KRAS/NRAS Testing: Nursing Guide
KRAS and NRAS are genes in the MAPK pathway downstream of EGFR. Somatic mutations in tumor tissue predict lack of benefit from anti-EGFR monoclonal antibodies (cetuximab or panitumumab) in metastatic colorectal cancer. Nurses protect patients by confirming extended RAS testing before anti-EGFR orders, ensuring adequate tumor for pathology, avoiding confusion with germline cancer-risk testing, and escalating acute oncology symptoms regardless of pending biomarker results.
Contents
Quick Facts
Key Takeaway
Extended KRAS/NRAS testing on tumor tissue guides anti-EGFR eligibility — a detected RAS mutation means cetuximab or panitumumab should not be used for benefit in standard mCRC pathways, not that the nurse.
Gene & Method Details
Nurse quick-reference for specimen routing, consent context, and result handoff.
KRAS exons 2, 3, and 4; NRAS exons 2, 3, and 4 (extended RAS panel per ASCO/NCCN)
DNA sequencing or PCR-based genotyping on tumor tissue — platform varies by CLIA-certified molecular pathology laboratory; next-generation sequencing panels may include additional actionable alterations when ordered
Formalin-fixed paraffin-embedded (FFPE) tumor block or unstained slides from primary colon/rectal tumor or metastasis with adequate malignant cell content
Somatic (tumor-acquired; not inherited HBOC testing)
Commonly days to several weeks depending on laboratory — not specified as a single universal turnaround in the published references
Somatic (tumor-acquired) mutation testing for treatment selection — distinct from germline hereditary cancer predisposition testing
Oncology-led treatment discussion is required; this is not germline HBOC counseling. Document informed consent for biopsy/tissue testing per institutional oncology policy.
What is KRAS/NRAS Testing?
KRAS/NRAS Testing detects somatic mutations in KRAS and NRAS in tumor tissue. In metastatic colorectal cancer, extended RAS testing (exons 2, 3, and 4 of both genes) identifies patients who should not receive anti-EGFR monoclonal antibody therapy because MAPK pathway mutations essentially preclude cetuximab or panitumumab benefit. Results inform systemic therapy planning with oncology — they do not diagnose cancer by themselves.
Overview
Nurses encounter KRAS/NRAS testing on oncology units and infusion clinics when patients have metastatic colon cancer or selected lung cancer pathways where anti-EGFR therapy is considered. NCCN and ASCO recommend extended RAS genotyping on tumor tissue in all patients with metastatic colorectal cancer so anti-EGFR decisions are planned before exposure to ineffective, toxic, and costly therapy.
ASCO’s provisional clinical opinion specifies testing in a CLIA-certified laboratory for KRAS and NRAS codons 12 and 13 (exon 2), 59 and 61 (exon 3), and 117 and 146 (exon 4). Testing only KRAS exon 2 misses mutations that still predict anti-EGFR resistance. NIH Medical Genetics Summaries note that any known KRAS or NRAS mutation generally precludes cetuximab or panitumumab unless a guideline-defined exception applies.
Before anti-EGFR administration, verify extended RAS results are documented on the tumor specimen used for treatment decisions. If results are pending, clarify with oncology and pharmacy per protocol — do not assume wild-type status. Teach patients that biomarker results guide drug selection, not daily symptoms alone. Escalate blood in stool, bowel obstruction signs, or acute pain according to facility policy while molecular results are pending.
Anti-EGFR Therapy and RAS Result Safety
Extended RAS results directly affect anti-EGFR eligibility. Giving cetuximab or panitumumab when a KRAS or NRAS mutation is already documented exposes the patient to toxicity without expected benefit. Nurses prevent harm by MAR verification, prescriber and pharmacy notification, and clear somatic-versus-germline teaching.
- Anti-EGFR biologic scheduled while extended RAS panel shows KRAS or NRAS mutation
- Only KRAS exon 2 tested when full extended RAS panel is required before anti-EGFR
- QNS or failed assay with anti-EGFR infusion imminently and no oncology clarification
- Acute bowel obstruction or sepsis deferred because molecular results are pending
Document: specimen block ID, extended RAS classification, anti-EGFR hold actions, prescriber/pharmacy notification, patient teaching, and acute symptom escalation.
