On May 17, 2026 ImPact Biotech, a clinical-stage biotechnology company focused on developing Padeliporfin Vascular Targeted Photodynamic therapy (VTP) to treat a range of solid tumors, reported updated results from ENLIGHTED, the Company’s ongoing Phase 3 study of Padeliporfin VTP treatment in patients with low-grade upper tract urothelial carcinoma (UTUC). These data will be shared during a podium presentation and in an interactive poster at the American Urological Association (AUA) Annual Meeting taking place May 15-18, 2026, in Washington, D.C.

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"These updated efficacy and durability results from the Phase 3 ENLIGHTED trial continue to reinforce Padeliporfin VTP’s potential to become an attractive alternative, minimally invasive ureteroscopic treatment option for patients with low-grade UTUC," said Eyal Morag, M.D., Chief Medical Officer of ImPact Biotech. "The promising complete response rate and encouraging durability observed to date, alongside a well-established safety profile, further support the opportunity to provide a meaningful organ-sparing treatment for patients with limited options in UTUC and additional solid tumor indications. We look forward to sharing topline data from ENLIGHTED later this year and preparing for regulatory submission in 2027, while exploring strategic opportunities to commercialize the program and maximize Padeliporfin VTP’s impact for UTUC patients facing great unmet need."

Key updated results from the ongoing Phase 3 ENLIGHTED study of Padeliporfin VTP:

As of April 20, 2026, the data cut-off for the poster presentation at AUA 2026, 82 patients had begun treatment, of which 72 had completed PRE and were evaluable for efficacy.

Efficacy Profile:

Overall response rate: 88%
50 of the 72 (70%) response-evaluable patients achieved a CR at the end of PRE.
13 of the 72 (18%) response-evaluable patients achieved a partial response (PR) at the end of PRE.

Durability Profile:

18 of the 21 (85.7%) response-evaluable patients who completed the Maintenance Treatment Phase (MTP) sustained CRs in the treated area for at least 12 months as of the data cutoff date, with additional patients ongoing the MTP that have yet to complete the 12-month evaluation period. Padeliporfin VTP treatment has demonstrated evidence of efficacy and durability.
The current median duration of response (DoR) in the treated area for evaluable patients is 23.9 months based on available follow-up, with ongoing responses still being observed.

Safety and Tolerability Profile:

Padeliporfin VTP was well-tolerated with a safety profile consistent with the previous data obtained from the Phase 1 study and previously announced preliminary Phase 3 results. Padeliporfin VTP treatment has demonstrated a consistent and acceptable safety profile.
Adverse events (AEs): the majority of treatment-emergent adverse events (TEAEs) were mild or moderate, primarily related to the ureteroscopic procedure, and resolved within a few days. Two patients had Grade 3 serious adverse events related to VTP treatment which resolved within two days. No TEAEs of special interest were reported and no TEAE led to discontinuation of the study treatment.

While the Company is pursuing strategic partnering opportunities to support the commercialization of its low-grade UTUC program, ImPact recently presented initial data supporting the advancement of Padeliporfin VTP in locally advanced pancreatic ductal adenocarcinoma (LA-PDAC) at the Society of Interventional Radiology (SIR) 2026 Annual Meeting, which demonstrated a consistent tolerability profile alongside early signs of clinical efficacy, showing potential to convert patients with unresectable stage III LA tumors to surgically resectable candidates.

Additional updates from both programs will be presented at the American Society for Clinical Oncology (ASCO) (Free ASCO Whitepaper) Annual Meeting, taking place May 29 – June 2, 2026, in Chicago, IL.

AUA Presentation Details:

Interactive Poster Title: The ENLIGHTED Phase 3 Trial: Advancing Treatment of Low-Grade Upper Tract Urothelial Carcinoma (LG UTUC) with Padeliporfin Vascular-Targeted Photodynamic Therapy (VTP)
Presenter: Vitaly Margulis, M.D., Professor of Urologic Oncology, University of Texas Southwestern Medical Center
Poster Number: IP30-04
Session Title: Bladder Cancer: Upper Tract Transitional Cell Carcinoma I
Session Date & Time: Saturday, May 16, 2026 at 7:00 AM ET

Podium Presentation Title: ENLIGHTED Phase 3 Trial of Non-Thermal, Drug-Activated Padeliporfin Vascular-Targeted Photodynamic Therapy (VTP) for Low-Grade Upper Tract Urothelial Carcinoma (LG UTUC)
Presenter: Jonathan Coleman, M.D., Urologic Surgeon, Memorial Sloan Kettering Cancer Center
Session Title: Clinical Trials in Progress: Bladder Cancer
Session Date & Time: Sunday, May 17, 2026 at 9:16 AM ET

