# Quest Diagnostics

Source: https://onco.cc/companies/quest-diagnostics/  
OnCo record `quest-diagnostics` (Company). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

Quest Diagnostics is a national reference laboratory with oncology pathology and molecular testing, including Haystack Oncology MRD (acquired 2023).

## Summary

Quest Diagnostics, based in Secaucus, New Jersey, and listed as DGX, is a national reference laboratory with oncology pathology and molecular testing, including the Haystack Oncology measurable residual disease test acquired in 2023. Its oncology work spans AmeriPath anatomic pathology, solid-tumour next-generation sequencing and circulating tumour DNA MRD testing through Haystack. OnCo links it to reference laboratories and companion diagnostic testing, MRD testing and Haystack Oncology. Whether a general reference laboratory can compete in MRD testing against specialist companies is the question the Haystack purchase poses. Haystack Oncology has its own page.

## Fields

- Kind: Company
- Last checked: 2026-09-08
- Tags: supporting
- HQ: Secaucus, NJ
- Type: diagnostics
- Website: https://www.questdiagnostics.com
- Ticker: DGX

## Sources

- Official website: https://www.questdiagnostics.com

## Connected records

- fronts: [Diagnostics & Biomarkers](https://onco.cc/fronts/diagnostics/)
- technologies: [MRD / molecular residual disease testing](https://onco.cc/technologies/mrd-testing/), [Reference laboratories and companion-diagnostic testing](https://onco.cc/technologies/reference-laboratories/)
- companies: [Haystack Oncology](https://onco.cc/companies/haystack-oncology/)

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JSON: https://onco.cc/api/v1/entities/quest-diagnostics.json