disposition of all securities covered
by such registration statement.

                  (c) Furnish to the Holders such numbers of copies of a
prospectus, including a preliminary prospectus and any amendment or supplement
to the prospectus, in conformity with the requirements of the Act, and such
other documents as they may reasonably request in order to facilitate the
disposition of Registrable Securities owned by them.

                  (d) Use its commercially reasonable efforts to register and
qualify the securities covered by such registration statement under such other
securities or Blue Sky laws of such jurisdictions as shall be reasonably
requested by the Holders; provided that the Company


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shall not be required in connection therewith or as a condition thereto to
qualify to do business or to file a general consent to service of process in any
such states or jurisdictions.

                  (e) Use its commercially reasonable efforts to furnish on the
date that such Registrable Securities are delivered to the underwriters for sale
in connection with a registration pursuant to this Section 1, if such securities
are being sold through underwriters, or, if such securities are not being sold
through underwriters, on the date that the registration statement with respect
to such securities becomes effective, (i) an opinion, dated such date, of the
counsel representing the Company for the purposes of such registration, in form
and substance as is customarily given to underwriters in an underwritten public
offering, addressed to the underwriters, if any, and to the Holders of
Registrable Securities and (ii) a letter dated such date, from the independent
certified public accountants of the Company, in form and substance as is
customarily given by independent certified public accountants to underwriters in
an underwritten public offering, addressed to the underwriters, if any, and to
the Holders of Registrable Securities.

                  (f) In the event of any underwritten public offering, enter
into and perform its obligations under an underwriting agreement, in usual and
customary form, with the managing underwriter of such offering. Each Holder
participating in such underwriting shall also enter into and perform its
obligations under such an agreement.

                  (g) Notify each Holder of Registrable Securities covered by
such registration statement at any time when a prospectus relating thereto is
required to be delivered under the Act of the happening of any event as a result
of which the prospectus included in such registration statement, as then in
effect, includes an untrue statement of a material fact or omits to state a
material fact required to be stated therein or necessary to make the statements
therein not misleading in the light of the circumstances then existing, and
prepare a supplement or amendment to such prospectus so that, as thereafter
delivered to the purchasers of such Registrable securities, such prospectus will
not contain an untrue statement of a material fact or omit to state any fact
necessary to make the statements therein not misleading.

                  (h) Cause all such Registrable Securities registered pursuant
hereunder to be listed on each securities exchange on which similar securities
issued by the Company are then listed.

                  (i) Provide a transfer agent and registrar for all Registrable
Securities registered pursuant hereto and a CUSIP number for all such
Registrable Securities, in each case not later than the effective date of such
registration.

                  (j) In the event of the issuance of any stop order suspending
the effectiveness of the registration statement, or of any order suspending or
preventing the use of any related prospectus or suspending the qualification of
any Registrable Securities included in such registration statement for sale in
any jurisdiction, use its reasonable efforts promptly to obtain the withdrawal
of such order.


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                  (k) Maintain eligibility to use Form S-3 or any similar short
form registration statement by filing with the SEC in a timely manner all
reports and other documents required of the Company under the Act and the 1934
Act.

            1.4 FURNISH INFORMATION. It shall be a condition precedent to the
obligations of the Company to take any action pursuant to this Section 1 with
respect to the Registrable Securities of any selling Holder that such Holder
shall furnish to the Company such information regarding itself, the Registrable
Securities held by it, and the intended method of disposition of such securities
as shall be required by law to effect the registration of such Holder's
Registrable Securities.

            1.5 DELAY OF REGISTRATION. No Holder shall have any right to obtain
or seek an injunction restraining or otherwise delaying any such registration as
the result of any controversy that might arise with respect to the
interpretation or implementation of this Section 1.