About ENLIGHTED
The Phase 3 ENLIGHTED study is a single arm, non-randomized, open-label, pivotal trial evaluating Padeliporfin VTP for the treatment of low-grade UTUC. Across 29 clinical sites globally, ImPact is targeting enrollment of up to 100 patients with new or recurrent low-grade, non-invasive UTUC of
the kidney or ureter. The study consists of two parts – an Induction Treatment Phase (ITP) and Maintenance Treatment Phase (MTP) – across which Padeliporfin, a photosensitizing drug, is administered intravenously and VTP therapy is performed, via an ureteroscopy which applies a laser fiber illumination for 10 minutes in the proximity of the tumor, leading to local activation of Padeliporfin in the tumor. ITP consists of one-to-three treatments with VTP therapy at four-week intervals or until a complete response (CR) is achieved; MTP follows with standard-of-care treatment alongside VTP therapy administered every three months for up to 12 months. The study’s primary objective is to assess the response rate to Padeliporfin VTP treatment at the end of ITP, with secondary objectives evaluating safety, tolerability and duration of response.

(Press release, ImPact Biotech, MAY 17, 2026, View Source [SID1234665816])

On May 17, 2026 NANOBIOTIX (Euronext: NANO – NASDAQ: NBTX – the "Company"), a late-clinical stage biotechnology company pioneering nanotherapeutic approaches to expand treatment possibilities for patients with cancer and other major diseases, reported the presentation of Part 1 data from the CONVERGE study, a Johnson & Johnson-sponsored randomized Phase 2 clinical trial evaluating potential first-in-class Nanoradioenhancer JNJ-1900 (NBTXR3) for patients with stage 3 inoperable non-small cell lung cancer ("NSCLC"), at the 2026 European Society for Radiotherapy and Oncology Annual Meeting (ESTRO 2026).

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PRESENTATION #116: Radiographic Response in Patients with Stage III Unresectable Non-Small Cell Lung Cancer Treated with an Intratumoral Radioenhancer (JNJ-90301900)

Jeffrey Bradley,1 Benjamin T. Cooper,2 Sushma Patel,3 David DiBardino,4 Michael Pritchett,5 Kevin C. Ma,4 Isaac Laniado,6 Melina E. Marmarelis,7 Matthew Scarlotta,8 Joshua K. Sabari,9 Yi -Wen Ma,10 Tori Stromp,10 Yina Kuang,10 Balaji Laxmanan,10 Kiran Devisetty,10 Steven Feigenberg1

Study Conclusions

Early results suggest that intratumoral/intranodal injection of JNJ-1900 (NBTXR3) is feasible and can be performed safely in patients with stage III unresectable NSCLC
Initial efficacy responses observed in 7 patients following the full treatment regimen of concurrent chemoradiotherapy, JNJ-1900 (NBTXR3), and consolidation with durvalumab are promising:
Overall response rate ("ORR") = 85.7% (6/7 patients)
Complete response rate ("CRR") = 57.1% (4/7 patients)
With the current standard of care, concurrent chemoradiation therapy (cCRT) ± durvalumab, depth of response remains limited in Stage 3 Inoperable NSCLC with very low rates of complete response (<5%) *
Disease control rate ("DCR") = 100.0% (7/7 patients)
Absence of progressive disease and deepening response over time suggests potential for long-term durability
1Radiation Oncology, University of Pennsylvania, Philadelphia, USA; 2Radiation Oncology, NYU Langone Health, New York, USA; 3Radiation Oncology, FirstHealth of the Carolinas, Pinehurst, USA; 4University of Pennsylvania, Philadelphia, USA; 5Interventional Pulmonology, FirstHealth of the Carolinas, Pinehurst, USA; 6Interventional Pulmonology, NYU Langone Health, New York, USA; 7Medical Oncology, University of Pennsylvania, Philadelphia, USA; 8Medical Oncology, FirstHealth of the Carolinas, Pinehurst, USA; 9Medical Oncology, NYU Langone Health, New York, USA; 10Johnson & Johnson, New Brunswick, NJ, USA

* Antonia SJ, et al. N Engl J Med. 2017.

