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                                                                    EXHIBIT 23.1

                          INDEPENDENT AUDITORS' CONSENT

     We consent to the incorporation by reference in Registration Statements
Nos. 333-22675, 333-59291, 333-82925, 333-38644, 333-59172, 333-64360,
333-64362 and 333-88764 on Form S-8 of Cytyc Corporation of our
report dated January 27, 2004 (which report expresses an unqualified opinion and
includes an explanatory paragraph describing a change in accounting principle
with respect to goodwill in the year ended December 31, 2002 and certain
revisions, resulting from the change in accounting principle, to disclosures in
the financial statements for the year ended December 31, 2001 which were audited
by other auditors, as disclosed in Note 2 to the consolidated financial
statements), relating to the consolidated financial statements of Cytyc
Corporation as of and for the years ended December 31, 2003 and 2002, appearing
in this Annual Report on Form 10-K of Cytyc Corporation for the year ended
December 31, 2003.


/s/ Deloitte & Touche LLP

Boston, Massachusetts
January 30, 2004