Cyfra - Lung Cancer Marker

CYFRA 21‑1 is a blood tumor marker made of soluble fragments of cytokeratin 19 released from dying epithelial tumor cells. It’s mainly used in non‑small‑cell lung cancer—especially squamous cell type—to aid prognosis, monitor treatment response and detect recurrence. Levels may also rise with other cancers or benign lung diseases, so results are interpreted alongside imaging and clinical findings.

CA125 (cancer antigen 125) is a blood tumor marker mainly known for ovarian cancer but can be elevated in some lung cancers, especially adenocarcinoma or when the pleura is involved. It is neither sensitive nor specific for diagnosis, but rising levels may indicate advanced disease, pleural effusion, or progression and can help monitor response to treatment alongside imaging.

The CYFRA 21‑1 test measures fragments of cytokeratin 19 in blood as a tumor marker. It’s mainly used in lung cancer, especially non‑small cell (squamous), to help with diagnosis, assess prognosis, monitor treatment response and detect recurrence. Levels can be raised in other cancers or benign lung disease, so it isn’t a standalone screening test and must be interpreted with clinical and imaging findings.

CYFRA 21‑1 has moderate sensitivity for detecting non‑small cell lung cancer—typically around 50–70%, higher in squamous‑cell histology. Sensitivity depends on assay cut‑offs, stage and tumor burden, so it cannot rule out cancer alone. It’s most useful combined with imaging and other markers, and for monitoring treatment response or recurrence rather than as a standalone diagnostic test.

Costs vary by country and provider. In India the CYFRA 21‑1 test typically costs about ₹500–₹2,000 at private labs. In the US it commonly ranges from roughly $30–$150 if paid privately; in the UK it’s usually covered by the NHS when clinically required, but private testing can be £30–£100. Final price depends on lab, whether it’s part of a panel, and insurance.

CYFRA 21-1 is moderately accurate for non‑small‑cell lung cancer (especially squamous cell). Sensitivity is modest (roughly 40–70%) while specificity is higher (about 80–95%), so it’s more useful for prognosis and monitoring treatment response than for screening. Levels can also rise in other cancers and benign lung disease, so results need correlation with imaging and clinical findings.