(a) DOL will calculate probability of causation for all cancers, except chronic lymphocytic leukemia as provided under Sec. 81.30, using NIOSH-IREP.
(b) Carcinoma in situ (ICD-9 codes 230-234), neoplasms of uncertain behavior (ICD-9 codes 235-238), and neoplasms of unspecified nature (ICD-9 code 239) are assumed to be malignant, for purposes of estimating probability of causation.
(c) All secondary and unspecified cancers of the lymph node (ICD-9 code 196) shall be considered secondary cancers (cancers resulting from metastasis of cancer from a primary site). For claims identifying cancers of the lymph node, Table 1 in Sec. 81.23 provides guidance for assigning a primary site and calculating probability of causation using NIOSH-IREP.