Refining Histology Coding for GYN Malignancies: Focus on Serous Carcinoma
Accurate histology coding is essential for cancer surveillance, research, and clinical decision-making.
For gynecologic (GYN) malignancies, particularly those involving serous carcinoma, the Solid Tumor Rules (STR) and updated ICD-O standards provide a structured framework to ensure consistency and precision in cancer registry data.
Prioritizing Histology Coding Standards
The Solid Tumor Editors recommend the following hierarchy when coding histology:
1. Solid Tumor Rules (STR)
2. Updated ICD-O histology codes and terms
3. ICD-O-3.2
To support this process, the Cancer PathChart CPC Search Tool offers an interactive platform for validating site, histology, and behavior terms for cases diagnosed from January 1, 2024, onward. This tool is accessible at https://seer.cancer.gov/cancerpathchart/search/tool/.
Coding Serous Carcinoma and Its Synonyms
The STR module for “Other Sites” includes specific guidance for coding histology in GYN malignancies when a diagnosis of serous carcinoma or its synonyms is present. The base code for serous carcinoma NOS is 8441, with the following related codes:
• Serous intraepithelial carcinoma – 8441/2
• Serous tubal intraepithelial carcinoma (STIC) – 8441/2
• Serous endometrial intraepithelial carcinoma – 8441/2
• Serous cystadenocarcinoma NOS – 8441/3
• Serous adenocarcinoma – 8441/3
• Serous papillary adenocarcinoma NOS – 8441/3
• Papillary serous adenocarcinoma – 8441/3
· Serous surface papillary carcinoma 8441/3
Subtypes and Variants: Effective from 2021 Onward
For ovary, fallopian tubes, and peritoneum only (excluding endometrial primaries), the following histology codes are effective for diagnoses made in 2021 and forward:
• High-grade serous carcinoma (HGSC) – 8461/3
• Low-grade serous carcinoma / Micropapillary serous carcinoma – 8460/3
• Serous carcinoma, non-invasive, low grade – 8460/2
• Papillary serous cystadenocarcinoma – 8460
It is important to note that high-grade and low-grade serous carcinoma codes are not valid for endometrial primaries. In such cases, the appropriate code remains 8441/3.
Historical Coding Practices (Pre-2021)
Before 2021, the following histology’s were commonly used for serous carcinomas in GYN sites:
• Adenocarcinoma, papillary, serous – 8460
• Adenocarcinoma, serous, NOS-8441/3
• Adenocarcinoma, serous, papillary – 8460/3
• Carcinoma, papillary, serous surface – 8461/3
• Carcinoma, serous surface papillary – 8461/3
• Carcinoma, serous, NOS – 8441/3
• Cystadenocarcinoma, papillary serous – 8460/3
• Cystadenocarcinoma, serous, NOS (C56.9) – 8441/3
• Papillary adenocarcinoma, serous – 8460/3
• Papillary carcinoma, serous surface – 8461/3
• Papillary cystadenocarcinoma, serous – 8460/3
• Papillary serous adenocarcinoma – 8460/3
• Papillary serous cystadenocarcinoma – 8460/3
• Serous adenocarcinoma, NOS – 8441/3
• Serous adenocarcinoma, papillary – 8460/3
• Serous cystadenocarcinoma, NOS – 8441/3
The ICD-O-3 Annotated Histology List, maintained by the CDC’s NPCR Registry Plus team, provides a downloadable Excel file that includes:
• ICD-O-3 histology codes
• Behavior codes
• Preferred and non-preferred terms
• Synonyms and related terms
Each histology-behavior combination is flagged with a “Preferred Term” indicator to guide consistent reporting. This resource is available at https://www.naaccr.org/icdo3/..
As cancer coding evolves, staying current with histology classifications and coding rules is essential for accurate data collection and reporting. By following the Solid Tumor Rules, utilizing updated ICD-O codes, and leveraging tools like the Cancer PathChart, registrars and researchers can ensure high-quality, standardized data that supports cancer surveillance and patient care.
Adenocarcinoma, serous - 8441/3
Click on the tags below to see related articles: