V.3.6.2 Coding for Solid Tumors

Grade, Differentiation (Codes 1, 2, 3, 4, 9)

Note: These rules are hierarchical.

Coding Instructions:

Systemic treatment and radiation can alter a tumor’s grade. Therefore, it is important to code grade based on information prior to neoadjuvant therapy even if grade is unknown.
Code the grade from the primary tumor only.

Do NOT code grade based on metastatic tumor or recurrence. In the rare instance that tumor tissue extends contiguously to an adjacent site and tissue from the primary site is not available, code grade from the contiguous site.
If primary site is unknown, code grade to 9.

Code the grade shown below (6th digit) for specific histologic terms that imply a grade.

Carcinoma, undifferentiated (8020/34).
Carcinoma, anaplastic (8021/34).
Follicular adenocarcinoma, well differentiated (8331/31).
Thymic carcinoma, well differentiated (8585/31).
Sertoli-Leydig cell tumor, poorly differentiated (8631/33).
Sertoli-Leydig cell tumor, poorly differentiated with heterologous elements (8634/33) Undifferentiated sarcoma (8805/34).
Liposarcoma, well differentiated (8851/31).
Seminoma, anaplastic (9062/34).
Malignant teratoma, undifferentiated (9082/34).
Malignant teratoma, intermediate type (9083/32).
Intraosseous osteosarcoma, well differentiated (9187/31) Astrocytoma, anaplastic (9401/34).
Oligodendroglioma, anaplastic (9451/34).
Retinoblastoma, differentiated (9511/31).
Retinoblastoma, undifferentiated (9512/34).

In situ and/or combined in situ/invasive components:

If a grade is given for an in situ tumor, code it. Do NOT code grade for dysplasia such as high grade dysplasia.
If there are both in situ and invasive components, code only the grade for the invasive portion even if its grade is unknown.

If there is more than one grade, code the highest grade within the applicable system. Code the highest grade even if it is only a focus. Code grade in the following priority order using the first applicable system:

special grade systems for the sites listed in Coding for Solid Tumors #6.
differentiation: use Coding for Solid Tumors #7: 2-, 3-, or 4- grade system.
nuclear grade: use Coding for Solid Tumors #7: 2-, 3-, or 4- grade system.
If it isn’t clear whether it is a differentiation or nuclear grade and a 2-, 3-, or 4- grade system was used, code it.
Terminology (use Coding for Solid Tumors #8).

Use the information from the special grade systems first. If no special grade can be coded, continue with Coding for Solid Tumors #7-9.

Special grade systems for solid tumors:

Breast, prostate, heart, mediastinum, peritoneum, retroperitoneum, soft tissue, and kidney parenchyma is have special grade systems. For these sites, use the Special Grade System Rules sections (linked below):

CS Schema	Special Grade System
Breast	Nottingham or Bloom-Richardson (BR) Score/Grade, see Section V.3.6.4
Prostate	Gleason's Score on Needle Core Biopsy/Transurethral Resection of Prostate (TURP), see Section V.3.6.7
Prostate	Gleason's Score on Prostatectomy/Autopsy, see Section V.3.6.7
Heart, Mediastinum	Grade for Sarcomas, see Section V.3.6.6
Peritoneum	Grade for Sarcomas, see Section V.3.6.6
Retroperitoneum	Grade for Sarcomas, see Section V.3.6.6
Soft Tissue	Grade for Sarcomas, see Section V.3.6.6
Kidney Parenchyma	Fuhrman Nuclear Grade, see Section V.3.6.5

Notes:

Do not use these tables to code grade for any other groups including WHO (CNS tumors), WHO/ISUP (bladder, renal pelvis), or FIGO (female gynecologic sites) grades.
WHO grades are NOT to be used in the 6th digit morphology position.
If only a WHO grade is given, code grade (6th digit) to 9 (unknown).

Use the Two-, Three- or Four-grade system information

Two-grade system.

Term	Description	Grade Code	Exception For Breast and Prostate Grade Code
1/2, I/II	Low grade	2	1
2/2, II/II	High grade	4	3

In transitional cell carcinoma for bladder, the terminology high grade TCC and low grade TCC are coded in the two-grade system.

Three-grade system.

Term	Description	Grade Code	Exception For Breast and Prostate Grade Code
1/3	Low grade	2	1
2/3	Intermediate grade	3	2
3/3	High grade	4	3

Four-grade system: Any four-grade system including Edmondson and Steiner grade for liver.

Term	Description	Grade Code
1/4	Grade I; Well differentiated	1
2/4	Grade II; Moderately differentiated	2
3/4	Grade III; Poorly differentiated	3
4/4	Grade IV; Undifferentiated	4

Terminology: use the ‘Description’ column or the ‘Grade’ column to code grade. Breast & Prostate use the same grade code with a few noted exceptions.

Description	Grade	Assign Grade Code	Exception For Breast and Prostate Grade Code
Differentiated, NOS	I	1
Well differentiated	I	1
Only stated as ‘Grade I’	I	1

Fairly well differentiated	II	2
Intermediate differentiation	II	2
Low grade	I-II	2	1
Mid differentiated	II	2
Moderately differentiated	II	2
Moderately well differentiated	II	2
Partially differentiated	II	2
Partially well differentiated	I-II	2	1
Relatively or generally well differentiated	II	2
Only stated as ‘Grade II’	II	2
Medium grade, intermediate grade	I-III	3	2
Moderately poorly differentiated	III	3
Moderately undifferentiated	III	3
Poorly differentiated	III	3
Relatively poorly differentiated	III	3
Relatively undifferentiated	III	3
Slightly differentiated	III	3
Dedifferentiated	III	3
Only stated as ‘Grade III’	III	3
High grade	III-IV	4	3
Undifferentiated, anaplastic, not differentiated	IV	4
Only stated as ‘Grade IV’	IV	4
Non-high grade		9

If no description fits or grade is unknown prior to neoadjuvant therapy, code as a 9 (unknown).

For Special Grade System Rules see:

V.3.6.3 Hematopoietic and Lymphoid Neoplasms.
V.3.6.4 Breast – Nottingham or Bloom-Richardson (BR) Score/Grade.
V.3.6.5 Kidney Parenchyma - Fuhrman Nuclear Grade.
V.3.6.6 Soft Tissue - Grade for Sarcomas.
V.3.6.7 Prostate – Gleason Score.

<< Prev. Next >>