What KRAS/NRAS Tumor Testing Can and Cannot Tell You
This test can help identify:
- Somatic KRAS and NRAS mutations in assayed exons on tumor tissue from primary or metastatic sites
- Patients who should not receive standard anti-EGFR monoclonal antibody therapy when mutations are detected
- RAS wild-type status when extended panel is complete — prerequisite for oncology to consider anti-EGFR with other criteria
- Biomarker context alongside BRAF, MSI/MMR, and sidedness in comprehensive mCRC planning
This test cannot:
- Diagnose colorectal cancer by itself — pathology and staging still define malignancy
- Replace oncology regimen selection or independent nursing changes to chemotherapy
- Rule out all MAPK pathway alterations if only partial RAS panels are performed
- Identify inherited cancer predisposition — that requires separate germline testing and counseling
Somatic RAS Results vs Germline Testing
KRAS/NRAS testing for anti-EGFR decisions analyzes somatic mutations in tumor cells — not inherited HBOC-style germline panels. Patients often confuse the two. Nurses use oncology-approved language: a RAS mutation in the tumor guides which medicines may work; it is not automatically a message for relatives to pursue cascade germline testing unless a separate hereditary panel is ordered.
- Document tissue testing consent per institutional oncology policy — not generic germline counseling scripts
- Route complex inheritance questions to genetics or oncology — do not promise family testing from somatic RAS alone
- When QNS or assay failure occurs, explain that valid RAS status is needed before anti-EGFR exposure per protocol
Pre-analytic Checks Before Extended RAS Testing
Verify
Clarify before proceeding when:
- Order requests partial KRAS exon 2 only but anti-EGFR therapy is planned
- Wrong block year or site compared with current treating metastasis
- Anti-EGFR on MAR while documented RAS mutation remains unaddressed
- QNS specimen with biologic infusion scheduled within 24 hours
- Patient confuses somatic RAS with germline family testing needs
- Duplicate extended RAS testing recently completed without clinical indication
- Team plans to defer acute abdominal evaluation until molecular results return
Wild-Type, Mutant, and Pending RAS Results in Treatment Planning
Integrate extended RAS status with MAR, infusion schedule, BRAF/MSI results, tumor sidedness, and symptoms. Mutation detected generally precludes standard anti-EGFR use; wild-type extended RAS permits oncology consideration when other criteria are met; QNS requires repeat tissue or alternate assay per pathology.
| Clinical context | Pair with RAS result | Nursing focus |
|---|---|---|
| KRAS or NRAS mutation, anti-EGFR on MAR | RAS mutant | Hold biologic per protocol; notify prescriber and pharmacy; document teaching |
| Extended RAS wild-type, signed anti-EGFR after pharmacy check | RAS wild-type | Proceed only per verified orders; monitor infusion reactions |
| QNS or assay failure | Indeterminate | Do not assume wild-type; notify oncology and pathology |
| Acute abdomen during pending biomarkers | Any RAS status | Escalate per protocol — do not wait for molecular report |
On a small screen, swipe or scroll sideways to see the full table.
Tissue Validity and Anti-EGFR Hold Conversations at the Bedside
| Bedside point | Nursing note |
|---|---|
| MAR vs mutation | Never administer anti-EGFR when chart shows KRAS/NRAS mutation unless oncology exception documented |
| Extended panel | Exon 2-only results are insufficient for anti-EGFR decisions per ASCO extended RAS guidance |
| Block tracking | Verify pathology accession matches patient identifiers before calling result wild-type |
| Somatic language | Avoid telling families to test children based on tumor RAS alone |
| Pending results | Clarify hold rules with pharmacy — do not assume benefit while RAS is QNS |
| Symptoms first | Obstruction, bleeding, and sepsis trump biomarker timelines |
On a small screen, swipe or scroll sideways to see the full table.
The clarify / hold rule
Clarify before proceeding when:
- Extended RAS panel incomplete but anti-EGFR infusion is scheduled
- Documented RAS mutation conflicts with active cetuximab or panitumumab order
- Specimen QNS or wrong block site for current treating metastasis
- Patient cannot explain basic purpose of tumor gene testing at teach-back
- Duplicate testing ordered without oncology indication
- Acute red-flag symptoms are deferred until molecular results return
- Germline counseling ordered but somatic RAS panel was the clinical question
KRAS/NRAS Testing in Metastatic CRC Treatment Pathways
Diagnostic safety badge: Critical-result test — prompt review and escalation may be required when RAS status affects imminent anti-EGFR therapy.
