Evidence map›Paper›PMID 41639639›Full record

ArticleBMC medical imaging2026

Differentiating lymph node status in malignant melanoma: the role of apparent diffusion coefficient ratio in diffusion-weighted MRI - a prospective diagnostic study.

Marc Philip Elias Kohnen, Matthias Mühler, Andreas Arnold, Stine Lutze, Chia-Jung Busch, Silvia Ribback, Kristin Peters, Marie-Luise Kromrey, Michael Kirsch, Julie Gamain and 2 more

Abstract read
In one paragraph

Article in BMC medical imaging, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

12 authors.

Marc Philip Elias KohnenInstitute for Diagnostic Radiology and Neuroradiology, University Medicine Greifswald, Ferdinand-Sauerbruch-Straße 1, 17475, Greifswald, Germany. mk152071@uni-greifswald.de.
Matthias MühlerInstitute for Diagnostic Radiology and Neuroradiology, University Medicine Greifswald, Ferdinand-Sauerbruch-Straße 1, 17475, Greifswald, Germany.
Andreas ArnoldClinic and Polyclinic for Skin and Venereal Diseases, University Medicine Greifswald, Ferdinand-Sauerbruch-Straße 1, 17475, Greifswald, Germany.
Stine LutzeClinic and Polyclinic for Skin and Venereal Diseases, University Medicine Greifswald, Ferdinand-Sauerbruch-Straße 1, 17475, Greifswald, Germany.
Chia-Jung BuschDepartment of Otorhinolaryngology and Head and Neck Surgery, University Medicine Greifswald, Ferdinand-Sauerbruch-Straße 1, 17475, Greifswald, Germany.
Silvia RibbackInstitute of Pathology, University Medicine Greifswald, Friedrich-Loeffler-Str. 23e, 17487, Greifswald, Germany.
Kristin PetersInstitute of Pathology, University Medicine Greifswald, Friedrich-Loeffler-Str. 23e, 17487, Greifswald, Germany.
Marie-Luise KromreyInstitute for Diagnostic Radiology and Neuroradiology, University Medicine Greifswald, Ferdinand-Sauerbruch-Straße 1, 17475, Greifswald, Germany.
Michael KirschInstitute for Diagnostic Radiology and Neuroradiology, University Medicine Greifswald, Ferdinand-Sauerbruch-Straße 1, 17475, Greifswald, Germany.
Julie GamainInstitute for Diagnostic Radiology and Neuroradiology, University Medicine Greifswald, Ferdinand-Sauerbruch-Straße 1, 17475, Greifswald, Germany.
Fiona Mankertz *Institute for Diagnostic Radiology and Neuroradiology, University Medicine Greifswald, Ferdinand-Sauerbruch-Straße 1, 17475, Greifswald, Germany.
Carolin Malsch *Institute for Mathematics and Computer Science, University Greifswald, Walther-Rathenau-Str. 47, 17489, Greifswald, Germany.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundThis study aimed to investigate a standardized apparent diffusion coefficient (ADC) ratio cut-off for identifying lymph node (LN) metastasis in malignant melanoma (MM), addressing the challenges of current non-invasive LN status diagnostics and dependences of absolute ADC values.

methodsThis prospective, single-center study evaluated consecutive patients using diffusion-weighted MRI (DWI-MRI). We included 52 patients with early-stage MM who underwent sentinel lymph node (SLN) extraction, and 12 patients with advanced-stage MM and newly confirmed or progressive metastatic lymph nodes (MLNs). ADC values for positive and negative SLNs as well as MLNs were measured. Ratios of the ADC of SLNs or MLNs were calculated relative to benign contralateral LNs (cADC) and adjacent muscle tissue (mADC). ROC analysis identified cut-offs for absolute ADC values and relative ADC ratios. Diagnostic performance gained by regression was validated via machine learning (ML) classifiers, to evaluate robustness.

resultsA total of 64 patients (median age 68.5; IQR 61–77; 46.9% female) were included. Significant differences were observed in all ADC measurements using single-shot-echo-planar-imaging (EPI): median cADC was 0.76 (IQR 0.69–0.93) for metastatic SLNs versus 1.02 (IQR 0.91–1.08) for benign SLNs (p = 0.03), mADC was 0.48 (IQR 0.45–0.53) versus 0.61 (IQR 0.56–0.71, p = 0.001). Optimal cut-offs for cADC and mADC in the SLN group were 0.81 (AUC 0.75; 95%-CI 0.47-1) and 0.49 (AUC 0.9; 95%-CI 0.78-1). These closely matched the optimal cut-offs found in the MLN set: cADC 0.83 (AUC 0.98; 95%-CI 0.96-1) and mADC 0.49 (AUC 0.99; 95%-CI 0.98-1). In both sets, these ratios outperformed morphological criteria, such as short-axis diameter (AUC 0.61; 0.38–0.84 in SLN- and 0.86; 0.8–0.92 in MLN set) and Node-RADS (AUC 0.5; 0.27–0.72 and 0.89; 0.84–0.94). ML models reproduced the diagnostic patterns observed in logistic regression.

conclusionThe introduction of a standardized ADC ratio cut-off in DW-MRI to differentiate benign from metastatic lymph nodes in MM offers a valuable, normalized, non-invasive addition to traditional diagnostics, though the findings require confirmation in larger, multicenter and multi-scanner cohorts.

Indexed as

Diffusion Magnetic Resonance ImagingLymphatic MetastasisLymph NodesMelanomaAgedFemaleHumansMachine LearningMaleMiddle AgedProspective StudiesROC CurveSensitivity and SpecificitySentinel Lymph NodeSentinel Lymph Node BiopsyApparent diffusion coefficient ratioDiffusion-Weighted magnetic resonance imagingLymphatic metastasesMalignant melanomaNode-RADS

Identifiers

PMID41639639
PMCPMC12930938

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.