Iort

Brief summary: IORT is the application of radiation to a target area during surgery. It may be used in selected cancers, but it is not suitable for every patient and is often planned together with other treatments rather than as a stand-alone solution.

What is intraoperative radiation therapy (IORT)?

Intraoperative radiation therapy, or IORT, is the delivery of radiation directly to a target area during an operation. The basic principle is that after the surgeon removes the visible tumor or reduces disease burden, radiation can be given in a single focused session to tissue at risk for residual microscopic disease. This may help spare some surrounding healthy structures and can sometimes allow selective dosing in areas that are harder to treat optimally with standard external-beam approaches alone. Even so, IORT is usually not an isolated treatment; it is commonly considered as part of a broader plan that may also include surgery, external-beam radiation, and systemic therapy. ^[1][2][4][5]

One of the most frequently discussed applications is breast cancer, but IORT may also be considered in selected gynecologic, gastrointestinal, sarcoma-related, or recurrent tumors. The crucial point is that the answer to “Which cancers can be treated with IORT?” is not the same for every patient. Tumor site, histology, stage, surgical margins, prior radiation, and the position of nearby critical organs all matter. For that reason, IORT is meaningful only when surgical and radiation oncology teams evaluate the case together. ^[1][3][4][5]

In which situations is it considered?

IORT may be particularly useful when the tumor bed can be clearly identified during surgery and when direct treatment of that area offers a practical advantage. In some selected early breast cancer cases, for example, a single intraoperative dose after tumor excision may be discussed. In other settings—such as areas with substantial local recurrence risk or regions in which protection of surrounding tissue is especially important—this approach may also be considered. Suitability criteria differ by disease and by center, and patient selection is one of the key determinants of outcome. ^[1][3][4][6]

Not every cancer is appropriate for IORT. In some settings, standard external-beam radiation remains better established and supported by stronger evidence. Even in breast cancer, long-term recurrence outcomes and selection criteria must be interpreted carefully. IORT should therefore not be viewed as “better simply because it is shorter.” Convenience, side-effect profile, local control, life expectancy, and multidisciplinary judgment all matter. ^[3][4][5][6]

How is it performed and how does the process work?

Planning begins well before the day of surgery. The surgeon, radiation oncologist, medical oncologist, and when necessary radiology and pathology teams work together. During the operation, after the tumor has been removed, the target area is identified. Nearby structures that should be protected—such as bowel, vessels, nerves, or skin—may be displaced or shielded as appropriate. The selected device and applicator are then positioned, and radiation is delivered to the target area for the planned dose and duration. ^[1][4][5]

From the patient’s perspective, IORT is not separately felt because it is given during surgery under anesthesia. However, it may lengthen the total time in the operating room, and postoperative care is shaped mainly by the surgery itself. In some patients, IORT is not considered sufficient on its own and additional external-beam radiation or systemic treatment may still be recommended. It should therefore be understood as one component of treatment rather than the entire treatment course. ^[1][3][7]

Advantages, possible risks, and limitations

A major potential advantage of IORT is the ability to deliver a focused dose directly to the target area while potentially reducing exposure to some surrounding healthy tissues. In selected patients, it may also shorten the overall treatment timeline or reduce the number of later radiation sessions. These advantages are meaningful only in correctly selected cases, however. If tumor biology or recurrence risk is not favorable, short-term convenience may not translate into the best long-term oncologic outcome. ^[1][4][5]

Risks vary according to the treated region. Wound-healing delay, fat necrosis, fibrosis, pain, seroma, skin changes, or problems involving nearby organs may occur. Some reports also suggest caution regarding local recurrence risk in patients who are not optimally selected. This is why the limits of IORT need to be understood clearly. The technology can be valuable, but it does not replace standard therapy in every case. ^[4][5][6][7]

Who should seek detailed specialist discussion?

Patients who are offered IORT should ask what role it is expected to play in their specific treatment plan. Is the aim to reduce local recurrence risk, spare surrounding tissue, shorten the treatment timeline, or address a technically challenging tumor bed? Those answers depend on the disease and the patient. This becomes especially important in people who have had prior radiation to the same region, tumors in anatomically difficult areas, or recurrent disease. ^[1][2][5]

After surgery, high fever, rapidly worsening redness, foul-smelling drainage, marked swelling, severe pain, bleeding, shortness of breath, or new organ-related dysfunction may require urgent assessment. These warnings are not always specific to IORT itself; they may also reflect complications of surgery or cancer treatment more broadly. For that reason, discharge instructions, wound care, pathology results, and the need for additional therapy should all be discussed in detail with the treating team. ^[1][4][7]

Why is the decision personalized?

One of the most important questions for patients is how IORT would actually change their treatment strategy. In some patients it can be a strong component of local control. In others, it may not fully replace the role of standard external-beam radiation. Final pathology, margin status, nodal findings, and tumor biology may alter the plan even after initial approval for IORT. Individual oncologic safety should always take priority over procedural convenience. ^[1][3][5][6]

Individual risk, suitability, and follow-up planning vary according to the procedure, coexisting medical conditions, and medications; the final decision should therefore be made with the relevant specialist team.