Check-before-test protocol
- Verify extended KRAS/NRAS order and tumor block ID
- Confirm pathology release to CLIA molecular laboratory
- Review MAR for anti-EGFR biologics against pending or resulted RAS status
- Align infusion dates with expected molecular turnaround per policy
- Teach-back on biomarker-guided therapy and reportable symptoms
Critical teach-back questions
- “Can you tell me why KRAS/NRAS testing is being done on your tumor sample?”
- “What should you report right away while waiting for or after results?”
- “Who will explain how your results change your treatment plan?”
Care coordination: medical oncology, pathology, molecular laboratory, infusion pharmacy, clinical trials team when applicable, and rapid response per institutional protocol for acute complications.
Extended RAS Testing Quick Safety Checklist
- Is extended RAS status documented before anti-EGFR administration?
- Does the block ID match the treating metastasis on the chart?
- Did I hold and notify when mutation conflicts with the MAR?
- Are acute abdominal or sepsis symptoms escalated regardless of pending biomarkers?
- Did I document prescriber/pharmacy notification and patient teaching?
Why KRAS/NRAS Testing is Ordered
Extended KRAS/NRAS testing is ordered when tumor RAS status is needed to plan systemic therapy — especially before or during consideration of anti-EGFR monoclonal antibodies in metastatic colorectal cancer.
| Clinical Indication | What the Test Answers | Nursing Rationale |
|---|---|---|
| Newly diagnosed or recurrent metastatic colorectal cancer | Will anti-EGFR therapy be considered in the treatment continuum? | NCCN strongly recommends RAS (KRAS/NRAS) genotyping on tumor tissue in all mCRC patients so anti-EGFR eligibility is established early in the care pathway. |
| Planning cetuximab or panitumumab-containing regimens | Is extended RAS wild-type status confirmed on the treating specimen? | ASCO states anti-EGFR monoclonal antibody therapy should only be considered when no KRAS or NRAS mutations are detected after extended RAS analysis in a CLIA-certified lab. |
| Tumor tissue available from primary resection or metastatic biopsy | Is there adequate malignant tissue for molecular pathology? | Testing is performed on primary tumor or metastasis; insufficient cellularity may require re-biopsy or alternate specimen per pathology. |
| Restaging or progression with potential change to anti-EGFR therapy | Does prior RAS status still apply to the current tumor sample? | New metastatic sites or mixed responses may prompt repeat testing per oncology and pathology policy — nurses verify which specimen date applies to current orders. |
Contraindications and Precautions
There is no absolute contraindication to sending tumor tissue for RAS genotyping. Testing may be inappropriate on the wrong specimen type, without adequate tumor, or when results will not change management — oncology defines timing.
- Acute bowel obstruction, perforation, or massive bleeding — escalate surgical/oncology pathways; do not defer because KRAS/NRAS is pending.
- Anti-EGFR infusion scheduled while a known KRAS or NRAS mutation is documented — hold and notify prescriber/pharmacy per protocol.
- Telling a patient anti-EGFR therapy will work despite a reported RAS mutation on the chart.
- KRAS exon 2 testing alone — extended NRAS and additional KRAS exons must be assayed per ASCO/NCCN extended RAS recommendations.
- Confusing somatic tumor RAS results with germline HBOC genetic testing — different orders, specimens, and counseling pathways.
- Assuming wild-type RAS on an old block when current metastasis drives therapy — confirm specimen source and date with oncology.
- Known RAS mutation with active anti-EGFR order on the MAR — notify prescriber and pharmacy immediately.
- New weight loss, obstruction symptoms, or sepsis physiology while on chemotherapy — escalate clinically regardless of biomarker status.
- Insufficient tumor for RAS testing with anti-EGFR planned imminently — notify oncology and pathology per protocol.
Patient Preparation
Preparation focuses on correct tumor specimen identification, pathology coordination, and MAR verification before anti-EGFR therapy — not fasting or venipuncture for standard FFPE molecular testing.
Pre-test checksReview systemic regimens that may pair with anti-EGFR therapy (for example fluorouracil-based combinations, irinotecan, oxaliplatin per oncology orders). Nurses do not independently remove anti-EGFR drugs — notify prescriber and pharmacy when RAS mutation conflicts with MAR.
