1Scope & Specimen Types
T
Tissue: fresh frozen · FFPE.
B
Blood: gDNA from PBMC · cfDNA/ctDNA.
U
Urine: exfoliated cells / cfDNA.
F
Fluids/lavage: effusion · BAL · bladder lavage.
S
Stool: cells / DNA.
W
Swab: cervical · uterine · oral.
O
Other: sputum · CSF.
Applies to medical institutions & testing organizations performing tumor methylation assays.
2Pre-Test Requirements
Consent
informed consent
2×10 mL
whole blood for cfDNA
EDTA
no heparin
- Collection: informed consent; minimum volume + backup; hemolyzed/lipemic/icteric blood re-drawn.
- Storage: blood separate 4–6 h (4°C ≤24 h; preservative tube ≤3 d); tissue −70°C or FFPE 3–5 y.
- Swab: dry ≤3 d RT · in solution 2–8°C ≤7 d · −20°C ≤30 d.
- Transport: GB/T 42186 cold-chain box, insulated & leak-proof.
−70°C
tissue storage
3–5 y
FFPE RT
24 h
blood 4°C
4–6 h
blood separation window
≤3 d
preservative tube
≥10 ng/μL
DNA concentration
- Blood rule: never freeze RBC-containing samples before separation.
- Fluids/urine: separated components long-term −70°C; avoid repeated freeze-thaw.
- Stool: preservative solution; ship promptly.
- Consent: explain purpose, method & precautions before collection.
Quality gate before testing: hemolysis rejection · cold-chain compliance (GB/T 42186) · backup specimen for reflex testing.
3Appendix A — Approved Methylation Products (Table A.1)
PAX1 / JAM3 (CISCER)
Cervical brushing · dual-gene combo · cervical cancer screening & triage.
宫颈癌
CDO1 / CELF4 (CISENDO)
Cervical/uterine brushing · dual-gene combo · endometrial cancer detection.
子宫内膜癌
CDO1 / HOXA9
Blood (cfDNA) · dual-gene combo · ovarian cancer diagnosis.
卵巢癌
Appendix A lists approved tumor methylation assays across 11 cancer types — from cervical/endometrial/ovarian to colorectal, gastric, esophageal, liver, lung, bladder, urothelial & glioma.
CervicalEndometrialOvarianColorectalGastricEsophagealLiverLungBladderUrothelialGlioma
4Testing Requirements
qPCR
qPCR: 1–few markers; gene-amplification lab rules.
dPCR
dPCR: trace/low-frequency absolute quantitation.
NGS
NGS: hundreds–whole genome; GB/T 30989.
MS
MALDI-TOF MS: multi-CpG level analysis per kit.
- Extraction: column/magnetic bead; separate cfDNA & cell zones; tumor enrichment if <20% cells; purity OD260/280 1.8–2.0, ≥10 ng/μL.
- Conversion: bisulfite or enzymatic; check efficiency & recovery.
- Detection: SOP per method; cfDNA fragment profile checked for gDNA contamination.
5Post-Test & Quality Control
- Report: patient · specimen (type/QC) · test (method/panel) · results (±/quantitative) · interpretation · limitations · signatures.
- Interpretation: integrate clinical context; grade per guidelines; NMPA items per product standards; multi-gene overall risk score.
1
Internal QC (WS/T 641): control charts, reference materials; correct on out-of-control.
2
EQA (WS/T 644): accredited ring trials; problem list + corrective actions; periodic training.
3
Performance validation: accuracy · precision (intra/inter) · LOD · specificity · reportable range.
5
validation metrics
7
report elements
±/quant
result format
- Limitations: report inherent method limits & evidence level of unclear variants.
- Risk model: overall score/category stability validated for multi-gene panels.
- When: new method/system or major change (reagent/platform/bioinformatics).