            1.6 INDEMNIFICATION. In the event any Registrable Securities are
included in a registration statement under this Section 1:

                  (a) To the extent permitted by law, the Company will indemnify
and hold harmless each Holder, any underwriter (as defined in the Act) for such
Holder and each person, if any, who controls such Holder or underwriter within
the meaning of the Act or the 1934 Act, against any losses, claims, damages, or
liabilities (joint or several) to which they may become subject under the Act,
or the 1934 Act or other federal or state law, insofar as such losses, claims,
damages, or liabilities (or actions in respect thereof) arise out of or are
based upon any of the following statements, omissions or violations
(collectively a "Violation"): (i) any untrue statement or alleged untrue
statement of a material fact contained in such registration statement, including
any preliminary prospectus or final prospectus contained therein or any
amendments or supplements thereto, (ii) the omission or alleged omission to
state therein a material fact required to be stated therein, or necessary to
make the statements therein not misleading, or (iii) any violation or alleged
violation by the Company of the Act, the 1934 Act or any rule or regulation
promulgated under the Act or the 1934 Act; and the Company will pay to each such
Holder, underwriter or controlling person any legal or other expenses reasonably
incurred by them in connection with investigating or defending any such loss,
claim, damage, liability, or action; provided, however, that the indemnity
agreement contained in this subsection 1.6(a) shall not apply to amounts paid in
settlement of any such loss, claim, damage, liability, or action if such
settlement is effected without the consent of the Company (which consent shall
not be unreasonably withheld), nor shall the Company be liable in any such case
for any such loss, claim, damage, liability, or action to the extent that it
arises out of or is based upon a Violation which occurs in reliance upon and in
conformity with written information furnished expressly for use in connection
with such registration by any such Holder, underwriter or controlling person.

                  (b) To the extent permitted by law, each selling Holder will
indemnify and hold harmless the Company, each of its directors, each of its
officers who has signed the registration statement, each person, if any, who
controls the Company within the meaning of the Act, any underwriter, any other
Holder selling securities in such registration statement and any


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controlling person of any such underwriter or other Holder, against any losses,
claims, damages, or liabilities (joint or several) to which any of the foregoing
persons may become subject, under the Act, the 1934 Act or other federal or
state law, insofar as such losses, claims, damages, or liabilities (or actions
in respect thereto) arise out of or are based upon any Violation, in each case
to the extent (and only to the extent) that such Violation occurs in reliance
upon and in conformity with written information furnished by such Holder
expressly for use in connection with such registration; and each such Holder
will pay, as incurred, any legal or other expenses reasonably incurred by any
person intended to be indemnified pursuant to this subsection 1.6(b), in
connection with investigating or defending any such loss, claim, damage,
liability, or action; provided, however, that the indemnity agreement contained
in this subsection 1.6(b) shall not apply to amounts paid in settlement of any
such loss, claim, damage, liability or action if such settlement is effected
without the consent of the Holder, which consent shall not be unreasonably
withheld; provided, that, in no event shall any indemnity under this subsection
1.6(b) exceed the net proceeds from the offering received by such Holder, unless
such liability arises out of or is based on the willful misconduct or fraud by
such Holder.

                  (c) Promptly after receipt by an indemnified party under this
Section 1.6 of notice of the commencement of any action (including any
governmental action), such indemnified party will, if a claim in respect thereof
is to be made against any indemnifying party under this Section 1.6, deliver to
the indemnifying party a written notice of the commencement thereof and the
indemnifying party shall have the right to participate in, and, to the extent
the indemnifying party so desires, jointly with any other indemnifying party
similarly noticed, to assume the defense thereof with counsel mutually
satisfactory to the parties; provided, however, that an indemnified party
(together with all other indemnified parties which may be represented without
conflict by one counsel) shall have the right to retain one separate counsel,
with the fees and expenses to be paid by the indemnifying party, if
representation of such indemnified party by the counsel retained by the
indemnifying party would be inappropriate due to actual or potential differing
interests between such indemnified party and any other party represented by such
counsel in such proceeding. The failure to deliver written notice to the
indemnifying party within a reasonable time of the commencement of any such
action, if prejudicial to its ability to defend such action, shall relieve such
indemnifying party of any liability to the indemnified party under this Section
1.6, but the omission so to deliver written notice to the indemnifying party
will not relieve it of any liability that it may have to any indemnified party
otherwise than under this Section 1.6.

