Field Length: 1
Enter the one digit code which describes this primary with regard to involvement of one or both sides of paired organs (see list below).
Not a paired site
Right: origin of primary
Left: origin of primary
Only one side involved, right or left origin unspecified
Bilateral involvement at time of diagnosis, lateral origin unknown for a single primary; or both ovaries involved simultaneously, single histology; bilateral retinoblastoma; bilateral Wilms tumors
Paired site: Midline tumor (effective with 01/01/2010 dx)
Paired site, but no information concerning laterality
1. Use code 0 (not a paired organ) when:
a. The primary site is not a paired site
b. Primary site is unknown primary site (C80.9)
c. Laterality is unknown for a death certificate only (DCO) case and the primary site is NOT one of the primary site codes listed in the table below: (Sites for Which Laterality Codes Must Be Recorded)
2. Code laterality using codes 1-9 for all of the sites listed in the table: (Sites for Which Laterality Codes Must Be Recorded)
a. Laterality may be coded for sites other than those required, for example, Thyroid
3. Code the side where the primary tumor originated.
a. Assign code 3 if the laterality is not known but the tumor is confined to a single side of the paired organ.
Example: Pathology report: Patient has a 2cm carcinoma in the upper pole of the kidney. Code laterality as 3 because there is documentation that the disease exists in only one kidney, but it is unknown if the disease originated in the right or left kidney.
4. Code 4 is seldom used EXCEPT for the following:
a. Both ovaries involved simultaneously with a single histology, or epithelial histologies (8000-8799)
b. Diffuse bilateral lung nodules
c. Bilateral retinoblastomas
d. Bilateral Wilms tumors
5. Assign code 5 when the tumor originates in the midline of a site listed in 5.a
a. C700, C710-C714, C722-C725, C443, C444, C445
i. Do not assign code 5 to sites not listed in 5.a
Example 1: Patient has an excision of a melanoma located just above the umbilicus (C445, laterality code 5).
Example 2: Patient has a midline meningioma of the cerebral meninges (C700, laterality code 5).
6. Assign code 9 when:
a. The neoplasm originated in a paired site and
i. Laterality is unknown, AND
ii. There is no statement that only one side of the paired organ is involved
Example 1: Admitting history says patient was diagnosed with lung cancer based on positive sputum cytology. Patient is treated for painful bony metastases. There is no information about laterality in the diagnosis of this lung cancer.
Example 2: Widely metastatic ovarian carcinoma surgically debulked. Ovaries could not be identified in the specimen.
b. Laterality is unknown for a death certificate only (DCO) case with primary site code listed in the table below (Sites for Which Laterality Codes Must Be Recorded)
7. Document the laterality in a text field
Sites for Which Laterality Codes Must Be Recorded
Starting with cases diagnosed January 1, 2004 and later, laterality is coded for select invasive, benign, and borderline primary intracranial and CNS tumors.
A laterality code other than 0 must be assigned for the sites listed in the table below. There is an effective date for assigning laterality for some of the sites. If the site is not listed on the table, code 0 may be assigned for laterality. Laterality may be coded for sites other than those required below. For example: Code 2 may be assigned for a tumor originating in the left lobe of thyroid.
Note: Laterality will be automatically coded to 0 in SEER*DMS for sites not listed in the table below.
Site or Subsite
Overlapping lesion of tonsil
Long bones of upper limb and scapula
Short bones of upper limb
Long bones of lower limb
Short bones of lower limb
Skin of eyelid
Skin of external ear
Skin of other and unspecified parts of face (if midline, code 5)
|C44.4||Skin of scalp and neck|
Skin of trunk (if midline, code 5)
Skin of arm and shoulder
Skin of leg and hip
Peripheral nerves and autonomic nervous system of upper limb and shoulder
Peripheral nerves and autonomic nervous system of lower limb and hip
Connective, subcutaneous, and other soft tissue of upper limb and shoulder
Connective, subcutaneous, and other soft tissue of lower limb and hip
Breast (male and female)
Eye and lacrimal gland
Cranial nerve, NOS