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Filed Pursuant to Rule 497(e)
Registration File No.: 33-53955
SUPPLEMENT TO THE PROSPECTUS
OF MORGAN STANLEY DEAN WITTER MID-CAP GROWTH FUND
DATED JULY 29, 1998
On February 25, 1999, the Board of Trustees of Morgan Stanley Dean Witter
Mid-Cap Growth Fund (the "Fund") approved an Agreement and Plan of
Reorganization by and between the Fund and TCW/DW Mid-Cap Equity Trust
("Mid-Cap Equity"), pursuant to which substantially all of the assets of the
Fund would be combined with those of Mid-Cap Equity and shareholders of the
Fund would become shareholders of Mid-Cap Equity receiving shares of Mid-Cap
Equity equal to the value of their holdings in the Fund (the "Reorganization").
Each shareholder of the Fund will receive the class of shares of Mid-Cap Equity
that corresponds to the class of shares of the Fund currently held by that
shareholder. The Reorganization is subject to the approval of shareholders of
the Fund at a special meeting of shareholders scheduled to be held on June 8,
1999 and is also contingent upon approval of certain separate proposals being
submitted to shareholders of Mid-Cap Equity to approve a new investment
management agreement with Morgan Stanley Dean Witter Advisors and sub-advisory
agreement with TCW Funds Management, Inc. for that Fund. In connection with
these new agreements, Mid-Cap Equity will become a member of the Morgan Stanley
Dean Witter family of funds and its name will be changed to Morgan Stanley Dean
Witter Mid-Cap Equity Trust. A Proxy Statement formally detailing the proposal,
the reasons for the Trustees' action and information concerning Mid-Cap Equity
will be distributed to shareholders of the Fund.
February 25, 1999
