Update to current manual/Solid Tumor Rules (2018)/Histology--Lung: What is the histology code and what M Rule applies when there are multiple specific subtypes identified using various equivalent lung terms but only one is stated to be predominant? See Discussion.
Example: Lung resection final diagnosis is Lung adenocarcinoma, see Summary Cancer Data, and the Summary Cancer Data (CAP Synoptic Report) states Histologic type: Invasive adenocarcinoma, solid predominant. Other Subtypes Present: 20% acinar and <5% micropapillary components.
Instruction 1B and Note 1 for Coding Multiple Histologies (Lung Histology Rules) indicates type, subtype, component, and predominantly are all terms that may be used to code the most specific histology. In this case, the multiple specific histologies were documented using all of those terms.
Note 2 for instruction 1B states predominantly describes the greatest amount of tumor and when it is used for the listed subtypes of adenocarcinoma, that subtype should be coded. However, Note 2 does not indicate that the other subtypes are ignored when one is identified to be predominant and the others are identified as subtype or component only.
Code to invasive adenocarcinoma, solid predominant (8230/3), based on the example, using Lung Solid Tumor Rules Coding Multiple Histologies instruction #1 that says to code the specific histology where the most specific histology may be described as component, majority/majority of, or predominantly, in this case, 75%. Apply Rule M2 as this appears to be a single tumor with multiple histologies based on the information provided.
The rules will be updated to add a new H rule and to reviseTable 2 when two or more histologies described as predominant are present.
MP/H Rules/Histology--Breast: What histology code and MP/H Rule applies to the Histologic Type of "invasive ductal carcinoma with metaplastic stroma" for a single breast tumor? See Discussion.
The patient had a partial mastectomy with final diagnosis of invasive ductal carcinoma with metaplastic stroma. Knowing that metaplastic breast carcinoma has a worse prognosis than other types of breast cancer, is metaplastic stroma a synonym for metaplastic carcinoma when used in this context?
Code to metaplastic carcinoma, 8575/3. According to our expert pathologist consultant, "The term 'metaplastic stroma' implies that at least a portion of the carcinoma has undergone a 'metaplastic' change from epithelial in appearance to 'stromal' in appearance. I assume this is what CAP means by 'Invasive mammary carcinoma with matrix production,' which the WHO equates to metaplastic carcinoma."
Histology (Pre-2007)--Breast: What code is used to represent the histology "Ductal carcinoma in situ; 6 mm focus of invasion is a pure mucinous carcinoma that appears to have arisen in the background of encysted papillary carcinoma."
Code to mucinous (8480) since that is the only clearly invasive component of this diagnosis.
According to our pathologist consultant, "Encysted papillary carcinoma is the same thing as intracystic papillry carcinoma, which I think of as an intraductal papillary carcinoma which has greatly expanded the duct to form a cyst-like structure. It generally behaves in an in-situ rather than an invasive fashion. The only clearly invasive component is the mucinous carcinoma, which is what I would code."
Solid Tumor Rules/Histology--Thyroid: What is the correct histology code for a papillary carcinoma, encapsulated with columnar cell features? See Discussion.
There is an ICD-O histology code for papillary carcinoma, columnar cell (8344/3) as well as papillary carcinoma, encapsulated (8343/3). Per Rule H13, the terms “with features of” may be used to identify a subtype.
Considering these two subtypes, and knowing there is no specific histology code for this combination, is the first rule that applies H17 (code the numerically higher histology code)?
Code to papillary carcinoma, encapsulated (C73.9) (8343/3) using Solid Tumor Rules, Other Sites, Rule H11, code the histology when only one histologic type is identified. The usage of features is describing the cellular architecture of the encapsulated papillary carcinoma and does not necessarily indicate a specific histologic type. We consulted with our endocrine specialist pathologist who agrees and indicated terminology used in thryoid neoplasms is inconsistent.
Primary Site--Heme & Lymphoid Neoplasms: What primary site code should be assigned and what rule justifies that code?
Scenario: Pleural effusion, underwent thoracentesis. Pleural fluid unexpectedly showed Large B-Cell Lymphoma. Extensive workup including CT & PET was done and all findings were within normal limits. No evidence of lymphoma was seen and no palpable adenopathy was found. The only indication of lymphoma was the malignant pleural effusion.
Code to pleura, C384.
Per the Hematopoietic database, Diffuse Large B-Cell Lymphoma can originate in the pleural cavity.
Solid Tumor Rules/Histology--Thyroid: What is the histology code for a diagnosis of poorly differentiated thyroid carcinoma arising in a background of solid papillary thyroid carcinoma? See Discussion.
Patient had a hemithyroidectomy with the final diagnosis above. There does not appear to be an Other Sites H rule or table that addresses this combination of histologies for thyroid primaries.
Code to poorly differentiated thyroid carcinoma, 8337/3.
In this case the tumor is comrpised of two difffernat thyroid histologies: poorly differentiated carcinoma 8337/3 and papillary thyroid carcinoma 8260/3. WHO does not have a code for this combination. Per our endocrine pathology expert, the poorly differentiated carcinoma is the more agressive histology and will determine treatment and progrnosis.
Other Therapy: How do we classify "thalidomide" when it is given as cancer directed therapy?
Code to the appropriate code (1, 2 or 3) under Other Therapy, depending on whether the drug was given as part of a clinical trial. If not part of a clinical trial, assign code 1 [Other cancer-directed therapy].
Thalidomide is not FDA approved for treating cancer. It is under investigation for anti-angiogenesis effects in different cancers.
Radiation Therapy: Would tomotherapy, described as targeted IMRT, be coded as external beam?
Code tomotherapy as 1 [Beam radiation].
Tomotherapy is external beam radiation therapy. It is a type of IMRT. Intensity-modulated radiation therapy (IMRT) is an advanced mode of high-precision radiotherapy that utilizes computer-controlled x-ray accelerators to deliver radiation. Tomotherapy is a CT image guided IMRT.
Chemotherapy: How is treatment with Iressa (Gefitinib) coded?
Code treatment with Iressa as chemotherapy.
Iressa is an epidermal growth factor inhibitor. While it doesn't kill cells directly, it damages the cell reproduction process. We classify it as a chemotherapy agent.
Primary Site--Bladder: Does instruction #4 in the Urinary Sites Solid Tumor Rules Instructions for Coding Primary Site apply to a mix of in situ and invasive urothelial tumors?
Instruction #4: Code Urinary System NOS C689 when there are multiple non-contiguous tumors in multiple organs within the urinary system.
See Discussion.
Example: Patient has multiple biopsies with final diagnosis of in situ papillary urothelial carcinoma in the prostatic urethra and invasive papillary urothelial carcinoma in the bladder.
How should primary site be coded in this type of mixed in situ and invasive situation?
Code Urinary System NOS C689 for this case since there are two separate urinary sites involved. Apply instruction #4 when there is a mix of in situ and invasive urothelial tumors.