MRI-Guided Biopsy

A needle aimed at what the MRI showed finds more cancer with fewer samples. In the prostate it also leaves one man in four without a biopsy at all.

An MRI-guided biopsy takes tissue from a spot that magnetic resonance imaging has shown and that ultrasound or mammography cannot see well enough to target. Urologists use it most, matching the MRI picture to live ultrasound or working inside the scanner, and breast radiologists use it for lesions that only MRI shows. In the PRECISION trial, the MRI route found clinically significant prostate cancer in 38 percent of men against 26 percent with the standard biopsy, diagnosed fewer harmless cancers, and spared 28 percent of men any biopsy because their MRI was clear.

What an MRI-guided biopsy is

A biopsy proves or rules out cancer. It takes a piece of tissue for a pathologist. Where the needle goes decides what it finds, and for decades it went blind. Ten to twelve cores were taken from the prostate in a fixed pattern under ultrasound, which shows the gland and rarely the tumor. Multiparametric MRI shows the tumor. It combines three kinds of image, anatomy, water movement and blood flow, into one examination, and a radiologist grades each suspicious area from one to five on the PI-RADS scale, where five means cancer is highly likely. Doctors sample areas scored four or five and leave areas scored one or two alone. The MRI-guided biopsy is the step that connects the picture to the needle.

Three ways to aim at a prostate lesion

Once the MRI has marked a target, the needle gets guided in three ways. Open each one.

Who needs one, prostate

Guidelines in Europe and the United States now put the MRI before the first biopsy, and the biopsy is targeted at what the MRI shows. Four situations bring most men to it.

1. A raised or rising PSA with no previous biopsy. The MRI decides whether a biopsy is needed at all. A clear scan with a low PSA density lets many men avoid the needle and return to PSA checks.
2. A negative standard biopsy with a PSA that keeps rising. The old blind biopsy missed something. The MRI shows where, and a targeted biopsy reaches it, which the Cochrane review found detected 44 percent more significant cancers than repeating the systematic biopsy.
3. Active surveillance for a low-risk cancer. Men who are watching a small cancer rather than treating it have an MRI and a targeted biopsy at intervals to confirm that nothing has grown or changed grade.
4. A lesion in the front of the gland. Anterior tumors sit beyond the reach of a standard transrectal biopsy and are found almost only by MRI.

Two groups sit between the lines.

Men with a suspicious MRI and a normal PSA, and men whose MRI is clear while their PSA density is high, are the difficult cases. They need a urologist to weigh the two, and a targeted biopsy alone is sometimes too little for them.

MRI-guided breast biopsy

Doctors use breast MRI to screen women at high genetic risk, to measure the extent of a known cancer before surgery, and to look for a primary tumor when cancer has appeared in a lymph node. It finds lesions that mammography and ultrasound miss. The first step after such a finding is a second-look ultrasound, aimed at the spot the MRI marked, because an ultrasound-guided biopsy is quicker and cheaper. Spick and Baltzer pooled 17 studies with 2,201 MRI-detected lesions and found that second-look ultrasound located 57.5 percent of them, more often when the lesion was a mass and when it was malignant. The rest, more than four in ten, have to be sampled inside the scanner.

What the studies found

The randomized trial. 38% vs 26%, and 28 percent spared a biopsy

In PRECISION, 500 men with a raised PSA and no previous biopsy were randomized to MRI with targeted biopsy only if the scan was suspicious, or to standard transrectal biopsy. Clinically significant cancer was found in 38 percent on the MRI route and 26 percent on the standard route, harmless low-grade cancer was diagnosed 13 percentage points less often, and 71 of 252 men on the MRI route needed no biopsy at all. Kasivisvanathan and colleagues, N Engl J Med, 2018.

The accuracy study. 93% vs 48%

Sensitivity of multiparametric MRI and of standard biopsy for clinically significant cancer in PROMIS, where 576 men had both tests and a saturation template biopsy as the reference. MRI was less specific, at 41 percent. The authors calculated that using MRI as a triage test would let 27 percent of men avoid a biopsy, and 5.9 percent of participants had a serious adverse event from the biopsies, including eight cases of sepsis. Ahmed and colleagues, Lancet, 2017.

Why systematic cores are often kept. 5.2 percent missed without systematic cores, 7.6 percent without targeted cores

In MRI-FIRST, 251 men had both a targeted and a systematic biopsy in the same session, with different operators blind to each other. Each method found significant cancers the other missed. The authors concluded that MRI improves detection but does not yet remove the need for systematic sampling in men having a first biopsy. Rouviere and colleagues, Lancet Oncol, 2019.