About JNJ-1900 (NBTXR3)

JNJ-1900 (NBTXR3) is a novel, potentially first-in-class oncology product composed of functionalized hafnium oxide nanoparticles that is administered via one-time intratumoral injection and activated by radiotherapy. Its proof-of-concept was achieved in soft tissue sarcomas through a successful randomized Phase 2/3 study in 2018. The product candidate’s mechanism of action (MoA) is designed to induce significant tumor cell death in the injected tumor when activated by radiotherapy, subsequently triggering adaptive immune response and long-term anti-cancer memory. Given the physical MoA, Nanobiotix believes that JNJ-1900 (NBTXR3) could be scalable across any solid tumor that can be treated with radiotherapy and across any therapeutic combination, particularly immune checkpoint inhibitors.

Radiotherapy-activated JNJ-1900 (NBTXR3) is being evaluated across multiple solid tumor indications as a single agent or combination therapy. The program is led by NANORAY-312—a global, randomized Phase 3 study in locally advanced head and neck squamous cell cancers. In February 2020, the United States Food and Drug Administration granted regulatory Fast Track designation for the investigation of JNJ-1900 (NBTXR3) activated by radiation therapy, with or without cetuximab, for the treatment of patients with locally advanced HNSCC who are not eligible for platinum-based chemotherapy—the same population being evaluated in the Phase 3 study.

Given the Company’s focus areas, and balanced against the scalable potential of NBTXR3, Nanobiotix has engaged in a collaboration strategy to expand development of the product candidate in parallel with its priority development pathways. Pursuant to this strategy, in 2019 Nanobiotix entered into a broad, comprehensive clinical research collaboration with The University of Texas MD Anderson Cancer Center to sponsor several Phase 1 and Phase 2 studies evaluating JNJ-1900 (NBTXR3) across tumor types and therapeutic combinations. In 2023, Nanobiotix announced a license agreement for the global co-development and commercialization of JNJ-1900 (NBTXR3) with Janssen Pharmaceutica NV, a Johnson & Johnson company.

(Press release, Nanobiotix, MAY 17, 2026, View Source [SID1234665815])

On May 17, 2026 Ferring Pharmaceuticals reported a new real-world case series demonstrating that re-induction with ADSTILADRIN (nadofaragene firadenovec-vncg) resulted in complete responses (CR) in approximately 31% (4/13) of patients with high-risk Bacillus Calmette-Guérin (BCG)-unresponsive non-muscle invasive bladder cancer (NMIBC) who did not respond to an initial dose of therapy. The study included patients with carcinoma in situ (CIS), with or without papillary tumors (±Ta/T1).

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The findings – presented at the 2026 American Urological Association (AUA) Annual Meeting and scheduled for publication in Translational Andrology and Urology later in May – reflect outcomes observed following a re-induction dose (second dose overall) of ADSTILADRIN in a real-world clinical setting, including two patients (2/13) with CIS with papillary disease (T1).1

ADSTILADRIN is the first and only non-replicating intravesical gene therapy approved by the U.S. Food and Drug Administration (FDA) for the treatment of patients with high-risk BCG-unresponsive NMIBC with CIS, with or without papillary tumors (±Ta/T1), and is administered once every three months.

"These findings offer a promising signal that some patients who do not achieve a complete response after an initial dose of ADSTILADRIN may still benefit from re-induction," said Chad Reichard, MD, urologic oncologist and Director of Oncology at Urology of Indiana. "Real-world evidence provides important insight into how ADSTILADRIN is being used in routine clinical practice, and the responses observed in this study support the feasibility of re-induction as a potential option for certain patients despite an initial non-response, while highlighting the need for further study."

The retrospective, observational cohort study analyzed electronic health record data from U.S. private urology practices. Thirteen patients with BCG‑unresponsive NMIBC were eligible, including eight with CIS alone, two with CIS and papillary disease (Ta), and three with CIS and papillary disease (T1). Patients had a mean age of 77.5 years; all were male and had received a mean of 11 prior BCG doses. Prior treatments included gemcitabine (n=4) and pembrolizumab (n=5). Median follow‑up following re‑induction was 379 days (range, 135–519). After re‑induction, four patients (30.8%) achieved a complete response, including two patients with CIS and T1 disease.

Among patients who achieved a complete response, three went on to receive additional doses of ADSTILADRIN; one patient has maintained a complete response at last follow‑up. One patient experienced progression to muscle‑invasive disease (T2a), and one patient underwent cystectomy approximately 51 weeks after initiation of therapy. At the time of analysis, no patient deaths had been reported.

