haem.io

Method and Audit Trail

How the Calculator Works

Deterministic ELN response logic with a visible audit trail

The calculator applies ELN 2022 or ELN 2017 response definitions to the entered marrow findings, assessment date, blood counts, extramedullary disease status, circulating blasts, Auer rods, and MRD annotation. It does not hide the decision: every result shows the values used, the selected criteria, and the alternatives that were rejected.

Open calculator No black box

Audit Trace

The same sequence is used for screen results and PDF reports.

1 Choose guideline

ELN 2022 or ELN 2017 is selected before any thresholds are scored.

2 Resolve marrow source

Aspirate blasts are preferred; trephine IHC is used only as a fallback.

3 Select blood counts

Manual values are used directly; pasted or uploaded values are selected from the configured 7-day window.

4 Build criterion checks

Each category receives pass, fail, or missing for every required criterion.

5 Select response

The highest-priority fully met category is returned; missing data can stop selection.

6 Show reasoning

The final result, key values, notes, and full checklist are shown to the user.

Marrow Source Decision

Aspirate first
Aspirate adequate with blast percentage? Use this when the aspirate is adequate and a post-treatment blast percentage is available.
Yes Use aspirate blasts

The report records aspirate morphology as the marrow source.

No Check trephine IHC

Trephine fallback is allowed only when trephine is adequate and an IHC blast percentage is provided.

Yes Use trephine IHC blasts
No Nonevaluable marrow

Missing Data Policy

Could the missing value change the final response?

Example: PR-range blasts with missing baseline blasts, missing count recovery, or response-assessment disease features marked not stated.

Yes

Return assessment incomplete.

No

Continue scoring. Example: MLFS does not require count recovery.

Response Priority

Highest met category wins

Priority determines the final label only after the checklist for every response category has been built. Lower-priority categories may be met but not selected if a higher-priority response is also met.

ELN 2022

  1. CR Complete remission
  2. CRh CR with partial hematologic recovery
  3. CRi CR with incomplete hematologic recovery
  4. MLFS Morphologic leukemia-free state
  5. PR Partial remission
  6. Other No response, nonevaluable, or incomplete

ELN 2017

  1. CR Complete remission
  2. CRi CR with incomplete hematologic recovery
  3. MLFS Morphologic leukemia-free state
  4. PR Partial remission
  5. Other Treatment failure, nonevaluable, or incomplete

What the User Sees

  • Final response category, guideline version, and MRD annotation if supplied.
  • Key values used: blast source, marrow blasts, ANC, platelets, EMD, circulating blasts, and Auer rods.
  • Assessment date, blood count window, and source dates when pasted/uploaded blood counts are used.
  • Selected-category decision trail and criterion checklist.
  • Compact summaries for all other categories considered.
  • Same reasoning in the downloadable PDF report.

Special Rules Worth Knowing

ELN 2022 does not use Auer rods as a response exclusion. ELN 2017 retains Auer rods in CR, CRi, MLFS, and PR logic. Response-assessment disease features can be present, absent, or not stated. Pasted or uploaded blood counts use the highest eligible ANC and platelets in the selected 7-day window. CRh requires ANC >=0.5 and platelets >=50. CRi is selected after CRh when ELN 2022 CRh is used. MLFS does not require hematologic recovery. PR requires CR blood-count recovery and >=50% marrow blast reduction.

Exact ELN Criteria Implemented

Shown in every result
Category
ELN 2022
ELN 2017
CR
BM blasts <5%; circulating blasts absent at response assessment; EMD absent at response assessment; ANC ≥1.0; platelets ≥100.
BM blasts <5%; circulating blasts and blasts with Auer rods absent at response assessment; EMD absent at response assessment; ANC ≥1.0; platelets ≥100.
CRh
ANC ≥0.5 and platelets ≥50, otherwise all other CR criteria met.
Not an ELN 2017 response category in this implementation.
CRi
All CR criteria except residual neutropenia or thrombocytopenia; selected only when CRh is not met.
All CR criteria except residual neutropenia or thrombocytopenia.
MLFS
BM blasts <5%; circulating blasts absent at response assessment; EMD absent at response assessment; no hematologic recovery required.
BM blasts <5%; blasts with Auer rods absent at response assessment; EMD absent at response assessment; no hematologic recovery required.
PR
Hematologic CR criteria; BM blasts 5-25%; pretreatment BM blasts reduced by ≥50%.
Hematologic CR criteria, including absence of blasts with Auer rods; BM blasts 5-25%; pretreatment BM blasts reduced by ≥50%.

Primary Sources

Table mapped

ELN 2022: Dohner et al. Blood 2022;140(12):1345-1377, Table 8.

ELN 2017: Dohner et al. Blood 2017;129(4):424-447, Table 6.