The review. Detection ratio 1.44 after a negative biopsy, 1.05 before any biopsy

The Cochrane review by Drost and colleagues pooled 43 studies. Against systematic biopsy, the MRI route found 44 percent more significant cancers in men whose earlier biopsy was negative and about the same number in men having a first biopsy, while diagnosing fewer insignificant ones. The certainty of the evidence was rated low because of the way patients were selected. Cochrane Database Syst Rev, 2019.

The day of the biopsy

Both procedures fit into a morning.

Prostate, from arrival to leaving

An antibiotic tablet before the procedure, or none if the transperineal route through the skin behind the scrotum is used, which carries far less infection risk and is now preferred by many centers. Blood thinners paused on the schedule your doctor set. Local anesthetic, or light sedation on request. The probe is placed, the MRI overlay is aligned, and the cores are taken in 15 to 30 minutes. Some blood in the urine, stool or semen for one to three weeks is normal. Most men are back at the hotel within two hours and can fly the next day.

Breast, from arrival to leaving

No fasting unless sedation is planned. Blood thinners paused as instructed. Face down in the scanner, contrast through a vein, local anesthetic, the vacuum samples, the marker, then pressure on the site and a small dressing. Bruising is common and settles in a week or two. Most women leave within an hour and can fly the next day.

Pathology takes three to five working days.

Risks and side effects

The targeting itself adds no risk. What remains comes with any biopsy of that organ, and for the prostate it depends heavily on the route. A transrectal biopsy passes the needle through the bowel wall, and infection follows in a few percent of men, with the serious cases seen in PROMIS. A transperineal biopsy passes through skin and brings the infection rate close to zero. It costs a little more discomfort. Bleeding in the urine, stool and semen, temporary difficulty passing urine and a brief effect on erections are common to both routes and settle within weeks. For the breast the risks are bruising, a small hematoma, infection at the site and a marker that shifts a few millimeters, none of them frequent, and the contrast agent used for MRI causes a reaction in a very small number of people and is avoided in severe kidney disease.

Days in Istanbul, cost and the trip

How long, and when to fly, and what to send

Three working days cover the length of stay. Day one holds the consultation and, if the MRI has to be repeated or done here, the scan. Day two holds the biopsy. Pathology takes three to five working days, so the results are either given on a fourth or fifth day or explained by video after you have flown home, with the written report and the slides available for a second opinion. Flying the day after the biopsy is fine for both organs, and the visit fits inside any short visa unless you stay on for treatment. Send these before you book.

1. MRI report and images, PSA history with dates, and any earlier biopsy report
2. For the breast, the mammogram, ultrasound and MRI reports, and the date of the last period if relevant to timing
3. A list of medication, with blood thinners marked
4. Allergies, kidney disease and any pacemaker or metal implant, which decide whether MRI and contrast are possible
5. Whether you want sedation, and whether a companion will travel with you

Cost comes next. The MRI itself, if it has to be done or repeated in Istanbul, is the largest item apart from the biopsy. A fusion biopsy costs more than a cognitive one because of the software and the planning, an in-bore biopsy more than a fusion biopsy because of the scanner time, and a breast biopsy inside the scanner more than one under ultrasound. Sedation, the number of targets, pathology with any immunohistochemistry, and a second opinion on outside slides are separate items. Published packages in Istanbul cover the consultation, the biopsy, pathology, an interpreter and transfers, and leave out the hotel, flights and the MRI unless it is named. One coordinator handles the case in English, Arabic, French, Russian, Serbian, Romanian or Spanish, or through an interpreter, sends the appointment confirmation and an invitation letter naming the hospital and the treating doctor ten days before travel, and books the hotel and the transfers. A female radiologist or breast specialist can be requested when you first write, and the department arranges it wherever the rota allows. A quote follows the doctor's review of the MRI, which costs nothing.

Results, and after you fly home

The pathology report leads to one of a small number of next steps. The table gives them for the prostate, where the grading system needs a word of explanation, since pathologists grade the cancer from 1 to 5 in the system of the International Society of Urological Pathology and grade group 1 marks the cancer that guidelines advise watching instead of treating.

This table scrolls sideways on a narrow screen. Swipe or drag to see every column.

Breast results, and once you are back home

A benign result that matches what the MRI showed ends the matter. Some women have a repeat MRI at six months. A high-risk lesion, such as atypical hyperplasia, leads to surgical removal because a minority hide cancer nearby. A cancer result leads to staging and a treatment plan with the breast surgeon and the oncologist, and the marker left at the biopsy site guides the surgery months later. Radiotherapy and chemotherapy are both delivered at Biruni Hospital on the same site if the treatment is planned here.

Once you are back home, the discharge file speaks for you. It holds the MRI report and images, the biopsy report with the grade and the number of positive cores, and a letter in English for your urologist or breast team, and the slides can be sent to a pathologist at home for a second reading. The coordinator stays reachable on the same WhatsApp number. Clinical questions go to the doctor who did the biopsy.

MRI-Guided Biopsy FAQ