"These new data add to the growing body of real-world evidence generated in urology practices and help inform how re-induction with ADSTILADRIN is being evaluated outside of the controlled clinical trial setting, particularly in a heavily pretreated patient population," said Daniel Shoskes, MD, MSc, FRCS(C), Vice President, Global Medical Director Uro-Oncology, Ferring Pharmaceuticals. "In the Phase 2 and Phase 3 clinical trials, patients who did not achieve a complete response at three months were not retreated with ADSTILADRIN. However, re-induction is an approach that has been used with some immune-based therapies. These real‑world findings provide insight into how re-induction may improve complete response outcomes over the course of treatment."

About Non-Muscle Invasive Bladder Cancer (NMIBC)
NMIBC is a form of bladder cancer that is found in the inner layer cells of the bladder and does not invade into or beyond the muscle wall.2 In the United States, bladder cancer is the sixth most common cancer,3 fourth among men,4 and it is estimated that there will be approximately 84,870 new cases of bladder cancer in the U.S. in 2025.4 Historically, 75% of bladder cancer presents as NMIBC.5 In patients with high-risk NMIBC, intravesical BCG remains the first-line standard-of-care; however, approximately one third of patients with NMIBC will not respond to BCG therapy and 50% of those with an initial response will experience recurrence or progression of their disease.6 Current treatment options for BCG-unresponsive patients are very limited and National Comprehensive Cancer Network (NCCN) guidelines recommend cystectomy (partial or complete removal of the bladder).7

About ADSTILADRIN
ADSTILADRIN (nadofaragene firadenovec-vncg) is the first and only FDA-approved intravesical non-replicating gene-therapy for the treatment of adult patients with high-risk Bacillus Calmette-Guérin (BCG)-unresponsive non-muscle invasive bladder cancer (NMIBC) with carcinoma in situ (CIS) with or without papillary tumors (±Ta/T1). It is a non-replicating adenovirus vector-based therapy containing the gene interferon alfa-2b, administered locally as a monotherapy by catheter directly into the bladder once every three months. The vector enters the cells of the bladder wall, releasing the active gene and causing the bladder’s cell walls to secrete high and transient local expression of interferon alfa-2b protein, a naturally occurring protein the body uses to fight cancer. This approach essentially turns the bladder wall cells into interferon microfactories, enhancing the body’s own natural defenses against the cancer.

ADSTILADRIN has been studied in a clinical trial program that includes 157 patients with high-risk, BCG-unresponsive NMIBC, who had been treated with adequate BCG previously and did not see benefit from additional BCG treatment (full inclusion criteria published on clinicaltrials.gov: NCT02773849 and final five-year follow-up analysis published in The Journal of Urology).8-9

INDICATION
ADSTILADRIN is a non-replicating adenoviral vector-based gene therapy indicated for the treatment of adult patients with high-risk Bacillus Calmette-Guérin (BCG)-unresponsive non-muscle invasive bladder cancer (NMIBC) carcinoma in situ (CIS) with or without papillary tumors (±Ta/T1).

IMPORTANT SAFETY INFORMATION

CONTRAINDICATIONS: ADSTILADRIN is contraindicated in patients with prior hypersensitivity reactions to interferon alfa or to any component of the product.

WARNINGS AND PRECAUTIONS:

Risk with delayed cystectomy: Delaying cystectomy in patients with BCG-unresponsive CIS could lead to development of muscle invasive or metastatic bladder cancer, which can be lethal. If patients with CIS do not have a complete response to treatment after 3 months or if CIS recurs, consider cystectomy.
Risk of disseminated adenovirus infection: Persons who are immunocompromised or immunodeficient may be at risk for disseminated infection from ADSTILADRIN due to low levels of replication-competent adenovirus. Avoid ADSTILADRIN exposure to immunocompromised or immunodeficient individuals.
DOSAGE AND ADMINISTRATION: Administer ADSTILADRIN by intravesical instillation only. ADSTILADRIN is not for intravenous use, topical use or oral administration.

USE IN SPECIFIC POPULATIONS: Advise females of reproductive potential to use effective contraception during ADSTILADRIN treatment and for 6 months after the last dose. Advise male patients with female partners of reproductive potential to use effective contraception during ADSTILADRIN treatment and for 3 months after the last dose.

