Choosing the modality
| Situation | First test |
|---|---|
| Palpable lump, < 30 years (some guidelines < 35), pregnant or lactating | ultrasound |
| Palpable lump, ≥ 30–40 | diagnostic mammography + targeted US |
| Screening, average risk | mammography (typically from 40–50, every 1–2 years; programmes vary; India: clinical breast examination‑based screening in NPCDCS/NP‑NCD, mammography where available) |
| High risk (BRCA1/2, TP53, chest RT < 30 y, lifetime risk ≥ 20%) | annual MRI + mammography |
| Dense breasts | supplemental US or MRI; digital breast tomosynthesis improves detection |
| Implant rupture | MRI (linguine sign intracapsular; snowstorm on US extracapsular) |
| Extent of known cancer, occult primary (axillary node), response to neoadjuvant therapy | MRI |
| Nipple discharge | US ± mammography; (galactography historical) |