                  (d) If the indemnification provided for in this Section 1.6 is
held by a court of competent jurisdiction to be unavailable to an indemnified
party with respect to any loss, liability, claim, damage, or expense referred to
therein, then the indemnifying party, in lieu of indemnifying such indemnified
party hereunder, shall contribute to the amount paid or payable by such
indemnified party as a result of such loss, liability, claim, damage, or expense
in such proportion as is appropriate to reflect the relative fault of the
indemnifying party on the one hand and of the indemnified party on the other in
connection with the statements or omissions that resulted in such loss,
liability, claim, damage, or expense as well as any other relevant equitable
considerations. The relative fault of the indemnifying party and of the
indemnified party shall be determined by reference to, among other things,
whether the untrue or alleged untrue statement of a material fact or the
omission to state a material fact relates to information supplied by the


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indemnifying party or by the indemnified party and the parties' relative intent,
knowledge, access to information, and opportunity to correct or prevent such
statement or omission.

                  (e) Notwithstanding the foregoing, to the extent that the
provisions on indemnification and contribution contained in the underwriting
agreement entered into in connection with the underwritten public offering are
in conflict with the foregoing provisions, the provisions in the underwriting
agreement shall control.

                  (f) The obligations of the Company and Holders under this
Section 1.6 shall survive the completion of any offering of Registrable
Securities in a registration statement under this Section 1, and otherwise.

            1.7 ASSIGNMENT OF REGISTRATION RIGHTS. The rights to have the
Registrable Securities registered pursuant to this Section 1 may be assigned
(but only with all related obligations) by a Holder to a transferee or assignee
of such securities who, after such assignment or transfer, holds at least 25% of
then outstanding shares of Registrable Securities (subject to appropriate
adjustment for stock splits, stock dividends, combinations and other
recapitalizations), provided: (a) the Company is, within a reasonable time after
such transfer, furnished with written notice of the name and address of such
transferee or assignee and the securities with respect to which such
registration rights are being assigned; (b) such transferee or assignee agrees
in writing to be bound by and subject to the terms and conditions of this
Agreement; and (c) such assignment shall be effective only if immediately
following such transfer the further disposition of such securities by the
transferee or assignee is restricted under the Act. For the purposes of
determining the number of shares of Registrable Securities held by a transferee
or assignee, the holdings of transferees and assignees of: (i) a partnership who
are partners or retired partners of such partnership; or (ii) a limited
liability company who are members of such limited liability company (including
spouses and ancestors, lineal descendants and siblings of such partners, members
or spouses who acquire Registrable Securities by gift, will or intestate
succession) shall be aggregated together and with the partnership or limited
liability company; provided that all assignees and transferees who would not
qualify individually for assignment of registration rights shall have a single
attorney-in-fact for the purpose of exercising any rights, receiving notices or
taking any action under this Section 1.

      2. MISCELLANEOUS.

            2.1 SUCCESSORS AND ASSIGNS. Except as otherwise provided herein, the
terms and conditions of this Agreement shall inure to the benefit of and be
binding upon the respective successors and assigns of the parties (including
transferees of any shares of Registrable Securities). Nothing in this Agreement,
express or implied, is intended to confer upon any party other than the parties
hereto or their respective successors and assigns any rights, remedies,
obligations, or liabilities under or by reason of this Agreement, except as
expressly provided in this Agreement.

            2.2 GOVERNING LAW. This Agreement shall be governed by and construed
under the laws of the State of Delaware as applied to agreements among Delaware
residents entered into and to be performed entirely within Delaware.