ADVERSE REACTIONS: The most common (>10%) adverse reactions; including, laboratory abnormalities (>15%), were increased glucose, instillation site discharge, increased triglycerides, fatigue, bladder spasm, micturition (urination urgency), increased creatinine, hematuria (blood in urine), decreased phosphate, chills, pyrexia (fever) and dysuria (painful urination).

You are encouraged to report negative side effects of prescription drugs to FDA. Visit View Source or call 1-800-332-1088. You may also contact Ferring Pharmaceuticals at 1-888-FERRING.

Please click to see the full Prescribing Information.

(Press release, Ferring Pharmaceuticals, MAY 17, 2026, View Source [SID1234665813])

On May 17, 2026 Novartis reported new data from PSMAddition demonstrating improved prostate-specific antigen (PSA) responses with Pluvicto (lutetium (177Lu) vipivotide tetraxetan) combined with standard of care (SoC) in PSMA-positive metastatic hormone sensitive prostate cancer (mHSPC). Data were presented as a rapid oral presentation at the American Urological Association Annual Meeting 2026.

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Results show that patients treated with Pluvicto experienced a higher frequency and depth of PSA response when combined with SoC (androgen receptor pathway inhibitor [ARPI] + androgen deprivation therapy [ADT]) compared to SoC alone. Risk of PSA progression was 58% lower (HR 0.42; 95% CI: 0.30-0.59) in patients treated with Pluvicto plus SoC compared to SoC alone.

"Our goal in hormone-sensitive prostate cancer is to attack and delay the cancer before it develops resistance," said Fred Saad, Professor and Chairman, Department of Surgery, University of Montreal. "The deep and durable PSA response observed by combining 177Lu-PSMA-617 with today’s standard of care, together with earlier reported rPFS data, suggest that treatment intensification with radioligand therapy may help patients delay disease progression."

Nearly all patients (>98%) in both arms had substantial declines in PSA levels. However, more patients treated with Pluvicto plus SoC achieved a deep PSA reduction than those treated with SoC alone, as measured by PSA nadir of <0.2 ng/mL.

Time from randomization Patients with PSA <0.2 ng/mL

Pluvicto + ARPI + ADT ARPI + ADT
Week 12 47.6% (235/494) 37.7% (169/448)
Week 24 73.7% (334/453) 59.7% (250/419)
Week 48 87.4% (320/366) 74.9% (295/394)
These results were observed at the second interim analysis for PSMAddition. The safety profile and tolerability of Pluvicto were consistent with its established profile in PSMAfore and VISION. Grade ≥3 adverse events (AEs) were reported in 50.7% of patients in the Pluvicto plus SoC arm, compared to 43% on SoC alone. The most common all-grade AEs were dry mouth, fatigue, nausea, hot flush and anemia.

"These data show that combining Pluvicto with today’s standard of care resulted in deeper PSA responses than ADT plus ARPI alone," said Mark Rutstein, M.D., Global Head, Oncology Development, Novartis. "As the field moves toward more precision-based approaches and earlier treatment intensification in mHSPC, we are encouraged by the potential for Pluvicto to redefine the standard of care across metastatic prostate cancer."

Novartis has filed regulatory submissions in the United States, China and Japan, with first decisions expected in H2 2026.

PSA progression signals disease resistance
PSA progression can be an early indicator of emerging disease resistance, and approximately one-third of patients do not achieve undetectable PSA levels with SOC alone3. Progression to mCRPC, which typically happens within 20 months of diagnosis, is associated with significantly worse outcomes and a life expectancy less than two years4-7. Approximately 186,000 men are diagnosed with mHSPC each year across the US, China, Japan, France, Germany, Italy, Spain and the United Kingdom1.

About Pluvicto (lutetium (177Lu) vipivotide tetraxetan)
Pluvicto is an intravenous RLT that combines a targeting compound (a ligand) with a therapeutic radionuclide (a radioactive particle, in this case lutetium-177). After administration into the bloodstream, Pluvicto binds to PSMA-expressing target cells, including prostate cancer cells that express PSMA, a transmembrane protein. Once bound, energy emissions from the radioisotope damage the target cells and nearby cells, disrupting their ability to replicate and/or triggering cell death.

Pluvicto is the only PSMA-targeted agent approved for PSMA+ mCRPC and is the first RLT to demonstrate a clinical benefit for patients with PSMA+ mHSPC in a Phase III trial. Novartis is investigating Pluvicto in oligometastatic prostate cancer, an earlier stage of disease, in the PSMA-DC trial (NCT05939414).

