{
  "abstract": "Significance: Most melanoma deaths arise from metastatic spread, yet current staging imperfectly identifies which primary tumors will progress. Melanin structure is altered during malignant transformation, and pump-probe microscopy (PPM) measures melanin excited-state dynamics in standard biopsy sections, offering molecular contrast that is complementary to morphology-based assessment. Aim: To determine whether PPM-derived melanin excited-state dynamics in primary cutaneous melanoma can predict metastatic outcome. Approach: We imaged unstained sections from 71 primary cutaneous melanomas and 18 melanoma metastases. Transient absorption curves were fit to a biexponential excited-state model, and the fit parameters were used as features for learning classifiers to predict metastatic outcome. Results: Melanin dynamics separated primary from metastatic tissue: both excited-state lifetimes were shorter in primaries, with common-language effect sizes up to 0.26. The same parameters did not separate primary tumors by outcome (effect sizes 0.41-0.61), and univariate logistic regression found no significant association for either the excited-state lifetimes or the ESA/GSB ratio. The best classifier reached 74% patient-level accuracy (AUC 0.73), a plateau reached by several unrelated architectures. Conclusions: PPM robustly distinguishes primary from metastatic melanoma tissue, consistent with progressive melanin disaggregation. While it is clear that pump-probe features of melanin thus correlate with tissue differences, melanin dynamics in single sections of the primary tumor, confounded by heterogeneity, do not give robust predictions of metastatic outcome.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.08814",
  "author_total": 6,
  "authors": [
    {
      "name": "David Grass"
    },
    {
      "name": "Emma Bao"
    },
    {
      "name": "Martin C. Fischer"
    },
    {
      "name": "M. Angelica Selim"
    },
    {
      "name": "Georgia M. Beasley"
    },
    {
      "name": "Warren S. Warren"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/6fdyactcrk516.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.08814",
  "fulltext_url": null,
  "id": "6fdyactcrk516",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.08814",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "physics.med-ph"
    ],
    [
      "arxiv",
      "physics.optics"
    ],
    [
      "openalex",
      "2730|Cutaneous Melanoma Detection and Management"
    ]
  ],
  "openalex": "W7212064914",
  "pdf_url": "https://arxiv.org/pdf/2609.08814",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-08",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/6fdyactcrk516.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:19:52Z",
      "native_id": "2609.08814",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.08814"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:physics.med-ph",
      "subfield": "biological-medical"
    },
    {
      "field": "physics",
      "origin": "arxiv:physics.optics",
      "subfield": "optics-photonics"
    }
  ],
  "title": "Evaluating the predictive power of pump-probe imaging contrast of melanin for metastatic outcome: A 71-patient study",
  "title_text": "Evaluating the predictive power of pump-probe imaging contrast of melanin for metastatic outcome: A 71-patient study",
  "type": "preprint",
  "updated_at": "2026-10-30T12:19:52Z",
  "url": "https://research.draconitic.com/paper/6fdyactcrk516",
  "venue": "arXiv",
  "versions": []
}