Protecting Access to Lifesaving Screenings Act (PALS Act) of 2017 This bill requires that any provision of law referring to current recommendations of the U.S. Preventive Services Task Force (USPSTF) with respect to breast cancer screening, mammography, and prevention be administered as if: (1) the provision referred to USPSTF recommendations last issued before 2009; and (2) those recommendations applied to any screening mammography modality, including any digital modality of such a procedure. (In 2009, the USPSTF updated its guidelines to recommend against routine screening mammography for women between 40 to 49 years of age and to recommend biennial, instead of annual, screening mammography for most women between 50 to 74 years of age.) This requirement shall also apply to the Veterans Health Administration's policy on mammography screening for veterans. In addition, the bill amends title XVIII (Medicare) of the Social Security Act to preserve Medicare coverage for screening mammography, without a requirement for coinsurance, and expand the definition of screening mammography to include any digital modality of such a procedure. The Centers for Medicare & Medicaid Services may not decrease the frequency with which screening mammography may be paid by Medicare for a woman over 39 years of age.