How to visualize lines of therapy charts
Filip Barl
| June 17, 2026
June 17, 2026
Lines of therapy data can be difficult to communicate clearly.
You may have a table showing first-line, second-line, and third-line treatments, along with how many patients continue, switch or discontinue treatment at each step. But in spreadsheet form, the main pathways are not always obvious.
A Sankey diagram is one practical way to make that pattern easier to see.
Instead of reading treatment transitions row by row, you can quickly identify the main therapy pathways, the largest branches, and where the flow becomes more fragmented over time.
This makes Sankey diagrams useful for lines of therapy charts, treatment pathway visualizations and other healthcare flow charts, because they show both sequence and volume in one view.
What data you need
In simple terms, a lines of therapy Sankey diagram only needs three columns: From, To and Amount.
Each row represents one transition from one therapy to the next, along with the number of patients following that path. To make the data work correctly, the treatment name should always include the treatment stage, such as OXC (1L), OXC (2L), and OXC (3L).
This keeps the stages distinct in the chart, even when the same therapy appears in multiple lines of treatment.
Here is our example to get you started:
| From | To | Amount |
|---|---|---|
| OXC (1L) | OXC (2L) | 4 |
| LEV (1L) | OXC (2L) | 7 |
| LEV (1L) | BRV (2L) | 1 |
| LEV (1L) | LEV (2L) | 4 |
| LEV (1L) | VPA (2L) | 6 |
| LEV (1L) | STM (2L) | 2 |
| LEV (1L) | PB (2L) | 2 |
| LEV (1L) | CBZ (2L) | 1 |
| VPA (1L) | LEV (2L) | 1 |
| VPA (1L) | VPA (2L) | 4 |
| VPA (1L) | CBZ (2L) | 1 |
| PB (1L) | LEV (2L) | 1 |
| PB (1L) | PB (2L) | 7 |
| PB (1L) | STM (2L) | 1 |
| STM (1L) | STM (2L) | 1 |
| STM (1L) | CBZ (2L) | 1 |
| CBZ (1L) | CBZ (2L) | 4 |
| AZA (1L) | AZA (2L) | 2 |
| OXC (2L) | OXC (3L) | 11 |
| BRV (2L) | OXC (3L) | 1 |
| LEV (2L) | OXC (3L) | 1 |
| LEV (2L) | LEV (3L) | 5 |
| VPA (2L) | OXC (3L) | 2 |
| VPA (2L) | VPA (3L) | 7 |
| VPA (2L) | VGB (3L) | 1 |
| STM (2L) | STM (3L) | 4 |
| PB (2L) | PB (3L) | 9 |
| CBZ (2L) | OXC (3L) | 1 |
| CBZ (2L) | CBZ (3L) | 6 |
| AZA (2L) | AZA (3L) | 2 |
Start with this template
Use our Lines of Therapy template as a starting point, then replace the example data with your own treatment flows.
Open templateWhat the finished chart can look like
Once the data is entered, SankeyArt automatically turns it into a readable Sankey diagram. From there, a few small adjustments can improve readability further:
- Apply colors to all chart nodes, keeping therapy colors consistent so recurring therapies remain easy to recognize across stages
- Adjust the layout manually where needed by dragging nodes to make the main treatment patterns easier to see
Here is an example of the finished chart:
Beyond lines of therapy
The same approach also works well for other healthcare flow charts, including:
- patient journey diagrams
- referral pathways
- treatment switching patterns
- care pathway maps
- discharge pathways
Any time you need to show how patients, treatments or cases move through a sequence, a Sankey diagram can be a useful format.
Have a healthcare use case you would like to visualize? Write to use at support@sankeyart.com.

Filip Barl
Filip is a software engineer and the technical mind behind SankeyArt.
He’s passionate about building great software and tackling complex technical challenges. With a strong interest in design and UX, he strives to create seamless and intuitive experiences.