Sputum Cytology

Testing Laboratory

Department

Cytology

Delphic Registration Code (Alpha Code)

NGYN

Test Code (Numeric Code)

9034

Laboratory Handling

Transport

Send specimens to the laboratory immediately after collection. If immediate transport is not possible, store at 4°C (approximately 3–6°C).

Sample Stability

Refrigeration of fresh specimens temporarily preserves cells by slowing their metabolic processes. At room temperature (22–25°C), specimen integrity is maintained for approximately 6 hours before significant deterioration occurs. When stored at 4°C, specimen integrity can be maintained for up to 24 hours.

Synonyms

Cytology

Turnaround Time

5 days

80% reported within 5 working days, we follow the RCPA guidelines.

Specimen Type

• Sputum

Specimen Requirements

Tube/Container Type:

Preferred

• Specimen Container

Paediatric Specimen Requirements

Tube/Container Type:

Preferred

• Specimen Container

Pre-testing Requirements

Patient should cough deeply and expectorate sputum (not saliva) into a sterile container.
- Early morning specimens (before breakfast and teeth washing) are preferred for sputum cytology.
- Three specimens are recommended for cancer detection; up to five specimens may be submitted when exclusion of malignancy is required.
- For induced sputum, bronchodilator administration and nebulised saline inhalation may be used according to institutional protocols.

Test Method

Traditional pick and smear method OR liquid-based cytology preparation.

Limitations / Interference

Sensitivity of Sputum Cytology for lung cancer detection is variable and generally low. It depends on specimen quality, collection technique, tumour size and location, and the number of specimens submitted. A negative sputum cytology result does not exclude malignancy and should be interpreted in conjunction with clinical and radiological findings.

Salivary contamination may further reduce specimen adequacy and diagnostic sensitivity.

Uncertainty of Measurement

Uncertainty of measurement is not applicable to sputum cytology, as the test provides a qualitative result based on cytomorphological interpretation rather than quantitative measurement.

Contact Information