Lung Cancer Screening with Low-Dose CT: Who Qualifies, What It Costs, and How to Book

What is a low-dose CT lung cancer screening?

A low-dose CT (LDCT) is a CT scan tuned to use a fraction of the radiation of a standard chest CT — about a fifth. In under 10 minutes, it builds a detailed 3D picture of your lungs that can reveal nodules far too small to show up on a regular chest X-ray, and long before they could cause any symptoms. There are no needles, no contrast dye, and nothing to swallow: you lie on a table, hold your breath for a few seconds, and you're done.

That early look is the whole point. Lung cancer usually causes no symptoms until it has grown or spread, which is why it has historically been found late. Screening changes the odds: in the National Lung Screening Trial, people at high risk who got annual low-dose CT scans were about 20% less likely to die of lung cancer than those screened with chest X-rays. When lung cancer is caught at its earliest stage, it can often be cured with surgery alone.

Here's the surprising part: screening is still one of the most underused preventive tests in the country. The American Lung Association estimates that only about 1 in 6 people who qualify have been screened. That's not because it doesn't work — most people were simply never told they qualify. By reading this page and checking your eligibility, you're already ahead of the curve.

Who should get screened — and how often?

The U.S. Preventive Services Task Force (USPSTF, 2021) gives annual lung cancer screening a Grade B recommendation — the level that requires most insurance plans to cover it as preventive care. You qualify if all three of these apply:

• You're 50 to 80 years old. Medicare uses a slightly narrower window of 50 to 77 for coverage.
• You have a 20+ pack-year smoking history. Not sure what that means? The quick math is in the next section.
• You smoke now, or you quit within the last 15 years. If you quit longer ago than that, guidelines no longer recommend routine screening.

Screening is once a year, every year, while you remain eligible. A single clear scan is reassuring, but it isn't a lifetime pass — the protection comes from the annual rhythm, because a new nodule can appear between scans. Guidelines suggest stopping once you turn 81, once 15 years have passed since you quit, or if a health condition would keep you from wanting or being able to have treatment.

Not sure where you land? Take the 2-minute screening check — it walks through these questions for every major screening at once, and your answers stay on your device.

What's a pack-year? The 30-second math

A pack-year measures how much you've smoked over your lifetime, and the formula is simple: packs per day × years smoked. One pack is 20 cigarettes. All of these add up to the 20 pack-year threshold:

• 1 pack a day for 20 years
• 2 packs a day for 10 years
• Half a pack a day for 40 years

A worked example: say you smoked about a pack and a half a day from age 22 to 40. That's 1.5 packs × 18 years = 27 pack-years — comfortably over the threshold. If you're now between 50 and 80 and you quit within the last 15 years, you'd meet the screening criteria.

If you smoked different amounts during different stretches of your life, add the periods together: a pack a day for 10 years (10 pack-years) plus half a pack a day for 12 years (6 pack-years) comes to 16 pack-years. And if you honestly can't reconstruct the number, don't let that stop you — bring your best estimate to your doctor, and you can work it out together during the shared decision-making visit.

What lung cancer screening costs — with and without insurance

If you meet the USPSTF criteria, annual low-dose CT is usually $0 with insurance. The Affordable Care Act requires most private plans to cover it as preventive care with no copay or deductible, as long as you have a doctor's order and stay in your plan's network.

Medicare Part B covers annual screening at $0 for ages 50–77 who meet the smoking-history criteria — with one extra step: before your first scan, Medicare requires a shared decision-making visit with your doctor or another qualified provider, and that visit is covered too. It can often happen during a regular appointment or by telehealth, and it produces the documented order the imaging center needs.

Paying without insurance? Self-pay low-dose CT typically runs about $99–$400, and many imaging centers offer a simple flat rate for it. That's a notably accessible price for a scan with this much evidence behind it.

Expected Health shows self-pay prices upfront on participating clinics, so you can compare before you book — see clinics and prices near you.

