Problem Statements
We started working on TU/TR domains when this question was raised: if an abnormality can be considered as a lesion, should it be modeled in the TU/TR structure? This question came from modeling aneurysm data from the cardiovascular TA projects, where the aneurysm data were originally mapped to the CV domain and discussions had taken place on whether it should be mapped to TU/TR. We then noticed modeling inconsistencies between tumor vs non-tumor lesion findings data: Tumors are neoplastic lesions while an aneurysm can be considered as a non-neoplastic, cardiovascular lesion. They all are considered as lesions, why is the modeling for the two types of lesions so different and inconsistent in TU?
TU/TR/RS were originally created for tumor identification and (tumor) disease assessment data. Non-tumor lesion modeling was later added onto TU/TR. RS was also combined with CC in either 2018 or 2019.
Arguments have been made that Tumor finding data modeling is prefaced on “already identified tumors”. TU records are created for each “identified tumor”, with the creation of a unique tumor ID (TULNKID). Since only already identified tumors are mapped to TU, this means, the locations (produced by imaging procedures) where one looked for the presence of a tumor and didn’t find it, is NOT modeled in TU.
- This is in part due to the fact that imaging location is treated as a procedure attribute and is mapped to procedure.
The results for TUTEST = Tumor Identification, are typically TUORRES = Target and Non-target. However results for this test can also be: BONE LESION, measurable/non-measurable, benign/malignant, new, etc. We think the purpose of this test is to identify the “role” of a tumor, such as tumor type, malignancy status, measurability, etc. However, TU domain definition also states that TU is used to identify the location of the tumor. There is no specific TUTEST associated with the tumor location identification process - tumor locations are treated as a known fact and are mapped to TULOC directly for the Tumor Identification TUTEST. It isn't clear whether TUTEST = Tumor Identification, is also intended to be used to identify the location of the tumor.
Identified tumors are considered to be target/non-target according to published criterion (e.g. RECIST) and this is to classify tumors for the subsequent assessment of disease response to treatment (RS).
This doesn’t work for non-tumor lesions, because:
- There is a need to model whether or not a non-tumor lesion is identified in a region.
- This requires imaging location to be modeled in the TU domain.
- TU modeling needs to allow the creation of a “negative” record – I looked at this location but didn’t find what I suspected.
- Lesion "Type" and "Location" identifications are a separate process and test from "Role" identification. During the location identification process, the location for an identified lesion is a result qualifier. When this lesion undergoes "role" assessment, the location of the identified lesion is then a test qualifier.
- Once the location for a non-tumor lesion is identified, this lesion may not be assigned a role (i.e. target) because said lesion will not undergo “assessment of disease response to therapy (i.e. RS)”. This lesion may be further classified based on severity, anatomy or other types of classifications according to a published, validated public domain or copyrighted criteria. In this case, this should be modeled in the CC portion of the RS/CC combined domain.
The concept map below describes the modeling discrepancies between tumor and non-tumor lesions. Note the dotted lines and boxes indicate a step that didn't happen and data not modeled.
Agreed Approaches so Far
- Imaging location should be treated as the TEST Location when identifying the location of a suspected object.
- We will not make changes to the tumor findings modeling in TU, several cancer TAUGs have been published and we do not want to cause backward compatibility issues. We will only update the non-tumor lesions side.
Domain Level Questions
- If all I need to do is to identify the type of a lesion, it’s location, characterize its physical properties (e.g. diameter measurement) and then evaluate its severity, there is no disease response to treatment data, in other words I have TU, maybe TR and CC data, but no RS, can I use the TU/TR structure?
- How do we model Result Location, when the result itself is the location? Should this be modeled in variables (RESLOC), or should we create tests for result location findings?
- Lesion "Type" and "Location" identification should be modeled separately from "Role" Identification.
- Just because something can be considered as a lesion, should it be modeled in TU/TR?
Recommendations
- Combining domains cause modeling inconsistencies. Oftentimes domains are created by different groups under different circumstances. The premises based on which a domain is built varies greatly for essentially, the same type of data (Tumor vs Non-tumor lesions). Because domains are governed by different teams (i.e. oncology and QRS SDS/CT teams), there are also different CT business rules developed for different domains.
- May consider adding an assumption to better define "lesion" for TU: A localized pathological or traumatic structural change, damage, deformity, or discontinuity of tissue, organ, or body part (C3824). Anything that causes fundamental architectural changes to the structure is considered as a lesion. Jordan Li : ask Al and Nick to draft a better definition for lesion.
- Consider updating the TUTEST = Tumor Identification to: Tumor "Role" Identification