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            2.3 SUBMISSION TO JURISDICTION; WAIVERS. Each of the parties hereto
irrevocably agrees that any legal action or proceeding with respect to this
Agreement or for the recognition and enforcement of any judgment in respect
hereof brought by the other party hereto or its successors or assigns will be
brought and determined in the courts of the State of Delaware, and each of the
parties hereby irrevocably submits with regard to any such action or proceeding
for itself and in respect to its property, generally and unconditionally, to the
exclusive jurisdiction of the aforesaid courts. Each of the parties hereto
hereby irrevocably waives, and agrees not to assert, by way of motion, as a
defense, counterclaim or otherwise, in any action or proceeding with respect to
this Agreement, (a) any claim that it is not personally subject to the
jurisdiction of the above-named courts for any reason other than the failure to
lawfully serve process, (b) that it or its property is exempt or immune from
jurisdiction of any such court or from any legal process commenced in such
courts (whether through service of notice, attachment prior to judgment,
attachment in aid of execution of judgement, execution of judgment or
otherwise), (c) to the fullest extent permitted by applicable law, that (i) the
suit, action or proceeding in any such court is brought in an inconvenient
forum, (ii) the venue of such suit, action, or proceeding is improper and (iii)
this Agreement, or the subject matter hereof, may not be enforced in or by such
courts and (d) any right to trial by jury.

            2.4 COUNTERPARTS. This Agreement may be executed in two or more
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.

            2.5 TITLES AND SUBTITLES. The titles and subtitles used in this
Agreement are used for convenience only and are not to be considered in
construing or interpreting this Agreement.

            2.6 NOTICES. All notices and other communications required or
permitted hereunder shall be in writing and shall be deemed effectively given:
(a) upon personal delivery to the party to be notified, (b) when sent by
confirmed telex or facsimile if sent during normal business hours of the
recipient or, if not sent during normal business hours, then on the next
business day, (c) three days after having been sent by registered or certified
mail, return receipt requested, postage prepaid, or (d) one day after deposit
with a nationally recognized overnight courier, specifying next day delivery,
with written verification of receipt. All communications shall be sent to the
addresses set forth in the Purchase Agreement for each party or at such other
address as such party may designate by 10 days advance written notice to the
other parties hereto.

            2.7 EXPENSES. If any action at law or in equity is necessary to
enforce or interpret the terms of this Agreement, the prevailing party shall be
entitled to reasonable attorneys' fees, costs and necessary disbursements in
addition to any other relief to which such party may be entitled.

            2.8 AMENDMENTS AND WAIVERS. Any term of this Agreement may be
amended and the observance of any term of this Agreement may be waived (either
generally or in a particular instance and either retroactively or
prospectively), only with the written consent of the Company and the holders of
a majority of the Registrable Securities then outstanding. Any amendment or
waiver effected in accordance with this paragraph shall be binding upon each


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holder of any Registrable Securities then outstanding, each future holder of all
such Registrable Securities, and the Company.

            2.9 SEVERABILITY. If one or more provisions of this Agreement are
held to be unenforceable under applicable law, such provision shall be excluded
from this Agreement and the balance of the Agreement shall be interpreted as if
such provision were so excluded and shall be enforceable in accordance with its
terms.

            2.10 AGGREGATION OF STOCK. All shares of Registrable Securities held
or acquired by affiliated entities or persons shall be aggregated together for
the purpose of determining the availability of any rights under this Agreement.

            2.11 ENTIRE AGREEMENT; AMENDMENT; WAIVER. This Agreement (including
the Exhibits hereto, if any) constitutes the full and entire understanding and
agreement between the parties with regard to the subjects hereof and thereof.


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      IN WITNESS WHEREOF, the parties have executed this Agreement as of the
date first above written.

                                            ENDOCARE, INC.


                                            By:      /s/ PAUL MIKUS
                                               ---------------------------------
                                            Name:    Paul Mikus
                                                 -------------------------------
                                            Title:   CEO
                                                  ------------------------------


                                            CRYOMEDICAL SCIENCES, INC.


                                            By:      /s/ J. ANDREW GREULING
                                               ---------------------------------
                                            Name:    J. Andrew Greuling
                                                 -------------------------------
                                            Title:   President & CEO
                                                  ------------------------------


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