Educational Resources for RLT
To support the integration and safe administration of Novartis RLT products across urology and oncology, Novartis created the RLT Institute. The Institute provides educational resources on theranostics, safety and licensing, facilities and equipment, and clinical workflows to support urologists, oncologists and multidisciplinary teams as they prepare for and integrate RLT into patient care.

(Press release, Novartis, MAY 17, 2026, View Source [SID1234665811])

On May 17, 2026 EORTC reported final results from a landmark EORTC randomised trial with more than 20 years of follow-up show that irradiation of the internal mammary and medial supraclavicular lymph nodes reduces breast cancer mortality but does not improve overall survival. The findings highlight the importance of very long-term follow-up when evaluating cancer treatments, particularly in patients with otherwise favourable prognosis.

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The results stem from EORTC trial 22922/10925 and were presented at the ESTRO 2026 Congress in Stockholm during the plenary session: Joint Green Journal – The Lancet Oncology Top Clinical Trials. Reflecting the strength and clinical relevance of these findings, the planned 20-year analysis of the full trial population has been simultaneously published in CA: A Cancer Journal for Clinicians, while The Lancet Oncology has accepted to publish soon a complementary paper reporting an unplanned subset analysis in the patients with node-negative (pN0) breast cancer.

Between 1996 and 2004, the trial enrolled 4,004 patients with stage I–III breast cancer at 46 centres in 13 countries. Patients were randomised to receive postoperative radiation therapy with or without elective irradiation of the internal mammary and medial supraclavicular (IM-MS) lymph nodes. At final analysis, the median follow-up was 22.2 years — the longest planned, as well as median, follow-up of any randomised breast cancer radiation therapy trial.

Long‑term outcomes across the overall trial population
At 20 years, overall survival was similar in patients treated with or without IM-MS irradiation. However, breast cancer–related mortality was significantly lower among patients who received IM-MS irradiation. This benefit was counterbalanced over time by an increase in deaths from causes other than breast cancer, which emerged after approximately 15 years, resulting in no survival advantage.

Long-term cardiac and pulmonary toxicity was reported more frequently after IM-MS irradiation, although severe side effects remained very uncommon. Of note, patients were treated using radiation therapy techniques available more than two decades ago.

Outcomes in node-negative breast cancer patients
The proffered paper presented at ESTRO also included the subset analyses on the 1,778 patients with node-negative (pN0) breast cancer and centrally or medially located tumours. Despite a lower absolute risk of breast cancer death in this group, the long-term pattern closely mirrored that of the overall trial population.

Reductions in breast cancer mortality were again offset by a later increase in non–breast cancer–related deaths, resulting in no improvement in overall survival. These findings suggest that long‑term trade‑offs must be considered even in patients with a favourable prognosis and call for careful evaluation of nodal irradiation in axillary‑node‑negative disease.

"Such large, decades-long trials with rigorous quality assurance, allowing clinically meaningful subgroup analyses, are only possible thanks to the sustained support and collaboration fostered by organisations like EORTC," agreed both study coordinators.

The investigators note that advances in modern radiation therapy planning and delivery, sharply reducing radiation exposure to organs such as the heart and lungs, very likely improves the balance between benefits and risks for patients treated today.

Why this trial matters
It provides the longest planned, as well as median follow-up, of any randomised breast cancer radiation therapy trial.
It shows that treatment benefits and risks continue to evolve well beyond 15–20 years.
It demonstrates that node‑negative patients experience similar long‑term trade‑offs as the overall trial population.
It informs ongoing discussions on optimising and potentially de-escalating treatments in favourable-risk breast cancer.
Conducted by the EORTC Radiation Oncology and Breast Cancer Groups, trial 22922/10925 remains a cornerstone study for understanding the long‑term impact of locoregional treatments in breast cancer and for guiding future research aimed at improving both survival and quality of life.

ESTRO 2026 presentation number: 5580 Internal Mammary and Medial Supraclavicular irradiation in stage I-III breast cancer: 20 years results of the randomised EORTC trial 22922/10925, including in pN0 patients (Presenter: Philip Poortmans & Orit Kaidar-Person)

Funding: This study was supported by donations from the La Ligue nationale contre le cancer from France; the KWF Kanker Bestrijding from the Netherlands; and from the Kom op tegen Kanker (Stand up to Cancer), the Flemish Cancer Society from Belgium.

The fellowship of Lydia Champezou was financially supported by the EORTC Cancer Research Fund (ECRF).

(Press release, EORTC, MAY 17, 2026, View Source [SID1234665809])