What to expect — from the shared decision-making visit to the scan

Before your first screening, Medicare — and many private insurers — asks for a shared decision-making visit. Don't let the formal name put you off: it's a short, honest conversation with a doctor, nurse practitioner, or physician assistant about what screening can and can't do. You'll cover the benefit of catching cancer early, the chance of a false positive and what follow-up would look like, the small radiation dose, why annual screening matters, and — if you currently smoke — support for quitting if you want it. It's a chance to get your questions answered, not a test you can fail, and it ends with the order you'll need to book.

Scan day is even simpler. There's no preparation: eat normally, take your usual medications, and skip nothing. Wear a top without zippers, snaps, or underwire (or change into a gown at the center). You'll lie on your back on a padded table with your arms above your head while the table glides through an open, donut-shaped ring — not an enclosed tunnel. The technologist will ask you to hold your breath for about 5 to 10 seconds while the scanner captures the images.

There's no contrast dye, no injection, and no recovery time. Most people are in and out of the imaging center in about 15 minutes and drive themselves straight back to their day.

Understanding your results: the Lung-RADS score

A radiologist reads your scan and assigns a score using Lung-RADS, the American College of Radiology's standard reporting system. Your report typically arrives within a few days. Roughly speaking:

• Category 1 or 2 — negative, or only clearly benign findings. This is the result for about 9 in 10 screens. Nothing to do but return in a year.
• Category 3 — a small nodule that's probably benign. The usual plan is simply a repeat low-dose CT in 6 months to confirm it isn't changing.
• Category 4 — a finding suspicious enough to look at sooner, with a short-interval scan, a PET-CT, or a biopsy.

If your report mentions a nodule, take a breath before you worry: small lung nodules are very common, and many are just scars from old infections. More than 9 out of 10 findings flagged for follow-up turn out not to be cancer. Most of the time, "follow-up" means nothing more than another quick scan a few months later.

And if screening does find a cancer, it has done exactly what it's for: screen-detected lung cancers are usually found at stage I, when treatment options are widest and cure is a realistic goal. Your care team will walk you through next steps — you won't be navigating it alone.

The honest trade-offs: false positives, radiation, and overdiagnosis

Screening has real benefits and real trade-offs, and you deserve the actual numbers. False positives are the most common one: under today's Lung-RADS criteria, roughly 1 in 10 screens flags something that needs a second look, and the large majority of those findings prove harmless. Usually that means a follow-up scan; a small share of people go on to a biopsy of what turns out to be benign.

Radiation from a low-dose CT is about 1–1.5 mSv — roughly six months of the natural background radiation everyone receives, and about a fifth of a standard chest CT. Because screening repeats yearly, the dose does add up over time, which is exactly why guidelines reserve it for people whose risk makes the benefit clearly worth it.

Overdiagnosis means finding a cancer so slow-growing it would never have caused harm — it happens in a small share of screen-detected cancers, and it's part of why the shared decision-making conversation exists. Incidental findings are the flip side: the scan also shows the lower neck, heart, and upper abdomen, so reports sometimes mention things like emphysema, thyroid nodules, or calcium in the coronary arteries. Some of that is genuinely useful — coronary calcium is the same signal a calcium score measures on purpose — but it can also mean extra appointments.

The bottom line from the evidence: for people who meet the criteria, the benefit of annual screening clearly outweighs these downsides. That's what the Grade B recommendation means, and it's the honest case your doctor will walk through with you.

How to book your lung cancer screening on Expected Health

1. Search your area — enter your ZIP code to see imaging centers offering low-dose CT lung screening near you.
2. Compare and choose — check self-pay prices, locations, and availability, then pick the clinic that fits.
3. Book online in minutes — request your scan without phone calls or waiting on hold.

For insurance or Medicare to cover the scan, you'll need a doctor's order and a documented shared decision-making visit — each clinic's page shows exactly what's required. If you don't have a regular doctor, a telehealth visit can often take care of the conversation and the order, and self-pay scans are typically simpler to arrange.

One more thought while you're here: screenings tend to cluster in the same seasons of life. If you're in the lung-screening age range, you're also due for colorectal cancer screening — CT colonography is one option worth knowing about. Find lung cancer screening near you and check one more thing off the list.