All neoplasms are classified in this chapter, whether they are functionally active or not. An additional code from Chapter 4 may be used, to identify functional activity associated with any neoplasm.
Chapter 2 classifies neoplasms primarily by site (topography), with broad groupings for behavior, malignant, in situ, benign, etc. The Table of Neoplasms should be used to identify the correct topography code. In a few cases, such as for malignant melanoma and certain neuroendocrine tumors, the morphology (histologic type) is included in the category and codes.
Primary malignant neoplasms overlapping site boundaries
A primary malignant neoplasm that overlaps two or more contiguous (next to each other) sites should be classified to the subcategory/code .8 ('overlapping lesion'), unless the combination is specifically indexed elsewhere. For multiple neoplasms of the same site that are not contiguous, such as tumors in different quadrants of the same breast, codes for each site should be assigned.
Malignant neoplasm of ectopic tissue
Malignant neoplasms of ectopic tissue are to be coded to the site mentioned, e.g., ectopic pancreatic malignant neoplasms are coded to pancreas, unspecified (C25.9).
Malignant neoplasms (C00-C96)
Malignant neoplasms, stated or presumed to be primary (of specified sites), and certain specified histologies, except neuroendocrine, and of lymphoid, hematopoietic and related tissue (C00-C75)
Malignant neoplasms of lip, oral cavity and pharynx (C00-C14)
Malignant neoplasms of digestive organs (C15-C26)
Malignant neoplasms of respiratory and intrathoracic organs (C30-C39)
Malignant neoplasms of bone and articular cartilage (C40-C41)
Melanoma and other malignant neoplasms of skin (C43-C44)
Malignant neoplasms of mesothelial and soft tissue (C45-C49)
Malignant neoplasms of breast (C50)
Malignant neoplasms of female genital organs (C51-C58)
Malignant neoplasms of male genital organs (C60-C63)
Malignant neoplasms of urinary tract (C64-C68)
Malignant neoplasms of eye, brain and other parts of central nervous system (C69-C72)
Malignant neoplasms of thyroid and other endocrine glands (C73-C75)
Malignant neuroendocrine tumors (C7A)
Secondary neuroendocrine tumors (C7B)
Malignant neoplasms of ill-defined, other secondary and unspecified sites (C76-C80)
Malignant neoplasms of lymphoid, hematopoietic and related tissue (C81-C96)
In situ neoplasms (D00-D09)
Benign neoplasms, except benign neuroendocrine tumors (D10-D36)
Benign neuroendocrine tumors (D3A)
Neoplasms of uncertain behavior, polycythemia vera and myelodysplastic syndromes (D37-D48)
Neoplasms of unspecified behavior (D49)