Where the test is performed
This page is a Tests & Diagnostics guide for KRAS/NRAS Testing. It emphasizes why the test is ordered, how to interpret results, when to escalate, and preparation factors that affect validity — not step-by-step performance technique (those live under Nursing Procedures when available).
KRAS/NRAS Testing is performed in a CLIA-certified molecular pathology or oncology diagnostics laboratory on tumor tissue (primary colon/rectal tumor or metastasis), typically formalin-fixed paraffin-embedded blocks or unstained slides. Ward and infusion nurses focus on order verification, tumor block tracking with pathology, MAR safety for cetuximab or panitumumab when RAS results are pending or positive, coordinated result notification, and escalation of acute oncology symptoms — not DNA extraction or sequencing technique.
Use the preparation, results, and nursing responsibility sections below for safety checks, interpretation, escalation, and documentation — not equipment operation or departmental imaging protocols.
Result follow-up at a glance
Nursing workflow on this page — from order to safe action on results:
Results and Interpretation
Laboratories report detected KRAS and/or NRAS mutations by gene, exon, and codon, or no mutation detected (RAS wild-type) in the assayed regions. Nurses record the classification reported and ensure oncology interprets anti-EGFR eligibility — including guideline-defined exceptions such as selected KRAS G12C pathways when applicable.
Reference ranges, critical values, and protocols may vary by laboratory, institution, patient population, and testing method. Always follow local policy and the reporting laboratory’s reference range.
| Result | Range / Finding | Clinical Meaning | Nursing Action |
|---|---|---|---|
| Negative / not detected | No KRAS or NRAS mutation detected (extended RAS wild-type) | Tumor lacks detected mutations in assayed KRAS/NRAS exons — anti-EGFR therapy may be considered with oncology when other criteria are met (for example left-sided tumor location and BRAF status per NCCN) | Confirm oncology has reviewed full biomarker panel; proceed with anti-EGFR only per signed orders after pharmacy verification |
| Equivocal / borderline | Insufficient tumor or equivocal assay / QNS specimen | Laboratory cannot reliably classify RAS status — may require repeat block or re-biopsy | Notify oncology and pathology; hold anti-EGFR per protocol until valid RAS status is established |
| Positive / elevated | KRAS and/or NRAS mutation detected (any assayed exon) | Strong negative predictive marker for standard anti-EGFR monoclonal antibody benefit in mCRC per NCCN and ASCO — exceptions require oncology-directed targeted pathways | Notify prescriber and pharmacy; document mutation; ensure anti-EGFR is not administered outside guideline exceptions; support oncology teaching on alternate regimens |
| Not applicable / below detection limit | Not applicable — RAS testing is mutation-detected vs wild-type, not numeric low/high | Not applicable | Not applicable |
Anti-EGFR Holds and Acute Oncology Escalation
KRAS/NRAS results are not numeric critical laboratory values. Urgency is clinical: anti-EGFR administration despite known RAS mutation, invalid QNS specimens with imminent biologic therapy, or acute complication physiology.
| Critical Finding | Threshold / Value | Immediate Action |
|---|---|---|
| RAS mutation with scheduled anti-EGFR infusion | Documented KRAS or NRAS mutation; cetuximab or panitumumab on MAR | Hold biologic per protocol; notify prescriber and pharmacy immediately; document read-back |
| QNS or failed extended RAS assay with anti-EGFR ordered | Insufficient tumor or assay failure; anti-EGFR planned within 24 hours | Notify oncology and pathology; do not assume wild-type; clarify alternative regimen per protocol |
| Acute abdominal catastrophe during treatment workup | Obstruction, peritonitis, massive bleed, or sepsis signs | Escalate according to facility policy — evaluate outcomes after surgical or ICU intervention |
Escalate according to facility policy when anti-EGFR therapy is scheduled despite a known RAS mutation, when RAS status is invalid but biologics are imminent, or when the patient develops acute abdominal or sepsis findings.
Factors Affecting Results
Extended RAS testing has pre-analytic and interpretive limitations. Nurses prevent harm by protecting specimen integrity and avoiding bedside changes to oncology regimens.
