§ 81.23 — Guidelines For Cancers For Which Primary Site Is Unknown

(a) In claims for which the primary cancer site cannot be determined, but a site of metastasis is known, DOL will calculate probability of causation estimates for various likely primary sites. Table 1 of this paragraph (a) indicates the primary cancer site(s) DOL will use in NIOSH-IREP when the primary cancer site is unknown.

Primary cancers (ICD-10-CM codes) for which probability of causation is to be calculated, if only a secondary cancer site is known. “M” indicates cancer site should be used for males only, and “F” indicates the cancer site should be used for females only.

(b) DOL will select the site producing the highest estimate for probability of causation to adjudicate the claim.