Data Last Updated: Dec. 17, 2025

Grade Post Therapy Clin (yc)

Notes

**Note 1:** Leave Grade Post Therapy Clin (yc) blank when * No neoadjuvant therapy * Clinical or pathological case only * Neoadjuvant therapy completed, no microscopic exam is done prior to surgery/resection of primary tumor * There is only one grade available and it cannot be determined if it is clinical, pathological, post therapy clinical or post therapy pathological **Note 2:** Assign the highest grade from the microscopically sampled specimen of the primary site following neoadjuvant therapy or primary systemic/radiation therapy. **Note 3:** If there are multiple tumors with different grades abstracted as one primary, code the highest grade. **Note 4:** Codes 1-3 take priority over codes A-D. * Grades A-D should only be used in the absence of a physician's statement of grade (G1, G2, G3) or no results for Ki-67 or Mitotic Count (See also Note 6) **Note 5:** Do not code grade based on the following terminology: * Neuroendocrine carcinoma, low grade (8240/3) * Neuroendocrine carcinoma, well differentiated (8240/3) * Neuroendocrine carcinoma, moderately differentiated (8249/3) * Poorly differentiated neuroendocrine carcinoma (8246/3) **Note 6:** Code grade based on the physician's documentation (G1, G2, G3) OR **in the absence of a physician's statement,** code grade based on the Ki-67 and Mitotic Count. * If a Ki-67 is documented as less than 3, many times the mitotic count is not done. In this situation, the Ki-67 alone is enough to code the grade (G1). * Grades 2 and 3, are either/or for Ki-67 and Mitotic Count. You do not need both the Ki-67 and Mitotic Count to assign grade 2 or 3. **Note 7:** Code 9 (unknown) when * Microscopic exam is done after neoadjuvant therapy and grade from the primary site is not documented * Microscopic exam is done after neoadjuvant therapy and there is no residual cancer * Grade checked “not applicable” on CAP Protocol (if available) and no other grade information is available
Code Description
1 G1: Mitotic count (per 2mm2) less than 2 AND
Ki-67 index (%) less than 3

Stated as WHO Grade 1
2 G2: Mitotic count (per 2mm2) equal 2-20 OR
Ki-67 index (%) equal 3-20

Stated as WHO Grade 2
3 G3: Mitotic count (per 2mm2) greater than 20 OR
Ki-67 index (%) greater than 20

Stated as WHO Grade 3
A Well differentiated
B Moderately differentiated
C Poorly differentiated
D Undifferentiated, anaplastic
9 Grade cannot be assessed (GX); Unknown
<BLANK> See Note 1