- Not applicable in serology sense — false mutation calls are uncommon in validated CLIA labs; sample mix-up or wrong block is the greater risk
- Detecting a subclonal mutation in a small component while another clone drives growth — oncology interprets heterogeneity
- Reporting mutation on non-malignant tissue if tumor enrichment was inadequate
- Limited extended RAS panel — testing only KRAS exon 2 misses NRAS and additional KRAS mutations
- Insufficient DNA from necrotic or scant FFPE tissue — may yield false wild-type if assay fails silently
- Testing outdated primary tumor when untreated metastasis has different RAS status — specimen mismatch
- Decalcified or poorly fixed tissue — may reduce DNA quality per pathology standards
- Wrong patient block or mislabeled slide — verify two identifiers with pathology
- Recent transfusion or allogeneic transplant irrelevant to somatic tumor DNA — ensure tumor not germline buccal mix-up
Extended RAS status predicts anti-EGFR eligibility but does not alone determine all systemic therapy. BRAF, MSI/MMR, sidedness, and other biomarkers may alter plans per NCCN. Liquid biopsy or ctDNA assays may supplement tissue testing per institutional policy — nurses do not substitute bedside interpretation for oncology decisions.
Nursing Responsibilities
Nursing care centers on specimen tracking, MAR safety for anti-EGFR biologics, coordinated result notification, balanced patient teaching, and escalation of acute oncology complications.
Before the TestDocumentation
Documentation should capture specimen details, result classification, anti-EGFR hold actions, notifications, and teaching without implying independent regimen changes.
“Extended KRAS/NRAS genotyping resulted: KRAS G12D mutation exon 2 detected; NRAS wild-type. Cetuximab on MAR held pending oncology review per RAS-positive protocol. Prescriber Dr. Lee and pharmacy notified 09:40 with read-back. Patient taught mutation means anti-EGFR is not expected to help in standard pathways; alternate FOLFIRI plan discussed at oncology visit tomorrow. No acute abdominal symptoms; vitals stable.”
- Specimen site (primary vs metastasis), block ID, and result date
- Extended RAS classification (mutation vs wild-type vs QNS)
- Anti-EGFR hold actions and prescriber/pharmacy notification
- Patient teaching on biomarker-guided therapy (evaluate outcomes at follow-up)
- Pending or concurrent biomarkers (BRAF, MSI) if ordered
- Acute symptom escalation teaching documented
Patient and Family Education
Use clear language aligned with oncology teaching: RAS testing on the tumor helps choose medicines that may work — it is not the same as inherited family cancer gene testing.
KRAS/NRAS Testing NCLEX practice questions
Practice NCLEX-style clinical judgment focused on KRAS/NRAS Testing safety and nursing judgment. Use the case tabs (orders, results, assessment, nursing notes), then answer eight Next Gen–style items (including an ordered workflow step) and evaluate outcomes with the answer key.
Select a tab to view orders, results, assessment, and nursing note details for this case.
- Order: Extended KRAS/NRAS genotyping on FFPE liver metastasis block
- Indication: Newly metastatic colon cancer; oncology considering FOLFIRI plus cetuximab
- Timing: Block sent Monday; molecular result returned Wednesday 07:00
- Related orders: FOLFIRI scheduled Thursday; cetuximab on MAR pending RAS review; BRAF pending
- Result: KRAS G12D mutation exon 2 detected; NRAS no mutation detected (extended panel complete)
- Trend / prior value: Prior KRAS exon 2-only assay from 2019 not on current metastasis — superseded by new block
- Pending tests: Oncology clinic telehealth 14:00 today; pharmacy hold note on cetuximab
- Vital signs: Temp 36.9°C, HR 82/min, BP 118/70, RR 16, SpO₂ 97% on room air
- Symptoms: Fatigue and mild nausea; no acute abdominal pain; last bowel movement yesterday
- Focused assessment: Abdomen soft, non-distended; no rebound; 3-kg weight loss over six weeks
- Preparation notes: Pathology confirmed adequate tumor cellularity; patient believes cetuximab will shrink liver mets regardless of gene result
- Collection events: Correct block ID verified with pathology; CLIA lab accession matched patient identifiers
- Teaching gaps / safety concerns: KRAS mutation on chart with cetuximab still on tomorrow’s MAR until oncology sign-off
Answer key & rationale
Frequently Asked Questions
FAQ
Why is extended KRAS/NRAS testing ordered in metastatic colorectal cancer?
