; (ii) the public safety officer began serving as a public safety officer not later than 5 years before the date of the diagnosis of the public safety officer with an exposure-related cancer; (iii) the public safety officer was diagnosed with an exposure-related cancer not later than 15 years after the last date of active service as a public safety officer of the public safety officer; and (iv) the exposure-related cancer directly and proximately results in the death or permanent and total disability of the public safety officer. (B) Exception The presumption under subparagraph (A) shall not apply to the death or permanent and total disability of a public safety officer due to an exposure-related cancer if competent medical evidence establishes that the exposure-related cancer was unrelated to the exposure or contact described in subparagraph (A)(i). (3) Additional exposure-related cancers (A) In general The Director shall— (i) periodically review the definition of exposure-related cancer under paragraph (1)