O-RADS — What It Means on Your Imaging Report
Quick Answer
O-RADS (0–5) is a scoring system used on ovarian and adnexal (the fallopian tubes, ovaries, and nearby tissue) findings from ultrasound or MRI — the category estimates the chance a finding is cancer and tells your doctor what to do next.
What Is O-RADS?
O-RADS stands for Ovarian-Adnexal Reporting and Data System. It was developed by the American College of Radiology (ACR) so that every radiologist describes ovarian and adnexal findings the same way and recommends the same next step. The word adnexal means "referring to the fallopian tubes, ovaries, and tissue around them." Two complementary versions exist: O-RADS US for ultrasound (published in 2020) and O-RADS MRI (published in 2021).
The score grades how likely a specific ovarian or adnexal finding is to be cancer. Before O-RADS, reports of ovarian cysts and masses varied a lot from one radiologist to another, which made it hard for patients and doctors to know what to do next. O-RADS was created to bring consistency to that reporting.
The category itself is not a final diagnosis. It is a structured way to express the chance of cancer for a specific finding and to point to a clear next step.
Categories / Classification
| O-RADS Category | What It Means | Recommended Action |
|---|---|---|
| 0 | Incomplete — more imaging is needed | Repeat or additional imaging is needed before a category can be given |
| 1 | Normal ovary (in patients before menopause) | No further imaging or follow-up is needed for this finding |
| 2 | Almost certainly benign (chance of cancer below 1%) | Typically no further workup is needed; sometimes a short-term follow-up scan is suggested |
| 3 | Low chance of cancer (~1 to under 10%) | Follow-up imaging is usually recommended; in some cases a pelvic MRI is added to look more closely |
| 4 | Intermediate chance of cancer (~10 to under 50%) | Pelvic MRI for further characterization is common, and referral to a specialist in cancers of the female reproductive organs (a gynecologic oncology doctor) is often advised |
| 5 | High chance of cancer (≥50%) | Referral to a gynecologic oncology specialist (a doctor who treats cancers of the female reproductive organs) for treatment planning, often with surgery |
The categories shown are the O-RADS US system; the O-RADS MRI version uses similar risk bands with category numbers 1 through 5.
When You Might See This on Your Report
You will see O-RADS on these scans, when an ovarian or adnexal finding is described:
- Pelvic ultrasound done through the lower belly
- Transvaginal ultrasound done with a small probe inside the vagina, which gives a closer view of the ovaries
- Pelvic MRI, usually ordered to look more closely at a finding first seen on ultrasound
The O-RADS category usually appears in the Impression section of the report, next to the description of the ovarian or adnexal finding.
Should I Be Worried?
It depends on the category, and the most common worry is around O-RADS 3 and O-RADS 4.
- O-RADS 1 describes a normal ovary in a patient before menopause and is not a finding at all.
- O-RADS 2 is almost certainly benign, with a chance of cancer below 1%. This usually means no further workup is needed, or at most a short-term follow-up scan.
- O-RADS 3 is low chance, not zero. The cancer chance is about 1 to under 10%, so most O-RADS 3 findings turn out to be benign. Follow-up imaging — sometimes a pelvic MRI — is the usual next step rather than immediate surgery.
- O-RADS 4 and 5 carry a higher chance of cancer, but the score is not a diagnosis. It grades suspicion, not certainty. A biopsy or surgery may follow, but the imaging score does not confirm cancer by itself.
- O-RADS only applies to ovarian and adnexal findings. If your scan was done for another reason and an ovarian finding came up by chance, your doctor will still walk you through what the score means for your specific situation.
What Should I Do Next?
- Find the O-RADS number in the Impression section of your report (for example, "O-RADS 2" or "O-RADS 4") and write it down exactly as it is written.
- Ask the doctor who ordered the scan to walk you through the specific O-RADS number for your case, including what the chance of cancer is in plain language.
- Clarify whether the recommended next step is a follow-up scan, a pelvic MRI, or a specialist visit, and ask for the date and type of any next scan.
- If your report shows O-RADS 4 or 5, ask about referral to a gynecologic oncology specialist — a doctor who treats cancers of the female reproductive organs — so that the right team is involved early.
- Do not assume O-RADS = cancer diagnosis. Even O-RADS 4 and 5 require further workup, such as MRI or biopsy, to know what the finding actually is. The O-RADS number is a guide to the next step, not the answer itself.