Lithuanian Breast Diagnostics Implementation Guide
0.0.1 - ci-build
Lithuanian Breast Diagnostics Implementation Guide, published by Lithuanian Medical Library. This guide is not an authorized publication; it is the continuous build for version 0.0.1 built by the FHIR (HL7® FHIR® Standard) CI Build. This version is based on the current content of https://github.com/HL7LT/ig-lt-breast/ and changes regularly. See the Directory of published versions
The breast cancer screening and diagnostic workflow is a structured, sequential clinical process that supports the early detection, diagnosis, and classification of breast cancer. The workflow is driven primarily by diagnostic imaging and subsequent clinical decision-making across multiple clinical specialties, including radiology, pathology, and oncology.
The workflow begins with an imaging acquisition visit, during which the patient is physically present and one or more imaging procedures are performed, typically including mammography and, when indicated, tomosynthesis or ultrasound.
The process starts when a clinician or screening programme initiates a breast imaging examination by placing an imaging order, for example a breast screening request. The order specifies the type of examination (screening or diagnostic), the anatomical focus, and any relevant clinical indications.
During the imaging acquisition visit, a radiology technologist performs the imaging procedures, such as mammography (example: Mammography Procedure), tomosynthesis, or breast ultrasound. The patient is present during this encounter (example: Breast Imaging Acquisition Encounter).
The resulting imaging data are captured as structured ImagingStudy resources together with contextual information such as breast laterality, quadrant localisation, breast density, and relevant clinical background. No diagnostic conclusion is made at this stage.
After acquisition, the imaging studies are interpreted by a radiologist, usually in a separate evaluation encounter without the patient present.
The radiologist reviews the imaging data and documents findings such as masses, calcifications, asymmetries, or architectural distortions as structured observations, for example:
The radiologist then assigns a BI-RADS category using a BI-RADS Assessment (example: BI-RADS 4) and compiles the results into a structured imaging diagnostic report.
The diagnostic report includes:
Digital breast tomosynthesis (DBT) is used as a supplementary imaging modality when mammographic findings are inconclusive (typically BI-RADS 0). The indication for tomosynthesis is usually a prior mammographic assessment requiring additional imaging.
Tomosynthesis findings are recorded using the Tomosynthesis Examination Finding profile, which captures:
The radiologist assigns a BI-RADS category and recommendation using the same assessment and referral profiles as mammography.
Tomosynthesis findings are included in the Breast Composition alongside mammographic and ultrasound findings.
A central design principle of the workflow is the explicit separation between:
The BI-RADS category acts as the main decision point:
The recommended action is represented as a ServiceRequest, for example a BI-RADS 4 referral.
If additional imaging is recommended, a new imaging order is created and the patient undergoes further imaging studies, generating new imaging datasets and reports.
If biopsy is indicated (typically BI-RADS 4–5), an image-guided biopsy procedure is performed. The procedure is documented using the Breast Biopsy Procedure profile, which captures:
Multiple changes may be biopsied in a single session. Each biopsied change generates a separate specimen container, with information about localization (by clock position for ultrasound-guided procedures, or by quadrant for X-ray-guided procedures) and the size of the biopsied entity in millimeters.
If lymph node biopsy is performed, the localization (right/left), involvement level (N1/N2/N3), and size of the lymph node are recorded.
Detailed biopsy data is also captured via the Biopsy ESPBI Questionnaire which includes additional fields for sample containers, radiological conclusion, and facility information.
The collected tissue specimens are transported to the pathology laboratory and analysed as part of a structured diagnostic reporting process defined in the Lithuanian Laboratory IG.
The pathology report follows the Pathology Composition structure from the Laboratory IG, organized into four LOINC-coded sections:
The microscopic section includes structured observations for immunohistochemical tests:
When HER2 IHC results are borderline (2+), molecular testing is performed:
Histological grading uses the Histological Grading value set (G1–G3, Gx). Lymphovascular invasion is assessed using the pLVI Classification (pLVI-0 to pLVI-4, pLVI-9).
The final diagnosis uses the WHO Breast Tumor Classification value set, which includes approximately 80 tumour types from the WHO Classification of Tumours, 5th edition. Each diagnosis is coded with SNOMED CT and accompanied by ICD-10-AM and ICD-O-3 morphology codes in the Pathology Report.
Detailed pathology data is also captured via the Pathology ESPBI Questionnaire.
The pathology diagnostic report is reviewed and signed off by the pathologist and communicated back to the referring clinician. At this point, the diagnostic phase of the workflow is complete and the patient may be referred onward for treatment planning, oncology consultation, or follow-up, depending on the diagnosis.
This workflow model reflects real clinical practice while ensuring a clear separation between:
It provides a structured and interoperable representation of the breast cancer screening and diagnostic pathway and supports standardised data exchange, reporting, and programme monitoring within the national breast cancer screening and diagnostic programme.