Improved Quality of Treatment Decisions. We believe our approach to genomic-based cancer analysis improves the quality of cancer treatment decisions by providing an individualized analysis of each patients tumor that is correlated to clinical outcome. Our approach represents a substantial departure from existing approaches to treatment, which often use subjective, anatomic and qualitative factors to determine treatments. Oncotype DX has been shown in clinical studies to classify many patients into recurrence risk categories different from classifications based on current guidelines. Thus, our solution enables patients and physicians to make more informed decisions about treatment risk-benefit and, consequently, design an individualized treatment plan

Exhibit 10.4.2

AMENDMENT TO SUBLEASE

     THIS AMENDMENT TO SUBLEASE (“Amendment”) is entered into as of October 29, 2003 between Corixa Corporation and its affiliates, a Delaware corporation (“Tenant”) and Genomic Health, Inc., a Delaware corporation (“Subtenant”).

Recitals

     A. The predecessor in interest of Tenant and the predecessor in interest of Metropolitan Life Insurance Company, a New York corporation (“Landlord”), have entered into that certain lease dated January 3, 1992, as amended by (i) that certain First Amendment dated January 5, 1993, (ii) that certain Second Amendment dated January 10, 1995, (iii) that certain Third Amendment dated March 24, 1995, (iv) that certain holdover letter agreement dated February 12, 1999, (v) that certain Fifth Amendment dated February 26, 1999 and (vi) that certain Sixth Amendment dated September 29, 2000 (collectively referred to herein as the “Lease”), whereby Landlord leases to Tenant that certain premises in Building 11 of Phase II, with the current street address of 301 Penobscot Drive, Redwood City, CA, (“Premises”).

     B. Tenant and Subtenant entered into a sublease dated June 1, 2001 (the “Existing Sublease”), respecting a portion of the Premises (the “Sublease Premises”). Capitalized terms not otherwise defined herein shall have the meanings set forth in the Existing Sublease. The term “Sublease Agreement” shall mean the Existing Sublease as amended hereby.

     C. Tenant and Subtenant wish to hereby modify certain terms and provisions under the Sublease Agreement and are executing this Amendment to effectuate said modifications.

     NOW, THEREFORE, in consideration of the covenants set forth herein, Tenant and Subtenant hereby agree as follows:

     2. Rent. Section 2.1 of the Existing Sublease is hereby revised to provide that commencing as of October 1, 2003 and continuing through the New Expiration Date, the Rent for the Sublease Premises shall be in the amount of $74,838 per month. The Rent as so revised shall continue to be the total monthly amount due to Tenant for rental of the Sublease Premises.

     3. Consent of Landlord. This Amendment is subject to the written consent of Landlord in accordance with the terms of the Lease, which consent, Tenant shall diligently pursue, at no cost to Subtenant.

     4. Counterparts. This Amendment may be executed in counterparts, each of which shall be an original, but all of which shall constitute one and the same Amendment.

     5. Confirmation of Existing Sublease Agreement. Except as amended by this Amendment, the Existing Sublease is unmodified, and as amended hereby, the Sublease Agreement remains in full force and effect.

     IN WITNESS WHEREOF, Tenant and Subtenant have executed this Amendment as of the date first above written.

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