NCCN and ASCO recommend RAS genotyping on tumor tissue in all patients with metastatic colorectal cancer so anti-EGFR monoclonal antibody eligibility is known before ineffective cetuximab or panitumumab exposure. Extended testing includes KRAS and NRAS exons 2, 3, and 4.
Does a KRAS or NRAS mutation mean the patient inherited it from parents?
Usually no. KRAS/NRAS testing for anti-EGFR decisions analyzes somatic mutations in tumor cells acquired during cancer development — not germline hereditary cancer predisposition testing. Counseling pathways differ; clarify with oncology if germline testing is separately ordered.
Can cetuximab or panitumumab be given if any RAS mutation is detected?
In standard metastatic colorectal cancer pathways, NCCN and ASCO indicate patients with known KRAS or NRAS mutations should not receive cetuximab or panitumumab because benefit is essentially absent. Selected KRAS G12C targeted pathways are oncology-defined exceptions — nurses follow signed orders after specialist review.
Is testing only KRAS exon 2 enough?
No. ASCO’s provisional clinical opinion requires extended RAS analysis including NRAS and additional KRAS exons (codons 59, 61, 117, and 146). Mutations outside exon 2 still predict anti-EGFR resistance.
What specimen is used for KRAS/NRAS testing?
Testing is performed on tumor tissue — typically FFPE blocks or slides from primary colon/rectal cancer or metastasis with adequate malignant cells. Performance occurs in CLIA-certified molecular pathology laboratories, not at the bedside.
Should nurses hold anti-EGFR therapy when RAS results are pending?
Follow institutional oncology and pharmacy policy. Many pathways require documented extended RAS status before cetuximab or panitumumab. Nurses clarify with prescriber and pharmacy rather than assuming wild-type status when results are incomplete or QNS.
When should nurses escalate despite pending biomarker results?
Escalate according to facility policy for bowel obstruction, massive bleeding, sepsis, severe anemia, or scheduled anti-EGFR administration when a RAS mutation is already documented. Biomarker timing must not delay acute oncology or surgical evaluation.
References
References
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Allegra CJ; Rumble RB; Schilsky RL. Extended RAS Gene Mutation Testing in Metastatic Colorectal Carcinoma to Predict Response to Anti–Epidermal Growth Factor Receptor Monoclonal Antibody Therapy: ASCO Provisional Clinical Opinion Update. J Clin Oncol. 2016.https://ascopubs.org/doi/10.1200/JCO.2015.63.9674
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National Comprehensive Cancer Network. NCCN Clinical Practice Guidelines in Oncology: Colon Cancer. NCCN.https://www.nccn.org/guidelines/guidelines-detail?category=1&id=1428
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National Library of Medicine. Panitumumab Therapy and RAS and BRAF Genotype. Medical Genetics Summaries. NIH Bookshelf.https://www.ncbi.nlm.nih.gov/books/NBK564800/
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Sepulveda AR; Hamilton SR; Allegra CJ; et al. Molecular Biomarkers for the Evaluation of Colorectal Cancer: Guideline From the ASCP, CAP, AMP, and ASCO. J Mol Diagn. 2017.https://pubmed.ncbi.nlm.nih.gov/27993347/
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National Cancer Institute. Colon Cancer Treatment (PDQ®)–Health Professional Version. NIH.https://www.cancer.gov/types/colorectal/hp/colon-treatment-pdq
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U.S. Food and Drug Administration. Panitumumab (Vectibix) prescribing information. FDA.https://www.accessdata.fda.gov/scripts/cder/daf/index.cfm?event=overview.process&ApplNo=125147
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U.S. Food and Drug Administration. Cetuximab (Erbitux) prescribing information. FDA.https://www.accessdata.fda.gov/scripts/cder/daf/index.cfm?event=overview.process&ApplNo=125084
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College of American Pathologists. Molecular Testing for Colorectal Cancer. CAP.https://www.cap.org/protocols-and-guidelines/cap-guidelines/current-cap-guidelines/molecular-testing-for-colorectal-cancer
Editorial Standards & Medical Review
About the author: Sid A. Abdala Balal, RN, writes evidence-based nursing education focused on diagnostic safety, clinical interpretation, and bedside nursing judgment.
Medical review: This guide is reviewed by Dr. Adam Sayedi, MD, for clinical accuracy, diagnostic safety, and alignment with current standards for KRAS/NRAS Testing.
Policies: Medical Review Process · Editorial Policy · Correction Policy